Computer Mouse with Rotational Input

Field of Invention

The invention pertains to a computer mouse and more particularly to an improved rotational mouse which provides additional and enhanced functions as compared to previously disclosed rotational mice.

Background of the Invention

A computer mouse is a common form of input device in which the movement of the mouse in conjunction with switches and optional secondary input devices such as scroll wheels and trackballs may be used to control pointer movement and various other functions on a host computer. A typical mouse allows two dimensions of lateral input corresponding to horizontal and vertical movement relative to a surface such as a desktop in addition to one or more secondary input dimensions from scroll wheels or a trackball.

US patent application 20040104892 entitled 'Computer Mouse with Magnetic Orientation Features' describes a wireless rotational computer mouse which provides three distinct primary dimensions of input by employing a solid state compassing device in addition to an X-Y sensor, allowing it to be sensitive to rotational input as well as lateral input.

A standard scrolling computer mouse of the prior art typically features a clickable scroll wheel which functions as a third button in addition to left and right buttons. The function of this button depends on the software applications in use on the host computer.

It is a limitation of the rotational mouse disclosed in US patent application 20040104892 that only two button functions are provided, being a 'push' button and 'squeeze' buttons corresponding to left and right button functions on a typical mouse.

It is an advantage to provide a third button on a rotational mouse to allow additional input functions and to ensure compatibility with software applications that have been designed to take advantage of a 3-button scrolling mouse. It is also an advantage to provide a dimple feature on the top of the mouse to aid in the rotation of the mouse using a fingertip.

It is a further limitation of the rotational mouse disclosed in US patent application 20040104892 that the 'squeeze' buttons arranged around the perimeter of the mouse have a limited area of activation due to the physical arrangement of the shell and the perimeter switches. It is an advantage to provide an improved mechanism for transferring activation force from the flexible outer shell of the mouse to the switches by the inclusion of rigid side buttons with location features.

It is a limitation of a solid state compass based on a 2-axis linear sensor as employed in the rotational mouse disclosed in US patent application 20040104892 that it will only work accurately when the sensors are maintained at a particular angle of tilt with respect to the magnetic field being measured. For example, if the mouse is used on a fixed desktop with a horizontal flat surface then the compass will work accurately, but if the mouse is used on a moveable surface such as an object held in the user's lap then inaccuracies may arise. It is therefore an advantage to provide a third axis, or 'tilt' sensor by which the angle of tilt may be measured and used to compensate the inputs from the lateral 2-axis linear magnetic sensor.

A standard mouse of the prior art typically features a number of buttons that are differentiated in function by their position on the body of the mouse and hence their correspondence to the fingers of the user while the mouse is in use. For example it is common to employ a 'left mouse button' corresponding to the index finger in addition to a 'right mouse button' corresponding to the middle finger with specific software related functions attributed to each button.

In the case of a rotational mouse this approach is not practical since the position of any particular physical burton relative to the fingers of the user will change depending on the angle of rotation of the mouse. In the rotational mouse previously disclosed in US patent application 20040104892 the solution to this problem is to employ a 'push' top button in addition to 'squeeze' perimeter buttons, the operation of which are not sensitive to the angle of rotation of the mouse.

It is advantageous in a rotational mouse to provide radially arranged buttons whereby the function of the buttons is sensitive to the orientation of the mouse as determined by the compassing device, so that the function of each button is connected to its position relative to the fingers of the user and not to its position relative to the mouse. In this way additional button functions can be provided.

Since a mouse which is wireless must provide its own source of power, it is generally the case that one or more batteries are employed in such a device.

While it is sometimes practical to provide access for the removal and replacement of batteries, it is advantageous for the sake of convenience to provide a rechargeable battery and a means for recharging the battery without the need to remove it from the mouse. This is especially the case when the physical design of the mouse results in restricted access to the internal spaces of the mouse.

A common and convenient means for transmitting charging power to a mouse is to provide a charging station in which the mouse rests whereby the shape of the charging station matches a particular part of the body of the mouse enabling the alignment of matching electrical contacts on the base station and the mouse.

In the case of a mouse where the body of the mouse is rotationally symmetrical, it is advantageous if the means of transmitting charging power from a base station to the mouse is insensitive to the rotational orientation of the mouse with respect to the charging station.

