WO2017203298A1

WO2017203298A1 - Self-balancing unicycle device with auxiliary support

Info

Publication number: WO2017203298A1
Application number: PCT/GB2017/051528
Authority: WO
Inventors: Timur Artemev
Original assignee: Timur Artemev
Priority date: 2016-05-26
Filing date: 2017-05-26
Publication date: 2017-11-30
Also published as: GB2550884A; GB201609355D0

Abstract

There is herein proposed the concept of a self-balancing powered unicycle device having an auxiliary support. The auxiliary support is operable in at least a deployed configuration, in which the auxiliary support restricts a leaning of the unicycle device, and a retracted configuration, in which the auxiliary support permits a leaning of the unicycle device.

Description

SELF-BALANCING UNICYCLE DEVICE WITH AUXILIARY SUPPORT

FIELD OF THE INVENTION

This invention relates to the field of self-balancing unicycle devices.

BACKGROUND OF THE INVENTION

Powered self-balancing devices are well known in the prior art. In particular, it is known for a powered self-balancing device to comprise a single wheel (i.e. a unicycle) to be positioned between a user's leg for use whilst standing.

Typically, such powered self-balancing unicycle devices have an electronic and/or mechanical system that is adapted to control the rotation of the wheel so as to control the fore-and-aft balance of the device. In such devices, such as those described by US Patent Number US 6,302,230, a sensor and an electronic arrangement are provided. Information detected by the sensor and electronic arrangement is passed to a motor, which drives the wheel in the appropriate direction and at a suitable speed so as to maintain or preserve fore-and-aft balance.

Self-balancing unicycles are often seen as having a steep learning curve, such that an inexperienced or unpractised user may have difficulty in learning how to use the device appropriately. Typically, the new or unpractised user has difficulty maintaining their own balance, and controlling the orientation and/or speed of the unicycle device simultaneously.

SUMMARY OF THE INVENTION

The invention is defined by the claims.

According to an aspect of the inventive concept, there is proposed a self- balancing powered unicycle device comprising: a wheel; a drive arrangement adapted to drive the wheel; at least one foot support for supporting a user; a balance control system adapted to maintain fore-aft balance of the unicycle device by controlling the drive arrangement; an auxiliary support controllable between at least a deployed configuration, in which the auxiliary support restricts a leaning of the unicycle device in at least one direction, and a retracted configuration, in which the auxiliary support permits a leaning of the unicycle device in the at least one direction; and a control system adapted to control the auxiliary support from the retracted configuration to the deployed configuration.

In other words, there is proposed the concept of a powered unicycle device having an auxiliary or supplementary support which is selectably enabled. Such an auxiliary support is adapted to be movable from a retracted or withdrawn configuration to a deployed or extended configuration.

When in the deployed configuration, the auxiliary support may be permitted to couple the unicycle device to a ground surface so as to prevent or restrict a tilting of the unicycle device in at least one direction (e.g., the fore, aft or a side direction). When in the retracted configuration, the auxiliary support may be adapted to not restrict a tilting of the unicycle device in the at least one direction.

In this way, the auxiliary support may, in the deployed configuration, prevent an excess or unwanted tilting in a particular direction. It may be understood that the auxiliary support thereby acts as selectable 'stabilisers' of the unicycle device.

Put another way, the control system may position or configure the auxiliary support with respect to the unicycle device so as to define a maximum allowable tilt of the unicycle device in at least one direction. Beyond the defined maximum allowable tilt, further tilting of the unicycle device (in that same direction) may be restricted or prevented by the auxiliary support.

In this way, the auxiliary support may provide selectable or controllable additional support to a user of the unicycle device. This would allow a user to control the auxiliary support between the configurations dependent, for example, on their experience level or on a difficulty of the terrain. Thus, there is proposed a concept in which the stability of the unicycle device in at least one direction may be altered, adjusted or otherwise controlled.

In particular embodiments, the movement of the auxiliary support between the retracted and the deployed configuration (and vice versa) is perpendicular to a plane in which the wheel of the unicycle device lies. Thus the auxiliary support may move in a plane perpendicular to a fore-aft direction, or a forward and rearward direction, of the unicycle device. This ensures that the position of the auxiliary support is substantially the same relative to the forward and rearward direction of the wheel (i.e. direction of travel) in both the retracted and deployed configuration. This improves a predictability of the support expected by the user, and thereby a safety of the unicycle device.

In some embodiments, the auxiliary support is positioned substantially equidistant (i.e. a same distance from) a front end of the unicycle device and a rear end of the unicycle device. The auxiliary support may thereby be positioned substantially toward the middle of the length of the unicycle device.

Optionally the control system is adapted to control the configuration of the auxiliary support based on a control parameter of the powered unicycle device.

In other words, the control system may be adapted to control the configuration of the auxiliary support based on an operating parameter of the powered unicycle device (e.g. whether a control parameter exceeds or is less than a predetermined threshold value). In this way, the control system may automatically deploy the auxiliary support to automatically provide additional support to a user. Such an embodiment may thereby increase the safety or convenience of the unicycle device (as support may be automatically provided when required) and reduce a learning difficulty of the unicycle device, as support may be provided to a user, and automatically removed when the user has become accustomed to the unicycle device (e.g. when a velocity is above a predetermined threshold, as new users are unlikely to attempt to travel quickly).

Preferably the control parameter is at least one of: a speed of the unicycle device, a torque applied by the drive arrangement; an acceleration of the unicycle device; a fore-aft balance of the unicycle device; a direction of movement of the unicycle device a change in direction of movement of the unicycle device; an indication that the unicycle device has been powered on; an emergency or warning signal; a weight of the user; a signal from a gyrometer; a signal from an accelerometer; and a time since power on of the unicycle device.

In a particular embodiment, the control system is adapted to ensure the auxiliary support is in the deployed configuration when the speed of the unicycle device is below a predetermined threshold. In some embodiments, this predetermined threshold is less than 5mph, for example, less than 4mph, for example, less than 3mph.

Such an embodiment allows a unicycle device to automatically deploy auxiliary support for a user at a low speed. It has been herein recognised that, at low speeds, a user finds it more difficult to balance, especially when inexperienced or unpractised. Provision of auxiliary support only at low speeds allows for a greater deal of balance and comfort for a user, whilst ensuring that manoeuvrability of the device (e.g. at high speeds) is not significantly affected.

It will be apparent that the unicycle device may further comprise a control parameter determination unit adapted to determine a control parameter (e.g. a speed).

In some embodiments, the auxiliary support comprises at least one wheel positionable with respect to the unicycle device.

Provision of a wheel on the auxiliary support allows the auxiliary support to roll along with the powered unicycle device. This permits a greater deal of manoeuvrability and reduces possible drag caused by the auxiliary supports.

In other embodiments, the auxiliary support may instead comprise, for example, a skid pad adapted to contact a ground surface without rolling.

In yet other embodiments, the auxiliary support may provide a wheel or contact member (e.g. a skid pad) which is not positionable with respect to the unicycle device. By way of example, the auxiliary support may comprise a wheel connected to the unicycle device by a suspension arrangement having a controllable suspension. When in the deployed configuration, the suspension may be hard so as to restrict a leaning of the device, when in the retracted configuration, the suspension may be soft so as to permit a leaning of the device.

In at least one embodiment the control system is adapted to control the proximity of the at least one wheel to a ground surface, wherein the at least one wheel is more proximate to the ground surface when in the deployed configuration than when in the retracted configuration. In other embodiments, the control system is adapted to control the proximity of the at least one wheel to the unicycle device, wherein the at least one wheel is less proximate to the unicycle device when in the deployed configuration than when in the retracted configuration. Optionally, the self-balancing further comprises a user input unit, the user input unit being adapted to receive a user input and, based on the received user input, control the configuration of the auxiliary support.

Conceivably, the auxiliary support further comprises a third wheel and a fourth wheel, the third wheel being positioned on the same side as the first wheel, and the fourth wheel being positioned on the same side as the second wheel.

Preferably, the auxiliary support is coupled to the at least one foot support.

In at least one embodiment, the auxiliary support is arranged, in the deployed configuration, to restrict a side-to-side leaning of the powered unicycle device.

The auxiliary support may comprise a suspension system adapted to dampen a side-to-side leaning of the powered unicycle device.

The auxiliary support may be arranged, in the deployed configuration, to restrict a fore-and-aft leaning of the powered unicycle device.

The control system may be adapted to control the auxiliary support from the retracted configuration to the deployed configuration in response to the powered unicycle device being powered on.

The auxiliary support may comprise at least one motorized wheel.

The balance control system may be adapted to maintain fore-aft balance of the unicycle device by further controlling at least one motorized wheel of the auxiliary support.

Preferably, the width of the wheel of the unicycle device is greater than 5cm. In other words, there may be provided a wheel which is wider than a typical or standard wheel of a unicycle device. A wide wheel is herein recognised to reduce the likelihood of a unicycle device leaning from side-to-side, increasing the stability and improving the ease for a new or inexperienced user.

The self-balancing powered unicycle may further comprise a lead. Such a lead may, for example, allow a user to pull the powered unicycle device behind them if they do not wish to ride or carry the powered unicycle device.

The lead may comprise a control unit adapted to allow a user to control or override a control parameter of the unicycle device. Thus a user may control a control parameter (e.g. velocity) so as to affect the speed or driving of the wheel. This may allow a user to cause the device to 'follow' them, or travel alongside the user without requiring the user to ride the device.

The drive arrangement may comprise a hub motor, and further comprising batteries positioned between the hub motor and the perimeter of the wheel. Positioning of batteries between the hub motor and the perimeter of the wheel may provide additional space for the batteries, as well as providing an improved weight distribution of the powered unicycle device, increasing its stability.

