DOOR USING EXTERNAL MOMENTUM

Cross-Reference to Related Application

[0001] This application claims the benefit under 35 U.S.C. §1 19 of US

Application No. 62/683155 filed 1 1 June 2018 and entitled SYSTEM AND METHOD FOR AUTOMATICALLY OPENING AND CLOSING A DOOR USING EXTERNAL MOMENTUM which is hereby incorporated herein by reference for all purposes.

Technical Field

[0002] This invention relates to door opening and/or closing technologies. This invention relates specifically to systems and methods for automatically opening and/or closing a door.

Background

[0003] Automatic door opening and/or closing systems are widely used to automatically open and/or close a door in the presence of a human, vehicle, animal, etc. desiring to pass through the door. A typical method involves using an electrically powered motion sensor to detect motion proximate to a door. The motion sensor may, for example, be a passive infrared sensor, an area reflective sensor, an ultrasonic sensor or the like. Such motion sensors, however, often inadvertently initiate opening and/or closing of a door even if a human, vehicle, animal, etc. is merely transversely passing by the door resulting in, for example, energy loss from a building or accelerated wear of an automatic door opening and/or closing system. Such motion sensors require an electrical power source such as a battery, electrical power line or the like.

[0004] Another typical method involves using a pressure sensor to detect a presence proximate to a door. The pressure sensor, may, for example, be a mechanical sensor, electro-mechanical sensor or the like. Weight of a human, vehicle, animal, etc. desiring to pass through the door exerted on such pressure sensors activates the pressure sensors. Such pressure sensors, however, are activated irrespective of the existence of motion (i.e. a human, vehicle, animal, etc. may be stationary on the pressure sensor) or direction of motion (e.g. transverse to a door, passing through a door, etc.). [0005] Known methods for automatically opening and/or closing a door typically actuate opening and/or closing of a door using powered mechanisms such as an electrically powered hydraulic mechanism, an electrically powered pneumatic mechanism, a gasoline powered hydraulic mechanism, a gasoline powered pneumatic mechanism or the like.

[0006] Attempts have been made to design automatic door opening and/or closing systems that are self-powered (i.e. do not require a power source).

Examples of efforts in this regard include the following: US patent No. 2,166,743;

CN patent publication 106812406 (A); FR patent publication No. 2,629,857; and US patent No. 5,720,132.

[0007] There is a general desire to provide an automatic door opening and/or closing system that is unresponsive to motion or presence of humans, vehicles, animals, etc. not intending to pass through the door. There is also a general desire to provide a self-powered system having characteristics that improve upon those known in the prior art.

[0008] The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.

Summary

[0009] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other improvements.

[0010] One aspect of the invention provides an automatic door opening and/or closing system for automatically opening and/or closing a door. The system senses motion towards or away from the door and actuates opening and/or closing of the door accordingly. The system may comprise a door, a presence detector placed on either side of the door and along a passageway through the door, and a hydraulic mechanism for actuating opening and/or closing of the door. The door may, for example, comprise a sliding door, a multi-panel door, a swing-out style door or the like. The presence detectors may be sensitive to motion on upper surfaces of plates contained within the presence detectors. Momentum from motion towards or away from the door horizontally moves the plates towards or away from the door respectively. Movement of a presence detector plate (which may be described more broadly as a“detecting surface”) may displace fluid from a fluid filled reservoir. In some embodiments, each presence detector comprises two distinct fluid filled reservoirs: one reservoir configured for opening the door; and one reservoir configured for closing the door. Fluid lines may supply the displaced fluid to the hydraulic mechanism. The fluid lines may be coupled at one end to a presence detector and to the hydraulic mechanism at an opposing end. Supplying fluid to the hydraulic mechanism may actuate the hydraulic mechanism to open or close the door. The fluid may have a viscosity sufficient to actuate the hydraulic mechanism. Actuation of the hydraulic mechanism by fluid displaced from one reservoir may remove previously displaced fluid from the hydraulic mechanism into the other reservoir thereby refilling the previously displaced reservoir. The two reservoirs may be opposing. Displacement of fluid from a reservoir configured to open the door may actuate opening of the door and may refill a reservoir configured to close the door. Likewise, displacement of fluid from a reservoir configured to close the door may actuate closing of the door and refill a reservoir configured to open the door. The system may be operable without a power source.

[0011] In some embodiments a detecting surface of a presence detector (e.g. a plate of the presence detector) is split into a plurality of detecting surfaces (e.g. a plurality of plates). In some embodiments the detecting surface is split into two plates.

[0012] In some embodiments a detecting surface moves laterally at one end of a presence detector and vertically at an opposing end of the presence detector.

[0013] Upon movement of a first presence detector plate towards the door, fluid from a reservoir configured to open the door may be displaced and supplied to the hydraulic mechanism opening the door. In some embodiments, the door remains open until motion away from the door is detected using a second presence detector and the first presence detector has returned to its neutral (i.e. inactive) state.

[0014] In some embodiments, the reservoirs are below a lower surface of a plate. In some embodiments, each fluid filled reservoir may be replaced by a plurality of fluid filled reservoirs. In some embodiments one or more of the fluid filled reservoirs may be replaced with electronics.

[0015] In some embodiments, each presence detector is fluidly isolated from the other presence detector. In such embodiments, the hydraulic mechanism includes two actuators. Each actuator may be fluidly coupled to one presence detector. Displacement of fluid in a first presence detector may actuate a first actuator.

Actuation of the first actuator may synchronously actuate a second actuator displacing fluid in a second presence detector in a manner identical to displacement of fluid in the first presence detector (e.g. the second actuator mirrors the first actuator).

[0016] In some embodiments, presence detectors are configured for opening of the door to take precedence over closing of the door (i.e. if both motion towards and away from the door are simultaneously sensed, motion towards the door takes precedence and the door is opened). In some embodiments, presence detectors are configured to detect motion from only a class or subclass of objects.

[0017] In some embodiments, pressure of displaced fluid is varied, varying the rate at which the door is opened and/or closed. For example, increasing pressure of the displaced fluid within the fluid lines may increase the rate of opening or closing of the door. Conversely, decreasing pressure of the displaced fluid within the fluid lines may decrease the rate of opening or closing of the door.

[0018] Another aspect of the invention provides a hydraulic mechanism for actuating the opening and/or closing of the door.

[0019] In some embodiments, the hydraulic mechanism comprises a fluid actuated piston having a shaft (for example, a“rod”) mounted to the door. Supplied fluid may actuate extension or contraction of the shaft. In some embodiments, the hydraulic mechanism comprises a second fluid actuated piston with a second shaft mounted to the door. In systems where the hydraulic mechanism comprises two fluid actuated pistons, the two fluid actuated pistons may be synchronized.

[0020] In some embodiments, the hydraulic mechanism comprises a geared actuator. The geared actuator may comprise a turbine fixedly coupled to an axle and a gear fixedly coupled to an end of the axle distal from the turbine. Movement of fluid within the geared actuator (i.e. upon fluid being supplied to the geared actuator) may rotate the turbine thereby also rotating the axle and gear. The gear may comprise a toothed portion lockingly engageable with a toothed track of the door (which may, for example, be described as a rack and pinion gear in some embodiments). Rotation of the gear in one direction may open the door and rotation of the gear in an opposite direction may close the door. In one embodiment, the hydraulic mechanism comprises a second geared actuator with a second gear having a second toothed portion engageable with a second track of the door. In such embodiment, the geared actuators may be synchronized.

[0021] In some embodiments, the hydraulic mechanism comprises a fluid actuated hinge mounted to a swing-out style door. The fluid actuated hinge may comprise an actuator unit, a hinge member having a toothed portion and hinge plates. The actuator unit may comprise a turbine fixedly coupled to an axle and a gear fixedly coupled to an end of the axle distal from the turbine. Movement of fluid within the actuator unit (i.e. upon fluid being supplied to the actuator unit) may rotate the turbine thereby rotating the axle and the gear. The gear may comprise a toothed portion lockingly engageable (or meshable) with a toothed portion of the hinge member. Rotation of the gear may rotate the hinge member varying a radial separation of the hinge plates. In some embodiments, increasing radial separation opens the door while decreasing radial separation closes the door. In one embodiment, the fluid actuated hinge may comprise a second actuator unit having a second gear having a second toothed portion lockingly engageable with a toothed portion of a second hinge member. In such embodiment, the actuator units may be synchronized.

[0022] A further aspect of the invention provides mechanisms for displacing fluid from the fluid filled reservoirs contained within a presence detector. The presence detector may comprise a plate supported by springs in a neutral (i.e. inactive) state of the presence detector. The springs may comprise first and second horizontal springs engageable with first and second vertical surfaces of the plate, and first and second vertical springs engageable with a lower surface of the plate. Motion of the plate may compress one or more springs. In some embodiments, the plate’s movement is arcuate (i.e. the plate initially moves horizontally (as a result of horizontal motion on an upper surface of the plate) and subsequently downwards (as a result of weight being exerted on the plate)). Upon motion and/or weight no longer being exerted on the plate, relaxing of springs that were compressed as a result of the plate’s movement may return the plate to a resting position and the presence detector to its neutral state. In some embodiments, a presence detector’s neutral state comprises the plate centered within a horizontal plane of the presence detector. Sensitivity of the presence detector may be configurable by varying spring constants of the springs.

[0023] In some embodiments, levers displace fluid from a reservoir. Movement of the plate may torque (e.g. pivot) triggering levers around mounting points on the lower surface of the plate. Pivoting of the triggering levers may raise first and second raising levers raising the reservoir upwards. Raising the reservoir upwards may engage the reservoir with a compression member displacing fluid contained within the reservoir.