Alternately it is advantageous if a mechanism is provided for locating the mouse on a charging station such that electrical connection can only be achieved when the mouse is located in the correct orientation on the charging station thereby ensuring the transmission of charging power in the correct manner. It is common for mice of the prior art to provide one or more dimensions of scrolling control in addition to two dimensions of pointer control. This is generally provided by means of one or more scroll wheels, or a trackball, touchpad or joystick mounted in the outer shell of the mouse.

Whilst the rotational mouse previously disclosed in US patent application 20040104892 provides a third dimension of input via rotation which can be used for scrolling functions on the host computer, there a number of possible reasons why additional scrolling input might be desirable. Firstly, the rotational input of the mouse can only be mapped to one scrolling direction at any time, whereas many software applications allow scrolling in both the 'X' and 'Y' directions. Also, the rotational input of the mouse may be assigned to special functions such as the rotation of rotary controls and therefore additional inputs may be needed for scrolling functions.

Therefore it is an advantage to provide a secondary input device such as a trackball within the rotational mouse to provide additional input for scrolling or other functions, where the operation of the secondary input device is compensated for orientation of the mouse.

In some situations the space available for use of an input device can be very limited. An example is in a music production or DJ environment where music equipment takes up a large amount of the available workspace. Therefore it is an advantage to provide an input device which allows at least three degrees of input without requiring the device to be moved on the working surface.

Typically the data reported by a mouse of prior art to a host computer is of a data type referred to as 'relative data', being for example the amount of relative

displacement in a certain direction since the last data report was sent. Another type of movement data is referred to as 'absolute data', for example the precise position of a stylus relative to the surface of a tablet device.

The types of sensor generally employed in a mouse such as optical sensors and optical-mechanical encoders provide only relative data. It is generally not practical to report absolute data since the absolute position of the mouse with respect to any particular reference point is not known.

In the case of the rotational mouse which incorporates a compassing device, the compassing device provides absolute rotational data with respect to its environment. Therefore it is practical to provide absolute data to the host computer corresponding to the rotation angle of the mouse, in addition to relative rotational data to maintain compatibility with normal mice which feature a scrolling device with a relative sensor.

Objects and Summary of the Invention It is an object of the invention to provide an improved rotational mouse which provides additional button inputs as well as a dimple feature for finger operation while rotating.

It is also an object of the invention to provide an improved rotational mouse which maintains accuracy when operated on a non-horizontal surface or a surface with a variable angle of tilt.

It is also an object of the invention to allow additional button functions on a rotational mouse by providing buttons which are sensitive to the orientation of the mouse for their function.

It is also an object of the invention to provide an internal battery charging function in a rotational mouse where the orientation of the mouse on a charging station is inconsequential.

It is also an object of the invention to provide an improved rotational mouse with additional scroll functions.

It is also an object of the invention to provide an input device with at least three degrees of freedom which can be operated in a limited space.

It is also an object of the invention to provide an improved rotational mouse which transmits absolute orientation data as well as relative rotational data to a host computer.

Accordingly there is provided an improved rotational mouse. A dual function dimple button is provided. A geomagnetic compassing device incorporating an optional tilt sensor is included. Button functions are sensitive to the orientation of the mouse as determined by the compassing device. Battery charging features are provided whereby the mouse can be located on a charging station at any angle of rotation. Alternate battery charging features are provided whereby an electrical connection between the mouse and a charging station can only be made when the mouse is located in the correct orientation with respect to the charging station. Additional scroll functions are provided by way of a secondary input device. In some embodiments, the mouse can allow at least three dimensions of input in a limited space without moving in translation. In the preferred embodiment, the mouse sends absolute orientation data to the host computer in addition to relative movement data.

Brief Description of the Drawings Figure i is a perspective view of a rotational mouse including an orientation button and a dimple button;

Figure 2 is a perspective view of the rotational mouse with the top shell removed to show internal features;

Figure 3 is an exploded perspective view of the major components of the rotational mouse;

Figure 4 is a cutaway detail view showing the dimple button and associated components;

Figure 5A is a cutaway section view of the mouse showing the outer shell and associated components;

Figure 5B is a hidden detail view showing the preferred arrangement of moulded-in stitches in the outer shell;

Figure 6A is an illustration showing charging features on the underside of the mouse and a charging station;

Figure 6B is a cutaway section view of the mouse resting on the charging station;

Figure 6C is an electrical schematic diagram showing a rectifier circuit for transmitting charging power;

Figure 7 is a cutaway section view of a mouse mounted on a charging station where inductive charging is employed;

Figure 8A is a hidden detail view showing a rocker plate arrangement for radially mounted switches;