Preferably, the batteries lie wholly within the envelope of the wheel. That is to say, in preferable embodiments, the batteries are not mounted on the outside of the wheel, but rather are wholly encompassed by the wheel.

Preferably, a mean position of the contact patches of the wheel and the auxiliary support is at a centre of the unicycle device. In some embodiments, a mean position of the contact patches of the wheel and the auxiliary support lies in a same plane as an axis about which the wheel rotates.

Here, the term contact patch refers to a portion of the wheel or auxiliary support which comes into contact with a ground surface when in the deployed configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of the invention will now be described in detail with reference to the accompanying drawings, in which:

FIG. 1 is an isometric view of an example of a powered unicycle device in a closed configuration;

FIG. 2 is an exploded diagram of components internal to the casing of FIG. 1, FIGS. 3 A & 3B are side and front elevations, respectively, of the example of

FIG. 1, wherein the casing is moving between a closed and open configuration;

FIGS. 4A & 4B are side and front elevations, respectively, of the example of FIG. 1, wherein the casing is in an open configuration and the foot platforms are in a stowed configuration;

FIG. 5 shows an isometric view of the example of FIG.1, wherein the casing is in an open configuration; FIGS 6A-6C illustrate a powered unicycle device having auxiliary supports in a retracted and deployed configuration according to an embodiment;

FIGS 7A-7B illustrate a powered unicycle device having auxiliary supports in a retracted and deployed configuration according to another embodiment;

FIGS 8A - 8B illustrate a powered unicycle device having auxiliary supports in a retracted and deployed configuration according to yet another embodiment;

FIG 9 illustrates a powered unicycle device having auxiliary supports in a retracted and deployed configuration according to a preferred embodiment;

FIG 1 OA- IOC illustrate a powered unicycle device having auxiliary supports in a retracted and deployed configuration according to another embodiment;

FIG 11 illustrates a powered unicycle device having two auxiliary supports;

FIG 12 illustrates a powered unicycle device having four auxiliary supports;

FIG 13 illustrates an auxiliary support according to another embodiment;

FIG 14 illustrates an auxiliary support according to another embodiment; and FIG 15 illustrates a powered unicycle device having auxiliary supports according to yet another embodiment.

DETAILED DESCRIPTION OF THE EMB ODEVIENT S

The term vertical, as used herein, means substantially orthogonal to the generally horizontal ground surface upon which a transportation device may be ridden. The term lateral, as used herein, means substantially parallel to the generally horizontal ground surface. Also, terms describing positioning or location (such as above, below, top, bottom, etc.) are to be construed in conjunction with the orientation of the structures illustrated in the diagrams.

The diagrams are purely schematic and it should therefore be understood that the dimensions of features are not drawn to scale. Accordingly, the illustrated thickness of any of the components or features should not be taken as limiting. For example, a first component drawn as being thicker than a second component may, in practice, be thinner than the second component.

For the purposes of a full and complete explanation, the operation of a typical powered uni cycle device will be hereafter described with reference to FIGS. 1-5, which show one embodiment of a powered transportation device 100. FIG. 1 shows the powered transportation device 100 with a casing 110 in a closed configuration so that it encases a single wheel 120. Here, the casing 110 is formed from a first, upper portion 110A that covers the top (uppermost) half of the wheel 120, and a second, lower portion HOB that covers the bottom (lowermost) half of the wheel 120. FIG 2 illustrates an exploded view of components internal to the casing 110, namely a wheel 120 and drive arrangement 135.

Referring back to FIG. 1, the wheel 120 spins about a central axis 125. The first, upper portion 11 OA of the casing is retained in a fixed position relative to the central axis 125, whereas the second, lower portion HOB of the casing is adapted to rotate about the central axis 125. Rotation of the second lower portion 1 10B about the central axis 125 moves the casing between closed and open configurations (as illustrated by FIGS. 3-4). In the closed configuration (shown in FIG. l), the casing 1 10 encloses the wheel 120 so that the outer rim 130 of the wheel 120 is not exposed. In the open configuration (shown in FIG. 5), the outer rim 130 of the wheel 120 is exposed so that it can contact a ground surface.

Referring now to FIG. 2, rotation of the single wheel 120 is driven by a drive arrangement 135 according to an embodiment. The drive arrangement 135 includes guide wheels 140 attached to an outwardly facing side of respective batteries 145. In this embodiment, there are two pairs of angled guide wheels 140, wherein the two guide wheels in each pair share are tapered or conical such that they have a sloped surface which is not perpendicular to the radial plane of the single wheel 120. Put another way, the contact surface of each guide wheel is inclined with respect to the radial plane of the single wheel 120. The guide wheels 140 of each pair are also positioned spaced apart to provide a gap between the two guide wheels of a pair.

A rib 150 is provided around the inner rim of the wheel 120 and fits into the gap between the two guide wheels 140 in each pair. The guide wheels 140 are therefore adapted to contact with the inner rim of wheel 120 where they spin along with wheel 120 and hold wheel 120 in place by way of the rib 150. Of course, it will be appreciated that other arrangements, including those with only one guide wheel per battery 145, are possible.

The batteries 145 are mounted on a motor 155 which drives a pair of drive wheels 160 positioned at the lowermost point along the inner rim of the wheel 120. The batteries 145 supply power to motor 155 and, this embodiment, there are two batteries in order to create a balanced distribution of volume and weight. However, it is not necessary to employ two batteries 145. Also, alternative energy storage arrangements may be used, such as a flywheel, capacitors, and other known power storage devices, for example.

In other conceivable embodiments, the drive arrangement 135 may comprise a stator and a rotor (which is coupled to the wheel). In this way, the drive arrangement may act as an outrunner motor, wherein an outer shell of the drive arrangement directly drives a wheel (or tyre of the wheel) about the stator. In such embodiments, the unicycle device may comprise a bearing system adapted to couple the wheel to the unicycle, thereby allowing the wheel to rotate about the stator of the drive arrangement.

The drive arrangement 135 is adapted to be fitted inside the wheel. In other words, the drive arrangement is sized and shaped so that it can be positioned in the void define by the inner rim of the wheel 120. Further, the drive arrangement 135 is movable between a locked configuration and an unlocked configuration.

In the locked configuration, when fitted inside the wheel 120, the drive arrangement 135 engages with the rim of the wheel 120 to prevent its removal from the wheel. Here, in the embodiment shown, the guide wheels 140 contact the inner rim of wheel 120 and hold wheel 120 in place by way of the rib 150 when the drive arrangement is in the locked configuration.

In the unlocked configuration, when fitted inside the wheel 120, the drive arrangement 135 disengages with the rim of the wheel 120 to permit its removal from the wheel. Here, in the embodiment shown, the drive arrangement contracts in size when moved from the locked configuration to the unlocked configuration so that the guide wheels 140 no longer contact the inner rim of wheel 120 and no longer hold the wheel 120 in place by way of the rib 150. Such reduced size (e.g. diameter) of the drive arrangement 135 when in the unlocked configuration thus enables the drive arrangement 135 to be removed from the wheel 120.

It will therefore be understood that the drive arrangement 135 of the illustrated embodiment can be quickly and easily connected or removed to/from the wheel 120 for repair or replacement, for example. Arranging the drive arrangement 135 in the unlocked configuration permits its removal or fitting from/to the wheel 120 (because, for example, its dimensions when in the unlocked configuration permit its fitting inside the wheel). When fitted inside the wheel 120, the drive arrangement can be arranged in the locked configuration so that it engages with the rim of the wheel 120 to prevent its removal (because, for example, its dimensions when in the locked configuration prevent the drive arrangement from being removed from the wheel).

When the drive arrangement 135 is fitted inside the wheel and in the locked configuration, a pair of drive wheels (not visible in FIG 2) is adapted to contact the inner rim of the wheel 120. Here, the pair of drive wheels comprises first and second rollers that are inclined with respect to the radial plane of the wheel. By way of contact with the inner rim of the wheel 120, the drive wheels transmit torque from the motor 155 to the wheel 120. It will be understood that this drive system operates by friction and it may be preferable to avoid slippage between the drive wheels and the inner rim of wheel 120. Positioning the drive wheels at the lowermost point enables the weight of a user to provide a force which presses the drive wheels against the inner rim of the wheel 120, thereby helping to reduce or avoid slippage.

Referring to FIGS. 4-5, two foot platforms 165 or foot supports are coupled to the second, lower portion HOB of the casing 110, with one on each side of wheel 120. In the open configuration, the foot platforms 165 are movable between a stowed configuration, wherein the foot platforms are substantially parallel with the plane of the wheel (as shown in FIG. 4), and an active configuration, wherein the foot platforms are substantially perpendicular to the plane of the wheel (as shown in FIGS. 5) so as to support a user's weight. Thus, in this embodiment, the foot platforms 165 are movable between: (i) a stowed configuration wherein they are flat against the side of the wheel and can be rotated (with the second, lower portion HOB of the casing) about the central axis 125 so as to be positioned inside (and covered by) the first, upper portion 11 OA of the casing; and (ii) an active configuration, wherein. Accordingly, the foot platforms 165 are upwardly foldable into a stowed configuration that narrows the profile of the unicycle 100 to aid in storage and carrying. In use, the foot platforms are moved to the active configuration, and the user stands with one foot on each platform 165.

Of course, it will be readily understood that the foot platforms 165 may alternatively be coupled to any aspect of the unicycle device 100, for example, an upper portion 110A of the casing 110. It will also be appreciated that a casing 110 need not comprise two portions, but may instead comprise, for example, a single portion which is not adapted to rotate. In such embodiments, the foot platforms 165 may be mounted on the single portion of the casing 110.

