System and Method for Capture of Random Sized Boxes by Unmanned Vehicle

CROSS-REFERENCE TO RELATED APPLICATIONS US 62/275,637 1/06/2016

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM

LISTING COMPACT DISK APPENDIX

Not Applicable

FIELD

[0001] This invention relates generally to the field of cardboard box and paper handling and more specifically to capture or grasping of random sized boxes by an unmanned vehicle.

BACKGROUND

[0002] To provide a truly automated delivery operation, whether commercial delivery, disaster relief, or search and rescue the Unmanned Autonomous Vehicle (UAV) must be able to quickly and easily grasp and hold a cardboard box with no human assistance, hold it tight enough that it will not come loose during transit, and then release the box at the destination. In order to accomplish this task, the grip unit must also be lightweight and able to grasp any size of box within a given design range.

[0003] In many delivery scenarios currently visible in the media and literature, random boxes are either placed within a plastic bin of a known size, or otherwise the lift mechanism is custom fit to their intended load, such as a pizza box within a warming cozy that is permanently affixed to the UAV. In order to accomplish random box grasping, the system must perform three tasks: First, orient the platform to the box, or vice-versa. Second, lower the platform to the height of the box. Third, grasp the box with a mechanical system capable of a wide range of adjustment and providing a grip strength which exceeds the maximum weight of the package.

BRIEF SUMMARY OF THE INVENTION

[0004] Cardboard boxes or shipping containers made primarily of paper products continue to be the simplest, least expensive, and most recyclable for shipping goods of all sorts. In order to provide delivery services via land or air Unmanned Autonomous Vehicle (UAV) a method must be determined to automatically load, grasp, and release the shipping container. This has previously been done by utilization of a specific shipping container, often plastic, that is designed specifically for the UAV's capabilities and then the box or merchandise is placed within this container. To be more economically viable, it is preferable that the UAV be equipped with a mechanism which can directly load, grasp, and release a cardboard box of random dimensions within a minimum and maximum dimension and weight specification.

[0005] In one embodiment four sets of individual but linked grip plates are part of the grip mechanism of the UAV. Each grip plate has a random distribution of small protrusions or hooks such that when the plate is pressed against the cardboard with a minimum amount of force the hooks create micro-indentations in the paper structure. Depending on the weight specification and the material of the box, these indentations may slightly puncture the outer skin of the cardboard structure or partially pierce the inner corrugated core material. It is not intended that the micro-indentations completely pierce the box as this would lead to possible contamination, water damage, or insect incursion, however in some embodiments this practice might also be allowed to significantly increase the weight carrying capability of the device.

[0006] All four plates have separate plate segments and while any combination of the plates may be deployed to grasp a particular object, in this embodiment an odd number of plates allows for simplicity of the control system with a wide range of grip configurations. In one embodiment the grip pads may be rectangular, in other embodiments without limitation they may be round or elliptical. The sizes of the pads may be equal across the system, or may vary by a constant, multiplicative, exponential or other differential. For example without limitation, five plates may be deployed in one embodiment with the relative sizes of the pads at 1 in the center, 2, and 4 in the outer groups. This allows grasping of very small to very large boxes. In another embodiment more than one row of grasping plate might be implemented. To one skilled in the art it would be seen that adjusting the width dimension of the plates would not alter the intention of this invention, and that multiple rows would be functionally equivalent to modifying the Y dimension. Different plates may also have different sizes, types, or methodology of micro- indentation grip.

[0007] When grasping a package that is smaller than the width of the larger plates, the two smaller plates would make complete contact but the larger plates might be stopped by the sides of the smaller plates if the package dimension was also small in that direction. For this reason the plates are segmented such that at least one plate segment on each of the four sides will make contact with the package.

[0008] The Z dimension or height of the package can be met in a number of ways. In one embodiment the entire UAV platform is raised or lowered on its landing gear, support mechanism, or by altering hover altitude. In another embodiment the Grasping Mechanism (GM) itself is raised or lowered in relation to the body of the UAV.

[0009] In some instances both mechanisms or other height changing methods might be used. The UAV may use its lower optical or proximity sensors to detect the dimensionality of the package including its height, or it may have another set of optical or proximity sensors implemented specifically for this purpose.

