NZ573334A - A therapeutic arm exercise system using resistance to movement of a wheel supported arm trolley - Google Patents

Abstract

An arm exercise/rehabilitation system using resistance to motion is disclosed. The system uses an arm trolley (300) having one or more support wheels and which is arranged to support a user's arm (390) for movement over a surface (394) via the wheel(s). An actuator or actuators associated with one or more of the wheel(s) of the arm trolley (300) apply a level of braking to resist movement of the wheel(s). This applies resistance to the movement of the arm (390) of a patient to assist in their rehabilitation. A motion tracking system, using a camera for example, is arranged to sense and track movement of the trolley (300) over the surface (394) and generate representative position data. A computer system (395) then receives the representative position data to enable a user to interact with a program running on the computer (395). The computer (395) then controls the actuator(s), to apply a level of braking to resist movement of the wheel(s) based on the user's interaction with the program.

Description

10058597702* ;NEW ZEALAND PATENTS ACT, 1953 ;No: 573334 ;Date: 2 December 2008 ;COMPLETE SPECIFICATION ;ARM EXERCISE DEVICE AND SYSTEM ;We, INDUSTRIAL RESEARCH LIMITED, a New Zealand company, of Gracefield Research Centre, 69 Gracefield Road, Lower Hutt, New Zealand; MARCUS JAMES KING, a New Zealand citizen, of 424 Port Hills Road, Christchurch, New Zealand; AGNETHA KOREVAAR, a Netherlands citizen, of 255 Old Port Road, RD3, Balclutha, New Zealand; AMANDA PEATTIE, a New Zealand citizen, of 206 Waimari Road, Ilam, Christchurch, New Zealand; JOSHUA PHILIP WILSON, a New Zealand citizen, of 15 Aston Place, Richmond, Nelson, New Zealand; and BRADLEY SANDILANDS, a New Zealand citizen, of 2 Amokura Street, Fairy Springs, Rotorua, New Zealand, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: ;- 1 - ;FIELD OF THE INVENTION ;The invention generally relates to an arm exercise system. In particular, although not exclusively, the exercise system is suitable for rehabilitation exercise. ;5 ;BACKGROUND TO THE INVENTION ;Exercise systems can be used to help rehabilitate patients who have suffered a muscular or neurological disorder. Often, gravity eliminated arm exercises are prescribed to 10 patients who have suffered a muscular or neurological disorder relating to an upper limb, such as partial paralysis of an arm. ;Some exercise devices have been developed to assist with rehabilitation of the affected limbs by enabling a patient to carry out the prescribed gravity eliminated arm exercises. 15 One example is an overhead arm sling support mechanism. An arm sling is supported from above by a frame. The patient may insert their arm into the sling and perform repetitive movements for extended periods of time in order to exercise it, while the arm is supported against gravity. Another example of a device is an arm skate-board. An arm skate-board is a platform mounted on a set of four castor wheels allowing free 20 sliding across a table top. The patient may rest their arm on the platform and perform repetitive movements for extended periods of time in order to exercise it. Larger, more complex and expensive robotic exercise systems are also known. ;It is an object of the present invention to provide an improved arm exercise device and 25 system, or to at least provide the public with a useful choice. ;SUMMARY OF THE INVENTION ;In a first aspect, the present invention broadly consists in an arm exercise system 30 comprising: an arm trolley having one or more support wheels and which is arranged to support a user's arm for movement over a surface via the wheel(s), and an actuator or actuators associated with one or more of the wheel(s) of the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s); a motion tracking system that is arranged to sense and track movement of the trolley over the ;2 ;Received at IPONZ 26 May 2011 ;surface and generate representative position data relating to the movement of the trolley; and a computer system that is arranged to receive the representative position data to enable a user to interact with a program running on the computer system via movement of the arm trolley over the surface and which is also arranged to control the 5 actuator(s) to apply a level of braking to resist movement of the wheel(s) based on the user's interaction with the program. ;Preferably, the arm trolley comprises a substantially elongate housing that comprises a forearm support part that is arranged to receive and retain a user's forearm. ;10 ;Preferably, the forearm support part of the housing of arm trolley form a substantially U-shaped channel within which a user's a forearm is received and retained during use of the system. ;15 Preferably, the housing of the arm trolley further comprises a hand support platform that extends from an end of the forearm support part and which is arranged to support a user's hand. More preferably, the arm trolley comprises one or more support wheels located substantially directly below the hand support platform and wherein one or more of those wheels has an associated actuator that is operable to apply a level of braking to 20 resist movement of the wheel(s). ;Preferably, the arm trolley further comprises an associated fastening system that is operable to secure the user's forearm and/or hand to or within the arm trolley. ;25 Preferably, the one or more support wheel(s) are arranged to support the arm trolley for movement in any direction over the surface. ;By way of example, the wheels may comprise any one or more of the following types of wheels: caster wheels, ball casters, or onmi-wheels. ;30 ;Preferably, the arm trolley comprises a substantially elongate housing and in which there are one or more front support wheels are mounted underneath the housing at or toward the front end of the housing and one or more rear support wheels are mounted underneath the housing at or toward the rear end of the housing. ;35 ;3 ;Received at IPONZ 26 May 2011 ;In one form, the front support wheels comprises first and second omni-wheels that are arranged such that the rolling directions of each omni-wheel are perpendicular to each other. Preferably, each omni-wheel has an associated operable braking actuator such that level of braking applied to each omni-wheel is independently controllable. In one 5 form, each braking actuator is directly coupled to its respective omni-wheel for effecting a level of braking. In another form, each braking actuator is indirectly coupled to its respective omni-wheel via a gearing system. ;Preferably the actuator(s) of the arm trolley are powered brakes that are electronically 10 controllable by the computer system. ;Preferably, the powered brake(s) are electromagnetic brake(s) that are operatively coupled to a respective wheel and which are operable to apply a level of braking to resist rotation of the wheel via actuator control signals. More preferably, each 15 electromagnetic brake has an associated braking control circuit that is operable via actuator control signals to generate a driving current to drive the brake to apply a desired level of braking to the wheel, the level of braking being proportional to the level of the driving current. ;20 Preferably, the level of braking applied by the actuator(s) is controllable between zero to allow free rotation of the associated wheel and a maximum effective resistance level that substantially restricts rotation of the wheel. ;In one form, the arm trolley may further comprise one or more non-powered and 25 manually operable brake(s) associated with one or more of the wheels. ;Preferably, the computer system controls the actuator(s) onboard the arm trolley remotely over a wireless connection. ;30 Preferably, the arm trolley comprises an onboard controller that is arranged to generate actuator control signals for operating the one or more actuators to apply a desired level of braking to the wheel(s) and which generates the actuator control signals in response to desired level of braking signals received from the computer system. ;4 ;Received at IPONZ 26 May 2011 ;Preferably, the computer system comprises a resistance control system that is operable in either a manual mode in which the user can manually adjust the level of braking applied by the actuator(s) to their respective wheel(s) or an automatic mode in which the resistance control system automatically adjusts the level of braking applied by the 5 actuator(s) to their respective wheel(s) during the user's interaction with the program running on the computer based on predetermined configuration settings. ;Preferably, the resistance control system in manual mode comprises a graphical user interface on a display screen that is operable by the user via a computer system input 10 device to manually adjust the level of braking applied by the actuator(s) to one or more of the wheels. ;In one form, the resistance control system in automatic mode automatically adjusts the level of braking applied by the actuator(s) to one or more of the wheels based on the 15 speed of movement of the arm trolley as determined from the position data received from the motion tracking system. ;In another form, the resistance control system in automatic mode automatically adjusts the level of braking applied by the actuator(s) to one or more of the wheels based on the 20 position of the arm trolley on the surface as determined from the position data received from the motion tracking system. Preferably, the resistance control system is configured to adjust the level of braking based on the position of the arm trolley on the surface relative to designated resistance zones upon that surface, the resistance control system being arranged to automatically adjust the level of braking as the arm trolley 25 enters a resistance zone in accordance with braking level assigned to that zone as defined in the predetermined configuration settings. ;In yet another form, the resistance control system in automatic mode automatically adjusts the level of braking applied by the actuator(s) to one or more of the wheels 30 based on the distance of the arm trolley relative to a reference point as determined from the position data received from the motion tracking system. Preferably, the user's body is the reference point and wherein the level of braking applied is reduced as the distance between the arm trolley on the surface and the user's body increases. ;5 ;Received at IPONZ 26 May 2011 ;Preferably, the arm trolley further comprises one or more drive actuators associated with one or more of the wheel(s) and which are operable to drive the wheels to rotate at a desired speed to assist the user move the arm trolley over the surface. ;5 In another form, the motion tracking system is an absolute motion tracking system that is arranged to generate position data indicative of the actual position of the arm trolley on the surface. By way of example, the motion tracking system comprises an optical sensor that is arranged to capture continuous digital images of the surface or a portion of the surface within which the arm trolley moves and generates image data; a visible 10 target marker located on the arm trolley; and an image processing system that receives and processes the image data to sense and track the target marker within the images to generate the representative position data of the arm trolley movement. ;In another form, the motion tracking system is located onboard the arm trolley and is in 15 the form of a wireless infrared mouse mounted underneath the trolley for slid able movement over the surface and which is arranged to transmit the representative position data to the computer system. ;Preferably, the arm trolley comprises a hand grip device that the user's hand may grip 20 when moving the trolley over the surface. More preferably, the position and orientation of the hand grip device is adjustable. ;Preferably, the arm trolley comprises a hemispherical grip surface upon which the user may rest their hand when moving the trolley over the surface. ;25 ;Preferably, the arm trolley comprises one or more operable switches located in the vicinity of the user's hand and which are operable by the user to generate a switch actuation signal(s) that are sent to the computer system to enable the user to interact with the program running on the computer system. More preferably, the position of the 30 one or more switches is adjustable. ;Preferably, the program is a game that is presented on a display screen of the computer system and the computer system is arranged such that movement of the arm trolley over the surface by the user causes a corresponding movement of a game cursor on the game 35 screen so as to enable the user to interact with the game. ;6 ;Received at IPONZ 26 May 2011 ;In a second aspect, the present invention broadly consists in an arm exercise device comprising: an arm trolley having one or more support wheels and which is arranged to support a user's arm for movement over a surface via the wheel(s); an actuator or actuators associated with one or more of the support wheel(s) of the arm trolley and 5 which are operable to apply a level of braking to resist movement of the wheel(s); and a control system for generating actuator control signals and controlling the actuator(s) with the actuator control signals to apply a level of braking to resist movement of the wheel(s). ;10 Preferably the actuator(s) of the arm trolley are powered brake(s) that are electronically controllable and the control system is an onboard controller that is operable to generate the actuator control signals for controlling the actuator(s) to apply a level of braking to resist movement of the wheel(s). ;15 In one form, the arm trolley device may further comprise one or more non-powered and manually operable brake(s) associated with one or more of the wheels. ;The arm exercise device may also comprise any one or more of the other features mentioned in respect of the ami trolley of the arm exercise system of the first aspect of 20 the invention. ;Another system described comprises: an arm exercise system comprising: an arm trolley having one or more support wheels that is arranged to support a user's arm for movement over a surface via the wheel(s); an actuator or actuators associated with the 25 wheel(s) of the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s), or to drive movement of the wheel(s); a motion tracking system that is arranged to sense movement of the trolley over the surface and generate representative positional data relating to the movement of the trolley; and a control system that is arranged to receive the representative positional data to enable a user to 30 interact with a program associated with the control system via movement of the arm trolley over the surface and which is also arranged to control the actuator(s) to apply a level of braking to resist movement of the wheel(s), or to drive movement of the wheel(s) based on the user's interaction with the program. ;35 Another system described comprises: an arm exercise system comprising: an arm trolley having one or