The drive arrangement 135 includes a gyroscope or accelerometer system 170 which senses forward and backward tilt of the device in relation to the ground surface and regulates the motor 155 accordingly to keep the device upright. In this way, the user is provided a way of controlling the acceleration and deceleration of the unicycle by varying the pressure applied to various areas of the foot platforms 165. It also enables the unicycle to self-regulate its balance in the fore-and-aft plane. In other words, the unicycle may regulate or maintain pitch of the unicycle relative to a ground surface.

In order to control a rotation of the unicycle device 100, that is to perform a turning manoeuvre, the user may lean or tilt the unicycle device sideways (i.e. from side-to-side). The gyroscopic effect of the lean or tilt will cause the device to begin performing a turn (e.g. undergo a banked turn). This well-known phenomenon may also called precession. In this way, the user is given a degree of control over the direction of travel by shifting his weight on the foot platforms 165 so as to cause the device to lean and thereby change direction. In other words, the user may steer the unicycle device by changing an amount of leaning (by shifting a body weight of the user).

The unicycle device may thereby be thought to lean in at least a fore-and-aft direction (thereby controlling an acceleration/deceleration) and in a side-to-side direction (thereby controlling a turn). When not in use, the foot platforms 165 are moved to the stowed configuration and then rotated (with the second, lower portion HOB of the casing) about the central axis 125 so as to move the casing to the closed configuration. Thus, in the closed configuration, the foot platforms 165 are stored inside the casing (covered by the first, upper portion 11 OA of the casing).

It may be understood that the casing may be formed from a frame and a protecting coating mounted on the frame. The frame may mount components, such as the drive arrangement and the foot platforms, thereon.

The embodiment of FIGS. 1-5 also comprises a lifting handle 180 coupled to the drive arrangement 135 via a plurality of rods 185. The lifting handle 180 is positioned at the top of the casing 110, above the wheel 120, and may be used to hold the uni cycle 100 above the ground, for example to enable a user to lift, carry, convey or place the uni cycle 100.

A retractable carrying strap 190 is also provided and attached to the top of the casing 100. The carrying strap 190 may be used to carry the uni cycle 100, for example over the shoulder of user. A hook may be provided on the bottom of the case to create rucksack-like belts from the carrying strap 190. The carrying strap 190 may also be used to pull the uni cycle 100, for example when the auxiliary supports (detailed below) are in contact with the ground/supporting surface).

The casing 110 may allow for the user to jump with the uni cycle device by, for example, squeezing the casing between the user's legs. This allows a user to overcome obstacles such as kerbs.

FIGS 6A-6C provides representative diagrams of an embodiment of a uni cycle device 200 comprising a first auxiliary support 250, 255. It will apparent that the unicycle device may generally operate in a same manner as previously described, that is to say comprising a casing 210 (formed from a single portion), a wheel 220 and a foot platform 265, also known as a foot support.

The auxiliary support of the unicycle device 200 comprises a first auxiliary support 250 and a second auxiliary support 255. As the first auxiliary support 250 and the second auxiliary support 255 operate in substantially the same manner, only the first auxiliary support 250 shall be hereafter described. It may be understood that each of the first auxiliary support and the second auxiliary support may otherwise be considered as an auxiliary support element or auxiliary support component of the auxiliary support.

The first auxiliary support comprises a pivotable wing 251 and a wheel 252 coupled to the pivotable wing.

The unicycle 200 device comprises a control system 260 adapted to control the first auxiliary support so as to control the configuration of the auxiliary support.

In the present embodiment, the first auxiliary support is coupled to the foot platform 265. It will be apparent that the embodiments are not limited thereto, and the first auxiliary support may, for example, be coupled to the casing 210 or any other aspect of the unicycle device 200.

FIG. 6A shows the first auxiliary support 250 in the retracted or withdrawn configuration, in which the (wheel of the) first auxiliary support is positioned proximate to the unicycle device 200.

FIG. 6B shows the first auxiliary support 250 in the deployed or extended configuration, in which the first auxiliary support 250 extends (outwardly) from the unicycle device, and in particular, from the foot platform 265 of the unicycle device 200. Thus the wheel of the first auxiliary support 250 is positioned less proximate to the unicycle device.

In other words, a configuration of the auxiliary support may be associated with a respective position or arrangement of the auxiliary support. In particular embodiments, a configuration of the auxiliary support is associated with respective position of a wheel of an auxiliary support to the unicycle device. The control system is adapted to adjust the position or arrangement of the auxiliary support to thereby control the configuration of the auxiliary support.

Put yet another way, each configuration of the auxiliary support may correspond to an amount to which leaning in at least one direction is restricted. By way of example, an auxiliary support in the deployed configuration may restrict a leaning in at least one direction more than an auxiliary support in a retracted configuration.

The first and the second auxiliary support may be controlled independently of one another. That is to say, elements of the auxiliary support may be controlled independently. In preferably embodiments, however, the first and the second auxiliary support are controlled together in the same manner.

With further reference to FIG 6B, the first auxiliary support 250 comprises a pivotable wing 251 adapted to be pivoted relative to the foot platform 265 of the unicycle device 200. The first auxiliary support also comprises a wheel 252 connected to the pivoting wing. It will be apparent that a proximity of the wheel 252 to the unicycle device is controlled by a pivoting of the pivotable wing. The pivoting of the pivotable wing 251 permits the first auxiliary support to move or be controlled between the retracted configuration and the deployed configuration

The control system 260 is adapted to control a rotation of the pivotable wing with respect to the foot platform 265, so as to enable control over the configuration of the first auxiliary support. That is to say, the pivotable wing 251 may be angled with respect to the foot platform 265.

The control system 220 may comprise a motorized actuator 222 adapted to move the position of the first auxiliary support. In this way, the control system can control or select a configuration of the auxiliary support of the unicycle device. It will be apparent that the auxiliary support may be associated with any number of configurations.

By way of example, the motorized actuator could be adapted to contract and expand a wire 224 connected between the first auxiliary support and the foot platform, so as to adjust the proximity of an end of the first auxiliary support to the foot platform.

In other embodiments, the pivotable wing 251 may be coupled to the foot platform 265 via a gearing mechanism (not shown) of a conceivable control system. In such embodiments, the gearing mechanism allows and defines a rotation of the pivotable wing (and thereby the auxiliary support) about the foot platform, such that the control system controls a rotation of the auxiliary support.

When in the deployed configuration (FIG 6B), the auxiliary support is adapted to readily couple the unicycle device to a ground surface when the unicycle device is tilted or leaned in a particular direction (si), as exemplified in FIG 6C. The auxiliary thereby provides a level of support to a user of the unicycle device, preventing or restricting an unintentional or undesired leaning of the device in the particular direction.

It is readily apparent that the angle of the pivotable arm 251 with respect to the foot platform defines the maximum allowable lean of the unicycle device. In this way, the control system 260 may (by controlling the angle of the pivotable arm) define the maximum allowable lean of the unicycle device in a particular direction si.

The angle of the pivotable wing (with respect to the foot platform) in the deployed position may, for example, be greater than 10°. In preferable embodiments, this angle is no less than 60°, for example, between 60° and 120°.

Preferably the wheel 252 of the auxiliary support 250 is angled such that, when the wheel comes into contact with the ground surface, the wheel is substantially vertical with respect to a ground surface.

Thus, in the present embodiment, the position of the (wheel 252 of the) first auxiliary support 250 with respect to the unicycle device 200 (when in the deployed configuration) defines a maximum allowable lean of the unicycle device 200 in a particular direction si before leaning of the device in that direction is restricted.

As the auxiliary support 250 moves from the retracted to the deployed configuration, the wheel of the auxiliary support moves in a direction substantially perpendicular to a side of casing 210 of the unicycle device 200, which lies in a plane of the wheel 220. Thus, the auxiliary support may move in a direction Si in which the unicycle device leans from side-to-side, which is also in a same plane in which the foot platform 265 rotates.

This enables the auxiliary device to provide a stronger and more consistent support to a leaning of the unicycle device. Moving the auxiliary device in this manner provides a more natural and controllable support to the user, as the auxiliary support moves in a direction in which a user leans in order to turn the unicycle. Thus, if a position of the auxiliary support is changed during a user's lean (e.g. to dynamically allow the user to lean a greater amount), the user would continue to receive support in substantially the same location with respect to a forward and rearward direction of the unicycle device. A predictability of the auxiliary support is thereby improved. There is also a greater and more predictable amount of control over the maximum allowable lean of the unicycle device, as the auxiliary support (which position defines the maximum allowable lean) moves in a same axis as the side-to- side lean. Thus, a position of the auxiliary support remains in relatively the same place with respect to a forward and backward direction of the unicycle device (i.e. a travel direction).

Moreover, such an embodiment ensures that the weight distribution or centre of mass) of the unicycle device in the fore-aft direction is maintained substantially the same as the auxiliary support moves. Thus, unintentional forward and rearward leaning of the unicycle device may be avoided, reducing unintentional acceleration/deceleration of the unicycle device as the auxiliary support deploys/retracts. This is of particular importance for an inexperienced or unpractised user of the unicycle device, who would not expect such changing acceleration.

In some examples (in which the auxiliary support is provided with a suspension unit or a dampener), the dampening will thereby be provided in the lean direction of the user. This increases the support perceived by a user and provides a more natural resistance to a user's leaning.

Preferably, the footprint or contact patch of the wheel(s) of the auxiliary support(s) lies along a same axis as the contact patch of the wheel of the unicycle device. In particular embodiments, the axis of rotation for the wheel(s) of the auxiliary support(s) lie in a same plane as the axis of rotation for the wheel of the unicycle device.