[0024] In some embodiments, an actuating fluid displaces fluid from a reservoir. In such embodiments, the plate comprises knobs on the lower surface of the plate. Movement of the plate may engage the knobs with actuating fluid filled chambers displacing the actuating fluid into an actuating bladder enclosing the reservoir.

Displaced actuating fluid may raise a reservoir engaging the reservoir with a compression member displacing fluid contained within the reservoir.

[0025] In some embodiments, the plate comprises a protruding compression member extending along the plate for displacing fluid from a reservoir. The fluid filled reservoir may rest in a cavity under the protruding compression member. Movement of the plate engages the protruding compression member with the reservoir displacing fluid contained within the reservoir. In some embodiments, reservoirs mirror a cross-section of the protruding compression member. In one embodiment, the protruding compression member has a semi-circular cross section. In another embodiment, the protruding compression member has a triangular cross section.

[0026] In some embodiments, the presence detector comprises first and second arms mounted to the lower surface of the plate. The first and second arms may be coupled to first and second rollers. First and second rollers may be glidable along a curved track. First and second pads may be fixedly coupled to ends of the first and second arms distal from the plate. Movement of the plate pivots the first and second arms. Pivoting of the first or second arms glides the first or second rollers respectively along the track. Movement of the plate may engage the first or second pad with first or second reservoirs respectively displacing fluid contained within an engaged reservoir.

[0027] In some embodiments, the presence detector comprises supporting guides for vertically supporting and guiding motion of the plate. Gliding members mounted to a lower surface of the plate may engage levers raising first or second reservoirs displacing fluid contained within the first or second reservoirs.

[0028] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed description.

Brief Description of the Drawings

[0029] Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive. [0030] FIG. 1 illustrates a plan view of an embodiment of an automatic door mechanism in accordance with the methods and systems described herein.

[0031] FIG. 1 A illustrates a vertical cross-sectional view of an embodiment of an automatic door mechanism in accordance with the systems and methods described herein. [0032] FIGS. 2A, 2B, 2C and 2D illustrate schematic views of embodiments of a hydraulic mechanism according to the systems and methods described herein.

[0033] FIGS. 3A and 3B illustrate schematic views of embodiments of a hydraulic mechanism according to the systems and methods described herein.

[0034] FIG. 4 illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein.

[0035] FIG. 5 illustrates a vertical cross-sectional view of the presence detector shown in FIG. 4 activated to open a door according to the systems and methods described herein. [0036] FIG. 6 illustrates a vertical cross-sectional view of the presence detector shown in FIG. 4 activated to close a door according to the systems and methods described herein.

[0037] FIGS. 7 to 7D illustrate a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein.

[0038] FIGS. 8 to 8B illustrate a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein.

[0039] FIG. 9 illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein. FIG. 9A illustrates a vertical cross-sectional view of the FIG. 9 presence detector activated to open a door. FIG. 9B illustrates a vertical cross-sectional view of the presence detector shown in FIG. 9 activated to close a door.

[0040] FIG. 10 illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein. FIG.

10A illustrates a cross-sectional view of the presence detector shown in FIG. 10 activated to open a door. FIG. 10B illustrates a cross-sectional view of the presence detector shown in FIG. 10 activated to close a door.

[0041] FIG. 10C illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein. FIG.

10D illustrates a vertical cross-sectional view of the presence detector shown in FIG. 10C activated to open a door. FIG. 10E illustrates a vertical cross-sectional view of the presence detector shown in FIG. 10C activated to close a door.

[0042] FIG. 1 1 illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein. FIG.

1 1 A illustrates a vertical cross-sectional view of the presence detector shown in FIG. 1 1 activated to open a door. FIG. 1 1 B illustrates a vertical cross-sectional view of the presence detector shown in FIG. 1 1 activated to close a door.

[0043] FIG. 12 illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein. FIG.

12A illustrates a vertical cross-sectional view of the presence detector shown in FIG. 12 activated to open a door. FIG. 12B illustrates a vertical cross-sectional view of the presence detector shown in FIG. 12 activated to close a door.

[0044] FIG. 13 illustrates vertical a cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein. FIG.

13A illustrates a vertical cross-sectional view of the presence detector shown in FIG.

13 activated to open a door. FIG. 13B illustrates a vertical cross-sectional view of the presence detector shown in FIG. 13 activated to close a door.

[0045] FIGS. 14A to 14C illustrate schematic views of an exemplary mechanism according to the systems and methods described herein.

[0046] FIGS. 15A and 15B illustrate schematic views of an exemplary fluid pressure regulator according to the systems and methods described herein.

[0047] FIG. 16 illustrates a schematic view of an exemplary automatic door mechanism according to the systems and methods described herein.

[0048] FIGS. 17A to 17E schematically illustrate a vertical cross-sectional view of an embodiment of an automatic door mechanism in accordance with the systems and methods described herein.

[0049] FIG. 18 schematically illustrates a vertical cross-sectional view of an embodiment of a presence detector according to the systems and methods described herein.

Description

[0050] Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

[0051] Fig. 1 illustrates a plan view of an exemplary automatic door mechanism 10 according to an embodiment. Automatic door mechanism 10 includes presence detectors 4 and a door 8. Presence detectors 4 are installed on either side of a passageway 2 passing through door 8. Door 8 may, for example, be a sliding door.

In some embodiments door 8 is a multi-panel door having two or more panels. Door 8 may, for example, be composed of one or more panels of wood, composite, particle board, plastic, metal, glass, fiberglass, cement or the like.

[0052] In the illustrated exemplary embodiment of Fig. 1 , door 8 is installed within a partition 6. In some embodiments, door 8 may be installed between two distinct partitions 6. One or more partitions 6 separate area 6A from area 6B and/or area 6B from area 6A. Partition 6 may, for example, be a wall, fence, screen, barrier, divider or the like. Passage from area 6A to area 6B and/or from area 6B to area 6A may, for example, be accessible through door 8.

[0053] Presence detectors 4 are enclosed by a medium 3 as shown in Fig. 1 A. Medium 3 may include air, earth, gravel, sand, cement, synthetic mediums, commercially available construction materials or the like. Medium 3 may or may not be uniform throughout automatic door mechanism 10. In some embodiments, plate 5 of a presence detector 4 is level with surface 3A. In some embodiments, plate 5 is below or above surface 3A. In some embodiments, plate 5 includes cambered and/or angled edges level with surface 3A. In some embodiments, the primary upper surface of plate 5 may be planar. In some embodiments, the primary upper surface of plate 5 is smooth, textured, etc. The primary upper surface of plate 5 may be any shape (including a free-form shape). In some embodiments the primary upper surface of plate 5 is rectangular, triangular, circular, ellipsoidal, hexagonal, octagonal or the like.

[0054] Automatic door mechanism 10 is sensitive to motion towards and/or away from door 8, including motion along passageway 2. Detection of such motion transitions automatic door mechanism 10 from a passive (i.e. inactive) state to an active state actuating opening and/or closing of door 8. Motion transverse in direction to passageway 2 neither transitions automatic door mechanism 10 into an active state nor maintains automatic door mechanism 10 in an already active state. Detection of motion towards door 8 preferably actuates opening of door 8.

Conversely, detection of motion away from door 8 preferably actuates closing of door 8.

[0055] As an exemplary illustration, in response to a human walking towards door 8 along passageway 2, automatic door mechanism 10 actuates opening of door 8. Upon the human passing through door 8 and beginning to walk away from door 8, automatic door mechanism 10 actuates closing of door 8. [0056] Automatic door mechanism 10 is configurable to detect motion of objects (i.e.“movable bodies”) such as, for example, humans, animals, vehicles, trailers, wheelchairs, gurneys, movable containers, parcels, loads or the like. In some embodiments, automatic door mechanism 10 is configurable to detect motion exclusively of a class or subclass of objects. In such embodiments, sensitivity of presence detectors 4 may be configured for detection of the desired class or subclass of objects.

[0057] An object’s motion along passageway 2 on either side of door 8 is sensed using, for example, presence detectors 4. Plates 5 of presence detectors 4 are sensitive to motion on upper surfaces of plates 5. Specifically, plates 5 are movable by momentum from an object’s motion on the upper surfaces of plates 5.

[0058] Plate 5 contemporaneously mirrors an object’s motion towards or away from door 8. An object’s motion towards door 8 moves plate 5 towards door 8. An object’s motion away from door 8 moves plate 5 away from door 8. In some embodiments, an object’s weight on plate 5 may additionally result in downward movement of plate 5. In such embodiments, movement of plate 5 is arcuate.

[0059] Movement of plate 5 initiates supply of fluid 12 (not shown) from a presence detector 4 to hydraulic mechanism 30. In some embodiments, movement of plate 5 irreversibly initiates supply of fluid 12 from a presence detector 4 (i.e. supply of fluid 12 will not be interrupted upon movement of plate 5 in an opposing direction).

[0060] Hydraulic mechanism 30 is coupled to door 8 and provides the means for opening and closing door 8. In some embodiments, hydraulic mechanism 30 is enclosed within a frame of door 8. Automatic door mechanism 10, including hydraulic mechanism 30, may be operated without a power source (e.g. without electrical power, gas, etc.).