more support wheels that is arranged to support a user's arm for ;7 ;movement over a surface via the wheel(s); an actuator or actuators associated with the wheel(s) of the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s); a motion tracking system that is arranged to sense movement of the trolley over the surface and generate representative positional data relating to the 5 movement of the trolley; and a control system that is arranged to receive the representative positional data to enable a user to interact with a program associated with the control system via movement of the arm trolley over the surface and which is also arranged to control the actuator(s) to apply a level of braking to resist movement of the wheel(s) based on the user's interaction with the program. ;10 ;Another system described comprises: an arm exercise system comprising: an arm trolley having one or more support wheels that is arranged to support a user's arm for movement over a surface via the wheel(s); an actuator or actuators associated with the wheel(s) of the arm trolley and which are operable to drive movement of the wheel(s); a 15 motion tracking system that is arranged to sense movement of the trolley over the surface and generate representative positional data relating to the movement of the trolley; and a control system that is arranged to receive the representative positional data to enable a user to interact with a program associated with the control system via movement of the arm trolley over the surface and which is also arranged to control the 20 actuator(s) to drive movement of the wheel(s) based on the user's interaction with the program. ;Another device described comprises: an arm exercise device comprising: an arm trolley having one or more support wheels that is arranged to support a user's arm for 25 movement over a surface via the wheel(s); an actuator or actuators associated with the support wheel(s) of the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s), or to drive movement of the wheel(s); and a control system for generating actuator control signals and controlling the actuator(s) with the actuator control signals to apply a level of braking to resist movement of the wheel(s), 30 or to drive movement of the wheel(s). ;Another device described comprises: an arm exercise device comprising: an arm trolley having one or more support wheels that is arranged to support a user's arm for movement over a surface via the wheel(s); an actuator or actuators associated with the ;8 ;support wheel(s) of the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s); and a control system for generating actuator control signals and controlling the actuator(s) with the actuator control signals to apply a level of braking to resist movement of the wheel(s). ;5 ;Another device described comprises: an arm exercise device comprising: an arm trolley having one or more support wheels that is arranged to support a user's arm for movement over a surface via the wheel(s); an actuator or actuators associated with the support wheel(s) of the arm trolley and which are operable to drive movement of the 10 wheel(s); and a control system for generating actuator control signals and controlling the actuator(s) with the actuator control signals to drive movement of the wheel(s). ;The phrase "support wheel" as used in this specification and claims is intended to mean any type of component or device that is capable of supporting a body or housing that 15 retains a user's forearm and hand for gravity-supported movement upon a support svirface via rolling including, but not limited to, caster wheels, ball wheels, omni-wheels, or the like. ;The term "comprising" as used in this specification and claims means "consisting at 20 least in part of'. When interpreting each statement in this specification and claims that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. ;25 As used herein, "(s)" following a noun means the plural and/or singular forms of the noun. ;The invention consists in the foregoing and also envisages constructions of which the following gives examples only. ;30 ;BRIEF DESCRIPTION OF THE DRAWINGS ;Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which: ;9 ;Figure 1 is a block diagram showing the main components of an arm exercise system in accordance with an embodiment of the invention; ;Figure 2 shows a block diagram of the main electronic circuitry components of an arm 5 exercise device that forms part of the arm exercise system of Figure 1; ;Figures 3a and 3b show exploded and assembled perspective views respectively of the main mechanical components of an arm exercise device in accordance with a first preferred form of the invention; ;Figure 4 shows a block diagram of the operation and interaction between various 10 modules of an arm exercise system in accordance with another embodiment of the invention that employs the first preferred form arm exercise device of Figures 3a and 3b; ;Figures 5a and 5b show topside and underside perspective views respectively of an arm exercise device in accordance with a second preferred form of the invention, and 15 which includes a joystick-type handgrip device; ;Figure 5c shows a right-side elevation view of the second preferred form arm exercise device of Figures 5a and 5b; ;Figure 6 shows a topside perspective view of the second preferred form arm exercise device of Figures 5a-5c that includes a hemispherical hand rest component instead of 20 the joystick-type handgrip device; ;Figures 7a and 7b show topside and underside perspective views respectively of an arm exercise device in accordance with a third preferred form of the invention; ;Figures 8a and 8b show topside and underside front perspective views of an omni-wheel assembly of the third preferred form arm exercise device of Figures 7a and 7b; 25 Figures 8c and 8d show underside rear perspective and underside views of the omni-wheel assembly of Figures 8a and 8b; ;Figure 9 shows a schematic diagram of the main electronic control circuitry and associated components for the third preferred form arm exercise device of Figures 7a-8d without the trolley housing; ;30 Figure 10 shows a circuit diagram of a braking control circuit for controlling an electromagnetic brake coupled to an omni-wheel of omni-wheel assembly of Figures 8a-8d; ;Figure 11 shows a perspective view of an arm exercise system in accordance with another embodiment of the invention that employs the third preferred form arm exercise ;10 ;device of Figures 7a-8d and which shows a user's forearm and hand secured into the arm exercise device and interacting with a game displayed on an visual display screen; Figure 12 shows a flow diagram of the resistance control system for an arm exercise system in accordance with an embodiment of the invention; ;5 Figure 13 shows a flow diagram of an automatic adjustment mode of the resistance control system of Figure 12; and ;Figure 14 shows a topside perspective view of an arm exercise device in accordance with a fourth preferred form of the invention and which includes an operable hand switch. ;10 ;DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS ;Overview of arm exercise system ;15 Referring to Figure 1, the invention relates generally to an arm exercise system 10 comprising a moveable arm exercise device 14 for supporting a user's 12 forearm and hand against gravity on a support surface to enable rehabilitation exercises to be carried out via interaction with a game or application program or other software run on a computer system 18. The arm exercise device 14 may be in the form of an arm support 20 trolley that comprises one or more support wheels that enable the user 12 to move their arm over the support surface, when supported in or on the trolley. The support surface may be a planar surface, such as a table top, or can alternately be a contoured surface. Additionally, the support surface may be substantially horizontal relative to the ground or alternately inclined or declined relative to the user to a desired angle. In preferred 25 forms, the arm exercise device comprises one or more manually or electronically operable actuators that may be operated to apply a level of braking resistance to one, some or all of the wheels, and/or may be arranged to drive or rotate one, some or all of the wheels at a desired speed. The arm exercise device may be provided in powered or non-powered versions. In preferred forms, the arm exercise device comprises one or 30 more mechanically operated switches that may be positioned to require movement of wrist or individual finger digits in order to be operated so that a clinician may enable a wrist or finger digit movement to be exercised during operation of the switches. ;11 ;To enable the user 12 to interact with the computer system 18 via movement of the arm exercise device 14, a motion tracking system 16 is provided that senses and tracks the movement of the trolley and generates position data representing the position of the trolley relative to the support surface. The motion tracking system 16 may be entirely 5 separate and external to the trolley 14, entirely integrated with the trolley, or have some components onboard the trolley and other components located remote to the trolley as part of the computer system 18 or independent of the computer system. ;The interactive computer system 18 may be a customised computer system, gaming 10 console, gaming machine, hardware platform or alternatively a standard Personal Computer, whether a desktop, laptop, notebook or handheld computer such as a Portable Digital Assistant (PDA) or "smart" phone. In preferred forms, the interactive computer system 18 includes a processor 20, memory 22 and an output screen or visual display screen 24 upon which the application program or game is presented or 15 displayed, such as a CRT monitor, LCD screen or any other suitable electronic display device. A user interface 26, such as a conventional keyboard, mouse, or other user input control device may also be provided to allow the user and/or their clinician to initiate or configure the application program or game as required. ;20 Although not essential, the interactive computer system 18 may comprise an application/game engine 28 that stores and runs the application program or interactive game. By way of example, the application program may be any personal computer application program or game or alternatively a customised rehabilitation training game, including augmented and virtual reality games whether immersive or non-immersive. 25 In operation, the user 12 uses their arm to move the trolley 14 around the support surface and this movement enables them to interact with the application or gaming program presented on the visual display 24, much like moving a mouse on a mouse-pad. For example, in some forms, the movement of the trolley 14 over the support surface may cause a corresponding movement of a cursor on the visual display screen 24. In 30 other forms, such as augmented reality or virtual reality games, the user's hand or a graphical representation of the user's hand may be displayed on the screen 24 and move on screen to interact with the augmented or virtual reality environment in accordance with the trolley's movement over the support surface. By way of example, an augmented reality based system may employ a machine vision motion tracking system ;12 ;that utilises an optical sensor, such as a webcam or digital camera, for capturing moving images of the user's arm and trolley as it is moved over the support surface and the moving images are presented in real-time on the screen 24 with a game or application graphical overlay that the user can interact with in accordance with the game or 5 application programming. Additionally, but not required to be essential, is the ability to interact with the application program by operation of the wrist or digit movement switches. ;In the preferred form, the computer system 18 comprises an input/output interface 30 10 that is configured for transmitting and receiving data or information to and from one or more external devices in the exercise system. For example, the input/output interface 30 is arranged to communicate with the motion tracking system 16 or a part or component of the motion tracking system over a communication link 32. For example, motion tracking system 16 may be arranged to send position data relating to movement 15 of the trolley 14 to the input/output interface 30 of the computer system 18 for processing by the application/game engine 28. Alternatively, a part of the motion tracking system 16, such as a webcam or digital camera, may be arranged to send image data over the communications link 32 to the computer system 18, and an image processing algorithm of the motion tracking system may be implemented on the 20 computer system to generate the position data from the images for processing by the application/game engine 28. ;In preferred forms, the computer system 18 is arranged to send actuator control signals to a main controller onboard the trolley 14 over another communications link 34. By 25 way of example, the application/game engine 28 may comprise a resistance control system that is arranged to send actuator control signals to the trolley 14 to control the level of braking applied to one or more of the wheels. Additionally, the application/ game engine 28 may comprise an assistive motor control system that is operable to send actuator control signals over the communications link 34 to the trolley 14 to control 30 operation of one or more assistive motors to drive or rotate one or more of the wheels at a desired speed. The actuator control signals may be generated automatically by the application/game engine in response to user interaction with the application or game, or alternatively manually configured by the user or clinician. It will be appreciated that the ;13 ;communication links 32,34 may be hardwired via cables or may utilise wireless communications protocols or links, such as Bluetooth. ;The various components and modules of the arm exercise system 10, such as the 5 computer system 18, motion tracking system 16, and arm exercise device 14 are shown as separate and distinct components for clarity, but it will be appreciated that these components can be combined in various ways and/or their functionality can be distributed over between the modules, and that different hardware configurations and platforms can be utilised if desired. For example, the motion tracking system 16 may be 10 fully integrated with either the computer system 18 or the arm exercise device 14, depending on design requirements. ;Overview of arm exercise device functionality ;15 The main electronic circuitry components of the onboard control system of a powered version of the arm exercise device 14 will now be described by way of example with reference to Figure 2. Not all components are essential, depending on the application. The control system 36 of the arm exercise device 14 comprises a main controller 38, such as a microprocessor, microcontroller or other programmable hardware device that 20 is arranged or configurable to control and perform various interface and control functions. The arm