In this way, a mean position of the contact patches of the unicycle device may lie along a same axis as an axis of rotation of the wheel of the unicycle device.

Here, the term "contact patch" is used to refer to that portion of the wheel

220 or auxiliary support 250 which comes into contact with a ground surface. This contact patch may lie in a same position as a centre of the wheel 220 or of the wheel of the auxiliary support 250 respectively.

Even more preferably, a mean position or centre of the combined footprint or contact patch of the wheel(s) of the auxiliary support and the wheel of the unicycle device is located at a centre of the unicycle device. Thus, the average point of contact of the unicycle device is at a centre of the unicycle device. This ensures that a user is supported at a centre of the unicycle device, and thereby at the point about which a fore-aft balance is maintained. This increases a stability and control predictability of the unicycle.

Embodiments provide a unicycle device in which the centre of the contact points of the unicycle device (including the auxiliary wheels) is substantially at a centre of the unicycle device.

In some embodiments, all contact points of the unicycle device lie along a same axis. This axis and an axis about which the wheel of the unicycle rotates preferably lie in a same plane.

The auxiliary support may be substantially equidistant from a front end of the unicycle device and a rear end of the unicycle device. Such embodiments provide a greater freedom to a user of the unicycle device to move in the forward and rearward direction. Furthermore, these embodiments enable a more predictable control over the speed of the unicycle device, as rotation capabilities in the fore direction is maintained substantially the same as rotation capability in the rearward direction.

The unicycle device 200 may, in embodiments, be operable in a learning mode, wherein the position of the first auxiliary support with respect to the unicycle device depends upon, for example, a skill level of the user or a cumulative time of use of the unicycle device. In this way, the position of the (wheel(s) 252 of the) first auxiliary support 250 when in the deployed configuration may be altered.

In other words, there is proposed the concept of an auxiliary support which is adapted to vary its level of support based on a determined skill level of a user. A control system may control the auxiliary support (e.g. move a wheel of an auxiliary support) so as to change a maximum amount of tilt permitted before further tilting is restricted. The skill level of a user may be determined based on a number of factors including, for example, a speed of the unicycle device; a rate of change of side-to-side lean of the unicycle device; an acceleration of the unicycle device; a maximum speed attained by the user of the unicycle device and so on. In some embodiments, the user may be able to input a skill level to the unicycle device (e.g. using a user input unit later described). In such embodiments, the learning mode of the unicycle device may define the deployed mode of the unicycle, such that, dependent upon a skill level of the user, the deployed configuration may correspondingly vary.

In some embodiments, the position of the first auxiliary support (when in the deployed configuration) is dependent upon a user input received, for example, via wired connection or via a wireless communication technology such as Bluetooth. In this way, the user may control the position (e.g. of the wheel(s)) of the first auxiliary support relative to the unicycle device so as to allow the user to define a maximum allowable lean of the unicycle device in a particular direction. By way of example, the user may define the angle to which the pivotable arm 251 rotates when in the deployed position (e.g. the user may vary the angle between 60° and 120°). Thus such a unicycle device may enable a user to reconfigure or otherwise define a (retracted or deployed) configuration of the unicycle device.

This may advantageously allow a user to change an amount or position of support, providing stability to the device when required (i.e. when they lean beyond a safe amount). This will improve a user's confidence, and is particularly advantageous for the new or inexperienced user.

In other or further embodiments, the control system may be adapted to control the configuration of the auxiliary support in response to a user input received from a user. In other words, the user may be able to select in which configuration the auxiliary device operates. It will be apparent that the auxiliary support may be placed in different or other configurations than simply a retracted configuration or a deployed configuration (for example, a semi-deployed configuration or a partially deployed configuration).

Put simply, in embodiments, the user may control the configuration of the auxiliary support and/or define the retracted configuration and/or define the deployed configuration.

In some embodiments a unicycle device may comprise a user input unit adapted to receive a user input, so as to allow a user to control the configuration of the unicycle device. It will also be understood that the user need not comprise a person standing on the device, but may rather be an input received from, for example, a person standing next to a device or in the vicinity of the device. In some embodiments, the configuration of the auxiliary support may be controlled remotely (e.g. a parent may change the configuration of the auxiliary support).

In yet other embodiments, the user input unit may be adapted to receive a signal or indication from an authority (e.g. government, regulation body or local council) and the control system may be adapted to control the configuration based on the received signal.

In some further examples, the user input unit may be adapted to control or override a control parameter of the unicycle device based on the received signal or indication from the authority (e.g. to limit a maximum speed of the unicycle device).

When in the retracted configuration (FIG 6 A), the first auxiliary support is adapted to not readily couple the unicycle device 200 to a ground surface. Thus, a same lean si would not result in the first auxiliary support coupling the unicycle device to the ground surface. In other words, when in the retracted configuration, the first auxiliary support is adapted to permit a user to lean or tilt the device in the same direction Si for which leaning is restricted when in the deployed configuration.

When in the retracted configuration, the unicycle device 200 may have a greater manoeuvrability, as a greater lean of the unicycle device is permitted, reducing the turning circle of the unicycle device. When in the deployed configuration, the unicycle device may have a greater deal of support, such that a stability of the unicycle device is increased, reducing the likelihood that a user may fall off.

As used herein, the term restrict should be construed to mean that a further leaning of the unicycle device in the direction is prohibited or dampened. That is to say, further leaning may either be disallowed or reduced. For example, the auxiliary support (in the deployed configuration) may prevent or dampen a leaning of the unicycle device beyond a predetermined amount of lean. For example, the auxiliary support in the deployed configuration may allow a user to lean up to 10° from the vertical, but will prevent a leaning beyond 10° from the vertical.

It will be apparent that the first auxiliary support may comprise a suspension arrangement adapted to dampen a leaning of the unicycle device in a particular direction.

As shown in FIGS 6A-6C, unicycle device may comprise a second auxiliary support 255, which may, when in the deployed configuration, restrict a leaning of the unicycle deice in a generally opposing direction s₂ to that of the first auxiliary support 250. Preferably, the control system 260 controls the auxiliary support 250 and the additional auxiliary support 255 in the same manner, such that an equal amount of support is provided to a user on opposing sides of the unicycle device.

Put another way, there may be provided a concept of an auxiliary support

250, 255 comprising first auxiliary support 250 and a second auxiliary support. The first auxiliary support being associated with a first wheel 252 and the second auxiliary support being associated with a second wheel 257. The auxiliary support 250, 255 is adapted, when in the deployed configuration (FIG. 6B), to restrict a leaning of the device in at least two directions (e.g. first direction si and second direction s₂).

It is apparent that, in the present embodiment, the auxiliary support is adapted, when in the deployed configuration, to restrict a roll (si, s₂) of the unicycle device.

Preferably, the control system is adapted to control the first auxiliary support 250 and the second auxiliary support 255 in the same manner, such that the magnitude of a maximum allowable lean in a first direction si is substantially the same as a magnitude of a maximum allowable lean in a second direction s₂. It will be apparent, however, that in some embodiments the control of the first auxiliary support and the second auxiliary support is independent from one another.

The maximum allowable lean (in the first and/or second direction) may be, for example, no more than 20° from the vertical, for example, no more than 10° from the vertical, for example, no more than 5° from the vertical. Only allowing such a relatively small amount of lean may provide the new or unpractised user with a sufficiently high level of support to learn correct or effective operation of the unicycle device. For more experienced users, for example, the maximum allowable lean may be increased, for example, to no more than 30° from the vertical or even no more than 45° from the vertical. This would allow for an improved manoeuvrability of the device, as well as providing a reduced turning circle.

In preferable embodiments, the control system 260 is adapted to control the configuration of the auxiliary support 250, 255 between at least the retracted configuration (FIG 6A) and the deployed configuration (FIG 6B) based on a control parameter of the unicycle device. In other words, based on a measured or detected value associated with the unicycle device, the control system 260 may control the configuration of the auxiliary support.

In some examples, the auxiliary support may be placed in the deployed configuration in response to a measured speed or velocity of the unicycle device falling below a predetermined threshold (e.g. below 4mph/6.5kmph, below 2mph/3.2kmph etc.). This allows an increased level of support to be provided to the unicycle device at a low speed, as it may be more difficult for the user to maintain a side-to-side balance at such low speeds (e.g. due to a relative reduction in angular momentum / gyroscopic effect).

In some other examples, the auxiliary support may be placed in the deployed configuration in response to a measured torque falling below a predetermined threshold. This may allow for an increased level of support when it is detected, for example, that the unicycle is unable to maintain fore-aft balance successfully (e.g. due to a low battery level).

Similarly, the auxiliary support may be placed in the deployed configuration falling within a predetermined range of battery levels. By way of example, for a high or maximum battery, the control system may determine that a user intends to step on the unicycle device. In another example, when a low battery level is detected, the auxiliary support is placed in the deployed configuration (e.g. as a safety precaution).

In some embodiments, the auxiliary support may be placed in the deployed configuration in response to a difference between a desired control parameter and a current control parameter falling beneath a predetermined threshold (e.g. a difference between a desired velocity and a current velocity).

In other or further embodiments, the active (or current) configuration of the auxiliary support may depend on a signal received from a user detection system (not shown). Such a user detection system may be adapted to detect the presence of at least one foot of the user on the foot platform(s), and preferably is adapted to detect the presence of both the left foot and the right foot of the user on a respective platform. By way of example, if no user is detected or only a single foot of the user is detected, the auxiliary support may be placed in the deployed configuration (e.g. to support a user stepping on the device). If it determined that the user has both feet on the platforms, the auxiliary support may be placed in the retracted configuration. In this way, support for a user may only be provided when it is most needed (e.g. to mount the unicycle device).