[0061] Fluid lines 1 1 A, 1 1 B may carry fluid from presence detector 4 to hydraulic mechanism 30 and from hydraulic mechanism 30 to presence detector 4 creating a closed loop system. Fluid lines 1 1 A, 1 1 B may, for example, be hoses, piping, tubes, conduits or the like. In some embodiments, fluid lines 1 1 A, 1 1 B may, for example, be coupled to presence detectors 4 and hydraulic mechanism 30 as illustrated by the small dashed lines in Fig. 1 A. [0062] Automatic door mechanism 10 may include two supplies of fluid 12 (this is not mandatory). Fluid lines 1 1 A interface a first fluid supply with hydraulic mechanism 30. Fluid lines 1 1 B interface a second fluid supply with hydraulic mechanism 30. Fluid 12 flowing in fluid lines 1 1 A may, for example, be isolated from fluid 12 flowing in fluid lines 1 1 B. Fluid lines 1 1 A, 1 1 B are interfaced to hydraulic mechanism 30 in an opposing manner such that fluid 12 from fluid line 1 1 A actuates hydraulic mechanism 30 in an opposing manner to fluid 12 from fluid line 1 1 B. In some embodiments, fluid 12 supplied by fluid lines 1 1 A actuates opening of door 8 while fluid 12 supplied by fluid lines 1 1 B actuates closing of door 8. In some embodiments, fluid 12 supplied by fluid lines 1 1 A actuates closing of door 8 while fluid 12 supplied by fluid lines 1 1 B actuates opening of door 8.

[0063] Removal of fluid 12 from hydraulic mechanism 30 complements supply of fluid 12 into hydraulic mechanism 30. For example, supplying fluid 12 from presence detector 4 to hydraulic mechanism 30 to open door 8 removes a volume of fluid 12 from hydraulic mechanism 30 into presence detector 4 replenishing fluid 12 for closing door 8. Similarly, supplying fluid 12 from presence detector 4 to hydraulic mechanism 30 to close door 8 removes a volume of fluid 12 from hydraulic mechanism 30 into presence detector 4 replenishing fluid 12 for opening door 8. A fluid outflow rate of fluid 12 flowing out of hydraulic mechanism 30 may, for example, be equivalent to a fluid inflow rate of fluid 12 into hydraulic mechanism 30. In some embodiments, a fluid outflow rate of fluid 12 flowing out of hydraulic mechanism 30 is proportional to, but not equivalent to, a fluid inflow rate of fluid 12 flowing into hydraulic mechanism 30.

[0064] Fluid 12 has a viscosity sufficient to actuate hydraulic mechanism 30. Fluid 12 may, for example, be water, a petroleum-based liquid, a phosphate-ester based liquid, a mineral oil based liquid, a water-oil emulsion, a water-glycol mix or the like. In some embodiments, fluid 12 remains liquid in cold environments (e.g. does not freeze in a cold/winter environment). In some embodiments, fluid 12 has a freezing point below -35 degrees Celsius.

[0065] A rate at which door 8 is opened/and or closed may be varied by varying pressure of fluid 12 within fluid lines 1 1A, 1 1 B and/or hydraulic mechanism 30. In some embodiments, pressure of fluid 12 may be varied, for example, using a pressure control valve or the like. In some embodiments, pressure of fluid 12 may be varied, for example, by connecting a pressure control tank in parallel to fluid lines 1 1 A and/or 1 1 B. In some embodiments, this process may be described as“metering in and metering out”.

[0066] In some embodiments, hydraulic mechanism 30 includes a fluid actuated piston 32 as illustrated in Fig. 2A. Piston 32 may include shaft 33 and line connects 34A, 34B. Shaft 33 may be mounted to a bottom corner 9A of door 8. In some embodiments, shaft 33 may be mounted to a top corner 9B of door 8 or any other mountable surface of door 8.

[0067] Retraction of shaft 33 opens door 8 and extension of shaft 33 closes door 8. In an alternative embodiment, extension of shaft 33 opens door 8 and contraction of shaft 33 closes door 8.

[0068] Shaft 33 is mountable to door 8 using, for example, screws, bolts, nails, rivets, fixtures, magnets, a welding technique, an adhesion technique, a bonding technique or the like. Piston 32 may comprise any piston actuated by fluid.

[0069] Line connects 34A, 34B may interface fluid lines 1 1 A, 1 1 B with piston 32. For example, fluid lines 1 1 A may be removably coupled to line connect 34A and fluid lines 1 1 B may be removably coupled to line connect 34B. In another embodiment, fluid lines 1 1 A may, for example, be coupled to line connect 34B and fluid lines 1 1 B may be removably coupled to line connect 34A.

[0070] Line connects 34A, 34B may, for example, be bidirectional, carrying fluid 12 into and out of piston 32. In some embodiments, supplying fluid 12 into piston 32 via line connect 34A extends shaft 33 and removes fluid 12 out of piston 32 via line connect 34B. Conversely, supplying fluid 12 into piston 32 via line connect 34B retracts shaft 33 and removes fluid 12 out of piston 32 via line connect 34A. In some embodiments, supplying fluid 12 into piston 32 via line connect 34B extends shaft 33 and removes fluid 12 out of piston 32 via line connect 34A. In such embodiments, supplying fluid 12 into piston 32 via line connect 34A retracts shaft 33 and removes fluid 12 out of piston 32 via line connect 34B.

[0071] In some embodiments, hydraulic mechanism 30 includes a second piston 32 (not shown) coupled to a door 8. A second shaft 33 (not shown) may be mounted to top corner 9B or any other mountable surface of door 8. In such embodiments, the two pistons 32 may be synchronized and may be functionally equivalent.

[0072] Fig. 2B illustrates an exemplary embodiment of a geared actuator 36 of an alternative hydraulic mechanism 30.

[0073] Exemplary geared actuator 36 includes a turbine 37 fixedly coupled to an axle 38. Gear 39 may be fixedly coupled to end 38A of axle 38. Gear 39 may engage (or mesh with) toothed track 35 of door 8 as illustrated in Fig. 2C. Although illustrated on a lower surface of door 8, toothed track 35 may, for example, be included on an upper surface of door 8. Rotation of turbine 37 rotates axle 38 and gear 39 likewise. In a preferred embodiment, a vertical centre axis of axle 38 is aligned with a vertical centre axis of door 8.

[0074] In some embodiments, clockwise and counterclockwise rotation of gear 39 opens and closes door 8 respectively. In some embodiments, clockwise and counterclockwise rotation of gear 39 closes and opens door 8 respectively.

[0075] Movement of fluid 12 within cavity 36C of geared actuator 36 rotates turbine 37. For example, in some embodiments, movement of fluid 12 in the direction from line connect 36A to line connect 36B rotates turbine 37 clockwise while movement of fluid 12 in the direction from line connect 36B to line connect 36A rotates turbine 37 counterclockwise. In some embodiments, movement of fluid 12 in the direction from line connect 36A to line connect 36B rotates turbine 37 counterclockwise while movement of fluid 12 in the direction from line connect 36B to line connect 36A rotates turbine 37 clockwise.

[0076] Line connects 36A, 36B may be removably coupled to fluid lines 1 1 A,

1 1 B interfacing presence detectors 4 with geared actuator 36. In a preferred embodiment, each line connect 36A, 36B is bidirectional, passing fluid 12 both into and out of cavity 36C. In some embodiments, fluid lines 1 1 A, 1 1 B are removably coupled to line connect 36A, 36B respectively. In some embodiments, fluid lines 1 1 A, 1 1 B are removably coupled to line connects 36B, 36A respectively.

[0077] Hydraulic mechanism 30 may optionally include a second geared actuator 36’ as shown in Fig. 2D. Gear 39’ may be engaged with (or meshed with) toothed track 35’ of door 8. Toothed track 35’ is equivalent to track 35. Geared actuator 36’ is equivalent to geared actuator 36. If geared actuator 36’ is included in hydraulic mechanism 30, geared actuators 36, 36’ may be synchronized. In a preferred embodiment, vertical centre axes of axles 38, 38’ (not shown) respectively are aligned with a vertical centre axis of door 8.

[0078] In some embodiments (not shown) a cable or belt coupled to geared actuator 36 is used to actuate opening and/or closing of door 8. In such

embodiments, the cable or belt is mounted to door 8 using any mounting technique described herein. Rotation of axle 38 and/or gear 39 extends and retracts the cable or belt actuating opening and/or closing of door 8. The cable or belt may, for example, be any commercially available cable, wire, chain, rope, belt or the like. In some embodiments gear 39 is replaced with a pulley, drum, etc. around which the cable or belt may be wound.

[0079] In some embodiments of the invention, door 8 is a swing-out style door.

In such embodiments, hydraulic mechanism 30 may include one or more fluid actuated hinges 40 mounted to door 8. Hinge 40 may, for example, be mounted to door 8 using screws, bolts, nails, rivets, fixtures, magnets or the like. In some embodiments, hinge 40 may be welded to door 8. In some embodiments, hinge 40 may be bonded and/or adhered to door 8.

[0080] Fig. 3A illustrates an exemplary embodiment of hinge 40. Hinge 40, as illustrated, includes an actuator unit 41 pivotally coupled to hinge member 46.

Actuator unit 41 includes a gear 45 having a toothed portion 45A engageable (or meshable) with a toothed portion 46A of hinge member 46. Toothed portion 46A, may, for example, mirror toothed portions 45A. In such embodiments, clockwise and counterclockwise rotation of gear 45 rotates hinge member 46 clockwise and counterclockwise respectively. In some embodiments, clockwise and

counterclockwise rotation of gear 45 rotates hinge member 46 counterclockwise and clockwise respectively.

[0081] Hinge plates 51 are fixedly coupled to hinge members 46, 48. In some embodiments, clockwise pivoting of hinge member 46 reduces radial separation between hinge plates 51 while counterclockwise pivoting of hinge member 46 increases radial separation between hinge plates 51 . In some embodiments, clockwise pivoting of hinge member 46 increases radial separation between hinge plates 51 while counterclockwise pivoting of hinge member 46 reduces radial separation of hinge plates 51 .

[0082] Turbine 42 is fixedly coupled to an axle 44. Gear 45 is fixedly coupled to end 44A of axle 44. Rotation of turbine 42 rotates axle 44 and gear 45 likewise.