exercise device 14 comprises power circuitry 40 for powering the electrical circuitry and components. In preferred forms, the power circuitry comprises an onboard battery supply or package that is preferably rechargeable. The arm exercise device 14 also comprises an input/output interface 42 that provides the main controller 25 38 with a communication links to external devices and systems as necessary. For example, the input/output interface 42 may be arranged to receive the actuator control signals from the computer system 18 over the communications link 34 for processing by the main controller 38. In the preferred form, the input/output interface 42 is in the form of a wireless transmission module, such as a Bluetooth module for transmitting 30 and receiving information wirelessly, but alternatively, a hardwired cable based interface medium for transmitting and receiving data and signals may be used if desired. ;In response to actuator control signals received from the computer system 18, the main controller 38 onboard the arm exercise device 14 may generate braking and/or motor ;14 ;actuator control signals for operating the braking control circuitry 44 and assistive motor control circuitry 46. For example, the main controller 38 may send braking control signals to the braking control circuitry 44 for controlling one or more electromagnetic brakes associated with one or more wheels of the arm exercise device 5 to apply a desired level or degree of braking resistance to rotation of the support wheel or wheels. Likewise, the main controller 38 may be configured to generate motor control signals that operate the assistive motor control circuitry 46 to drive one or more of electromagnetic motors coupled to one or more of the wheels to rotate them at a desired speed to assist movement of the arm exercise device 14 over the support 10 surface. ;The main controller 38 may also be configured to operate and control other auxiliary componentry and circuitry that may be provided. For example, the motion tracking system 16 may be a machine vision based tracking system that is arranged to sense and 15 track movement of the arm exercise device by processing a series of continuous images of the arm exercise device 14 over the support surface. To assist the image processing software to detect the arm exercise device 14 in the images, a powered tracking beacon or marker may be provided on the arm exercise device. In one form, the tracking marker may be in the form of an infrared LED and this LED may be powered by motion 20 tracking marker circuitry 48 as controlled by the main controller 38. Status and/or fault indication feedback circuitry 50 may also be provided on the arm exercise device 14 in the form of one or more LED indicators, and/or an LCD display or any other suitable form of onboard electronic feedback device. The main controller 38 may be arranged to operate the feedback circuitry to operate the feedback LEDs or LCD screen to indicate 25 faults in operation or other status levels, such as the level of resistance applied to the wheel(s) by the braking control circuitry 44 or the level of assistance and drive being provided by the assistive motor control circuitry 46. One or more operable switches may also be provided for operation by the user's hand and fingers and this is represented by switching circuitry 51. The one or more switches may be arranged to 30 control the onboard braking and/or assistive motor levels, or may be tactile switches that cause the main controller 38 to send switch actuation signals representing actuation of the switches to the computer system 18 to allow another form or dimension of input interaction or control over the game or application program being displayed on the screen 24. ;15 ;As mentioned, not all of the above components are necessarily essential to the arm exercise device as some componentry will be omitted for some preferred forms of the arm exercise device. ;5 ;The mechanical configuration of various preferred forms of the arm exercise device 14 for use in the arm exercise system 10 will now be described by way of example only. It will be appreciated that the various configurations and functionality associated with each form may be combined, swapped or interchanged between the forms as desired 10 according to the training requirement for the exercise system. It will also be appreciated that any of the various forms of the arm exercise device may be adapted for use as part of any one or more of the various embodiments of the arm exercise systems described. ;First preferred form of arm exercise device and associated arm exercise system ;15 ;Referring to Figures 3 a and 3 b, the first preferred form of arm exercise device 100 comprises or is in the form of a trolley 104 for supporting part of a user's upper limb. The trolley 104 is made from any suitable material such as plastic, aluminium or wood. In this preferred form, the trolley 104 is arranged to support a user's forearm and hand. 20 The main housing or body of the trolley 104 is elongate and comprises a forearm support part comprising two side walls 107 extending upwardly from a base surface or plate 109 to form a substantially U-shaped channel 106 along its length for receiving and supporting a user's forearm. Optionally, the trolley 104 may be provided with one or more Velcro straps, buckled straps, or some other fastening system that can be 25 fastened around the user's arm to secure it in the trolley. In this preferred form, the U-shaped channel 106 extends into a hand platform 108 that is arranged to support a user's entire hand and out-stretched fingers. The hand platform 108 may in some forms comprise a hand pad 110 that is securely retained in a recess of the hand platform 108 as a soft surface to provide comfort to the user. By way of example, the hand pad 110 may 30 be formed from any suitable soft or deformable material, such as foam, rubber or the like. Additionally, the U-shaped channel 106 may contain a U-shaped arm pad 112 which may be a soft surface to provide comfort to the user and which is received and retained within the U-shaped channel 106. It will be appreciated that padding may be provided for the hand and arm in any suitable manner. ;16 ;The underside of the housing of the trolley 104 comprises one or more support wheels 114 that are arranged to allow movement of the trolley 104 over a surface. Preferably, the wheels 114 are arranged to allow the trolley 104 to move in any direction over the 5 surface. For example, the wheels 114 provide the trolley 104 with two degrees-of-freedom of movement over the surface including side-to-side movement, back and forth movement, and any combination of side-to-side and back and forth movement relative to the user. In this preferred form the trolley comprises two wheels 114 in the form of caster wheels, one of the caster wheels 114 is mounted underneath the trolley 104 at or 10 towards the front end of the housing, and the other caster wheel is mounted at or toward the rear end of the housing. Each caster wheel 114 comprises a wheel 115 being mounted to a rotatable shaft having a rotation axis indicated by lines AA extending through a wheel block 117. The wheel block 117 is rotatably mounted via mounting plate 120 to underneath the base of the trolley 104. For example, the wheel block 117 15 may be mounted for 360° rotation about a shaft extending substantially perpendicular to the base of the trolley 104 as indicated by axis or lines BB. ;It will be appreciated that the wheels 114 may alternatively be omni-wheels, spherical wheels, roller balls, ball wheels or any other suitable type of wheel or roller allowing 20 movement of the trolley 104 over a surface. The wheels 114 are made from any suitable material, such as plastic or metal. However, the tyres or contact surface with the supporting platform preferably should have a high coefficient of friction with the platform surface in order for a suitable braking resistance to be achieved. If only one wheel 114 is provided at the front or rear ends of the housing, additional support may be 25 provided for the other end of the housing on the support surface with a suitable stabilising device, such as a sliding component or surface that is arranged to smoothly slide across the support surface. It will be appreciated that the type and arrangement of the one or more support wheels may be altered as desired to suit requirements. In preferred forms, one or more rotatable support wheels are preferably provided at or 30 toward the front of the housing and/or at or toward the rear of the housing, but in addition one or more wheels may be mounted in between the front and rear ends intermediate of the front and rear wheels. The types of wheels mounted underneath the housing may be identical or may be a mixture. ;17 ;Operable actuator system ;In this preferred form, the arm exercise device 100 comprises an operable actuator system that is associated with the wheels 114. The actuator system may have a braking 5 mechanism, or a driving mechanism, or both. The actuator system may comprise one or more operable actuators associated with one or more of the wheels 114. The actuators are controlled to either provide resistance to the wheels 114, or to drive the wheels 114 at any one time. Additionally, the actuators may be disengaged from the wheels so that no resistance or drive is provided to allow free rotation. In this preferred form shown, 10 manually operable friction clutch brakes 119 are coupled to the rotatable shafts of each caster wheel 114 and which may be manually screw turned to adjust the level or resistance applied by the brakes to rotation of the wheels 115 as desired. However, any suitable braking device or clamp may be used. ;15 Although not shown, alternative forms of the arm exercise device comprise an actuator system having one or more electric motors that are operable to provide drive to the wheels 114, however any suitable driving device may be used. In one preferred form, the actuator or actuators may be in the form of an electrodynamic brake motor. The electrodynamic brake motor(s) may be arranged to either resist the motion of the wheels 20 114 or drive the motion of the wheels 114. When the electrodynamic brake motor is resisting motion of the wheels 114, a generated electrical current may be dissipated through a resistor or fed back to a power source of the motor onboard the trolley 104. The actuators may be controlled to resist or drive the movement of the trolley 104, and therefore the user's arm, over the surface in response to actuator control signals 25 generated by a control system that may analyse movement, or improvement or deterioration of movement, of the user's arm, as will be explained later. ;Motion tracking system ;30 As mentioned, the arm exercise system comprises a motion tracking system that is arranged to sense and track the motion of the trolley 104 over the surface as moved by the user. The motion tracking system may be active or passive, and external or fully or partially integrated with the trolley 104. In this preferred form, the motion tracking system is a machine vision based optical system. The optical system may comprise a ;18 ;tracking marker 116 such as a tracking pattern, a tracking sticker, or a powered light or radiation source, such as an infrared LED. In this preferred form, the marker 116 is provided or mounted in a visible position on the trolley 104, such as on a front cover 118 that covers all or part of the hand platform 108 and the user's fingers. An external 5 optical sensor, such as a webcam or digital camera, may then be used to capture continuous images of the trolley moving over the support surface. Image processing of those images can be performed by the motion tracking system to sense the tracking marker 116 within the images and generate position data representing the movement of the trolley 104 over the support surface. It will be appreciated that the motion tracking 10 system may process the position data to generate other useful motion information relating to the trolley, such as the speed of movement, the direction of movement, the rotation of the trolley, the current and past positions of the trolley, and any other useful motion or movement information. The position data may be in any particular format, but in some forms may be in X-Y coordinates with reference to a reference frame or 2-15 axis coordinate system relating to the support surface. ;In this preferred form, the motion tracking system is an absolute motion tracking system in that it generates position data representing the real-time position of the trolley 104 on the support surface. Generally, a user may have limited use of their arm to move the 20 trolley 104, meaning that it may not be possible for the user to lift the trolley from the surface, move it to a more desirable position, and replace the trolley 104 on the surface. The absolute motion tracking system may determine absolute movement of the trolley 104 over the surface at all times. In other words, movement of the trolley 104 may be tracked independently of movement of its wheels 114. ;25 ;Interactive computer system ;Referring to Figure 4, an embodiment of the arm exercise system 150 that employs an arm exercise device or trolley of the first preferred form 100 will be described. By way 30 of example, the flow of data, signals and interactions of the user, and in some cases their clinician, when operating the arm exercise system 150 will be explained. The patient or user 152 uses their arm to move the arm exercise device or trolley 104 in any desired direction upon a support surface, such as a tabletop or desk in order to interact with a game being presented on a visual display screen 156 that forms part of an interactive ;19 ;computer system. The patient's 152 interaction with the trolley 104 is represented by arrow 153. The patient 152 or their clinician or physiotherapist 158 may manually adjust 161 the level of resistance applied by the operable braking mechanisms 119 associated with one or more of the support wheels 114, such as by changing the wheel 5 clutch brake setting 160. . ;In this example, the exercise device system employs a machine vision based optical motion tracking system of the type previously explained. The motion tracking system includes a powered tracking marker, such as an infrared (IR) light or IR LED that is mounted on a surface of the arm exercise device housing that is visible from above during operation. The motion tracking system also comprises an optical sensor, such as an IR filtered webcam or camera 162, that is mounted above the support surface upon which the arm exercise device 154 is moved. The webcam or camera 162 preferably has a field of view of the entire support surface or at least a portion of the surface within which the trolley 104 will be moved. The webcam 162 is arranged to capture continuous images of the support surface as represented by arrow 163. The captured images 164 are received by an image processing module 166 which is arranged to process the images and sense and track the IR LED within the images and thereby generate position data 168, such as X-Y coordinates representing the motion or movement of the trolley 104 upon the surface. ;This position data 168 is used as user interaction input for the game engine 170 that runs the game being displayed on the visual display screen 156. The game engine utilises the position data 168 to allow the user to interact with the game and complete 25 the task or training required. In some forms, the position of the arm exercise device on the support surface may correspond to a cursor or other graphic that is displayed on the visual display screen 156 and which is used to interact with the gaming environment displayed on the screen. As the game engine 170 receives the real time position data 168 it uses this to update the game screen environment 172 by sending screen data 173. 