In some embodiments, the active configuration of the auxiliary support may further or otherwise depend upon a time since power on of the device. By way of example, when a device is first powered on, the auxiliary support may be placed in the deployed configuration. After a predetermined period of time (e.g. 30 seconds, 1 minute, 5 minutes and so on) has elapsed, the control system may cause the the auxiliary support to enter the retracted configuration.

Exemplary control parameters which could be considered include: a speed of the unicycle device, a torque applied by the drive arrangement; an acceleration of the unicycle device; a fore-aft balance of the unicycle device; a direction of movement of the unicycle device a change in direction of movement of the unicycle device; an indication that the unicycle device has been powered on; an emergency or warning signal; a weight of the user; a stability of the unicycle device; a side-to-side balance of the unicycle device; a rate of change of side-to-side balance of the unicycle device; a signal from a gyrometer; a signal from an accelerometer; and a time since power on of the unicycle device.

In some embodiments, the auxiliary support may be deployed based on a direction in which the unicycle device is turning. For example, if the unicycle is turning to the right, a left auxiliary device (positioned on an opposing side to the turn) may be positioned in the deployed configuration. Such an embodiment is particularly advantageous for prevent a weaving motion of the unicycle device (e.g. as would be caused by the inexperienced user) as if a user makes a sudden change of incline, they may be supported by an auxiliary member.

In at least one conceivable embodiments, the unicycle device may further comprise an emergency deployment system (not shown) adapted to override the control system 260 and control the auxiliary support to be in the deployed configuration. By way of example, the emergency deployment system may detect when a dangerous or unsafe action has occurred (e.g. a power failure of the unicycle, a detected puncture, a motor failure, or an abrupt or unexpected stopping of the unicycle) and cause the auxiliary support to enter the deployed configuration. Such an emergency deployment system may comprise a spring-loaded emergency stop, adapted to automatically engage with the auxiliary support when a dangerous or unsafe action has occurred. Other suitably reliable emergency methods of deploying the auxiliary supports will be readily apparent to the person skilled in the art (e.g. magnetic or gravity-based techniques).

It will be readily apparent that the auxiliary support is not limited to only being placed in the retracted or the deployed configuration, but may be positioned in any arbitrary configuration. By way of example, there may be defined a maximum retracted configuration and a maximum deployed configuration (respectively corresponding to a minimum and maximum proximity of the wheel 252 with respect to the unicycle device 200). The auxiliary support may be positionable at any conceivable placement between these two configurations.

In at least one conceivable embodiment, the unicycle device 200 is adapted to maintain a side-to-side balance of the foot platform 265, thereby attempting to maintain the foot platform substantially horizontal with respect to a ground surface.

This may be performed, for by detecting an amount of side-to-side leaning of the unicycle device, and adjusting the configuration of the auxiliary support so as to restrict a leaning of the foot platform in the side-to-side direction. In such an embodiment, the balance control system may be adapted to determine an amount of side-to-side leaning (i.e. amount of roll si s₂) of the unicycle device 200.

To maintain the side-to-side balance of the foot platform 265, the position of the wheel 252 of the auxiliary support 250 relative to the foot platform may be automatically altered as the device leans from side-to-side, so as to maintain the foot platform horizontal relative to the ground surface. The foot platform may rotate about the unicycle device so as to permit the unicycle device to continue leaning in that direction, whilst the foot platform remains relatively level.

In other examples, the auxiliary support (e.g., when in the deployed configuration) may define a maximum angle of the foot platform 265 with respect to the unicycle device 200. At the maximum angle, the auxiliary support may restrict a further tilting of the foot platform, whilst allowing additional tilting of the unicycle device. That is to say, the auxiliary support 250 may cause the foot platform to rotate with respect to the unicycle device 265 at a maximum permissible lean of the unicycle device.

In some examples, the foot platform 265 is freely rotatable about the unicycle device 200, such that they do not support a user's weight by themselves. The auxiliary support 250 may be adapted to connect to the foot platform 265 to a ground surface, preventing the foot platform from further rotating about the unicycle device so as to support a user's weight.

The unicycle may be operable in a plurality of modes. These modes may include a learning mode, as previously described, a retracted mode (in which the auxiliary devices are maintained in a retracted configuration), a deployed mode (in which the auxiliary devices are maintained in a deployed configuration); a weave- prevention mode (in which an auxiliary support on a first side of the unicycle device deploys when the unicycle device is leaned towards a second, opposing side of the unicycle device); a user control mode (in which the position of the auxiliary supports is controlled by a user input); an emergency mode (in which the auxiliary supports are only deployed in response to an emergency signal) and so on. The unicycle may switch between these modes automatically (e.g. in response to a particular speed/acceleration/direction of the unicycle device or a (rate of) change in direction of the unicycle device or a time since power on of the unicycle device etc.). Alternatively, the unicycle device may switch between these modes in response to a user input (i.e. the user may control a mode of the unicycle device).

With reference now to FIG 7A-7B, another embodiment of a unicycle device 300 is shown, having a wheel 320, casing 310 and at least one foot support 365 (hereafter foot platform). In the present embodiment, there is identified an auxiliary support 350, 355 (comprising a first auxiliary support 350 and a second auxiliary support 355) and a control system 360.

As the first auxiliary support 450 and the second auxiliary support 455 operate in substantially the same manner, only the first auxiliary support shall be hereafter described.

As before, the first auxiliary support 350 comprises a first wheel 352. In order to control the position of the wheel 352, the first auxiliary support comprises a telescopic arrangement 351, which permits the wheel to be raised and lowered with respect to the foot platform 365. Thus, when in the retracted configuration, the telescopic arrangement 351 is retracted, and when in the deployed configuration, the telescopic arrangement 351 is extended. The telescopic arrangement may, for example, be controlled by a pneumatic or hydraulic actuating arrangement.

Thus, the movement of the auxiliary support (from the retracted to the deployed configuration) is in a plane substantially perpendicular to a plane in which the wheel of the unicycle device lies. That is, a plane substantially perpendicular to a fore-aft direction of the unicycle device.

FIG 7 A shows the first auxiliary support 350 in the retracted configuration, such that a leaning of the unicycle device 300 in a particular direction s₃ is not restricted (i.e. is permitted). FIG 7B shows the first auxiliary support 350 in the deployed configuration, in which a leaning of the unicycle device in the particular direction s₃ is restricted (i.e. leaning is not permitted).

It is apparent that when in the deployed configuration, a side-to-side leaning of the unicycle device is restricted.

The unicycle device 300 comprises a control system 360 adapted to control the first auxiliary support 350 and the second auxiliary support 355. The control system is adapted to control the first auxiliary support 350 to move from the restricted configuration to the deployed configuration. In other words, the control system 360 is adapted to control the telescopic arrangement 351 so as to raised and lower the wheel 352.

The second auxiliary support 355 operates in substantially the same way as the first auxiliary support, and is controlled by the same control system 360.

With reference to FIG 8A-8B, yet another embodiment of a unicycle device 400 may be described. The unicycle device comprises, as previously described, a casing 410, a wheel 420, a drive arrangement (not shown), at least one foot support 465, a balance control system (not shown) and an auxiliary support 450, 455. The auxiliary support comprises a first auxiliary support 450 and a second auxiliary support 455.

As the first auxiliary support 450 and the second auxiliary support 455 operate in substantially the same manner, only the first auxiliary support shall be hereafter described. The first auxiliary support comprises a first wheel 452 and an actuating member 451. The actuating member is adapted to permit raising and lowering of the first wheel 452 with respect to the foot platform 465, and comprises a first support member 4511, a second support member 4513 and a pivoting element 4512 adapted to pivotably connect the first support member 4511 to the second support member 4513.

FIG 8A shows the first auxiliary support in the retracted configuration, and FIG 8B shows the first auxiliary support in the deployed configuration. It is apparent that when in the deployed configuration, a side-to-side leaning of the unicycle device is restricted.

A control system (not shown) is adapted to control the raising and lowering of the first wheel 452 so as to enable control of auxiliary support between the retracted configuration and the deployed configuration. By way of example, the control system may comprise a cable, wire or other actuating system (not shown) connected to the second support member 4513, and adapted to move the second support member with respect to the foot platform. Other embodiments of a control system will be readily apparent to the person skilled in the art, for example, a gearing or differential system having a gear positioned in the pivotable member, may allow for the auxiliary support to be raised and lowered between the retracted and deployed configuration.

The present embodiment permits the wheel of the auxiliary support to be 'folded under' the foot platform, reducing an outward space occupied by the auxiliary support.

Other conceivable auxiliary supports may comprise a scissor mechanism or pantograph like arrangement adapted to allow raising and lowering of the auxiliary support.

With reference now to Fig. 9, a preferred embodiment of a powered unicycle device 500 having a single wheel 520 may be described. There is indicated the position of the drive arrangement 535 and the batteries 551, 552 of the unicycle device with respect to the single wheel. In other words, the drive arrangement and the batteries are positioned within the single wheel. The unicycle device 500 comprises an auxiliary support 550, 555 comprising a first auxiliary support 550 and a second auxiliary support 555, as previously described. The single wheel 520 of the unicycle device has a width wi greater than a standard or typical powered unicycle device. By way of example, the single wheel may have a width wi greater than 5cm, for example, greater than 10cm or 4 inches (10.16), for example, greater than 5 inches (12.7cm), for example, greater than 6 inches (15.24cm) and preferably greater than 7 inches (17.78cm).