[0083] Turbine 42 is responsive to movement of fluid 12 within cavity 41 C of actuator unit 41 . For example, in some embodiments, movement of fluid 12 in the direction from line connect 41 A to line connect 41 B rotates turbine 42 clockwise while movement of fluid 12 in the direction from line connect 41 B to line connect 41 A rotates turbine 42 counterclockwise. In some embodiments, movement of fluid 12 in the direction from line connect 41 A to line connect 41 B rotates turbine 42

counterclockwise while movement of fluid 12 in the direction from line connect 41 B to line connect 41 A rotates turbine 42 clockwise.

[0084] Line connects 41 A, 41 B may interface fluid lines 1 1 A, 1 1 B of presence detectors 4 with actuator unit 41 . In a preferred embodiment, each line connect 41 A, 41 B is bidirectional, passing fluid 12 both into and out of cavity 41 C. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 41 A and fluid lines 1 1 B are removably coupled to line connect 41 B. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 41 B and fluid lines 1 1 B are removably coupled to line connect 41 A.

[0085] In some embodiments, hinge 40 may optionally include a second actuator unit 4T rotationally coupled to hinge member 48’ as shown in Fig. 3B. In such embodiments, the actuator units 41 , 4T are synchronized. Actuator units 41 ,

4T may be functionally equivalent. Hinge member 48’ may be functionally equivalent to hinge member 46 described herein.

[0086] In embodiments where hydraulic mechanism 30 comprises two actuators (e.g. a second piston 32’, a second geared actuator 36’, a second hinge 40, a second actuator unit 4T of hinge 40), first and second presence detectors 4 on opposing sides of door 8 may, for example, each be connected to a distinct actuator. In such embodiments, actuation of one actuator synchronously actuates the second actuator and flow of fluid 12 in first presence detector 4 synchronously mirrors flow of fluid 12 in second presence detector 4. In such embodiments, fluid 12 in the first presence detector may be separate and distinct from fluid 12 in the second presence detector.

[0087] In a preferred embodiment of the invention, automatic door mechanism 10 is configured for opening of door 8 to take precedence over closing of door 8. As a presence detector 4 is installed on either side of door 8, situations may arise where motion towards door 8 on one side of door 8 is detected simultaneously with motion away from door 8 on another side of door 8. In such situations, automatic door mechanism 10 may be responsive to sensed motion towards door 8 actuating opening of door 8 and may be unresponsive to the sensed motion away from door 8.

[0088] To avoid, for example, inadvertent closing of door 8 while an object has not entirely passed through door 8, automatic door mechanism 10 may, for example, be configured with a delayed closing of door 8. For example, automatic door mechanism 10 may be configured to not actuate closing of door 8 until motion away from door 8 is detected and plate 5 of the presence detector 4 which initiated opening of door 8 has returned to its neutral (i.e. inactive) state.

[0089] Fig. 4 illustrates an exemplary embodiment of a presence detector 4 in its neutral (i.e. inactive) state.

[0090] Exemplary presence detector 4 illustrated in Fig. 4 includes a plate 5 vertically supported by springs 166A, 166B and horizontally biased by springs 164A, 164B. Sensitivity of presence detector 4 is configurable, for example, by varying spring constants of springs 164A, 164B, 166A and/or 166B. In a preferred embodiment, springs 164A, 164B, 166A and/or 166B have spring constants such that springs 164A, 164B, 166A and 166B are substantially uncompressed in the neutral state of presence detector 4.

[0091] Below a lower surface of plate 5, presence detector 4 may include a lever system 20 mounted to plate 5. Movement of plate 5 initiates lever system 20 to supply fluid 12 to hydraulic mechanism 30.

[0092] Lever system 20 includes fluid filled reservoirs 102, 106. Reservoirs 102, 106 are compressible and include an impermeable membrane layer. Reservoirs 102, 106 include line connects (e.g. ports) 103, 107 respectively. Line connects 103, 107 carry fluid 12 into and/or out of reservoirs 102, 106 respectively. Reservoir 102 may be fluidly isolated from reservoir 106.

[0093] Fluid lines 1 1 A, 1 1 B may be removably coupled to line connects 103,

107. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 103 and fluid lines 1 1 B are removably coupled to line connect 107. In some embodiments, fluid lines 1 1 B are removably coupled to line connect 103 and fluid lines 1 1 A are removably coupled to line connect 107.

[0094] Levers 122, 124, 126, 132, 134, 136, 138 actuate lever system 20. Mounts 1 12, 1 14, 1 16 couple lever system 20 to plate 5. Pin or axle 121 pivotally couples trigger lever 122 to mount 1 12. Likewise, pin or axle 123 pivotally couples trigger lever 124 to mount 1 14 and pin or axle 125 pivotally couples trigger lever 126 to mount 1 16.

[0095] Raising levers 132, 138 are pivotally coupled to trigger levers 122, 126 respectively using pins or axles 131 , 137 respectively. Raising levers 134, 136 are pivotally coupled to trigger lever 124 using pin or axle 133. Pins or axles 131 , 133, 137 pass through bottom support 160 pivotally coupling lever system 20 to bottom support 160.

[0096] Platforms 104, 108 support, raise and lower reservoirs 102, 106 respectively. Pins or axles 141 , 143 pivotally couple raising levers 132, 134 respectively to platform 104. Likewise, pins or axles 145, 147 pivotally couple raising levers 136, 138 respectively to platform 108.

[0097] In some embodiments lever 124 may be described as a reverse gear. Levers 134 and 136 may be coupled to the reverse gear. In such embodiments, clockwise pivoting of lever 126 pivots lever 138 upwards. Concurrently, the reverse gear pivots clockwise thereby pivoting lever 136 upwards. Counterclockwise pivoting of lever 122 pivots lever 132 upwards. Concurrently the reverse gear pivots counterclockwise thereby pivoting lever 134 upwards. [0098] Momentum from motion of an object towards door 8 in direction X1 on an upper surface of plate 5 moves plate 5 horizontally towards door 8 and downwards towards upper surface 160B of bottom support 160 as shown in Fig. 5. Horizontal movement of plate 5 in direction X1 , for example, pivots trigger levers 122, 124, 126 clockwise around mounts 1 12, 1 14, 1 16 respectively. Clockwise pivoting of trigger levers 124, 126 pivots raising levers 136, 138 respectively upwards around pins or axles 133, 137 respectively. Upwards pivoting of raising levers 136, 138 raises platform 108 engaging reservoir 106 with compression member 109. Engagement of reservoir 106 with compression member 109 compresses reservoir 106 displacing fluid 12 from reservoir 106 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 106 actuates opening of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 102. Clockwise pivoting of trigger levers 122, 124 does not pivot raising levers 132, 134.

[0099] Conversely, momentum from motion of an object away from door 8 in direction Y1 on an upper surface of plate 5 moves plate 5 horizontally away from door 8 and downwards towards upper surface 160B of bottom support 160 as shown in Fig. 6. Horizontal movement of plate 5 in direction Y1 , for example, pivots trigger levers 122, 124, 126 counterclockwise around mounts 1 12, 1 14, 1 16 respectively. Counterclockwise pivoting of trigger levers 122, 124 pivots raising levers 132, 134 respectively upwards around pins or axles 131 , 133 respectively. Upwards pivoting of raising levers 132, 134 raises platform 104 engaging reservoir 102 with compression member 101 . Engagement of reservoir 102 with compression member 101 compresses reservoir 102 displacing fluid 12 from reservoir 102 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 102 actuates closing of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 106. Counterclockwise pivoting of trigger levers 124, 126 does not pivot raising levers 136, 138.

[0100] In some embodiments one or more of pins or axles 131 , 133 and 137 are machined to have splines (or spokes, etc.). In some embodiments splines of pin or axle 133 mesh with opposing splines of the reverse gear to pivot lever 134 or 136 in an opposite direction of lever 132 or lever 138 respectively. [0101] In an alternative embodiment, motion in direction X1 raises reservoir 102 to actuate opening of door 8 while motion in direction Y1 raises reservoir 106 to actuate closing of door 8.

[0102] Horizontal movement of plate 5 in direction X1 compresses spring 164A while horizontal movement of plate 5 in direction Y1 compresses spring 164B. Downward movement of plate 5 towards upper surface 160B compresses springs 166A, 166B. Depending on an object’s weight, plate 5 rests on or above upper surface 160B. Where an object’s weight is lower than upward spring forces exerted on plate 5 by springs 166A, 166B, plate 5 rests above upper surface 160B. Where an object’s weight is equal to or higher than upward spring forces exerted on plate 5 by springs 166A, 166B, plate 5 rests on upper surface 160B. Upon an object’s weight no longer being exerted on an upper surface of plate 5, springs 164A, 164B, 166A and/or 166B return plate 5 to its neutral position.

[0103] In some embodiments a detecting surface of a presence detector 4 (or another embodiment of a presence detector described elsewhere herein) is split into a plurality of detecting surfaces. For example, the detecting surface may comprise a dual plate mechanism. The dual plate mechanism may comprise a laterally movable top plate and a vertically movable bottom plate. However this is not mandatory. In some embodiments the top plate may be vertically movable and the bottom plate may be laterally movable. In some embodiments movement of one plate collapses the plate towards the other plate.

[0104] Fig. 7 illustrates an example embodiment of a presence detector 4 comprising a dual plate mechanism. The dual plate mechanism comprises a top plate 105T and a bottom plate 105B. Top plate 105T is laterally movable. Top plate 105T may track lateral movement (e.g. momentum) of an object passing over an upper surface of top plate 105T. A pair of springs 179A and 179B may couple top plate 105T to bottom plate 105B. Lateral movement of top plate 105T collapses top plate 105T towards bottom plate 105B. Bottom plate 105B may then be compressed downwards. Vertical movement of bottom plate 105B may compress fluid in one or more fluid filled reservoirs (e.g. reservoirs 102, 106) as described elsewhere herein.