Figure 8B is a cutaway section view showing a rocker plate arrangement for radially mounted switches;

Figure 9 is a hidden detail view showing a segmented button arrangement for the operation of radially mounted switches;

Figure 10 is a hidden detail view showing a radial arrangement of touch sensors in addition to a switch;

Figure 11 is a schematic diagram illustrating the determination of switch functions according to the position of a switch or touch sensor element and the orientation angle of the mouse;

Figure 12A is an illustration of a rotational mouse with a centrally mounted trackball;

Figure 12B is a schematic diagram showing the 5 dimensions of input provided by a rotational mouse including a trackball;

Figure 13 is an illustration showing a rotational trackball device;

Figure 14 is a schematic diagram showing the reporting packet format of a rotational mouse including relative rotation and absolute orientation data; Figure 15 is a perspective view showing a mouse 1500 and a matching base unit 1506 according to one aspect of the invention;

Figure 16 is a cross-sectional view of the mouse 1500 resting in a working orientation on the base unit 1506;

Figure 17A is a plan view showing the locating bosses 1508 1510 in correct alignment with the apertures 1502 and 1504; and

Figure 17B is a plan view showing the locating bosses 1508, 1510 in 180° misalignment with the apertures 1502,1504.

Detailed Description of the Preferred Embodiments

Provided is an improved rotational mouse with three degrees of freedom. A solid state compassing device is employed to measure rotational orientation relative to the Earth's magnetic field or whatever static magnetic field exists in the operating environment of the mouse, in addition to an X-Y sensor such as an optical sensor for measuring lateral displacement relative to an operating surface in two dimensions. Movement and orientation data is transmitted via wireless transmission to a base station which is then connected to a host computer. In some embodiments the wireless base station may be integrated into the host computer.

The mouse has some similarities to the device described in US patent application 20040104892 entitled 'Computer Mouse with Magnetic Orientation Features' however several improvements have been made to its design and functionality.

Referring to Fig 1, the rotational mouse 100 includes a top shell 101 and a base 102. The overall shape of the mouse is rotationally symmetrical around its

vertical axis to allow for operation of the mouse at any angle of orientation. The base of the mouse 102 contains a ball race and recharging features. An orientation button 103 and a concave dimple button 104 protrude through the top shell 101. The orientation button 103 has the function of setting the base orientation, or 'up' direction of the mouse. The base orientation is required to be set when the mouse is in its operating environment since the orientation of the operating environment relative to the Earth's magnetic field is unknown. The orientation button is preferably somewhat arrow shaped and acts as a physical orientation marker for the user as well as an orientation button.

Upon pressing the orientation button, the current orientation angle as determined by the compassing device is stored in memory as the base orientation. Preferably, the base orientation is stored in non-volatile memory such as flash RAM or battery-backed RAM so that the base orientation only needs to be set once for any particular operating environment.

The operation of the orientation button is described in further detail with reference to Fig 2 and Fig 3. The dimple button 104 has two distinct purposes in the use of the invention. In the first instance the dimple button provides a finger location point for continuous rotation of the mouse in a manner similar to a 'jog wheel' as is commonly found in video editing systems. In this mode the mouse is typically operated solely with the tip of the index or other finger.

In the second instance the dimple button acts as an input switch to activate functions on the host computer. Preferably, the operation of the dimple button switch provides a signal to the host computer which is compatible with the signal provided by depressing the scroll wheel on a typical scrolling mouse. This is commonly referred to as a 'third button'.

The dimple button may cause the mouse to send a scrolling signal in a different direction to the default scrolling signal direction. For example, the rotation of the mouse may by default cause a vertical scrolling action to be

performed on the host computer to which the mouse is connected. The rotation of the mouse whilst holding the dimple button may cause a horizontal scrolling action to be performed instead.

The operation of the dimple button is described in further detail with reference to Fig 2 and Fig 4. Referring to Fig 2, the rotational mouse 100 includes an inner shell 200 which is attached by means of clips 201 to a baseplate 202. The dimple button 104 is moveably retained in an opening 203 in the inner shell, with the dimple button able to move both rotationally and vertically within the opening. The orientation button 103 is integrally moulded into the inner shell 200 with an integral hinge provided at 206. One of a plurality of side button switches can be seen at 204 mounted on pins integral to the baseplate 202. A top button switch 205 protrudes through an opening in the inner shell 200. A plurality of side button locator holes 207 are featured on the inner shell 200. The operation of the side buttons is described in further detail with reference to Fig 3 and Fig 5.