30 For example, game engine 170 is arranged to interpret the position data 168 to allow the user to interact with the game or program, for example by updating the position of the game cursor on the display screen 156 such that movement of the trolley 104 on the support surface causing a corresponding movement of the cursor on the screen 156. The game cursor may move around the display screen 156 at speeds and distances that ;20 ;10 ;15 ;20 ;are proportionate to the movement of the trolley 104 over the surface. The game cursor may be in any form depending on the game, but could for example be a pointer, crosshair, or table tennis paddle for a table tennis game. ;5 The position data 168 is also processed by the game engine 170 to record the user's training or task completion rate as they progress through the game and this gaming data 176 is recorded in a data log 178. The data log 178 may store the gaming information 176 in memory and also process that data and transmit the score information 179 to a game score update module 180 that is arranged to update the game score on the visual 10 display screen 156 in real time for the user as they interact with the game. As the game progresses, the game score or other game information or data may give the user an indication as to whether any improvement is being made or not. Users may exercise for longer when interacting with computer or video games. Users may exercise to a higher physical level when a computer or video game score is provided based on the user's 15 own historical performance. ;In use, the patient's physiotherapist or clinician 158 may use the game score information 182 displayed on the visual display screen 156 to alter the game settings in accordance with the patient's rehabilitation program as the user progresses with their 20 training. For example, the clinician 158 may manually alter calibration settings 184 as represented by arrow 185 in order to calibrate the game settings for the user's particular capability and training progression. The calibration settings 184 are transmitted as represented by 186 to the game engine 170 which reconfigures the game-play settings. Additionally, the clinician 158 may issue new instructions 188 to the patient 152 as to 25 how they should interact with the game. For example, when a user first begins to use the arm exercise system, soon after an injury, the range of motion of their arm may be relatively small. To enable use of the full display screen 156, the system may alternatively be arranged to automatically calibrate by analysing the positional data 168 to calculate the range of motion of the user's arm. The display screen 156 may be 30 calibrated so that the motion of the arm corresponds to the cursor moving across substantially the entire display screen 156. If the user's range of motion increases or decreases, the system may recalibrate the display accordingly. ;21 ;The trolley 104 acts as an input device to for interacting with game or other application program presented on the visual display 156. In preferred forms, the game may allow the user to compete against the program, such as a game of virtual table tennis. Alternatively, the game may allow the user to play alone, such as a puzzle game. ;5 Preferably, the program encourages the user to move the trolley 104 to achieve an objective, such as winning a game of virtual table tennis, or completing a puzzle. Such encouragement means that the movements of the trolley which the patient performs are task-based or goal-directed movements. That is that the computer provides a task which the patient must achieve by moving their arm. Task-based or goal-directed movements 10 are desirable in terms of neuro-rehabilitation exercises. As the user interacts with the program, such as the game, it may encourage them to exercise their arm through movement of the trolley 104. A user may be more inclined to exercise frequently, or for a longer period of time, if they are able to interact with a program in this way. A greater number of repetitions are desirable in terms of neuro-rehabilitation exercises. The user 15 may become more mentally engaged in their exercise when interacting with the program. Exercising by interacting with a program may be less tedious than traditional, repetitive movement style exercise. ;As mentioned, the computer system may be arranged to communicate with and control 20 the actuator(s) of the actuator system onboard the trolley, in powered versions of the arm exercise device that have electronically controllable braking and/or driving actuators associated with one or more of the support wheels. As mentioned, the computer system may communicate with the actuator(s) over a wireless or hardwired communications link and may send actuator control signals to control the actuator(s) to 25 apply braking or drive to the wheels of the trolley. The actuator(s) may also be controlled to be disengaged from the wheels to allow for free movement of the wheels. The actuator(s) may be controlled in accordance with the representative positional data. If the user moves the trolley at or above a particular speed, the actuator(s) may be controlled to apply a level of braking to resist the movement of the wheels. This extra 30 resistance may help with the rehabilitation of the user, for example by helping to build muscle tone. If the user moves the trolley at or below particular speed, the actuator(s) may be controlled to drive the movement of the wheels. This may help with the rehabilitation of the user, for example by training movement of the arm and extending limits of movement of the arm. The actuator(s) may be controlled to add resistance or ;22 ;■ drive to the wheels in any suitable manner. The actuators may be controlled to play the game or to assist in playing the game. The program may ascertain what movement should be made to complete a step of a game, such as moving a paddle in front of an approaching virtual table tennis ball or moving a puzzle piece from a location to another 5 location, for example. The computer system may sense whether the user has attempted to make the required movement. The computer system may sense whether the user is struggling to make the required movement. If the user is struggling to make the required movement, the actuators may be controlled to drive the wheels to assist the user with making the required movement. If computer system senses that the user is 10 able to consistently and easily make the required movements, the actuators may be controlled to resist the movement of the wheels. ;The computer system may be arranged to log or store the representative positional data 168. An associated time stamp may be logged with the data. The data may be stored in 15 a database on a hard drive, or in any other suitable manner. This data can then be analysed at a later time, for example to assess whether the user is making sufficient progress with their rehabilitation. The data or results of the analysis may be used by a clinician 158 such as a physiotherapist to assess the progress of the rehabilitation. The game score or other game information may be logged, analysed, reported to or used by a 20 physician 158 or other clinician in order to assess the progress of the rehabilitation also. The physician 158 or clinician may change the settings of the program remotely or non-remotely in order to update the rehabilitation according to the user's requirements. The physician 158 or clinician can program the computer system to control the actuators to provide more or less resistance to the wheels, or to provide more or less drive to the 25 wheels as the user's condition improves or deteriorates over time. This may allow the physician 158 or clinician to adjust or override the user's rehabilitation exercise regime. ;Second preferred form of arm exercise device ;30 With reference to Figures 5a-6, a second preferred form of arm exercise device 200 or trolley will be explained. The functionality and operation of the arm exercise device 200 is similar to that of the first preferred form of arm exercise device 100. The main housing or body of the arm exercise device 200 again comprises an elongate housing having a forearm support part or portion generally indicated by arrow 202. In this ;23 ;preferred form, the forearm support portion 202 comprises a lower support surface 204 from which two opposed angled walls 206 extend outwardly to form a substantially U-shaped channel for receiving and retaining the user's forearm. It will be appreciated that the walls 206 need not necessarily be angled outwardly with respect to the vertical, 5 and may alternatively extend substantially perpendicular to the lower support surface 204 or may be slightly angled inwardly. Extending from the lower support surface 204 at the front end 208 of the housing is a hand support platform 210. The hand support platform 210 is arranged to support the hand and fingers of a user. In the preferred form, the hand support platform 210 is provided with a number of mounting apertures 10 212 into which corresponding engagement protrusions of a handgrip device or hand support device 214 may be securely engaged to mount the device to the platform. ;As shown, the handgrip device 214 is in the form of a joystick type component that the user may grip with their palm and fingers in the usual fashion to assist in their 15 movement of the arm exercise device across the support surface. The various mounting apertures 212 provide a number of different configurations into which the handgrip device 214 may be mounted so as to allow the position and orientation of the handgrip devices to be adjusted and altered to suit the user's requirements and hand function capability. The handgrip device 214 shown extends substantially vertical and 20 perpendicular to the hand support platform 210, but it will be appreciated that the joystick may be angled relative to the vertical if desired. ;Referring to Figures 5b and 5c, the configuration of the support wheels of the arm exercise device 200 will be explained. In this preferred form, a caster wheel 216 is 25 provided at or toward the front of the housing beneath the hand support platform 210. The caster wheel 216 is of the same type as that described with respect to the support wheels 114 described in the first preferred form of exercise device 100. As shown, the base 218 of the housing is provided with a recess or cavity 220 into which the caster wheel 216 is mounted. The caster wheel 216 is operatively coupled to a manually 30 operable brake clutch mechanism 226 that may be screw-turned with the user's fingers to manually increase or decrease resistance applied to rotation of the wheel as required in the same manner as for the first preferred form exercise device 100. Referring to Figure 5c, the wheel peripheral rolling surface extends beyond the base 218 of the housing so as to contact the support surface beneath the trolley and allow for movement ;24 ;■across that surface. Mounted at or toward the rear end 209 of the housing are two left and right ball casters 222 that are arranged to support the rear end of the housing and allow it to move freely upon the support surface. ;5 Referring to Figure 6, an example of a different type of hand support device 224 is shown in place of the joystick handgrip device 214 on the hand platform 210. The hand support device 224 is in the form of a hemisphere or substantially hemispherical support surface mounted to mounting apertures provided in the hand support platform 210. It will be appreciated that other types of hand gripping or support devices may be 10 interchangeably attachable or mountable to the hand support platform 210 and these need not necessarily be joystick or hemispherical type components. It will be appreciated that the handgrip device or hand support devices may be interchanged and altered in terms of their position and orientation on the hand support platform as desired, and more than one may be provided if desired. Additionally, a handgrip device 15 or hand support device is not necessarily essential in other forms of the trolley in which the flat hand support platform 210 may be provided without any such additional gripping or supporting device, especially for the use with a patient or person whose hand is unable to form a grip at all. ;20 This preferred form of arm exercise device 300 may be adapted for use in any one of the arm exercise system embodiments described. ;It may also be desirable to add a hand grip that allows two handed operation of the trolley. Such a hand grip may be desirable for the rehabilitation of a patient who has 25 hemiparesis, a condition whereby one arm is considerably weaker than the other. If the clinician decides that the patient should use the stronger arm to assist the weaker arm then a handgrip which is an extended joystick will allow both hands to grip the device. ;Third preferred form of arm exercise device and associated arm exercise system ;30 ;A third preferred form of arm exercise device 300 and an associated arm exercise system will now be explained with reference to Figures 7a-13. Referring to Figures 7a and 7b, the elongate housing 302 is similar to that described with respect to the first and second preferred forms of the exercise device. In particular, an open channel 304 is ;25 ;provided for the forearm support part of the housing for receiving and supporting the user's forearm. The open channel 304 of the forearm support part is formed from a base surface 303 from which outwardly inclining walls 306 extend. The hand support platform 308 at the front end 310 of the housing 302 is provided with a hemispherical 5 hand support component or surface 312 upon which the user may rest their palm and fingers, but alternatively a joystick handgrip may be provided, or the platform may remain flat with no additional gripping or support devices in other forms. It will be appreciated that the hemispherical hand support 312 may be releasably mounted for interchanging with other handgrip devices or alternatively fixedly mounted to the hand 10 support platform 308 if desired. ;Referring to Figure 7b, the underside of the housing is substantially hollow and provides a cavity within which the electromechanical and electronic circuitry of the arm exercise device 300 can be mounted. As will be explained in more detail later, this 15 preferred form of arm exercise device 300 comprises electronic control circuitry