In conceivable embodiments, the width of the wheel may be greater than 10 inches. In other or further embodiments, the width wi of the wheel may be no less than the radius of the wheel, and optionally no less than the diameter of the wheel.

Provision of a wider wheel permits for additional circuitry (e.g. drive arrangement 535 and batteries 551 to be fitted therein. This may allow, for example, increased power capacity of the unicycle device (as more batteries may be used) or increased power output of the drive arrangement (as a larger or more efficient drive arrangement may be used).

It has also been herein recognised that a wider wheel serves to improve the stability of the unicycle device. Furthermore, a wider tyre requires a user to stand (on the foot platforms) with a wider stance, further enhancing the stability of a user on the unicycle device. Such a wide tyre may also improve a safety of the device, as uneven ground (e.g. pavement cracks) is less likely to affect the direction of movement of the unicycle device.

Provision of an auxiliary support for a unicycle device having a wide wheel is particularly advantageous, as it reduces a difficulty of use or instability of the unicycle device. A user may be unused to the innovative concept of a wide wheeled device, and may have difficulty adapting to the change in stance required (e.g. wide stance). The support allows for even experienced, but unaware, users learn the operation of such a wide-tyred unicycle device, for example, improve an ease in mounting or turning the unicycle device.

It has been herein recognised that limiting the width of the wheel to be no less than the radius provides suitable stability for a new or inexperienced user to readily learn an operation of the unicycle device.

In even more preferable embodiments, the drive arrangement 535 comprises a hub motor 535 coupled to a rim 554 of the wheel 520, the rim having a tyre 525 mounted thereon. The hub motor may be connected, for example, via spokes 536 or plates. Suitable hub motors would be well known to the person skilled in the art.

In such a preferable embodiment, the batteries 551, 552, 553, 554 are positioned to lie between the axle of the hub motor and the rim 554 of the wheel 520, that is between the hub motor and the perimeter of the wheel 520. Preferably, the batteries are positioned to lie substantially parallel to the rim of the wheel (i.e. they lie along the width of the wheel 520).

In this way, the batteries 551, 552 may lie, for example, between spokes 536 of the wheel, providing an innovative positioning for the batteries, thereby allowing an increased density and size of the batteries of the uni cycle device 500.

By way of example, the batteries may comprise one or more 18650 lithium-ion battery cells positioned horizontally in the wheel. Such a wheel would have a width wi greater than 6.5cm so as to house the battery cells. In other words, the width of the wheel may be chosen so as to allow appropriate or preferred battery units to be positioned within the wheel. In some embodiments, therefore, the width of the wheel is dependent upon the type or size of the batteries positioned in the wheel.

With reference now to FIG 1 OA- IOC, an understanding of another preferred embodiment of a powered uni cycle device 600 may be elucidated. FIG 10A shows a top-down perspective of the powered unicycle device having an auxiliary support 650, 655 comprising a first auxiliary support 650 and a second auxiliary support 655. FIGS 10B and IOC exhibit the same powered unicycle device from a side-on perspective.

The first auxiliary support 650 may be arranged so as to restrict, when in the deployed configuration (FIG 10B), a fore and aft leaning of the unicycle device 600. The second auxiliary support may operate in a substantially same manner as the first auxiliary support.

It will be apparent from at least FIGS 10A-B, that the auxiliary support may restrict a leaning in the fore-and-aft direction. That is to say, there may be defined a maximum amount of lean in the fore-and-aft direction, after which further leaning of the unicycle device is restricted.

When the auxiliary support 650 is in the deployed configuration (FIG 10B), there may be defined a maximum allowable lean (e.g. in the fore-aft direction) beyond which further leaning of the unicycle device is restricted. When the auxiliary support 650 is in the restricted configuration (FIG IOC), the auxiliary support may permit the user to freely lean (e.g. without dampening or prevention) the unicycle device beyond the maximum allowable lean (associated with the deployed configuration). However, when in the restricted configuration, the auxiliary support may define an absolute maximum allowable lean, beyond which leaning of the unicycle device is prohibited.

In other words, there may be defined a first maximum allowable lean (associated with the deployed configuration) and a second maximum allowable lean (associated with the retracted configuration).

Provision of this second or absolute maximum allowable lean may ensure that safe operation of the unicycle device is maintained, so as to, for example, prevent excess leaning of the unicycle device beyond an acceptable or safe level.

It will be apparent that the auxiliary support, as described with reference to FIGS lOA-C, may also restrict a side-to-side leaning of the unicycle device (for example, when in the deployed configuration).

In preferable embodiments, the wheel(s) of the auxiliary support 650 are adapted to be angled with respect to the wheel 620 of the unicycle device 600. Preferably, the wheels are angled so as to point toward the wheel 620 of the unicycle device 600. Such embodiments allow for the auxiliary supports to 'steer' towards the wheel of the unicycle device, such that the unicycle device travels in substantially a same direction when the auxiliary supports are in a deployed configuration.

The unicycle device 600 may also comprise a lead 690 adapted to be held by or attached to a person. The lead may include a user input device 695 to allow a person to control a control parameter of the unicycle device. By way of example, the user input device 695 may allow a user to override a determined control parameter (e.g. a velocity) of the unicycle device.

The user input device may comprise a button, switch, touchscreen interface or other user interface to allow the user to interact with the unicycle device.

Such an embodiment may be particularly useful if a user is unable or unwilling to ride the unicycle (e.g. they are indoors, crossing a road, or riding over rough terrain), but does not wish the device to turn off or wish to carry the device. The user may simply control the device, using the user input device, so as to ensure the device follows or travels along with the user.

This may be particularly advantageous for a new or inexperienced user, as they may step off the device (e.g. if they reach terrain they do not feel comfortable with) and are not required to carry the device.

In some embodiments, the unicycle device is adapted to detect an angle at which the lead 690 is being held with respect to the unicycle device. The control system may be adapted to control a configuration of the auxiliary support based on the angle at which the lead is being held.

In some embodiments, the control system is adapted to control the configuration of individual elements of the auxiliary support in response to the detected angle. By way of example, the first auxiliary support may be put into a retracted configuration and the second auxiliary support may be put into a deployed configuration in response to the lead being held at a particular angle.

In this way, the auxiliary support may supplement or assist a turning or leaning of the unicycle device when the unicycle device is, for example, being towed by a user. In response to the lead being held at a particular angle, the auxiliary support may thereby cause the unicycle device to lean in a particular direction.

In some further embodiments, the auxiliary support may supplement a leaning of the unicycle device in response to the unicycle device leaning. That is to say, the auxiliary support may be placed in a configuration which causes the unicycle device to lean (e.g. a wheel(s) on a single side is positioned to contact a ground and lift the unicycle device so as to cause the unicycle device to lean).

In some conceivable embodiments, the user input device 695 comprises an accessory connector (not shown) adapted to connect to an accessory held by the user (e.g. a mobile phone or smart watch). The user input device may, for example, provide power to the connected accessory.

In yet other embodiments, the unicycle device may not comprise a lead, but rather may communicate with an accessory held by the user (e.g. a mobile phone) such that the user may control a control parameter of the unicycle device (e.g. a velocity) using the accessory. In other words, there may be a wireless communication between an accessory of the user and the unicycle device, the wireless communication comprising an indication of an intended or desired control parameter of the unicycle device.

As previously described, the user may be able to control the configuration of the auxiliary support using the accessory. In other words, the auxiliary support may be controlled between at least the retracted configuration and the deployed configuration in response to a user input received from an accessory (held by the user).

In other embodiments, the unicycle device may be adapted to allow the user to define the deployed and/or retracted configuration or a parameter of the deployed and/or retracted configuration. By way of example, the unicycle device may receive a user input (from an accessory, such as a mobile phone or smart watch, held by the user) and adjust a position of the wheel 252 of the auxiliary support 250 associated with a particular configuration. In other words, the unicycle device may be adapted to reconfigure a configuration based on at least a user input.

In yet other embodiments, the unicycle device may be adapted to reconfigure a configuration (e.g. change a position of the wheel associated with a particular configuration) based on a control or detected parameter of the unicycle device. By way of example, in response to the unicycle device travelling at a velocity above a predetermined threshold, the unicycle device may reconfigure the deployed configuration of the auxiliary support such that the proximity of the wheel 252 of the auxiliary support 250 is less proximate to a ground surface.

Suitable wireless communication protocols that may be used to allow the user to provide the unicycle device with a user input (for example, using an accessory held by the user) include an infrared link, ZigBee, Bluetooth, a wireless local area network protocol such as in accordance with the IEEE 802.11 standards, a 2G, 3G or 4G telecommunication protocol, and so on. Other formats will be readily apparent to the person skilled in the art.

In preferable examples, the unicycle device may be adapted to allow the user to change an amount of forward and backward leaning of the unicycle device (e.g. by adjusting the point about which a weight distribution of the unicycle device is measured). This may allow a user, for example, to tip the unicycle device 600 such that it rests on the auxiliary support 650 (see FIG. 10B). This would allow a user to control when the powered unicycle device is supported by the auxiliary support, even if a user is not standing on the powered unicycle device. Thus, a user may drag the unicycle device (e.g. using the lead) with ease.

The wheel(s) 651 of the auxiliary support 650, 655 may, in some embodiments, be motorized such that they are driven (e.g. by a respective motor arrangement). In particular, the motorized wheels may be controlled so as to correspond to a speed or velocity of the wheel 620 of the unicycle device 600. In other embodiments, the wheels are freewheeling, or operate on a flywheel basis.