[0010] Once the height and the orientation of the package is established by sensors, or relayed to the UAV from external sensors, the UAV maneuvers into position over the package. This maneuver may be done via remote or autonomous controlled flight or through wheeled, tracked, or other surface, sub-surface, or flat surface mechanical means.

[0011] Once in position the vehicle body or the grasping mechanism or both traverse to match the height of the package and sensors on the grasping mechanism detect contact. The segmented grasping plates are then extended to make contact with the package and press inward with sufficient force to cause the micro-indentations. The plates are then locked into place. In one embodiment a spring tensioning system allows only the correct force to be applied to the box independent of the mechanical actuator that may be causing movement of the plates as they deploy.

[0012] Once the plates are locked into place, the grasping mechanism applies tension against the top of the box, either by pulling the box up against the top of the mechanism with the plate arms or by a pressure plate at the top of the grasping mechanism pressing down against the top of the box or both. This pre-tensioning process provides an empirical measurement that the box has been grasped with sufficient adhesion that it is not likely to pull loose during flight or travel operations.

[0013] The amount of tension may be varied by the size of the box, the weight of the box and materials within, information about the box relayed with the shipping information, or the material of the box itself. In performing this action the UAV is also able to accurately measure the weight of the package and center of gravity so that proper flight dynamics may be calculated. If the box is too heavy, or it breaks loose during this procedure, the UAV may declare an error and move to a safe offset location so that the box may be removed and another scheduled for shipment.

[0014] In another embodiment the UAV may attempt to move the box itself to another location for further processing. Upon completion of the test most if not all of the pressure on the top of the box is released so that box is not overly stressed during flight. Some pressure might remain to increase stability. The UAV may also need to attempt a lift of the package by some small amount to determine the center of gravity before flight phase of the delivery is engaged.

[0015] In one embodiment the articulated landing struts which allow the UAV to adjust its height relative to the package are engaged at the beginning of flight to grasp the underside of the box providing additional safety and security for the package. In another embodiment a small chain, cable, or other flexible media is strung from one side of the grasping mechanism, through two of the feet, and then back to the other side of the mechanism. As flight begins, the articulated landing struts can maneuver the cables under the box and the grasping mechanism can then tighten or cinch the cable to increase stability and safety.

[0016] In the event that the entire grasping mechanism breaks loose from the UAV body, a safety chain, cable, or tether may be employed as a backup restraint, or a parachute, air bag, or other safety mechanism may be deployed to mitigate the terminal velocity and impact force of the falling package. The parachute or other safety device may be attached to the box by a separate attachment method not directly attached to or dissociated from the grasp mechanism such that if the box separates from the grasp mechanism the safety device is deployed. In an emergency the package may be jettisoned such that it has a safe controlled descent but allowing the UAV more maneuverability and lift to try to correct for the emergency.

[0017] Once the destination is reached, the process is reversed. The UAV lands or hovers at a specific altitude above landing platform and the box is lowered until it makes contact. The grasp plates are then moved away from the package removing the pressure on the micro-indentations and the box is released. In one embodiment the direction of movement for removal of the plate is normal to the box surface. In another embodiment the grasp plate may need to move down and away from the box surface to properly disengage without damaging the box surface or structure further. A CAM structure or similar mechanical actuator would suffice to create more complex movement.

[0018] In one embodiment the grasp mechanism contains a central processing unit or hardware control system and electronic sensors such as but not limited to proximity sensors, optical sensors, and weight sensors. The central processor unit communicates with and receives instructions from the primary control unit of the UAV. Communication may include but not be limited to size, orientation, and weight of the package, error conditions, movement instructions to the UAV to accomplish engagement with the package, and status information such as grasp complete. The central processing unit would execute instructions and protocols to safely grasp, measure, and release the package.

[0019] In another embodiment the sensors may be part of the UAV itself, and only power and simple mechanical actuator controls are implemented in the grasp mechanism itself. In another embodiment a hardware state machine may be implemented rather than software to execute all functions of the grasping mechanism. In another embodiment a combination of techniques may be utilized.

BRIEF DESCRIPTION OF DRAWINGS [0020] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The use of the same reference numbers in different figures indicates similar or identical components or features.