that is mounted onboard a Printed Circuit Board (PCB) fitted into the housing and which is powered by an onboard power supply, such as a rechargeable battery package. The PCB may be mounted on mounting platform 314 and the rechargeable battery package may be securely received and retained within a battery compartment 316 accessible 20 from an outer side wall 318 of the housing. ;As to the support wheels for allowing the arm exercise device 300 or trolley to move across a support surface, left-side and right-side ball casters 320 are provided at or toward the rear end 311 of the housing. At or toward the front end 310 of the housing is 25 a centrally located omni-wheel assembly generally indicated by arrow 322 and which is arranged to allow for two degrees of freedom of movement in any direction over the support surface. In this preferred form, the omni-wheel assembly is preferably mounted directly below the base of the user's hand support 312 or in a central position on the hand support platform in order to maximise the weight on the wheels of the omni-wheel 30 assembly and therefore enable maximum possible resistance to be encountered by the user if resistance is applied to the wheels, for example via an operable braking system to be described. ;26 ;Referring to Figures 8a-8d, the preferred form omni-wheel assembly will be explained in further detail by way of example only. In this preferred form, the omni-wheel assembly 322 comprises first 324a and second 324b omni-wheels. In this preferred form, the pair of omni-wheels 324a,324b are perpendicularly mounted with respect to 5 their respective wheel rolling axes. It will be appreciated that each omni-wheel 324a,324b comprise a series of smaller rollers 328a,328b situated around the circumference of the wheel and which are arranged to allow unrestricted motion perpendicular to the wheel direction of rolling as will be explained with reference to Figure 8d below. ;10 ;Referring to Figure 8d, the first omni-wheel 324a is mounted to a rotatably mounted shaft or axle 326a to allow the wheel 324a to rotate clockwise or anticlockwise about an axis as represented by line YY such that it has a rolling direction either forward or backward as represented by double ended arrow D. Figure 8d shows the circumferential 15 smaller rollers 328a situated on the circumference of the wheel 324a. These series of rollers 328a are arranged to have a rolling direction that is perpendicular to the wheel rolling direction D to thereby allow unrestricted motion perpendicular to the wheels direction of rolling. As mentioned, the second omni-wheel 324b is mounted at a perpendicular orientation relative to the first omni-wheel 324a, but otherwise has the 20 same configuration. For example, the wheel 324b is mounted upon a rotatable shaft or axle 326b that extends through the mounting frame assembly and which allows the wheel 324b to rotate clockwise or anticlockwise about axis represented by line XX such that it has a rolling direction as indicated by double ended arrow C. As can be seen, the rotation axes YY,XX of the respective omni-wheels 324a,324b are substantially 25 perpendicular and in the same plane, and each omni-wheel is of the same diameter. Again, omni-wheel 324b comprises a series of circumferential rollers 328b that are arranged to roll in a direction that is perpendicular to the wheel axis XX to allow unrestricted motion of the wheel perpendicular to its rolling direction C. ;30 Reverting to Figure 8a, the omni-wheels 324a,324b and associated componentry are mounted to a mounting framing assembly comprising a bracket assembly. In this preferred form, the bracket assembly comprises a first bracket 330a and a second bracket 330b. Each of the brackets 330a,330b further comprises an omni-wheel sub-bracket 332a,332b and a braking mechanism sub-bracket 334a,334b. The omni-wheel ;27 ;sub-brackets 332a,332b are substantially U-shaped brackets having a flat base plate 336a,336b from which two parallel walls 338a,338b extend and between which the respective omni-wheels 324a,324b are mounted via their respective shafts 326a,326b extending through the parallel walls 338a,338b. Referring to Figure 8b, in this 5 preferred form, each of the shafts 326a,326b are rotatably mounted within and supported at their ends by bearings 344a,344b that are mounted to the outside surface of walls 338a,338b of the omni-wheel sub-brackets 332a,332b. The braking mechanism sub-brackets 334a,334b have a similar construction in that they are U-shaped and comprise a base plate 340a,340b from which two parallel walls 342a,342b extend and 10 between which an operable braking mechanism for each omni-wheel 324a,324b is provided. As shown, adjacent respective walls 338a,338b and 342a,342b of the sub-brackets are fixed together. The collective base plates 336a,336b and 340a,340b of the sub-brackets collectively form a mounting surface for attaching or fixing underneath the recess of the housing of the trolley, for example via fixing components like screws or 15 rivets extending through mounting apertures in the base plates and into a base plate or surface in the recess of the housing of the trolley. The two omni-wheel sub-brackets 332a,332b are coupled together by an L-shaped mounting plate 335. ;Referring to Figure 8c, the operable braking mechanism for each of the omni-wheels 20 will now be described in further detail. In this preferred form, electronically controlled and operable braking mechanisms are employed and which can be controlled with braking control signals to apply a desired degree or level of resistance to rotation of the omni-wheels 342a,324b as desired. The operation and control of the braking mechanism can be electronically controlled onboard or remotely, and automatically or 25 manually, via game or program interaction with the computer system by the user as has previously been described and which will be described in further detail later. ;In this preferred form, each of the braking mechanisms may be independently controlled such that a varying degree of resistance may be applied independently to either of the 30 omni-wheels 324a,324b. For example, a higher level of resistance may be applied to rotation of the first omni-wheel 324a which is rolling in direction D and a lesser level of resistance may be applied to the second omni-wheel 324b which is rolling in direction C, or vice versa. This differential resistance capability provides the user, their clinician or the gaming or application program with the ability to selectively vary and alter the ;28 ;level of resistance in particular directions of movement relative to the arm exercise device. For example, more resistance may be applied to movement of the arm exercise device in either one of the rolling directions C or D of the omni-wheel assembly 322 in accordance with trying to work on different muscle groups associated with the user's 5 arms and their specific rehabilitation requirements. ;It will be appreciated that various electronically controlled or operable braking mechanisms may be coupled to each of the omni-wheels 324a,324b, including electromagnetic brakes, electromotive brakes, stepper control motors, or operable 10 friction brake pads contacting the wheel. In this preferred form, two electromagnetic particle brakes 350a,350b are employed, one for each omni-wheel 324a,324b. It will be appreciated that the operable brakes 350a,3 50b may be directly or indirectly coupled or operatively connected to the rotatable shafts 326a,326b of the omni-wheels 324a,324b. In this preferred form, each of the brakes 350a,350b comprise a braking shaft 325a,325b 15 that are indirectly coupled via a gearing mechanism to the rotatable shafts 326a,326b of the omni-wheels 324a,324b. In this preferred form, the gearing mechanism associated with each brake has a gearing ratio of 2:1, but it will be appreciated that the gearing ratio may be varied to suit the torque requirements and resistance requirements for the particular wheel and braking mechanism being employed. In this preferred form, each 20 gearing mechanism comprises a first rotatable gear 354a,354b that is fixed to the braking shafts 352a,352b and a second gear 356a,356b that is fixed to the rotatable shafts 326a,326b of the omni-wheels. It will be appreciated that the gears may be spur gears having a toothed peripheral surface that are arranged to mesh together. In this preferred form, the braking shafts 352a,352b and rotatable shafts 326a,326b are parallel 25 in alignment. ;In operation, each of the brakes 350a,350b is electronically controlled with control signals to vary the resistance applied to the braking shafts 352a,352b from a level that is freely rotatable (zero resistance) to a maximum resistance level which is transferred via 30 the gearing mechanism to resist rolling of either or both the omni-wheels to the desired level. It will be appreciated that the circumferential rollers 328a,328b are independent of the braking mechanism and are unrestricted as to their rotation. ;29 ;Referring to Figures 9-12, the electronic circuitry and componentry of the third preferred form of arm exercise device 300 will be described in further detail, and in particular the resistance control system for operating the brakes 350a,350b. ;5 Referring to Figure 9, the main electronic circuitry is provided on PCB 360. By way of example, the omni-wheel assembly 322 is shown, including omni-wheels 324a,324b and their respective brakes 350a,350b. Cables 362a,362b connect the brakes to the PCB 360 and the level of resistance applied by each respective brake are controlled by braking control signals that drive and power each brake 350a,350b. As previously 10 mentioned, the arm exercise device includes power circuitry and in the preferred form this comprises a rechargeable battery 364 that delivers power to the electronic circuitry on the PCB 360 and which is mountable in the battery compartment 316 of the housing of the arm exercise device 300. As mentioned, the control and operational circuitry may comprise status/fault indictors in the form of LEDs or other output displays 366, 15 such as a small LCD screen. A system on/off switch 368 is provided for powering up and shutting down the arm exercise device when desired. As mentioned with respect to Figure 2, this powered version of the arm exercise device includes a main controller in the form of a microprocessor 370 that is arranged to communicate with external devices, such as the interactive computer system, and is arranged to control the brakes 20 350a,350b in response to onboard or externally received control signals. In this preferred from, the PCB 360 is provided with a wireless communication module, such as a Bluetooth module which acts as an input/output interface for communicating with external devices, such as the interactive computer system upon which the user interacts with a game or application program via a movement of the arm device on the support 25 surface. It will be appreciated that in an alternative form the PCB 360 may be hardwired via a cable to the interactive computer system or other external gaming system as desired. ;In this preferred form, the main controller 370 receives first and second desired braking 30 level signals indicative of the desired level of braking to be applied to each of the first and second omni-wheels 324a,324b. For example, the desired braking level signals are received from the computer system, such as the personal computer, via the onboard Bluetooth module on the PCB 360. In response to the desired braking level signals, the ;30 ;main controller 370 generates the appropriate braking control signals for the respective braking control circuitry that drives each of the brakes 3 50a,3 50b. ;Referring to Figure 10, an example of the braking control circuitry 380 for operating the 5 first brake 350a is shown. In this circuit diagram, the brake 350a is represented by a brake equivalent model comprising a series resistor Rb and inductor Lb. The braking control circuitry 380 is connected to the brake 350a via cabling 362a (shown in Figure 9). In this preferred form, the braking control circuitry 380 is arranged as a current controller for the brake 350a. In this preferred form, the brake 350a delivers a braking 10 torque that is directly proportional to the driving current Id supplied by braking control circuit 380. A regulated voltage supply Vs is provided by voltage regulator 381 that receives the battery voltage Vb as input and the average driving current Id delivered by the braking circuit is controlled by the rapid switching on and off of the switch 382, which may for example be a MOSFET or any other suitable transistor or switching 15 device. The switching of the switch 382 is controlled by an input switching signal 383. In this preferred form, the switching signal 383 is a Pulse Width Modulated (PWM) input generated by the main controller 370. The duty cycle of the PWM switching signal 383 is adjusted to vary the average driving current and therefore the overall resistance level of the brake 350a. The diode D1 maintains the current flow in the brake 20 when the switch 302 is off to reduce a jerking resistance. The frequency of switching may vary but may be approximately in the order of 1kHz to ensure continuous current can be maintained in the brake 350a so that braking torque is applied smoothly to the omni-wheel. ;25 An identical braking circuit is also provided for second brake 350b and is controlled by its own PWM switching signal as generated by the main controller 370 also. As previously mentioned, each of the braking circuits is independently controllable so that varying levels of resistance can be applied to each omni-wheel independently. For example, differential resistance may be applied between the omni-wheels or 30 alternatively an equal level of resistance may be applied as desired. ;Resistance adjustment control system ;31 ;As described above with reference to Figures 9 and 10, in this preferred form the main controller and braking circuitry on board the arm exercise device is slave circuitry that adjusts the resistance applied by the brakes to their respective omni-wheels in response to control signals indicating the desired level of resistance for each omni-wheel that are 5 sent from the host computer system that is operating the interactive game or application program. As previously mentioned, the computer system may be in the form of a Personal Computer that communicates with the arm exercise device using Bluetooth or another wireless or wired communications medium. ;10 By way of example with reference to Figure 11, a user's forearm 390 and hand 391 are shown secured to the arm exercise device or trolley 300, which includes securing straps 392 and comfort pad 393. The trolley 300 is moveable in any direction via its support wheels rolling upon the flat table surface 394. In this embodiment of the arm exercise system, the arm exercise device 300 and a visual display screen 395 of the personal 15 computer are shown. The motion tracking system and other components of the Personal Computer have been omitted for clarity of explanation. A game or other application programme is presented on the