Referring to Fig 3, the top shell 101 of the rotational mouse 100 includes openings 301 and 302 to allow the operation of the orientation button 103 and the dimple button 104 respectively. One of a plurality of side buttons is shown at 303. The purpose of the side buttons is to transfer user input from the perimeter of the outer shell 101 to the side button switches 204.

An upper PCB 304 holds the top button switch 205, dimple button switch 305, orientation switch 306, lateral 2-axis linear magnetic sensor 307 and an optional tilt sensor 308. A rechargeable lithium ion or similar battery 309 is mounted on the underside of the upper PCB. The lateral 2-axis linear magnetic sensor 307 forms the basis of a solid state compass which is used to determine the orientation angle of the mouse relative to the Earth's magnetic field, or whatever static magnetic field exists in the operating environment of the mouse. The optional tilt sensor 308 is preferably another linear magnetic sensor mounted perpendicularly to the

surface of the upper PCB 304. Alternatively the tilt sensor 308 may be an acceleronieter such as a MEMS accelerometer device similarly mounted.

The outputs from the linear magnetic sensor 307 and tilt sensor 308 are fed optionally via one or more amplifier circuits (not shown) to analogue inputs of a microprocessor wherein the angle of orientation is calculated.

The implementation of a solid state compassing device using two or three sensors is known in the art. Examples of such an implementations can be found in the document 'Application Note AN00022 Electronic Compass Design using KMZ51 and KMZ52' published by Philips Semiconductors Systems Laboratory Hamburg, Germany 2000.

A lower PCB 310 holds an optical sensor 311 and associated components. The side button switches 204 are electrically attached to the lower PCB 310 via angled pins in addition to being rigidly mounted on pins protruding from the baseplate 202. A lens 312 for the optical sensor is mounted between the lower PCB and the baseplate.

A plurality of recharge plates 313 are attached with tabs through the baseplate 202, and a plurality of recharge springs 314 transfer power from the recharge plates to pads on the underside of the bottom PCB 310.

The operation of the charging features of the mouse is described in further detail with reference to Figs 6A - 6C and Fig 7. A ball race 315 is interposed between the baseplate and the thrust ring 316, to which a low friction pad 317 is attached.

A retainer ring 318 attaches to the baseplate 202 by means of mechanical clips, and retains the thrust ring 316 and ball race 315 to the baseplate. The retainer ring also retains the inner shell mounting clips 201 and the rim of the outer shell 101 when it is in place.

The baseplate 202, recharge plates 313, recharge springs 314, ball race 315, thrust ring 316, low friction pad 317 and retainer ring 318 collectively comprise the base 102 of the rotational mouse as described with reference to Fig 1.

Fig 4 is a cutaway detail view showing the dimple button and associated components.

The dimple button 104 is moveably housed in an opening 203 in the inner shell 200. Suitable clearance is provided between the outer walls of the dimple button and the inner walls of the opening 203 to allow for rotational and vertical movement of the dimple button within the opening. A boss 402 is integrated into the inner shell 200 to restrict the vertical movement of the dimple button by way of the matching flange 403.

An actuator pin 401 which is integral to the dimple button 104 rests on the actuator of the dimple button switch 305 which is in turn mounted on the upper PCB 304. The end of the actuator pin 401 is domed to provide a rotational bearing function by limiting the contact surface area with the switch actuator. Optionally, a hardened ball bearing or other bearing device may be attached to the actuator pin 401 to improve bearing performance. Fig 5A is a cutaway section view of the mouse showing the outer shell and associated components. The outer shell 101 of the rotational mouse 100 comprises a flexible body 500 and a rigid top button insert 501 shown in solid colour. The purpose of the flexible body is to allow the operation of various buttons in different operational planes, including the top button and a plurality of side buttons 303, whilst providing a semi-sealed outer surface to the mouse. It is also intended that the operation of the plural side buttons is perceived as a single 'squeeze' action by the user of the mouse.

The top button insert 501 features location pins 502 which correspond to location holes in the inner shell 200. The purpose of the location pins 502 is to restrict the movement of the top button insert primarily to vertical movement, thus providing the best transfer of operational force from any area of the button to the actuator of the centrally mounted top switch 205.