[0105] In one example case a person walking towards door 8 on an upper surface of top plate 105T moves top plate 105T laterally towards door 8 (see e.g. Fig. 7A). In some such cases top plate 105T also collapses vertically towards bottom plate 105B (see e.g. Fig. 7B). Vertical movement of top plate 105T may frictionally engage top plate 105T with bottom plate 105B. As the person continues to walk towards door 8, bottom plate 105B (and top plate 105T which is coupled to bottom plate 105B in the example embodiment) collapses downwards towards a bottom surface of presence detector 4 thereby compressing one or more fluid filled reservoirs to actuate opening of door 8 (see e.g. Figs. 7C and 7D). Likewise, a person walking away from door 8 moves top plate 105T laterally away from door 8 and bottom plate 105B downwards to actuate closing of door 8.

[0106] In some embodiments (see e.g. Fig. 7) presence detector 4 comprises a lever system operable to assist with movement of a detecting surface of presence detector 4. For example, the lever system may comprise a first end coupled to a bottom of the detecting surface. An opposing end of the lever system may glide across a bottom surface of presence detector 4 (or along a track coupled to a bottom surface of presence detector 4). In some embodiments a friction reducing member (e.g. a ball bearing, gliding wheel, or the like) is coupled to the opposing end of the lever system. Advantageously the lever system may smoothly transition the detecting surface between a neutral state and an active state. This may, for example, reduce the likelihood of injury, increase comfort, etc.

[0107] In some embodiments the lever system comprises a lever 171 as shown, for example, in Fig. 7. Lever 171 may be pivotally coupled to a detecting surface (e.g. plate 5, plate 105T, etc.) with a pin 170. Pin 170 may be inserted into a bore that extends through the detecting surface (e.g. plate 105T). Lever 171 may also be pivotally coupled to a connecting bracket 173. Pin or axle 172 may pivotally couple connecting bracket 173 to plate 105B. Pin or axle 172 may be inserted into a bore that extends through plate 105B. Connecting bracket 173 may optionally comprise supporting members 174A and/or 174B. Supporting members 174A and/or 174B may be configured to catch lever 171 . A friction reducing member 176 (e.g. a ball bearing, wheel, etc.) may be rotationally coupled to bracket 173 with pin or axle 175. Friction reducing member 176 may glide along (or follow) a track 177.

[0108] In some cases movement of a detecting surface of a presence detector 4 (or any other presence detector described elsewhere herein) simultaneously compresses fluid that both actuates opening and closing of door 8. In such cases valves (or another mechanism) control coupling of the compressed fluid to hydraulic mechanism 30 to appropriately control actuation of door 8 (e.g. appropriately couples the fluid lines to the fluid filled reservoir(s) to get desired actuation of door mechanism 10). For example, if movement of an object towards door 8 has been detected, one or more valves (or other mechanism(s)) may couple compressed fluid to hydraulic mechanism 30 such that door 8 is opened. If movement of an object away from door 8 has been detected, one or more valves (or other mechanism(s)) may couple compressed fluid to hydraulic mechanism 30 such that door 8 is closed. In some embodiments the lever system of Fig. 7 or a similar system may

mechanically actuate the valves (e.g. the lever system comprises an additional lever for controlling one or more valves).

[0109] In some embodiments a presence detector 4 comprises a single fluid filled reservoir (e.g. reservoir 102’ of Fig. 8). In such embodiments the single fluid filled reservoir may comprise two ports (e.g. ports 103’ and 107’ of Fig. 8) In such embodiments movement of the detecting surface of presence detector 4 (e.g. plate 5) couples fluid lines (e.g. fluid lines 1 1 A, 1 1 B) appropriately. For example, movement of the detecting surface towards door 8 couples the fluid lines to actuate opening of door 8. Movement of the detecting surface away from door 8 couples the fluid lines to actuate closing of door 8. Any present or future known valve (or valves) may be used. In some embodiments a lever or lever system coupled to the detecting surface facilitates pairing of the fluid lines to the fluid filled reservoir. In some embodiments the lever system of Fig. 7 facilitates pairing of the fluid lines to the fluid filled reservoir.

[0110] In some embodiments movement of a detecting surface of a presence detector 4 may actuate one or more mechanical switches. For example, movement of the detecting surface may actuate one or more mechanical push buttons or the like to open/close supply of fluid to fluid lines 1 1 A, 1 1 B accordingly.

[0111] In some embodiments (as shown in e.g. Fig. 8) a detecting surface of presence detector 4 is movable laterally only in one lateral direction (e.g. either towards door 8 or away from door 8). An opposing end of the detecting surface may only be vertically movable. For example, such detecting surface may move downwards upon a person walking towards door 8 (see e.g. Fig. 8A) and laterally away from door 8 upon a person walking away from door 8 (see e.g. Fig. 8B) or vice versa. The different motions of the detecting surface (e.g. vertical movement when the person is walking towards door 8 and lateral movement when the person is walking away from door 8) may trigger opening and/or closing of door 8 as described elsewhere herein. In some embodiments different movements of the detecting surface couple fluid lines (e.g. fluid lines 1 1 A, 1 1 B described elsewhere herein) differently. For example, downward movement of the detecting surface may couple the fluid lines to open door 8. Conversely lateral movement of the detecting surface away from door 8 may couple the fluid lines to close door 8. In such embodiments, downward movement of the detecting surface preferably actuates opening of door 8 and lateral movement actuates closing of door 8. In some embodiments (as shown in Fig. 8) such presence detector may comprise a lever system that is identical to (or similar to) the lever system shown in Fig. 7.

[0112] In some embodiments, walls of presence detector 4 may comprise one or more friction reducing members (e.g. members 178A, 178B, etc.) to assist with movement of a detecting surface. For example, a wall (or walls) of presence detector 4 may optionally comprise wheels to assist with lateral and/or downward movements of the detecting surface. Fig. 8 shows example wheels 178A and 178B. Additionally, or alternatively, presence detector 4 may comprise a lubricant delivery device (not shown) operable to deliver lubricant to surfaces of presence detector 4 that are likely to frictionally engage the detecting surface. In some embodiments presence detector 4 comprises a plurality of different friction reducing members (e.g. friction reducing wheels, bearings and/or a lubricant delivery device).

[0113] In preferred embodiments automatic door mechanism 10 and presence detector 4 are self-powered (i.e. do not require an external power source as described elsewhere herein). However, in some embodiments one or more fluid filled reservoirs below a detecting surface of a presence detector 4 (e.g. plate 5 described elsewhere herein) are replaced with electronics (e.g. electronic sensors, electronic connection points, etc.). The electronics may be configured to sense motion of the detecting surface. Electrical signals produced by the electronics may trigger actuation of automatic door mechanism 10. For example, a processor coupled to the electronics may detect movement of the detecting surface towards the door thereby triggering opening of door 8. The processor may also be configured to actuate movement of fluid in order to actuate movement of door 8 as desired (e.g. control a hydraulic fluid pump that provides fluid to actuate movement of door 8 using any of the methods described elsewhere herein). Additionally, or alternatively, a processor may be configured to control one or more valves coupling a fluid source (or sources) to one or more fluid lines to actuate opening/closing of door 8. In some embodiments the processor is configured to actuate an electronic mechanism (e.g. an electronic gear system coupled to a swing out door, etc.) to open and/or close door 8.

[0114] In some such embodiments each fluid filled reservoir of presence detector 4 is replaced with an electronic sensor, electronic connection point, etc. For example, each fluid filled reservoir may be replaced with an electro-mechanical sensor such as a push button configured to be triggered by motion of the detecting surface that would have compressed the fluid filled reservoir that the push button is replacing. As another example, a presence detector 4 may comprise a lever (or levers) configured to actuate one or more electronic sensors as the detecting surface of presence detector 4 moves. As another example, a presence detector 4 may comprise one or more proximity sensors (e.g. a capacitive sensor) to sense movement of a detecting surface of presence detector 4.

[0115] Figs. 17A-17E schematically illustrate an automatic door system 10 comprising presence detectors that have electronic push buttons (or the like). A first presence detector 4 comprises push buttons A1 , B1 . A second presence detector 4 on an opposite side of door 8 comprises push buttons A2, B2. Fig. 17A illustrates automatic door mechanism 10 in a neutral state. Fig. 17B illustrates motion towards door 8 (e.g. compression member 109 engages push button B1 ). Fig. 17C illustrates motion away from door 8 (e.g. compression member 101 engages push button A2). Fig. 17D illustrates motion towards door 8 on either side of door 8 (e.g. a first compression member 109 engages push button B1 on a first side of door 8 and a second compression member 109 engages push button B2 on a second side of door 8). Fig. 17E illustrates motion towards door 8 on one side of door 8 and motion away from door 8 on the other side of door 8 (e.g. compression member 109 engages push button B1 on one side of door 8 and compression member 101 engages push button A2 on the other side of door 8). As described elsewhere herein, in some embodiments automatic door mechanism 10 is configured to actuate opening of door 8 if motion towards door 8 is sensed (even if motion away from door 8 is concurrently sensed). [0116] In some embodiments (as shown in example Fig. 18) push buttons A1 ,

B1 (e.g. electrical connection points) are arranged laterally (as opposed to e.g. vertically) under plate 5 of a presence detector 4. In such embodiments lateral movement of plate 5 actuates lateral movement (or generally lateral movement) of a lever system 1000 (e.g. an end of lever system 1000 comes into contact with push button A1 or B1 depending on what direction lever system 1000 moves in). In some embodiments lever system 1000 moves in the same direction as plate 5. In some embodiments lever system 1000 moves in the opposite direction of plate 5. The exemplary embodiment illustrated in Fig. 18 may, for example, replace an embodiment comprising a single fluid filled reservoir.