visual display screen 395 and the user may interact with that game via movement of the arm exercise device upon the table surface 395, much like a normal personal computer mouse cursor. For example, movement of the arm 20 exercise device 300 on the table surface causes a corresponding movement of the cursor 396 or other graphical representation within the gaming environment presented on the visual display screen 395. As previously explained, the motion tracking system senses and tracks movement of the arm exercise device and generates position data for input into the game engine of the interactive game, thereby causing a corresponding 25 movement of cursor 396 on the visual display screen 395 in real time. As previously mentioned, the motion tracking system may be machine vision based and comprise a webcam or digital camera or digital video camera that catches continuous images of the support surface 394 and movement of the trolley 300 upon that surface and in particular a visible tracking marker (not shown) located on the trolley 300 via image processing 30 algorithms. ;Referring to Figures 12 and 13, the interactive game or application program of the computer system generally is preferably provided with a resistance adjustment control system 400. The resistance adjustment control system may be in the form of software ;32 ;running in the game engine or parallel to the game engine and is utilised to generate the5 desired resistance levels for the brakes 350a,350b coupled to the omni-wheels 324a,324b. In this preferred form, the resistance control system 400 provides the user with a selection of two adjustment modes, namely a manual adjustment mode 404 or an 5 automatic adjustment mode 406 as shown in flow diagram of Figure 12. ;In the manual adjustment mode 404, the user or their clinician can set the level of resistance for each of the omni-wheels via a graphical user interface (GUI), such as a slider bar, presented on the visual display screen 395 is shown at 406. For example with reference to Figure 11, slider bars 397a,397b are provided for setting a low or high resistance for the respective omni-wheels 350a,350b via slider bars 398a, 398b provided in a GUI. The resistance control system can generate desired resistance level signals 408 in response to manual adjustment of the slider bars or other GUI and sends these for transmission to the arm exercise device 300 over, for example, Bluetooth 410 in the input/output interface of the Personal Computer. As previously explained, the main controller 370 onboard the arm exercise device receives the desired resistance level signals 408 and generates braking control signals for the braking control circuitry to control the level of resistance applied by each of the brakes 350a, 350b as shown in step 412. In response to the braking control signals from the main controller 370, the braking control circuits vary the average current applied to the brakes and the overall resistance applied to each omni-wheel as shown in step 416. ;Alternatively, the user at step 402 may select an automatic resistance adjustment mode 418 in which the resistance applied to each of the brakes is seamlessly and gradually 25 altered automatically by the computer system in accordance with predetermined settings. In the automatic mode 418, the user can either select to have the resistance of each of the brakes 350a,350b varied according to the speed that the arm exercise device is being moved over the support surface (viscous damping) or alternatively by selecting predetermined regions or zone where particular resistance level should be applied (zone 30 damping). For example, regions of the support surface that are further away from the user may have a lower resistance level as they are usually more difficult for the user to reach compared to closer zones or regions. Additionally it may be useful to use a combination of these two resistance control systems, or any other suitable type of resistance control system. ;10 ;15 ;20 ;33 ;In the automatic adjustment mode 418, the resistance control system is arranged to process the position data 420 generated by the motion tracking system 422 and generate desired resistance level signals 422 accordingly, depending on whether viscous damping 5 or zone damping has been selected. This automatic resistance adjustment may be configured to happen seamlessly and gradually without the user's knowledge as they interact with the game or application program. As previously discussed, the motion tracking system in the preferred form comprises an optical sensor such as a webcam that records continuous images of the arm exercise device on a support surface as shown at 10 step 422a and these images are then processed by image processing software at step 422b that is arranged to detect a tracking marker or other target on the arm exercise device and generate representative position data for the game engine for causing a corresponding movement of the on screen cursor. The position data 420 can then be received and processed by the resistance control system at step 424 for generating the 15 appropriate desired resistance level signals 424 for transmitting to the arm exercise device. The automatic adjustment of resistance based on the arm exercise device position data 420 will now be explained with reference to Figure 13, and in particular an explanation of step 426 in Figure 12. ;20 Referring to Figure 13, in the automatic mode of resistance adjustment, the user can select at step 430 either viscous damping 432 or zone damping 434. Viscous damping 432 enables the user to configure the resistance control system to automatically adjust the resistance applied to the brake or brakes of the arm exercise device according to the speed of travel of the arm exercise device as represented by the cursor on the visual 25 display screen 395. Alternatively, in the zone damping mode 434 the user can configure the resistance control system to adjust the level of resistance applied by the brakes of the arm exercise device according to the position of the arm exercise device on the support surface as represented in the gaming environment by the cursor 396 in the visual display screen 395. These modes will be explained in more detail below. ;30 ;Viscous damping mode ;As mentioned, if the viscous damping mode 432 is selected, the position of the arm exercise device or cursor 396 as represented on the screen is continuously determined ;34 ;and represented by the position data 420 as shown as step 436. At step 438 the position data 420 is continuously received from the motion tracking system. In addition, the speed adjustment configuration setting 440 are received during the speed adjustment configuration 432. In particular, the speed adjustment configuration settings are set by 5 the user or their clinician to vary the level of resistance according to changes in speed of the arm exercise device over the support surface, which is controlled directly from the position data or indirectly from the speed of movement of the corresponding cursor on the display screen. For example, the user or clinician may set one or more speed thresholds that determine the level of resistance to be applied by the brakes or 10 alternatively any proportional, linear, non-linear or other relationship between speed and resistance may be set as desired. At step 438, the current and previous positions of the device are determined using the position data 420 and a calculation of speed is derived in real-time. It will be appreciated that the sampling rate of the position data determines the frequency of the continuous speed calculations. Based on the 15 determined speed of the arm exercise device movement over the surface, and in view of the speed adjustment configuration, desired resistance level signals 424a are generated at step 442 and transmitted to the arm exercise device via Bluetooth at step 410. ;Zone damping mode ;20 ;If zone damping is selected at step 434, the user or their clinician is able to configure the desired level of resistance to be applied by the brakes in particular zones within which the arm exercise device may be moved. This may be set graphically on the screen, for example by the display screen representing the total area of possible 25 movement on the support surface, or the user and their clinician may be able to select and define one or more zones and allocate desired resistance levels for each of those zones. When the arm exercise device is detected as moving into those zones, for example when the cursor moves into the zones on the screen, the resistance adjustment control system can vary the resistance applied by the brakes of the arm exercise device 30 accordingly. The zone adjustment configuration settings 444 are used in the next calculation phase 446 or alternatively the configuration settings may simply comprise a predetermined set distances of the arm exercise device relative to the user's body, such that the resistance decreases as the arm exercise device is moved further away from the user's body and therefore is more likely to be difficult to move. It will be appreciated ;35 ;that the user or their clinician may configure any desired relationship between the trolley position or distance relative to the user or some other reference point, and the resistance to be applied to the wheels of the trolley. At the calculation phase 446, the position data 420 is received and processed to determine the trolley position. This is 5 then compared with the zone or distance setting at step 448 which then generates a desired level of resistance signal 424b for sending to the arm exercise device over Bluetooth or the like at step 410. ;In summary, the automatic mode of the resistance control system enables the user or 10 their clinician to configure the exercise system to automatically adjust the level of resistance applied by the brake or brakes according to the speed, position or distance of the arm exercise device on the support surface or its graphical representation on the screen relative to the reference frame of the screen for example or some other reference point. ;15 ;Fourth preferred form arm exercise device ;Referring to Figure 14, a fourth preferred form of the arm exercise device 500 is shown. The functionality and capability of this form of arm exercise device may be similar to 20 that of the other preferred forms of device previously described with the major differences being the aesthetic and ergonomic design. ;In this preferred form, the arm exercise device 500 is provided with front left 582 and 502 and right 504 ball casters and rear left 506 and 508 ball casters from which the body 25 510 of the device moves over a support surface. As before, an open channel 512 is provided along a portion of the elongate body for receiving and obtaining the user's forearm and a hand platform 514 is provided at the front end for supporting the user's hand. Strapping or another fastening system for securing the forearm within the recess of channel 512 is also provided and may be in the form of a flexible brace that extends 30 over and around the user's forearm and secures to either side of the elongate housing or body of the arm exercise device. ;In addition to the functionality previously described in relation to the other preferred forms of arm exercise device, the fourth preferred form of arm exercise device 500 ;36 ;includes one or more hand clickers, switches, or other operable dials, buttons or knobs that can be operated by the hand or fingers of the user so as to assist them to interact with the games. For example, the switches may function similar to that of a left or right mouse button. The switches are preferably adjustably mounted in location around the 5 hand, wrist and finger region and the switches may be incorporated into the interactive game so that the game play requires operation of the switches to assist with rehabilitation of the hand, wrist or one or more fingers. The location and position of adjustability of the switch is important as it allows the clinician to customise the position of the switch so as to require the patient to move their wrist hand and/or fingers 10 in ways to encourage exercise of the effected joints. A squeeze ball type switch may also be provided to enable the user to grasp and operate the switch via a gripping motion. The proximity of the switches to the hand or part of the fingers or hands may be adjusted depending on the patient's capability. Additionally, resistance or springs may be added to the switches to increase the difficulty of actuating the switch from an 15 exercise viewpoint. ;In this preferred form, a mounting member 518 is provided at the front nose of the housing by the platform. This member 518 is curved inward over the location of the users hand and is provided with a single hand clicker button 520 that may be operated 20 by the user's fingers with an upward motion. The button 520 is wired to the onboard electronic circuitry and the main controller is arranged to transmit the switch actuation signal directly over the Bluetooth wireless module to enable interaction with the computer system as another form of user input. In this preferred form, the one or more switches are located in various positions in a quarter-hemisphere about the end of the 25 hand. ;General alternative embodiments and features Motion tracking systems ;30 ;The exercise system embodiments previously described have employed a machine vision based optical sensor, such as a webcam, digital camera, or digital video camera, that is arranged to capture images of the trolley moving on the surface and uses image processing to identify and track the trolley via an onboard tracking marker visible in the ;37 ;images to generate representative position data. However, it will be appreciated that other external motion tracking systems could alternatively be used to track the motion of the trolley upon the surface, such as beacon based RF tracking technology. ;5 In other preferred forms, the support surface itself could track the movement of the trolley. For example, the surface may be a tablet PC device, and the trolley may comprise a magnet, stylus, or other tracking device on its underside so that the tablet PC device could track the movement of the trolley. Alternatively, a grid pattern may be provided on the support surface. In this form of motion tracking system, the trolley may 10 comprise an optical sensor on its underside that is able to detect the grid pattern and ascertain the trolley's position on the surface. ;In another form, a wired or wireless mouse, roller-ball or infrared, may be mounted into the housing of the trolley and transmit position data relating to its movement with the 15 trolley in its usual fashion. It will be appreciated that this is not an absolute position tracking solution as the mouse requires calibration for the game. ;Other onboard motion tracking systems could also be used in alternative forms of the system. Such motion tracking systems may employ inertial sensors, such as 20 accelerometers. ;The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention as defined by the accompanying claims. ;25 ;38 * Received at IPONZ 26 May 2011