The side buttons 303 similarly feature location pins 504 which correspond to the location holes 207 in the inner shell 200 as shown in Fig 2. The purpose of

the location pins 504 is to restrict the movement of the side buttons primarily to radial movement towards the centre axis of the mouse body thus providing the best transfer of operational force from any area of the side buttons to the actuators of the side button switches 204. Location hole bosses 505 which correspond to the location holes 207 in the inner shell provide additional restraint of movement of the side buttons 303.

Clips on the ends of the side button location pins 504 help to retain the side buttons within the inner shell 200 during both the assembly and the operation of the mouse. The clips also aid in transferring operating force from the distal portions of the side buttons 303 to the side button switch actuators by forcing the side button to act as a second order lever with the opposing clip acting as the fulcrum acting against in inner face of the corresponding location hole boss 505-

The flexible body 500 and the rigid top button insert 501 are generally made from different materials in a process commonly referred to as Over- moulding' or '2-shot moulding' in order to provide the required variation in rigidity. For example, the flexible body may be moulded from silicon rubber whereas the insert might be moulded from rigid plastic. It is often the case that such materials will not adhere reliably to one another. It is a requirement that the flexible body 500 and the top burton insert 501 maintain alignment with each other so that the openings for the orientation button and dimple button (refer to 301 and 302 in Fig 3) remain aligned with the inner shell 200 and other associated components so as to allow operation of the orientation button and the dimple button independently from the top button. As such the edge of the top button insert 501 is fully encased within the material of the flexible body 500 and a plurality of moulded stitches 503 are provided whereby the material of the flexible body is moulded through pre- moulded holes in the top button insert.

Referring to Fig 5B, stitch holes 503 are arranged around the edge of the top button insert 501, and also around the button openings 301 and 302 for the orientation button and the dimple button respectively. This arrangement of stitch holes helps to maintain the alignment of the top button insert 501 with respect to the flexible body 500 especially in the crucial areas in the vicinity of the button openings.

In alternate embodiments stitched over-moulded buttons may additionally or alternately be employed as the side buttons or any other buttons within the flexible shell of the mouse. Fig 6A is an illustration showing charging features on the underside of the mouse and a charging station. The mouse 100 has a plurality of recharge plates 313 mounted on the underside of the baseplate 202. The recharge plates are arranged radially around the centre of the baseplate. Preferably, there are three recharge plates arranged at intervals of 120 degrees, however any more than two would suffice.

A charging station 600 features a recess 601 which matches the shape of the lower portion of the mouse 100. A plurality of recharge pins 602, 603 are positioned such that they make contact with the recharge plates 313 when the mouse is resting on the charging station. Preferably, there are 2 recharge pins arranged radially at an interval of 180 degrees around an axis which corresponds to the central axis of the mouse when it is resting on the charging station. One recharge pin 602 carries positive electrical charge whilst the other recharge pin 603 carries negative electrical charge. A cord 605 connects the charging station to a power supply, preferably via a USB port on the host computer. When the mouse 100 is placed on the charging station 600 each of the recharge pins 602, 603 makes contact with one of the charging plates 313 regardless of the angle of rotation of the mouse relative to the charging station.

Fig 6B is a cutaway section view of the mouse resting on the charging station. The recharge pins 602, 603 are mounted on a PCB 605 and protrude

through the top shell of the charging station 600. When the mouse 100 is resting in the charging station, electrical current flows from the recharge pins to the recharge plates 313 which are mounted in the baseplate 202 of the mouse. Recharge springs 314 then connect the recharge plates to recharge pads (not shown) on the underside of the lower PCB 310 inside the mouse.

Fig 6C is an electrical schematic diagram showing a transmission mechanism comprising rectifier circuit, for transmitting charging power. The charging power may be transmitted from the recharge pins 602, 603 to the recharge plates 313 in a variety of combinations depending on the angle of rotation of the mouse relative to the charging station. Therefore a rectifier circuit must be employed to ensure that correctly polarised DC voltage is available to the battery charging circuit.

Recharge pads 606, 607 and 608 are supplied with electrical current via the recharge pins, plates and springs as described with reference to Fig 6A and Fig 6B. Each recharge pad is connected via 2 diodes to the positive and negative supply respectively of the battery charging circuit (not shown). Providing that at least one recharge pad is connected to a positive electrical charge and one is connected to a negative electrical charge, correctly polarised DC voltage will be provided to the battery charging circuit. In an alternative embodiment charging power from the charging station is transmitting to the mouse using inductive charge. Referring to Fig 7, a base station 700 contains a first inductive coil 701 which is preferably mounted between a PCB 703 and the top shell of the base station. A second inductive coil 702 is mounted in the baseplate 202 of the mouse 100. AC charge is applied to the first inductive coil 701. A rectifier and smoothing circuit is connected to the second inductive coil 702 inside the mouse, supplying DC charging current to the charging circuit (not shown). The rotational orientation of the first inductive coil relative to the second inductive coil is inconsequential.