[0117] In some embodiments, presence detector 4 is replaced with a presence detector 300 as shown in Figs. 9 to 9B. In such embodiments, lever system 20 is replaced with chamber system 320.

[0118] Fig. 9 illustrates an exemplary embodiment of a presence detector 300 in its neutral (i.e. inactive) state. Presence detector 300 includes plate 305 vertically supported by springs 366A, 366B and transversely supported by springs 364A, 364B. Sensitivity of presence detector 300 is configurable, for example, by varying spring constants of springs 364A, 364B, 366A and/or 366B. In a preferred embodiment, springs 364A, 364B, 366A and 366B are substantially uncompressed in a neutral state of presence detector 300.

[0119] Chamber system 320 includes chambers 322, 326 filled with an actuating fluid 380. Actuating fluid 380 may, for example, have a higher viscosity than fluid 12. Chambers 322, 326 are compressible and may include an impermeable membrane. Compression of chambers 322 supplies actuating fluid 380 to actuating bladder 304 and uncompressing chambers 322 returns fluid 380 to chambers 322. Likewise, compression of chambers 326 supplies actuating fluid 380 to actuating bladder 308 and uncompressing chambers 326 returns fluid 380 to chambers 326.

[0120] Reservoirs 302, 306 are filled with fluid 12. Reservoirs 302, 306 may be contained within actuating bladders 304, 308 respectively. Reservoirs 302, 306 may be functionally equivalent to, and have the same mechanical and material properties as, reservoirs 102, 106 described herein. Reservoirs 302, 306 include line connects 303, 307 respectively. Line connects 303, 307 carry fluid 12 into and/or out of reservoirs 302, 306 respectively. Reservoir 302 is fluidly isolated from reservoir 306. [0121] In such embodiments, fluid lines 1 1 A, 1 1 B are removably coupled to line connects 303, 307. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 303 and fluid lines 1 1 B are removably coupled to line connect 307. In some embodiments, fluid lines 1 1 B are removably coupled to line connect 303 and fluid lines 1 1 A are removably coupled to line connect 307.

[0122] Supplying actuating fluid 380 to actuating bladders 304, 308 raises reservoirs 302, 306 respectively and engages reservoirs 302, 306 respectively with compression members 301 , 309 respectively.

[0123] Plate 305 includes knobs 312, 314, 316. In a neutral state of presence detector 300, knobs 312, 314, 316 rest on peaks 312C, 314C, 316C respectively. In such state, chambers 322, 326 are not compressed.

[0124] Momentum from motion of an object towards door 8 in direction X3 on an upper surface of plate 305, for example, moves plate 305 horizontally towards door 8 and downwards towards bottom support 360 as shown in Fig. 9A. Knobs 312, 314, 316 engage with, and compress, chambers 326. Chambers 326 supply actuating fluid 380 to actuating bladder 308 raising reservoir 306 towards compression member 309. Reservoir 306 engages compression member 309 displacing fluid 12 contained within reservoir 306 to hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 306 actuates opening of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 302.

[0125] Conversely, momentum from motion of an object away from door 8 in direction Y3 on an upper surface of plate 305, for example, moves plate 305 horizontally away from door 8 and downwards towards bottom support 360 as shown in Fig. 9B. Knobs 312, 314, 316 engage with, and compress, chambers 322. Chambers 322 supply actuating fluid 380 to actuating bladder 304 raising reservoir 302 towards compression member 301 . Reservoir 306 engages compression member 301 displacing fluid 12 contained within reservoir 302 to hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 302 actuates closing of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 306.

[0126] Horizontal movement of plate 305 in direction X3 compresses spring 364A while horizontal movement of plate 305 in direction Y3 compresses spring 364B. Downward movement of plate 305 towards bottom support 360 compresses springs 366A, 366B. Depending on an object’s weight, plate 305 rests on or above bottom support 360. Upon an object’s weight no longer being exerted on an upper surface of plate 305, springs 364A, 364B, 366A and/or 366B return plate 305 to its neutral position.

[0127] In an alternative embodiment of presence detector 300, chambers 322, 326 are configured such that motion in direction X3 raises reservoir 302 to actuate opening of door 8 while motion in direction Y3 raises reservoir 306 to actuate closing of door 8.

[0128] Upon chambers 322 or 326 no longer being compressed, reservoirs 302 or 306 respectively are lowered returning actuating fluid 380 from actuating bladders 304 or 308 respectively to chambers 322 or 326 respectively. In some

embodiments, gravitational forces lower reservoirs 302 or 306.

[0129] In another embodiment, presence detector 4 is replaced with a presence detector 400 as shown in Figs. 10 to 10B.

[0130] Fig. 10 illustrates a presence detector 400 in its neutral (i.e. inactive) state. Presence detector 400 includes plate 405, protruding compression member 401 and reservoirs 402, 406. Plate 405 is vertically supported by springs 466A,

466B and horizontally biased by springs 464A, 464B. Sensitivity of presence detector 400 is configurable, for example, by varying spring constants of springs 464A, 464B, 466A and/or 466B. In a preferred embodiment, springs 464A, 464B, 466A and 466B have spring constants such that springs 464A, 464B, 466A and 466B are substantially uncompressed in presence detector 400’s neutral state.

[0131] Reservoirs 402, 406 are filled with fluid 12 and are positioned within a cavity 470 in bottom support 460. Reservoirs 402, 406 are functionally equivalent to, and have the same mechanical and material properties as, reservoirs 102, 106 described herein. Reservoirs 402, 406 include line connects 403, 407 respectively. Line connects 403, 407 carry fluid 12 into and/or out of reservoirs 402, 406 respectively. Reservoir 402 is fluidly isolated from reservoir 406.

[0132] In such embodiments, fluid lines 1 1 A, 1 1 B are removably coupled to line connects 403, 407. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 403 and fluid lines 1 1 B are removably coupled to line connect 407. In some embodiments, fluid lines 1 1 B are removably coupled to line connect 403 and fluid lines 1 1 A are removably coupled to line connect 407.

[0133] Protruding compression member 401 mounted to a lower surface of plate 405 is semi-cylindrical and extends along plate 405 along a plane that is

perpendicular to an upper surface of plate 405. In a preferred embodiment, reservoirs 402, 406 mirror the shape of protruding compression member 401 . In a neutral state of presence detector 400, protruding compression member 401 rests above reservoirs 402, 406. In a preferred embodiment, protruding compression member 401 is centered to rest such that a span of protruding compression member 401 overhanging reservoir 402 is equal to a span of protruding compression member 401 overhanging reservoir 406.

[0134] Momentum from motion of an object towards door 8 in direction X4 on an upper surface of plate 405, for example, moves plate 405 horizontally towards door 8 and downwards towards upper surface 460B of bottom support 460 as shown in Fig. 10A. Protruding compression member 401 engages with, and compresses, reservoir 406 displacing fluid 12 contained within reservoir 406 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 406 actuates opening of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 402.

[0135] Conversely, momentum from motion of an object away from door 8 in direction Y4 on an upper surface of plate 405 moves plate 405, for example, horizontally away from door 8 and downwards towards upper surface 460B of bottom support 460 as shown in Fig. 10B. Protruding compression member 401 engages with, and compresses, reservoir 402 displacing fluid 12 contained within reservoir 402 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 402 actuates closing of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 406.

[0136] Horizontal movement of plate 405 in direction X4 compresses spring 464A while horizontal movement of plate 405 in direction Y4 compresses spring 464B. Downward movement of plate 405 towards upper surface 460B compresses springs 466A, 466B. Depending on an object’s weight, plate 405 rests on or above upper surface 460B. Where an object’s weight is lower than upward spring forces exerted on plate 405 by springs 466A, 466B, plate 405 rests above upper surface 460B. Where an object’s weight is equal to or higher than upward spring forces exerted on plate 405 by springs 466A, 466B, plate 405 rests on upper surface 460B. Upon an object’s weight no longer being exerted on an upper surface of plate 405, springs 464A, 464B, 466A and/or 466B may return plate 405 to its neutral position.

[0137] In some embodiments, presence detector 400 is replaced with presence detector 400A as illustrated in Figs. 10C to 10E. Presence detector 400A is identical to presence detector 400 with the exception that presence detector 400A comprises a plurality (two or more) of compression members 401 , a plurality (two or more) of reservoirs 402 and a plurality (two or more) of reservoirs 406.

[0138] Fig. 10C illustrates presence detector 400A in its neutral (i.e. inactive state). Fig. 10D illustrates presence detector 400A activated to open door 8. Fig.

10E illustrates presence detector 400A activated to close door 8.

[0139] In some embodiments, compression member(s) 401 of presence detectors 400 or 400A have triangular cross-sections. In such embodiments, reservoir(s) 402, 406 may also, for example, have triangular cross-sections.

[0140] In preferred embodiments plate 405 of presence detector 400 and/or 400A is replaced with the dual plate mechanism (e.g. plate 105T and 105B) described elsewhere herein. In some embodiments presence detector 400 and/or 400A comprises the lever system illustrated in Fig. 7. In some embodiments reservoirs 402, 406 move together with the lever system (e.g. by gliding along a track, bottom surface of the presence detector, etc. as described elsewhere herein). In some embodiments presence detector 400 and/or 400A comprise one or more friction reducing members described elsewhere herein (e.g. wheels 178A, 178B). In some embodiments movement of the lever system aligns a fluid filled reservoir with a compression member 401 .

[0141] In another embodiment, presence detector 4 is replaced with a presence detector 500 as illustrated in Figs. 1 1 to 1 1 B.