Claims (63)

WHAT WE CLAIM IS:

1. An arm exercise system comprising: an arm trolley having one or more support wheels and which is arranged to 5 support a user's arm for movement over a surface via the wheel(s), and an actuator or actuators associated with one or more of the wheel(s) of the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s); a motion tracking system that is arranged to sense and track movement of the trolley over the surface and generate representative position data relating to the 10 movement of the trolley; and a computer system that is arranged to receive the representative position data to enable a user to interact with a program running on the computer system via movement of the arm trolley over the surface and which is also arranged to control the actuator(s) to apply a level of braking to resist movement of the wheel(s) based on the user's 15 interaction with the program.

2. An arm exercise system according to claim 1 wherein the arm trolley comprises a substantially elongate housing that comprises a forearm support part that is arranged to receive and retain a user's forearm. 20

3. An arm exercise system according to claim 2 wherein the forearm support part of the housing of arm trolley form a substantially U-shaped channel within which a user's a forearm is received and retained during use of the system. 25

4. An arm exercise system according to claim 2 or claim 3 wherein the housing of the arm trolley further comprises a hand support platform that extends from an end of the forearm support part and which is arranged to support a user's hand.

5. An arm exercise system according to claim 4 wherein the arm trolley comprises one 30 or more support wheels located substantially directly below the hand support platform and wherein one or more of those wheels has an associated actuator that is operable to apply a level of braking to resist movement of the wheel(s). 39 Received at IPONZ 26 May 2011

6. An arm exercise system according to any one of the preceding claims wherein the arm trolley further comprises an associated fastening system that is operable to secure the user's forearm and/or hand to or within the arm trolley. 5

7. An arm exercise system according to any one of the preceding claims wherein the one or more support wheel(s) are arranged to support the arm trolley for movement in any direction over the surface.

8. An arm exercise system according to any one of the preceding claims wherein the 10 wheels may comprise any one or more of the following types of wheels: caster wheels, ball casters, or onmi-wheels.

9. An arm exercise system according to any one of the preceding claims wherein the arm trolley comprises a substantially elongate housing and in which there are one or 15 more front support wheels are mounted underneath the housing at or toward the front end of the housing and one or more rear support wheels are mounted underneath the housing at or toward the rear end of the housing.

10. An arm exercise system according to claim 9 wherein the front support wheels 20 comprises first and second omni-wheels that are arranged such that the rolling directions of each omni-wheel are perpendicular to each other.

11. An arm exercise system according to claim 10 wherein each omni-wheel has an associated operable braking actuator such that level of braking applied to each 25 omni-wheel is independently controllable.

12. An arm exercise system according to claim 11 wherein each braking actuator is directly coupled to its respective omni-wheel for effecting a level of braking. 30

13. An arm exercise system according to claim 11 wherein each braking actuator is indirectly coupled to its respective oinni-wheel via a gearing system.