[0021] The novel features believed characteristic of the illustrative embodiments are set forth in the appended claims. The illustrative embodiments, however, as well as a preferred mode of use, further objectives, and features thereof will best be understood by reference to the following detailed description of illustrative embodiments of the present disclosure when read in conjunction with the accompanying drawings, wherein:

[0022] FIG. 1 shows an overall depiction of the box grasp mechanism.

[0023] FIG. 2 depicts the segmented grasp plate mechanism.

[0024] FIG. 3 depicts a close-up view of the micro-indentation grasp plate.

DETAILED DESCRIPTION OF INVENTION

[0025] The following detailed description illustrates embodiments of the invention by way of example and not by way of limitation. The description clearly enables one skilled in the art to make and use the disclosure, describes several embodiments, adaptations, variations,

alternatives, and use of the disclosure, including what is currently believed to be the best mode of carrying out the disclosure. The disclosure is described as applied to an exemplary embodiment namely, systems and methods for the creation of a safe vehicle control system. However, it is contemplated that this disclosure has general application to vehicle management systems in industrial, commercial, military, and residential applications.

[0026] As used herein, an element or step recited in the singular and preceded with the word "a" or "an" should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to "one embodiment" of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

[0027] Referring now to the invention in more detail, FIG. 1 depicts one embodiment of the grasp mechanism which would be attached to the underside of an unmanned vehicle affixed to package 100. The main body of the mechanism 110 contains the actuators for the grasp plates 120 and any electronic sensors and processing units required in the implementation. In this embodiment articulated landing struts 130 are shown in their landing position.

[0028] In one embodiment the legs simply rotate from vertical to nearly horizontal to allow for package height. The "feet" or the portion of the strut that contacts the landing surface 140 may include rollers, balls, or low friction materials to allow the landing struts to rotate to a given angle without frictional stress with the landing pad material. The grasp plate segments 120 150 are shown in this embodiment as hinged at the top of the Grasping Mechanism (GM) to provide grasping reach for larger packages than would fit under the grasping mechanism itself. This allows the grasping mechanism to be as small and lightweight as possible for a given

specification of size and weight.

[0029] A safety cable may be implemented to attach the grasp mechanism to the UAV frame, and a parachute may be embedded in the top of the grasp mechanism to deploy in the event that the grasp mechanism breaks loose from the airframe and safety cable. The system is designed such that the grasp mechanism holds onto the package under most conditions and if severe platform damage occurs the package may be jettisoned to provide safe terminal landing of the package and greater maneuverability for the platform. Tracking transponders may be included in the mechanism to locate it in the event of separation.

[0030] One or more pressure pads 160 are implemented between the package and the bottom of the main grasp mechanism to apply downward pressure against the package to test the grip panels.

[0031] Cooperation between the grasp mechanism and the UAV control system may be implemented as UAV-controlled or Cooperative. In UAV controlled systems the GM may have limited processing power or simple actuator controls and the UAV instructs the GM to perform each motion and task. Sensors are either directly connected to the UAV control system or connected as a secondary bus or link. The UAV control system therefore performs all state machine and protocol operations to grasp, test, hold, and release the package throughout the mission. [0032] In Cooperative control systems, the grasp mechanism contains sufficient processing logic to perform all functional requirements but the UAV controls the height of the body, movement, and landing gear. A communications link and protocol provide communication of status and other information between the two systems. These protocols may include such as but not limited to Package Detected, Orientation Request, Height Request, Grasp In Process, Grasp Complete, Error Code, Package Addressing, Weight, and Dimension Reading. Messages sent from the UAV to the GM might include but not be limited to System Initialization, Begin Grasp Process and Release.

[0033] In another embodiment both the UAV and GM may be controlled by an external and/or remote control either human or autonomous.

[0034] While in flight the landing struts may fold against or into the UAV flight body or may stay outboard. The grip panels may fold into or away from the main grasp mechanism to minimize drag, or may be implemented to fold into the grasp mechanism itself. With a package stowed under the body, the UAV is not aerodynamic and uses more fuel and flies slower than the UAV would without the package. In one embodiment this lack of aerodynamics is taken as a fixed cost and few measures if any are taken to improve the air resistance of the airframe. In other embodiments the UAV may be a road or surface vehicle and aerodynamics may not be an issue.

[0035] In another embodiment the UAV landing struts may be part of an aerodynamic cowling or body structure which could open to receive the package, and then upon liftoff close around the package providing a much more secure and aerodynamically viable cruise configuration.