[0142] Fig. 1 1 illustrates a presence detector 500 in its neutral (i.e. inactive) state. Presence detector 500 includes plate 505 and pluralities of reservoirs 502, 506. In a neutral state of presence detector 500, plate 505 is vertically supported by springs 566A, 566B and horizontally biased by springs 564A, 564B. Sensitivity of presence detector 500 may, for example, be calibrated by varying spring constants of springs 564A, 564B, 566A and/or 566B. In a preferred embodiment, springs 564A, 564B, 566A and 566B have spring constants such that springs 564A, 564B, 566A and 566B are substantially uncompressed in presence detector 500’s neutral state.

[0143] Reservoirs 502, 506 are filled with fluid 12 and are positioned within cavities 570 of bottom support 560. Reservoirs 502, 506 are functionally equivalent to, and have the same mechanical and material properties as, reservoirs 102, 106 described herein. Reservoirs 502, 506 include line connects 503, 507 respectively. Line connects 503, 507 carry fluid 12 into and/or out of reservoirs 502, 506 respectively. Reservoirs 502 are fluidly isolated from reservoirs 506.

[0144] Fluid lines 1 1 A, 1 1 B of automatic door mechanism 10 are removably coupled to line connects 503, 507. In some embodiments, fluid lines 1 1A are removably coupled to line connects 503 and fluid lines 1 1 B are removably coupled to line connects 507. In some embodiments, fluid lines 1 1 B are removably coupled to line connects 503 and fluid lines 1 1 A are removably coupled to line connects 507.

[0145] Presence detector 500 comprises one or more levers 510 pivotally coupled at a first end to a lower surface of plate 505 and at a second end distal from the first end to bottom support structure 560. Levers 510 may, for example, be pivotally coupled to plate 505 using mounts 509. Levers 510 may, for example, be pivotally coupled to bottom support structure 560 using mounts 51 1 . In some embodiments, a length of one or more levers 509 is equal to a length of one or more reservoirs 502, 506.

[0146] Momentum from motion of an object towards door 8 in direction X5 on an upper surface of plate 505, for example, moves plate 505 horizontally towards door 8 and downwards towards upper surface 560B of bottom support 560 as shown in Fig. 1 1 A. Movement of plate 505 in direction X5 torques one or more levers 510 clockwise around mounts 509, 51 1 . When torqued clockwise, one or more levers 510 engage with, and compress, one or more reservoirs 506 displacing fluid 12 contained within reservoirs 506 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoirs 506 actuates opening of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoirs 502. [0147] Conversely, momentum from motion of an object away from door 8 in direction Y5 on an upper surface of plate 505, for example, moves plate 505 horizontally away from door 8 and downwards towards upper surface 560B of bottom support 560 as shown in Fig. 1 1 B. Movement of plate 505 in direction Y5 torques one or more levers 510 counterclockwise around mounts 509, 51 1 . When torqued counterclockwise, one or more levers 510 engage with, and compress, one or more reservoirs 502 displacing fluid 12 contained within reservoirs 502 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoirs 502 actuates closing of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoirs 506.

[0148] Horizontal movement of plate 505 in direction X5 compresses spring 564A while transverse movement of plate 505 in direction Y5 compresses spring 564B. Downward movement of plate 505 towards upper surface 560B compresses springs 566A, 566B. Upon an object’s weight no longer being exerted on an upper surface of plate 505, springs 564A, 564B, 566A and/or 566B return plate 505 to its neutral position.

[0149] In a yet further embodiment, presence detector 4 is replaced with a presence detector 600 as shown in Figs. 12 to 12B.

[0150] An exemplary embodiment of presence detector 600 in its neutral (i.e. inactive) state is shown in Fig. 12. Presence detector 600 includes plate 605 vertically supported by springs 666A, 666B and horizontally biased by springs 664A, 664B. Arms 620, 630 are pivotally coupled to plate 605 using mounts 612, 614 respectively. Rollers 624, 634 are pivotally coupled to arms 620, 630 respectively. Movement of plate 605 pivots arms 620, 630 around mounts 612, 614 respectively and initiates gliding of rollers 624, 634 along track 650.

[0151] Track 650 has an arcuate trajectory. In some embodiments, track 650 may, for example, be a semi-circle. In some embodiments, track 650 may, for example, be semi-elliptical. Rollers 624, 634 may, for example, be wheels, bearings, cylindrical rods or the like.

[0152] Pads 622, 632 are fixedly attached to ends 620A, 630A respectively of arms 620, 630 respectively. In an example neutral state of presence detector 600, plate 605 is positioned for a distance 616 between pad 622 and reservoir 602 to be equivalent to a distance 618 between pad 632 and reservoir 606.

[0153] Reservoirs 602, 606 are filled with fluid 12 and are positioned at opposing ends 650A, 650B of track 650. Reservoirs 602, 606 are functionally equivalent to, and have the same mechanical and material properties as, reservoirs 102, 106 described herein. Reservoirs 602, 606 include line connects 603, 607 respectively. Line connects 603, 607 carry fluid 12 into and/or out of reservoirs 602, 606 respectively. Reservoir 602 is fluidly isolated from reservoir 606.

[0154] In such embodiments, fluid lines 1 1 A, 1 1 B are removably coupled to line connects 603, 607. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 603 and fluid lines 1 1 B are removably coupled to line connect 607. In some embodiments, fluid lines 1 1 B are removably coupled to line connect 603 and fluid lines 1 1 A are removably coupled to line connect 607.

[0155] Momentum from motion of an object towards door 8 in direction X6 on an upper surface of plate 605, for example, moves plate 605 horizontally towards door 8 and downwards towards track 650 as shown in Fig. 12A. Arms 620, 630 are pivoted clockwise around mounts 612, 614 respectively. Roller 624 glides along track 650 away from end 650A while roller 634 glides along track 650 towards end 650B. Pad 632 engages with, and compresses, reservoir 606 displacing fluid 12 contained within reservoir 606 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 606 actuates opening of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 602.

[0156] Conversely, momentum from motion of an object away from door 8 in direction Y6 on an upper surface of plate 605 for example, moves plate 605 horizontally away from door 8 and downwards towards track 650 as shown in Fig. 12B. Arms 620, 630 are pivoted counterclockwise around mounts 612, 614 respectively. Roller 634 glides along track 650 away from end 650B while roller 624 glides along track 650 towards end 650A. Pad 622 engages with, and compresses, reservoir 602 displacing fluid 12 contained within reservoir 602 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 602 actuates closing of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 606. [0157] Transverse movement of plate 605 in direction X6 compresses spring 664A while transverse movement of plate 605 in direction Y6 compresses spring 664B. Downward movement of plate 605 towards track 650 compresses springs 666A, 666B. Upon an object’s weight no longer being exerted on an upper surface of plate 605, springs 664A, 664B, 666A and/or 666B return plate 605 to its neutral position.

[0158] In some embodiments, presence detector 4 is replaced with a presence detector 700 as shown in Figs. 13 to 13B.

[0159] Fig. 13 illustrates an example embodiment of a presence detector 700 in its neutral (i.e. inactive) state. Presence detector 700 includes plate 705 vertically supported by springs 766A, 766B and horizontally biased by springs 764A, 764B. Sensitivity of presence detector 700 is configurable, for example, by varying constants of springs 764A, 764B, 766A and/or 766B. In a preferred embodiment, springs 764A, 764B, 766A and 766B are substantially uncompressed in a neutral state of presence detector 700.

[0160] Below a lower surface of plate 705, presence detector 700 includes fluid filled reservoirs 702, 706. Reservoirs 702, 706 are functionally equivalent to, and have the same mechanical and material properties as, reservoirs 102, 106 described herein. Reservoirs 702, 706 include line connects 703, 707 respectively. Line connects 703, 707 carry fluid 12 into and/or out of reservoirs 702, 706 respectively. Reservoir 702 is fluidly isolated from reservoir 706.

[0161] In such embodiments, fluid lines 1 1 A, 1 1 B are removably coupled to line connects 703, 707. In some embodiments, fluid lines 1 1 A are removably coupled to line connect 703 and fluid lines 1 1 B are removably coupled to line connect 707. In some embodiments, fluid lines 1 1 B are removably coupled to line connect 703 and fluid lines 1 1 A are removably coupled to line connect 707.

[0162] Bottom support 760 of presence detector 700 includes horse-shoe shaped supporting guides 750. Supporting guides 750 vertically support plate 705 and guide movement of plate 705. Members 752, 754, 756 mounted to a lower surface of plate 705 glide within supporting guides 750. Members 752, 754, 756 may be mounted to plate 705 using any mounting technique described herein. In a neutral state of presence detector 700, members 752, 754, 756 rest at a vertical apex of supporting guides 750. In some embodiments, supporting guides 750 may be triangular. In some embodiments the angle of the apex of the triangle is relatively small (e.g. less than or equal to 20°). In some embodiments the angle of the triangle is larger (e.g. more than 20°).

[0163] Momentum from motion of an object towards door 8 in direction X7 on an upper surface of plate 705, for example, moves plate 705 horizontally towards door 8 and downwards towards bottom support 760 as shown in Fig. 13A. Members 752, 754, 756 glide along supporting guides 750 towards door 8. Members 754, 756 engage levers 782, 786 respectively pivoting lever 782 counterclockwise around pivot support 746 and lever 786 clockwise around pivot support 748.

Counterclockwise and clockwise pivoting of levers 782, 786 respectively raises platform 784 engaging reservoir 706 with compression member 709. Engagement of reservoir 706 with compression member 709 compresses reservoir 706 displacing fluid 12 from reservoir 706 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 706 actuates opening of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 702.