The (balance control system of) unicycle device may be adapted to further control the fore-aft balance of the unicycle device by controlling an operation of the motorized wheels of the auxiliary support (i.e. drive the motorized wheels 651 back and forth along with the wheel 620 of the unicycle device). In yet further embodiments, the unicycle device may be adapted to detect a leaning of the unicycle device (from side-to-side) and control the motorized wheel so as to supplement a steering. In other or further embodiments, the unicycle device may be adapted to detect an intention to perform a turning manoeuvre (e.g. by detecting a sideways leaning), and control the motorized wheel based on the detected intention.

Motorized wheels are herein identified to at least reduce a drag of the unicycle device 600, and may improve power efficiency (as power will be distributed across both the wheel 620 of the unicycle device 600 and the wheel(s) 651 of the auxiliary support 650, 655.

A unicycle device 700 according to other embodiments of the invention may be described with reference to FIGS. 11 - 14. FIGS 11 and 12 illustrate unicycle devices 700 according to various embodiments having different numbers of auxiliary supports. FIGS 13 and 14 illustrate auxiliary supports suitable for use in the unicycle devices of at least FIGS 11 and 12. Of course, the unicycle device 700 may instead comprise any one or more auxiliary supports 350, 450, 550, 650 as previously described.

FIG 11 illustrates a top-down view of the unicycle device 700 having only two auxiliary supports. FIG 12 illustrates a top-down view of the unicycle device 700 having four auxiliary supports.

FIG 13 illustrates a rearward-forward view of the unicycle device 700 (of either of FIG 1 1 or 12) when viewed from the line xi-¾, having an auxiliary support according to one embodiment. FIG 14 illustrates a rearward-forward view of the unicycle device 700 (of either of FIG 11 or 12) when viewed from the line xi-x₂, having an auxiliary support according to another embodiment.

With reference to FIG 11, the unicycle device 700 comprises a wheel 720 and a foot platform 765 as previously described. The unicycle device 700 comprises a first auxiliary support 750 and a second auxiliary support 755. The first 750 and second 755 auxiliary supports may together form a single auxiliary support.

The auxiliary supports 750, 755 lie substantially equidistant from a frontward end 740 and rearward end 741 of the unicycle device 700. Thus, a distance yi between the auxiliary support 750 and the frontward end 740 of the unicycle device 700 is substantially same a distance y₂ between the auxiliary support 750 and a rearward end of the unicycle device 700.

In particular, the auxiliary supports 750, 755 lie in a plane which is both perpendicular to a fore-aft direction y of the unicycle device 700 and which intersects an axis xi, x₂ about which the wheel 720 rotates. In some embodiments, and as will be apparent from the following description, the auxiliary supports are adapted to move between the retracted and deployed configuration in this same plane. The operation of the auxiliary supports may be simultaneous or independent from one another. For example, if a user leans the unicycle to a right in order to turn the unicycle device, it is possible to deploy an auxiliary device positioned on the left of the unicycle. This may, for example, prevent or reduce a weaving of the unicycle device.

With reference to FIG 12, the unicycle device 700 may comprise a wheel 720, and a foot platform 765 as previously described. The unicycle device 700 of FIG 12 also comprises an auxiliary support 750, 755, 756 757 which will be hereafter described.

In such an embodiment, the auxiliary support comprises a first auxiliary support 750, a second auxiliary support 755, a third auxiliary support 756 and a fourth auxiliary support 757. The first 750 and third 756 auxiliary support may be positioned on a first same side of the unicycle device 700, and the second 755 and fourth 757 auxiliary support may be positioned on a second same side, the second same side opposing the first same side. The first 750 and second 755 auxiliary support may be positioned to oppose one another, and the third 756 and fourth 757 auxiliary support may be positioned to oppose one another. In other words, when viewed from above, the auxiliary support may have a reflective symmetry.

It will be clear that, in an embodiment, the unicycle device may comprise only three auxiliary supports.

Each of the first, second, third and fourth auxiliary support may be together considered as a single auxiliary support. In particular, they may be considered as a single auxiliary support having a first, second, third and fourth wheel. Each wheel of such an auxiliary support may be independently controlled, and have a plurality of respective configuration associated therewith.

Provision of the four auxiliary supports as described above may advantageously improve a stability of the unicycle device. Having an additional four points of contact (i.e. in addition to the wheel 720 of the unicycle device) with the earth may prove particularly beneficial in maintaining a high level of support and suspension to a user of the unicycle device.

As before, the auxiliary support is controllable between at least a retracted configuration and a deployed configuration, in the same manner as previously described.

As illustrated in FIG 12, a centre of the combined footprint (i.e. contract patch) of the unicycle device and auxiliary support(s) is located at a centre of the unicycle device. This provides a more even distribution of support for a user of the unicycle device.

With reference now to FIG 13, an auxiliary support 750 according to an embodiment will be described. The auxiliary support 750 is suitable for use in any unicycle device previously described, in particular, the unicycle devices illustrated in FIGS 11 and 12. As illustrated, the auxiliary support 750 comprises a wheel 752 coupled to the foot platform 765 of the unicycle device 700 via a first coupling member 7521. The wheel 752 is rotatably coupled to the first coupling member 7521 and the first coupling member is rotatably coupled to the foot platform 765.

The auxiliary support 750 further comprises a second coupling member 7522 rotatably coupled at a first end to the first coupling member 7521 and at a second end to the foot platform 765. Furthermore, the second end of the second coupling member is slidable or movable along the foot platform 765.

The unicycle device comprises a control system 760 adapted to control a position of the second end of the second coupling member with respect to the foot platform. By way of example, the control system may slide the second of the second coupling member along the foot platform.

Movement of the second member along the second foot platform causes both the first coupling member 7521 and the second coupling member 7522 to rotate about the foot platform. This, in turn, causes a raising and a lowering of the wheel 751 of the auxiliary support.

It will be apparent that a raising or lowering of the wheel of the auxiliary support controls the configuration of the auxiliary support. In some embodiments, when the auxiliary support is in the retracted configuration, the wheel is raised, whereas when in the deployed configuration, the wheel is lowered.

The sliding of the second coupling member (i.e. along the receiving member) may be performed by, for example, a worm-drive. The worm-drive may thereby control a raising or lowering of the wheel with respect to the unicycle device.

A control arrangement may be adapted to control an operation of the worm drive, for example, in response to a user input or a control parameter of the unicycle device. Such a control arrangement may be adapted to generate signals which control an operation of the worm drive.

The auxiliary support 750 is adapted to move (between the retracted and deployed configuration) in a plane perpendicular to a forward and rearward direction of the electric unicycle. That is, in a plane perpendicular to a plane in which the wheel 720 of the unicycle device lies.

The axis along which the second coupling member 7522 moves may be substantially parallel to an axis about which the wheel 720 of the unicycle device rotates.

With reference now to FIG 14, a modification to the previous embodiment of the auxiliary support for the unicycle device will be described. In the described embodiment, the second coupling member 7522 may be immovable with respect to the foot platform 765, but the first coupling member 7521 may be adapted to be slidable or movable along the foot platform 765.

It will be apparent that a sliding of the first coupling member 7521 causes the first coupling member 7521 and the second coupling member 7522 to rotate with respect to the foot platform, thereby raising and lowering the wheel 751 of the auxiliary support 750. In other words, a configuration of the auxiliary support may be controlled by a sliding of the first coupling member with respect to the foot platform.

Of course, it will be readily apparent that in some embodiments both the first and the second coupling member may slide or move along the foot platform 765 so as to cause a lowering or raising of the wheel 751 of the auxiliary support 750.

As shown in FIGS 11-14, in some embodiments, the wheel of the auxiliary support may be positioned to lie substantially beneath or in line with the foot platform or support of the unicycle device. This may advantageously provide an improved level of support to a user standing on the unicycle device.

Preferably, the width of the wheel 751 of the auxiliary support 750 is less than or equal to a depth of the foot platform 765. In some embodiment, when in the retracted configuration, the wheel is adapted to be positioned alongside or within (e.g. a void of) the foot platform 765. This reduces a profile of the unicycle device.

In preferable embodiments, the auxiliary support, when in the retracted configuration, acts to protect the foot platform from contact with a ground surface at extreme lean angles of the unicycle. This is illustrated in FIG 14, in which the wheel of the auxiliary support 755 (in a retracted configuration) is in line with and alongside the foot platform 765. Thus, when the wheel is heavily tilted in the direction of the auxiliary support 755, the wheel comes into contact with a ground surface and rolls along the ground surface, rather than the foot platform.

This significantly improves a safety of the unicycle device, especially at extreme angles of lean, as the foot platform is no longer able to come into contact with a ground surface. Should the foot platform come into contact with a ground surface, this would result in significant drag and may cause the unicycle device to perform an unpredictable turn. By ensuring that the wheel of the auxiliary support (even in the retracted configuration) protects the foot platform, an extremely tight turning circle can be achieved without affecting the safety of the user. This also prevents damage to the unicycle device, and the foot platforms in particular.

FIG. 15 illustrates another conceivable embodiment of a unicycle device 800, in which when in the deployed configuration, the auxiliary support 850 is adapted to lift the wheel 820 of the unicycle device 800 off a ground surface, such that the unicycle device 800 is solely supported by the auxiliary support 850. In other words, when the auxiliary support is in the deployed configuration, the wheel of the unicycle device may not be in contact with a ground surface or be unable to come into contact with the ground surface.

The wheel may be lifted off the ground surface, for example, by a predetermined height hi.

This allows the unicycle device to move independently of the wheel of the unicycle device. In other words, when the auxiliary support is in the deployed configuration, the unicycle device may freewheel without input from the drive arrangement. Thus, when the auxiliary support is in the deployed configuration, the unicycle device may act in a manner similar to a skateboard, such that a user must self-propel themselves, rather than relying on controlling the drive of the unicycle device.