[0036] FIG. 2 depicts the relationship of the grasp plate sections when the package is smaller than the grasp area in at least one dimension. The box 200 is shown in the center. In this embodiment it is shown as being long in the X direction and short in Y. In the X direction all three grip plate segments on the front and back 210 220 230 make contact with the box. In the Y direction only one plate left and right 240 250 make contact but any other plates that might be implemented in the platform (not shown) are not deployed.

[0037] In other embodiments the spring or other tensioning mechanism may be included as part of the actuator or other arrangement without altering the intent of this invention. In another embodiment the selection of which plate segments are used and which are left inactive may be made by the processing control unit (either within the UAV or the grasp mechanism) once the dimensions and orientation of the package is known. Solenoids or other electromechanical actuators or motor controls or a purely mechanical system derived by sensors at the sides of the grasp mechanism which detect the box sides could be used.

[0038] The result of this embodiment is that only the grasp plate segments which will fit the package are actuated. In one embodiment the height of the platform relative to the package is adjusted by simply spreading the legs apart, while in this depicted embodiment an additional hinge articulation is shown 260 which allows the legs to fold to a greater extent.

[0039] FIG 3. Shows an exemplar of several different forms of micro-indentation awl. The awl can be characterized primarily by its depth 300 width 310 length 320 and angle of incidence 330. In one embodiment 340 the awl is semicircular in shape at the top and tapering to flush with the plate surface at the bottom.

[0040] In another example 350 the awl is triangular in shape and tapers to flush at the bottom. In another example the awl is a cylinder 360 that has been tack welded to the surface at an angle such that the angle of incidence of the awl is equal to the angle of the wire when welded. In another example the same shapes as 340 and 350 may be implemented as shown in 360 where the top of the awl has an angle of incidence of less than 90 degrees.

[0041] In all cases, the awls may be formed on the grasp plate in random and/or structured locations. Structures may include but not be limited to radial, row and column, mathematical, or fractal locations. The dimensions of awl definitions 300 310 320 330 may vary from

implementation to implementation due to the materials and weights specified for the grip system. For example, a dense random awl structure similar to sandpaper may be adequate for one system, while another might require just a few heavy grip awls with high angle of incidence.

[0042] In another embodiment the packaging may be of a tougher material such as plastic or even metals, and it may have the micro-indentations already molded into the sides. In these instances aggressive indentations may be molded into the package and the grip plate such that many potential mating locations are possible with high degree of grip strength. In this embodiment a structured location implementation would allow very high grip strength while maintaining relatively random location of the grip pads.

[0043] In general, the protrusion distance of the awl 300 would be equal to the outer skin depth of the cardboard, or the outer skin plus corregation depth in another instance. A protrusion distance greater than that would completely pierce the cardboard box, which could have negative consequences but may be required for extremely heavy loads.

[0044] Similarly an angle on incidence of 90 degrees provides the least damage to the box and easy release, but may not provide enough stability for some loads. In another embodiment actual sandpaper may be used instead of the fabricated grip plates. Similar results could be obtained with sandpaper with small grit such as 100 to large grit such as 40. While less expensive than a fabricated grip plated, sandpaper would wear much more quickly and require repeated maintenance.

[0045] In one embodiment the system which is scheduling the shipments, either human-run or automated, may have as part of the package shipping specification the address, dimensions, weight, and packaging type given at time of package submission to the network. This information can then be used to select and queue the appropriate UAV for the package, and that information can also be used by the UAV to set, for example without limitation, tensioning parameters for the grasp mechanism. In one embodiment the tensioning and other parameters are simply defined in the hardware or adjustable but fixed settings, in other embodiments some parameters may be set by the central processing unit in the grasp mechanism.

[0046] While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention. Further, different illustrative embodiments may provide different benefits as compared to other illustrative embodiments. The embodiment or embodiments selected are chosen and described in order to best explain the principles of the embodiments, the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.

[0047] The flowcharts and block diagrams described herein illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various illustrative embodiments. In this regard, each block in the flowcharts or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function or functions. It should also be noted that, in some alternative implementations, the functions noted in a block may occur out of the order noted in the figures. For example, the functions of two blocks shown in succession may be executed substantially concurrently, or the functions of the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.