14. An arm exercise system according to any one of the preceding claims wherein the actuator(s) of the arm trolley are powered brake(s) that are electronically 35 controllable by the computer system. 40 Received at IPONZ 26 May 2011

15. An arm exercise system according to claim 14 wherein the powered brake(s) are electromagnetic brake(s) that are operatively coupled to a respective wheel and which are operable to apply a level of braking to resist rotation of the wheel via actuator control signals. 5

16. An arm exercise system according to claim 15 wherein each electromagnetic brake has an associated braking control circuit that is operable via actuator control signals to generate a driving current to drive the brake to apply a desired level of braking to the wheel, the level of braking being proportional to the level of the driving current. 10

17. An arm exercise system according to any one of the preceding claims wherein the level of braking applied by the actuator(s) is controllable between zero to allow free rotation of the associated wheel and a maximum effective resistance level that substantially restricts rotation of the wheel. 15

18. An arm exercise system according to any one of the preceding claims wherein the arm trolley further comprises one or more non-powered and manually operable brake(s) associated with one or more of the wheels. 20

19. An arm exercise system according to any one of the preceding claims wherein the computer system controls the actuator(s) onboard the arm trolley remotely over a wireless connection.

20. An arm exercise system according to any one of the preceding claims wherein the 25 arm trolley comprises an onboard controller that is arranged to generate actuator control signals for operating the one or more actuators to apply a desired level of braking to the wheel(s) and which generates the actuator control signals in response to desired level of braking signals received from the computer system. 30

21. An arm exercise system according to any one of the preceding claims wherein the computer system comprises a resistance control system that is operable in either a manual mode in which the user can manually adjust the level of braking applied by the actuator(s) to their respective wheel(s) or an automatic mode in which the resistance control system automatically adjusts the level of braking applied by the 35 actuator(s) to their respective wheel(s) during the user's interaction with the program running on the computer based on predetermined configuration settings. 41 Received at IPONZ 26 May 2011

22. An arm exercise system according to claim 21 wherein the resistance control system in manual mode comprises a graphical user interface on a display screen that is operable by the user via a computer system input device to manually adjust 5 the level of braking applied by the actuator(s) to one or more of the wheels.

23. An arm exercise system according to claim 21 wherein the resistance control system in automatic mode automatically adjusts the level of braking applied by the actuator(s) to one or more of the wheels based on the speed of movement of the 10 arm trolley as determined from the position data received from the motion tracking system.

24. An arm exercise system according to claim 21 wherein the resistance control system in automatic mode automatically adjusts the level of braking applied by the 15 actuator(s) to one or more of the wheels based on the position of the arm trolley on the surface as determined from the position data received from the motion tracking system.

25. An arm exercise system according to claim 24 wherein the resistance control 20 system is configured to adjust the level of braking based on the position of the arm trolley on the surface relative to designated resistance zones upon that surface, the resistance control system being arranged to automatically adjust the level of braking as the arm trolley enters a resistance zone in accordance with braking level assigned to that zone as defined in the predetermined configuration settings. 25

26. An arm exercise system according to claim 21 wherein the resistance control system in automatic mode automatically adjusts the level of braking applied by the actuator(s) to one or more of the wheels based on the distance of the arm trolley relative to a reference point as determined from the position data received from the 30 motion tracking system.

27. An arm exercise system according to claim 26 wherein the user's body is the reference point and wherein the level of braking applied is reduced as the distance between the arm trolley on the surface and the user's body increases. 35 42 Received at IPONZ 26 May 2011

28. An arm exercise system according to any one of the preceding claims wherein the arm trolley further comprises one or more drive actuators associated with one or more of the wheel(s) and which are operable to drive the wheels to rotate at a desired speed to assist the user move the arm trolley over the surface.

29. An arm exercise system according to any one of the preceding claims wherein the motion tracking system is an absolute motion tracking system that is arranged to generate position data indicative of the actual position of the arm trolley on the surface.

30. An arm exercise system according to claim 29 wherein the motion tracking system comprises an optical sensor that is arranged to capture continuous digital images of the surface or a portion of the surface within which the arm trolley moves and generates image data; a visible target marker located on the arm trolley; and an image processing system that receives and processes the image data to sense and track the target marker within the images to generate the representative position data of the arm trolley movement.

31. An arm exercise system according to any one of claims 1-29 wherein the motion tracking system is located onboard the arm trolley and is in the form of a wireless infrared mouse mounted underneath the trolley for slid able movement over the surface and which is arranged to transmit the representative position data to the computer system.

32. An arm exercise system according to any one of the preceding claims wherein the arm trolley comprises a hand grip device that the user's hand may grip when moving the trolley over the surface.

33. An arm exercise system according to claim 32 wherein the position and orientation of the hand grip device is adjustable.

34. An arm exercise system according to any one of the preceding claims wherein the arm trolley comprises a hemispherical grip surface upon which the user may rest their hand when moving the trolley over the surface. 43 Received at IPONZ 26 May 2011

35. An arm exercise system according to any one of the preceding claims wherein the arm trolley comprises one or more operable switches located in the vicinity of the user's hand and which are operable by the user to generate a switch actuation signal(s) that are sent to the computer system to enable the user to interact with the 5 program running on the computer system.

36. An arm exercise system according to claim 35 wherein the position of the one or more switches is adjustable. 10

37. An arm exercise system according to any one of the preceding claims wherein the program is a game that is presented on a display screen of the computer system and the computer system is arranged such that movement of the arm trolley over the surface by the user causes a corresponding movement of a game cursor on the game screen so as to enable the user to interact with the game. 15

38. An arm exercise device comprising: an arm trolley having one or more support wheels and which is arranged to support a user's arm for movement over a surface via the wheel(s); an actuator or actuators associated with one or more of the support wheel(s) of 20 the arm trolley and which are operable to apply a level of braking to resist movement of the wheel(s); and a control system for generating actuator control signals and controlling the actuator(s) with the actuator control signals to apply a level of braking to resist movement of the wheel(s). 25

39. An arm exercise device according to claim 38 wherein the actuator(s) of the arm trolley are powered brake(s) that are electronically controllable and the control system is an onboard controller that is operable to generate the actuator control signals for controlling the actuator(s) to apply a level of braking to resist movement of the wheel(s). 30

40. An arm exercise device according to claim 38 or claim 39 further comprising one or more non-powered and manually operable brake(s) associated with one or more of the wheels. 44 Received at IPONZ 26 May 2011

41. An arm exercise device according to any one of claims 38-40 wherein the arm trolley comprises a substantially elongate housing that comprises a forearm support part that is arranged to receive and retain a user's forearm. 5

42. An arm exercise device according to claim 41 wherein the forearm support part of the housing of arm trolley form a substantially U-shaped channel within which a user's a forearm is received and retained during use of the system.

43. An arm exercise device according to claim 41 or claim 42 wherein the housing 10 of the arm trolley further comprises a hand support platform that extends from an end of the forearm support part and which is arranged to support a user's hand.

44. An arm exercise device according to claim 43 wherein the arm trolley comprises one or more support wheels located substantially directly below the hand support 15 platform and wherein one or more of those wheels has an associated actuator that is operable to apply a level of braking to resist movement of the wheel(s).

45. An arm exercise device according to any one of claims 38-44 wherein the arm trolley further comprises an associated fastening system that is operable to secure the 20 user's forearm and/or hand to or within the arm trolley.

46. An arm exercise device according to any one of claims 38-45 wherein the one or more support wheel(s) are arranged to support the arm trolley for movement in any direction over the surface. 25

47. An arm exercise device according to any one of claims 38-46 wherein the wheels may comprise any one or more of the following types of wheels: caster wheels, ball casters, or onmi-wheels. 30

48. An arm exercise device according to any one of claims 38-47 wherein the arm trolley comprises a substantially elongate housing and in which there are one or more front support wheels are mounted underneath the housing at or toward the front end of the housing and one or more rear support wheels are mounted underneath the housing at or toward the rear end of the housing. 35 45 Received at IPONZ 26 May 2011

49. An arm exercise device according to claim 48 wherein the front support wheels comprises first and second omni-wheels that are arranged such that the rolling directions of each omni-wheel are perpendicular to each other. 5

50. An arm exercise device according to claim 49 wherein each omni-wheel has an associated operable braking actuator such that level of braking applied to each omni-wheel is independently controllable.

51. An arm exercise device according to claim 50 wherein each braking actuator is 10 directly coupled to its respective omni-wheel for effecting a level of braking.

52. An arm exercise device according to claim 50 wherein each braking actuator is indirectly coupled to its respective omni-wheel via a gearing system. 15

53. An arm exercise device according to any one of claims 39-52 wherein the powered brake(s) are electromagnetic brakes that are operatively coupled to a respective wheel and which are operable to apply a level of braking to resist rotation of the wheel via the actuator control signals. 20

54. , An arm exercise device according to claim 53 wherein each electromagnetic brake has an associated braking control circuit that is operable via actuator control signals to generate a driving current to drive the brake to apply a desired level of braking to the wheel, the level of braking being proportional to the level of the driving current. 25

55. An arm exercise device according to any one of claims 39-54 wherein the onboard controller is remotely operable by an external device over a wireless connection to generate the actuator control signals for controlling the actuator(s) to apply a desired level of braking to resist movement of one or more of the wheels. 30

56. An arm exercise device according to any one of claims 38-55 wherein the level of braking applied by the actuator(s) is controllable between zero to allow free rotation of the associated wheel and a maximum effective resistance level that substantially restricts rotation of the wheel. 35

57. An arm exercise device according to any one of claims 38-56 wherein the arm trolley further comprises one or more drive actuators associated with one or more 46 Received at IPONZ 26 May 2011 of the wheel(s) and which are operable to drive the wheels to rotate at a desired speed to assist the user move the arm trolley over the surface.

58. An arm exercise device according to any one of claims 38-57 wherein the arm 5 trolley comprises a hand grip device that the user's hand may grip when moving the trolley over the surface and wherein the position and orientation of the hand grip device is adjustable.

59. An arm exercise device according to any one of claims 38-58 wherein the arm 10 trolley comprises a hemispherical grip surface upon which the user may rest then- hand when moving the trolley over the surface.

60. An arm exercise device according to any one of claims 38-59 wherein the arm trolley comprises one or more operable switches located in the vicinity of the user's 15 hand and which are operable by the user to generate a switch actuation signal(s) that are received by the onboard controller and sent to an external device.

61. An arm exercise device according to claim 60 wherein the position of the one or 20 more switches is adjustable.

62. An arm exercise system according to claim 1 and substantially as herein described with reference to any embodiment described or shown in the accompanying drawings. 25

63. An arm exercise device according to claim 38 and substantially as herein described with reference to any embodiment described or shown in the accompany drawings. 30 47