Optionally, a ferrite mass (not shown) may be employed in conjunction with the first inductive coil 701 in order to increase inductive efficiency of the coil.

Due to the effects of residual magnetism on the compassing device within the mouse it is generally not practical to include a ferrite mass within the body of the mouse itself.

According to one embodiment of the invention, a plurality of radially mounted switches is provided, whereby the function of each switch at a particular time depends on the orientation angle of the mouse.

Fig 8A is a hidden detail view and Fig 8B is a cutaway section view showing a rocker plate arrangement for the operation of radially mounted switches. Within a flexible outer shell 800 is located a rocker plate 801. Underneath the rocker plate a plurality of switches 802 are arranged radially. A pivoting ball 803 is attached to the rocker plate and is moveably engaged in a ball housing 804. Actuator pins 805 are attached to the rocker plate and correspond with the actuators of the switches 802. A PCB 806 is mounted within the body of the mouse (not shown) and holds the switches and optionally the ball housing. Downward force applied to the flexible outer shell 800 is transmitted to the corresponding portion of the rocker plate 801 causing it to tilt on the pivoting ball 803 and thereby to apply actuation force to one or more of the switches 802. The first switch actuated in any application of force is recorded by a software program within the mouse. Fig 9 is a hidden detail view showing a segmented button arrangement for the operation of radially mounted switches. Within an outer shell 900 of a rotational mouse 100 is located a plurality of radially arranged segmented buttons 901. In one embodiment the outer shell is flexible and the segmented buttons are located within the shell, whereas in an alternate embodiment the outer shell is rigid and the buttons protrude through openings in the outer shell.

Each segmented button 901 corresponds to one of a plurality of radially mounted switches 902. The application of force to a segmented button results in the actuation of the corresponding switch.

According to another embodiment of the invention, the plurality of radially arranged buttons is a plurality of radially positioned touch sensors. The touch sensors are provided in addition to a switch with the function of the switch at a particular time depending on the operational state of the touch sensors and the current orientation angle of the mouse.

Fig 10 is a hidden detail view showing a radial arrangement of touch sensors in addition to a switch. Within an outer shell iooo is located a sensor plate 1001. The sensor plate maybe constructed from either a flexible or a rigid material. A plurality or radially arranged touch sensor elements 1002 are attached or integrated into the sensor plate. A ribbon connector 1003 carries the signals from the touch sensor elements to touch sensing circuitry (not shown) such as capacitive sensing circuitry. Alternately, other forms of touch sensing such as conductive touch sensing may be employed.

A switch 1004 is actuated when physical pressure is applied by the user of the mouse to the outer shell. At the time that the switch 1004 is actuated the state of each of the touch sensor elements is checked by the software program within the mouse. The touch sensor element with strongest activation state as a result of the proximity of a user's finger is recorded by the software program.

Fig 11 is a schematic diagram illustrating the determination of switch functions according to the position of a switch or touch sensor element and the orientation angle of the mouse. The base orientation line 1101 is indicative of the base orientation angle of the mouse. This is the angle corresponding to the compass reading at the time that the orientation button was last pressed and corresponds to the 'up' angle of rotation in relation to the user's environment. The offset angle line 1102 is indicative of the offset angle of the mouse in relation to the base orientation angle. The offset angle is determined by reading the current orientation angle using the compassing device and subtracting the base orientation angle. The reflected orientation line 1103 is determined by negating the offset angle with reference to the base orientation angle.

Each of the segments 1104 - 1109 correspond to the physical working area of one of a plurality of radially mounted switches or touch sensitive elements such as described with reference to Fig 8A, Fig 8B, Fig 9 and Fig 10. As the body of the mouse is rotated clockwise for example, the position of switches or touch sensor elements in relation to the user rotates by the same amount in the opposite direction i.e. anti-clockwise.

The segments 1108 and 1109 are radially positioned closest to the reflected orientation line 1103 in this example. A bisecting line 1110 radially bisects the segment 1108, and similarly a bisecting line nil radially bisects the segment 1109. The segment 1108, the bisecting line 1110 of which falls most directly to anti-clockwise of the reflected orientation line 1103 is mapped to a left mouse button' function. The segment 1109, the bisecting line 1111 of which falls most directly to clockwise of the reflected orientation line 1103 is mapped to a 'right mouse button' function. The operation of a radially arranged switch corresponding to either of these segments; or the operation of a switch in conjunction with the activation of a touch sensor corresponding to either of these segments will result in the respective function being performed on the host computer.