In preferable such embodiments, the auxiliary support comprises at least three wheels (i.e. at least a first auxiliary support, a second auxiliary support and a third auxiliary support). This would provide a sufficiently stable base for a user to self- propel themselves.

Preferably the wheel of the unicycle device is lifted on the ground surface in response to an emergency signal or an emergency situation being detected (e.g. a power cut-off to the drive arrangement of the unicycle device).

The internal components of the unicycle devices illustrated in FIG 13 to 15 (e.g. a battery, PCB or other components) or otherwise previously described may be positioned externally to the wheel, rather than being formed within an envelope of the wheel (as illustrated in the FIGS). This may, for example, allow for a wheel of reduced size and weight.

In some conceivable embodiments, the auxiliary support may remain in the same position relative to a ground surface or the unicycle device (i.e. not change a position), but have a varying hardness of suspension or dampening. By way of example, in the deployed configuration, the control system may control the suspension or dampening provided by the auxiliary support may be hard or high, such that the unicycle device has a restricted leaning in at least one direction. Whereas in the retracted configuration, the control system may control the suspension or dampening to be soft or low, such that the unicycle device is prevented from leaning in the at least one direction.

It will also be readily apparent that an auxiliary support, according to an embodiment of the inventive concept, need not comprise a wheel. Rather, the auxiliary support may be considered to act as a stand for the unicycle device, or alternatively, a skid pad.

In some embodiments the foot support(s) or platform(s) may be adapted to not rotate with respect to the unicycle device such that the foot support(s) stays at a same angle with respect to the unicycle device. Such an embodiment may advantageously provide an increased level of support to a user when being support by the auxiliary support (as the foot platform will not attempt to fold against the unicycle device).

Although the auxiliary support of described embodiments comprises both a first auxiliary support and a second auxiliary support, it will be apparent that some embodiment may include only a single auxiliary support. Such an embodiment may be useful to allow a user to more easily mount the unicycle device (i.e. support the unicycle device when a first foot is placed on it). It has been herein recognised that placement of a single foot on the unicycle device may destabilise the unicycle device, such that an auxiliary support would be of use.

In at least one embodiment, the movement of the auxiliary support between the deployed and retracted configuration may be in a plane substantially perpendicular to a forward and rearward direction of the unicycle device. That is, in a plane in which the unicycle device may lean from side-to-side. Such an embodiment would provide a stronger and more reliable support for a user leaning from side to side.

Preferably, the auxiliary support(s) is adapted to be directly coupled to a foot platform or foot support. This provides the greatest amount of support to a user.

Even more preferably, the unicycle device comprises a pair of foot supports, for a respective foot of a user, and a respective pair of auxiliary supports. Each auxiliary support is directly connected to a respective foot platform, in order to provide the greatest amount of support to a user in both directions in which a user may lean in order to turn the unicycle device. That is, using a pair of auxiliary supports, each auxiliary support coupled to a respective foot platform, provides the user with the greatest amount of support in a side-to-side leaning of the unicycle device.

In at least one embodiment, the axis about which a wheel of the auxiliary device rotates (when in a deployed configuration) is a same axis about which the wheel of the unicycle rotates. In this embodiment, the wheel of the auxiliary device may have a smaller diameter than the wheel of the unicycle device, such that the wheel of the auxiliary support only comes into contact with a ground surface when inclining the wheel. In the retracted configuration, the wheels of the auxiliary device may be positioned more proximate to the wheel (e.g. hidden) such that the user is able to lean at a greater angle (from side-to-side) than allowed when the wheel of the auxiliary device is in the deployed configuration.

Provision of at least one auxiliary support may negate the need for leg contacts, as the auxiliary support (in a deployed configuration) allows the user to mount the unicycle needing to brace using their legs. This is considered a significant problem with current unicycle devices. The auxiliary supports may be retracted after operation of the unicycle device has begun, to thereby enable the full benefits of a unicycle device (e.g. increased manoeuvrability and reduced likelihood of disrupted travel) to be realised.

Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope. Combinations of features in embodiments herein described may be used to various advantages.

Claims

1. A self-balancing powered unicycle device comprising:

a wheel;

a drive arrangement adapted to drive the wheel;

at least one foot support for supporting a user;

a balance control system adapted to maintain fore-aft balance of the unicycle device by controlling the drive arrangement;

an auxiliary support controllable between at least a deployed configuration, in which the auxiliary support restricts a leaning of the unicycle device in at least one direction, and a retracted configuration, in which the auxiliary support permits a leaning of the unicycle device in the at least one direction; and

a control system adapted to control the auxiliary support from the retracted configuration to the deployed configuration.

2. The self-balancing powered unicycle device of claim 1, wherein the control system is adapted to control the configuration of the auxiliary support based on at least one control parameter of the powered unicycle device.

3. The self-balancing powered unicycle device of claim 2, wherein the control parameter is at least one of: a speed of the unicycle device, a torque applied by the drive arrangement; an acceleration of the unicycle device; a fore-aft balance of the unicycle device; a direction of movement of the unicycle device; a change in direction of movement of the unicycle device; an indication that the unicycle device has been powered on; an emergency or warning signal; a weight of the user; a stability of the unicycle device; a side-to-side balance of the unicycle device; a rate of change of side- to-side balance of the unicycle device; a signal from a gyrometer; a signal from an accelerometer; and a time since power on of the unicycle device.

4. The self-balancing power unicycle device of any preceding claim, wherein a movement of the auxiliary support between the retracted configuration and the deployed configuration is in a plane substantially perpendicular to a fore-aft direction of the unicycle device.

5. The self-balancing powered unicycle device of any preceding claim, wherein the auxiliary support comprises at least one wheel positionable with respect to the unicycle device.

6. The self-balancing powered unicycle device of claim 5, wherein the control system is adapted to control the proximity of the at least one wheel to a ground surface, wherein the at least one wheel is more proximate to the ground surface when in the deployed configuration than when in the retracted configuration.

7. The self-balancing powered unicycle device of any of claims 5 or 6, wherein the at least one wheel of the auxiliary support is angled with respect to the wheel of the unicycle device.

8. The self-balancing powered unicycle device of any preceding claim, further comprising a user input unit, the user input unit being adapted to receive a user or authorities input and, based on the received user input, control the configuration of the auxiliary support.

9. The self-balancing powered unicycle device of any preceding claim, wherein the auxiliary support comprises a first wheel and a second wheel, the first and second wheel being positioned on opposite sides of the unicycle device.

10. The self-balancing powered unicycle device of claim 9, wherein the auxiliary support further comprises at least a third wheel and optionally a fourth wheel,

optionally wherein the third wheel is positioned on the same side as the first wheel and the fourth wheel is positioned on the same side as the second wheel.

11. The self-balancing powered unicycle device of any preceding claim, wherein the auxiliary support is coupled to the at least one foot support.

12. The self-balancing powered unicycle device of any preceding claim, wherein the auxiliary support is adapted to perform at least one of the following:

in the deployed configuration, to restrict a side-to-side leaning of the powered unicycle device;

in the deployed configuration, to restrict a fore-and-aft leaning of the powered unicycle device; and

in the retracted position, to restrict a fore-and-aft leaning of the powered unicycle device.

13. The self-balancing powered unicycle device of any preceding claim, wherein the control system is adapted to control the auxiliary support so as to be in deployed configuration in response to the powered unicycle device being powered on.

14. The self-balancing powered unicycle device of any preceding claim, wherein the auxiliary support comprises at least one motorized wheel.

15. The self-balancing powered unicycle device of claim 14, wherein the balance control system is adapted to perform at least one of the following:

maintain fore-aft balance of the unicycle device by further controlling at least one motorized wheel of the auxiliary support; and

steer the unicycle device by further controlling at least one motorized wheel of the auxiliary support

16. The self-balancing powered unicycle device of any preceding claim, wherein the width of the wheel of the unicycle device is greater than 5cm.

17. The self-balancing powered unicycle device of any preceding claim, further comprising a lead.

18. The self-balancing powered uni cycle device of claim 17, wherein the lead comprises a control unit adapted to allow a user to control or override a control parameter of the unicycle device.

19. The self-balancing powered unicycle device of any of claims 17or 18, further comprising a lead angle detection unit adapted to detect an angle of the lead with respect to the unicycle device, and wherein the control system is adapted to control the configuration of the auxiliary support based on the detected angle of the lead.

20. The self-balancing powered unicycle device of any preceding claim, wherein the drive arrangement comprises a hub motor, and further comprising batteries positioned between the axle of the hub motor and the perimeter of the wheel.

21. The self-balancing powered unicycle device of claim 20, wherein the batteries lie wholly within the envelope of the wheel.

22. The self-balancing powered unicycle device of any preceding claim, further adapted to maintain a side-to-side balance of the at least one foot support.

23. The self-balancing powered unicycle device of any preceding claim, wherein, when the auxiliary support is in the deployed configuration, the wheel of the unicycle device is not able to come into contact with a ground surface.

24. The self-balancing powered unicycle device of any preceding claim, wherein the control system is adapted to control the auxiliary support so as to be in deployed configuration in response to a dangerous or unsafe event of the unicycle device being detected.

25. The self-balancing powered unicycle device of any preceding claim, wherein a mean position of the contact patches of the wheel and the auxiliary support is at a centre of the unicycle device.

26. The self-balancing powered unicycle device of any preceding claim, wherein a mean position of the contact patches of the wheel and the auxiliary support lies in a same plane as an axis about which the wheel rotates.