[0164] Conversely, momentum from motion of an object away from door 8 in direction Y7 on an upper surface of plate 705, for example, moves plate 705 transversely away from door 8 and downwards towards bottom support 760 as shown in Fig. 13B. Members 752, 754, 756 glide along supporting guides 750 away from door 8. Members 752, 756 engage levers 772, 776 respectively pivoting lever 772 counterclockwise around pivot support 742 and lever 776 clockwise around pivot support 744. Counterclockwise and clockwise pivoting of levers 772, 776 respectively raises platform 774 engaging reservoir 702 with compression member 701 . Engagement of reservoir 702 with compression member 701 compresses reservoir 702 displacing fluid 12 from reservoir 702 into hydraulic mechanism 30. Supplying fluid 12 to hydraulic mechanism 30 from reservoir 702 actuates closing of door 8 and returns fluid 12 from hydraulic mechanism 30 to reservoir 706.

[0165] In some embodiments, as illustrated in Figs. 13A and 13B, pivoting of levers 772, 776, 782 and/or 786 raises one or more of levers 772, 776, 782 and 786 above pivot supports 742, 744, 746 and/or 748 respectively. In some embodiments (not illustrated), pivoting of levers 772, 776, 782 and/or 786 does not raise one or more of levers 772, 776, 782 and 786 above pivot supports 742, 744, 746 and/or 748 respectively.

[0166] Transverse movement of plate 705 in direction X7 compresses spring 764A while horizontal movement of plate 705 in direction Y7 compresses spring 764B. Downward movement of plate 705 towards bottom support 760 compresses springs 766A, 766B. Upon an object’s weight no longer being exerted on an upper surface of plate 705, springs 764A, 764B, 766A and/or 766B return plate 705 to its neutral position.

[0167] In some embodiments, system 900 illustrated in Figs. 14A to 14C is used to delay closing of door 8.

[0168] Fig. 14A illustrates system 900 in its neutral (i.e. inactive) state. System 900 comprises an intermediary reservoir 979. Reservoir 979 may, for example, be fillable with fluid 12. System 900 may also comprise one or more means for restricting flow of fluid 12. For example, system 900 may comprise valves 981 , 983, 985 and 989. Valve 981 prevents flow of fluid 12 from, for example, reservoir 102 (described elsewhere herein) to fluid line 91 1 D while allowing flow of fluid 12 from fluid line 91 1 D to reservoir 102. Valve 983 prevents flow of fluid 12 from, for example, reservoir 979 to reservoir 102 while allowing flow of fluid 12 from reservoir 102 to reservoir 979. In some embodiments, valves 981 and 983 are commercially available check valves.

[0169] Compression of reservoir 102 filled with fluid 12 causes flow of fluid 12 from reservoir 102 to reservoir 979. Flow of fluid 12 into reservoir 979 compresses spring 979A of reservoir 979 as shown in Fig. 14B. Reservoir 102 is fluidly coupled to reservoir 979 using fluid line 91 1 A. Flow of fluid 12 from reservoir 102 to reservoir 979 causes valve 985 to close. Closing of valve 985 fluidly isolates fluid line 91 1 B from fluid line 91 1 A. For example, flow of fluid 12 in pilot line 985A may close valve 985. In some embodiments, valve 985 is a commercially available piloted shut off valve.

[0170] Upon reservoir 102 no longer being compressed (e.g. upon plate 105 returning to its neutral state), valve 985 opens allowing for flow of fluid 12 from intermediary reservoir 979 to hydraulic mechanism 30 as shown in Fig. 14C. Valve 985 may, for example, open as a result of fluid 12 no longer being present in pilot line 985A of valve 985. Upon valve 985 opening, spring 979A actuates flow of fluid 12 from intermediary reservoir 979 to fluid line 91 1 B. Flow of fluid 12 in fluid line 91 1 B actuates valve 989 to fluidly isolate fluid line 91 1 B from fluid line 91 1 D (i.e. fluid 12 in fluid line 91 1 B cannot flow back to reservoir 102 via fluid line 91 1 D). In some embodiments, valve 989 is a commercially available spring loaded check valve. Fluid line 91 1 B is fluidly coupled to hydraulic mechanism 30 using fluid lines 1 1 A or 1 1 B described elsewhere herein.

[0171] As shown in Figs. 14B and 14C, fluid 12 may, for example, flow according to illustrated arrows 900A.

[0172] The rate at which fluid 12 flows out of reservoir 979 may, for example, be varied by varying the spring constant of spring 979A.

[0173] In some embodiments, system 900 is contained within a presence detector (e.g. presence detector 4 described elsewhere herein).

[0174] In some embodiments, hydraulic mechanism 30 may be connected to fluid lines 1 1 A, 1 1 B in parallel with a pressure regulator tank. The pressure regulator tank regulates pressure of fluid 12 within fluid lines 1 1 A, 1 1 B and/or hydraulic mechanism 30. The pressure regulator tank has a fluid resistance equivalent to a threshold pressure value. If pressure exceeds the threshold value, fluid 12 flows into the pressure regulator tank reducing pressure of fluid 12 in fluid lines 1 1 A, 1 1 B and/or hydraulic mechanism 30. The threshold pressure value corresponds to a pressure value which, if exceeded, may for example result in hydraulic mechanism 30 leaking.

[0175] In some embodiments, the pressure regulator tank is equivalent to tank 61 illustrated in Fig. 15A. Tank 61 may, for example, comprise a spring 61 A used to set a threshold pressure value of tank 61 . Valves 62A, 62B, 62C may, for example, restrict flow of fluid 12 to and/or from reservoir 106. In some embodiments, valves 62A, 62B are commercially available check valves. In some embodiments, valve 62C is a commercially available spring loaded check valve. In some embodiments tank 61 and valves 62A, 62B and 62C are contained within a presence detector (e.g. a presence detector 4 described elsewhere herein). Compression of, for example, reservoir 106 resulting in a pressure of fluid 12 greater than the threshold pressure value compresses spring 61 A and results in flow of fluid 12 according to arrows 63 as shown in Fig. 15B.

[0176] In some embodiments, both system 900 described elsewhere herein and tank 61 are contained within a presence detector (e.g. a presence detector 4 described elsewhere herein) as shown in Fig. 16.

[0177] In some embodiments, fluid 12 may be replaced with a gas (not shown). In such embodiments, hydraulic mechanism 30 may better be described as a pneumatic mechanism. Pneumatic mechanism is identical to hydraulic mechanism 30 described herein with the exception that it is actuated by gas and not fluid 12. Pneumatic mechanism is interfaced with presence detectors 4 containing gas filled reservoirs. In one embodiment, supplying gas 12’ to pneumatic mechanism 30’, for example, opens door 8 while removing gas 12’ from pneumatic mechanism 30 closes door 8. In another embodiment, supplying gas 12’ to pneumatic mechanism 30’ closes door 8 while removing gas 12’ from pneumatic mechanism 30’ opens door 8. Optionally, pneumatic mechanism 30’ may include a release valve for removing gas 12’ from pneumatic mechanism 30’ directly into an environment.

[0178] In some embodiments, any reservoir discussed herein may, for example, be replaced with a plurality of reservoirs. In such embodiments, fluid lines 1 1 A and/or 1 1 B interface the plurality of reservoirs with hydraulic mechanism 30.

[0179] In some embodiments, fluid lines 1 1 A and/or 1 1 B may be removably coupled to hydraulic mechanism 30 via a directional flow control valve. In such embodiments, the directional flow control valve may, for example, be operated to disconnect fluid lines 1 1 A and/or 1 1 B from hydraulic mechanism 30. Alternatively, or in addition, the directional control valve may, for example, be operated to select how reservoirs disclosed herein (e.g. reservoirs 102, 106) are interfaced to hydraulic mechanism 30 (i.e. selecting which reservoir(s) will open door 8 and/or which reservoir(s) will close door 8).

Interpretation of Terms

[0180] Unless the context clearly requires otherwise, throughout the description and the claims: • “comprise”,“comprising”, and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”;

• “connected”,“coupled”, or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof; elements which are integrally formed may be considered to be connected or coupled;

• “herein”,“above”,“below”, and words of similar import, when used to

describe this specification, shall refer to this specification as a whole, and not to any particular portions of this specification;

• “or”, in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list; and

• the singular forms“a”,“an”, and“the” also include the meaning of any

appropriate plural forms.

[0181] Words that indicate directions such as“vertical”,“transverse”, “horizontal”,“upward”,“downward”,“forward”,� ��backward”,“inward”,“outward”, “vertical”,“left”,“right”,“front”,“back” ,“top”,“bottom”,“below”,“above”,“under”, and the like, used in this description and any accompanying claims (where present), depend on the specific orientation of the apparatus described and illustrated. The subject matter described herein may assume various alternative orientations.

Accordingly, these directional terms are not strictly defined and should not be interpreted narrowly.

[0182] Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions, and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be apparent to the skilled addressee, including variations obtained by: replacing features, elements and/or acts with equivalent features, elements and/or acts; mixing and matching of features, elements and/or acts from different embodiments; combining features, elements and/or acts from embodiments as described herein with features, elements and/or acts of other technology; and/or omitting combining features, elements and/or acts from described embodiments.

[0183] Various features are described herein as being present in“some embodiments” or“in an example embodiment”. Such features are not mandatory and may not be present in all embodiments. Embodiments of the invention may include zero, any one or any combination of two or more of such features. This is limited only to the extent that certain ones of such features are incompatible with other ones of such features in the sense that it would be impossible for a person of ordinary skill in the art to construct a practical embodiment that combines such incompatible features. Consequently, the description that“some embodiments” possess feature A and“some embodiments” possess feature B should be interpreted as an express indication that the inventors also contemplate

embodiments which combine features A and B (unless the description states otherwise or features A and B are fundamentally incompatible).

[0184] It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions, omissions, and sub-combinations as may reasonably be inferred. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.