In some embodiments, the remainder of the segments are not mapped to any function however in other embodiments each of the segments may be mapped to one of a variety of functions.

The functions of the side button switches 204 as described with reference to Fig 2 and Fig 3 may also be determined in a similar manner depending on their position relative to the current orientation angle of the mouse. According to some embodiments of the invention, a trackball is provided as a secondary input device in the mouse to provide additional input dimensions for scrolling or similar tasks.

Referring to Fig 12A, a rotational mouse 1200 includes a top shell 1201 and a base 1202. The base 1202 contains a ball race and recharging features. An

orientation button 1203 and a dimple button 1204 protrude through the top shell 1201. Also mounted so as to protrude through the top shell 1201 is a trackball 1205. The trackball provides a fourth and fifth dimension of user input for the control of functions such as scrolling on the host computer. The movement of the trackball 1205 in two dimensions is detected using a sensing mechanism such as a second X-Y optical sensor (not shown) or a pair of optical-mechanical encoders mounted in the vicinity of the trackball and mechanically connected to it. The sensing of 2-dimensional movement of a trackball is well known in the art. Fig 12B is a schematic diagram showing the five dimensions of input provided by a rotational mouse including a trackball. The translation and rotation of the mouse 1200 affords three dimensions of input being dimension Xi as represented by arrow 1206, dimension Yi as represented by arrow 1207 and dimension Z as represented by arrow 1208. The operation of the trackball 1205 affords an additional two dimensions of input being dimension X ₂ as represented by arrow 1209 and dimension Y ₂ as represented by arrow 1210.

As with the input from the main X-Y sensor of the rotational mouse which must be compensated according to the angle of orientation of the mouse, the input signal from the trackball 1205 must be compensated for rotation of the body of the mouse and hence the orientation of the trackball in relation to the user.

Input dimensions Xi, Yi, X ₂ and Y ₂ as shown in Fig 12B are all compensated according to the current orientation angle of the mouse as determined by the compassing device and associated software programs. This compensation is achieved as follows: (1) the current orientation angle is measured using the compassing device (2) the offset angle is determined by subtracting the base orientation angle from the current orientation angle, where the base orientation angle was set using the orientation button 103 as described with reference to Fig 1 and (3) the X _x -Yi input from the main X-Y sensor and the

X2-Y2 input from the trackball are each converted from Cartesian to polar coordinates, the offset angle is added in each case, then each input is converted back to Cartesian coordinates.

In other embodiments the trackball may be replaced with a touch sensitive device or joystick to provide secondary X ₂ and Y ₂ input dimensions, with output from the touch sensitive device or joystick similarly compensated according to the orientation of the mouse.

In some embodiments of the invention the primary X-Y optical sensor is eliminated, providing a single X-Y input via a trackball in addition to a compassing device for determining 'Z' data and for compensating the X and Y input from the trackball. This provides three dimensions of input without the need to move the device in translation.

Referring to Fig 13, a rotational trackball 1300 includes a top shell 1301 and a base 1302. The base 1302 contains a ball race and recharging features. A trackball 1303 protrudes from the top shell. Apart from the elimination of the main X-Y sensor and associated components the construction and operation of the rotational trackball is similar to that of the rotational mouse as described herein. Buttons may be contained on, or in the top shell 1301 and the operation of the buttons may be dependent on the orientation angle if the device. In some embodiments of the invention, absolute orientation data is reported to the host computer in addition to relative movement in the rotational and other dimensions.

Fig 14 is a schematic diagram showing the reporting packet format of a rotational mouse including relative rotation and absolute orientation data. A data packet 1400 includes a series of bytes 1401 - 1408. Byte 1401 is for reporting the state of user operated buttons, with each of the bits 0-2 corresponding to one button function. Bits 3-7 of byte 1401 are unused in this example.

Bytes 1402-1403 are for reporting relative X and Y movement data respectively, as provided by the X-Y optical sensor and compensated according to

the orientation of the mouse. Byte 1404 is for reporting relative Z data which is determined by the change in orientation angle of the mouse since the last report was sent.

Byte 1405 is for reporting absolute orientation data as determined by the difference between the current compass reading and the base orientation angle. The absolute orientation in this example is expressed in a single byte as a number between 0 and 255 with 0 corresponding to an angle of 0 degrees 255 corresponding to an angle of (360 - 360 / 255) degrees.

Possible applications of the absolute rotational data include the control of the viewpoint of a virtual character, vehicle or camera or the absolute rotational control of any object such as an on-screen rotary control.

Bytes 1407-1408 are for reporting X and Y scroll data respectively, as provided by the trackball and compensated according to the orientation of the mouse. Byte 1408 is unused in this example. In some embodiments additional button functions may be associated with bits 3-7 of byte 1401. The additional byte 1408 may also be employed to provide additional precision to other input data by providing additional data bits.

Optionally, an acceleration function may be applied to the relative data reported by the mouse, including the relative rotational or Z data in addition to the relative X and Y movement data. The purpose of the acceleration function is to allow precise input control at low input speeds while allowing fast traversal at higher speeds of input. The acceleration function may use either an exponential mapping of input movement data to output movement data or a mapping table or a combination of both. Fig. 15 illustrates a mouse 1500 and a matching base unit 1506 according to another aspect of the invention. The mouse 1500 includes an internal rechargeable battery. A matching base unit 1506 includes a cable 1512 through which power is provided from a separate source, such as a wall socket,

transformer or host computer. Optionally, the cable may also provide a data connection to a host computer, such as via a USB interface.

The base unit 1506 features a concavity 1507 which receives the mouse 1500. Due to its symmetrical shape, the mouse would fit on the base unit at any orientation if not for locating features such as those described below.

The base unit 1506 features a first locating boss 1508 and a second locating boss 1510. Pins 1509, 1511 protrude from the top surface of the locating bosses 1508, 1510 respectively. The pins are fabricated from an electrically conductive material and are connected to the electrical circuitry in the base unit 1506. Preferably, the pins are spring loaded.

The underside of the mouse 1500 features a first aperture 1502 and a second aperture 1504 formed in its bottom surface 1501. Accessible through these apertures are electrical contacts 1503, 1505 that are connected to the electrical circuitry in the mouse. When the mouse 1500 is placed in the working orientation on the base unit 1506, the pins 1509, 1511 connect with the electrical contacts

!5O3, 1505, enabling an electrical circuit to be completed between the circuitry of the mouse and that of the base unit.

As shown in Fig. 16, the mouse 1500 fits within the concavity 1507 in the base unit 1506. The electrical contacts 1503, 1505 are attached to, and form part of the circuitry of a first printed circuit board (PCB) 1601 included in the mouse 1500. The pins 1509, 1511 are attached to, and form part of the circuitry of a second PCB 1603 that is included in the base unit. In the working orientation, the pins 1509, 1511 make physical contact and hence form an electrical connection with the electrical contacts 1503, 1505, enabling a connection between the two PCB circuitries.

The pins 1509, 1511 protrude from the locating bosses 1508, 1510 by a distance that is smaller than the separation between the mouse's bottom surface 1501 and the electrical contacts 1503, 1505.TMS arrangement makes impossible

to form a connection between any of the pins and any of the electrical contacts unless the locating bosses are correctly received by the apertures.

As shown in Fig. 17A, dimensions 'A' and 'B' of the second aperture 1504 are larger than dimensions 'a' and TD' respectively of the second locating boss 1510. Dimensions 'C and 'D' of the first aperture 1502 are larger than dimensions 'c' and 'd' respectively of the first locating boss 1508. This difference in dimensions forms a mechanical clearance which allows the bosses to easily slide in and out of the respective apertures.

Dimensions 'a' and TD' of the second boss 1510 are larger than dimensions 'C and 'D' respectively of the first aperture 1502, preventing the second boss 1510 from fitting through the first aperture 1502.

Fig. 17B depicts the misalignment between the locating bosses and the receiving apertures when the mouse and the base unit are rotated by 180° from the working orientation. The shaded areas represent portions of the locating bosses that cannot be received by the apertures in this orientation.

Note that the bosses 1508, 1510 and their corresponding apertures 1502, 1505 are shaped like symbols of electrical charges of plus ('+'for a positive electrical charge) and minus ('-for a negative electrical charge). The charging function of the bosses and the apertures is suggested by these shapes. The shapes ensure that successful assembly of the mouse and the base unit is only possible in the working orientation. The shapes further provide a visual indication of the proper orientation of the mouse on the base unit.