GB2585241A

GB2585241A - Augmented reality system

Info

Publication number: GB2585241A
Application number: GB1909686.6A
Authority: GB
Inventors: Finn Tom; Barksfield Rupert
Original assignee: Magic Lines Ltd
Current assignee: Magic Lines Ltd
Priority date: 2019-07-05
Filing date: 2019-07-05
Publication date: 2021-01-06
Anticipated expiration: 2039-07-05
Also published as: GB201909686D0; GB2585241B

Abstract

The augmented reality system comprises a display and is arranged to determine the user's current position, to determine a safe or optimum path from the user's current location to a desired destination, determine if there are any hazards or unmapped areas, provide an augmented reality overlay over a user's field of vision which visually masks or obscures any hazards or unmapped areas which might distract, attract or confuse the user, and the system overlays a series of transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination. The display may be a headset or glasses. Where transverse bars are overlaid, they may be adapted in proportion with a user’s height or gait. The system may use gamification and reward points or other feedback after the user has progressed walking over or towards one or more of the visual cues. The apparatus may assist a user with Parkinson’s disease achieve increased mobility by navigating a particular space when experiences freezing of gait (FOG). Multiple people may be able to use systems in the same area. The system may be used with or without a nurse or practitioner.

Description

AUGMENTED REALITY SYSTEM

CROSS-REFERENCE TO RELATED APPLICATION None.

FIELD OF THE INVENTION

The present invention relates generally to augmented reality systems. The preferred embodiment relates an augmented reality system for assisting a user who experiences freezing of gait ("FOG").

BACKGROUND

In advanced disease stages most people with Parkinson's disease ("PD") will experience freezing of gait ("FOG"). Freezing of gait remains one of the most common debilitating aspects of Parkinson's disease and causes temporary cessation of effective stepping and a sensation of being stuck to the ground. To-date pharmacological and surgical intervention has been found to be ineffective in overcoming such symptoms.

Freezing of gait can be particularly pronounced when a person seeks to make a turn, initiate walking or walk through a confined space. In particular, gait initiation failure or start hesitation is a component of freezing of gait which is effectively the difficulty in initiating gait. Freezing of gait negatively impacts mobility and independence and can cause confusion and emotional stress in a patient resulting in a reduced quality of life.

It has been observed that whilst people suffering with Parkinson's disease may struggle with self-directed movement such as walking, other activities which involve more goal directed movement may remain relatively unaltered.

In response to this recognition, experiments have been performed wherein external cues are provided to a person with Parkinson's disease in order to assist them to overcome freezing of gait. In particular, it is known to provide a pattern of coloured stripes on the floor which provide visual cues to the person. A physiotherapist working with a patient may, for example, use line markers on the floor which can act as a visual cue. The patient suffering from Parkinson's disease is encouraged to walk on these visual cue points and this strategy has been found to be effective.

Research is on-going in order to gain a deeper understanding as to why the provision of sensory cues to a person experiencing freezing of gait is effective.

Whilst providing physical coloured markers on the floor has been found to be effective, it will be apparent that the current approach is relatively basic and time consuming. The current approach also requires a person physically to set up the markers -2 -and then remove the markers after the task is performed or the session is completed. Furthermore, the current approach assumes that only a single person is seeking to navigate a particular space at any particular time.

It will be appreciated that if multiple people are seeking to navigate a particular space at the same time (for example, patients in a care home or hospital environment) then the conventional approach of placing physical stripes on the floor no longer works as it would be too confusing when multiple people were seeking to navigate the same physical space at the same time.

Furthermore, in order to be effective the physical stripes on the floor need to be provided in a particular (horizontal) orientation to the user so that they appear as transverse bars or horizontal lines. It has also been found that different users can respond differently to the same physical stripes and hence an arrangement which works for one patient may be less effective for another patient and vice versa.

It is desired therefore to provide an improved method of helping users who experience freezing of gait and in particular to provide an improved method of assisting someone who experiences freezing of gait such that they can be enabled to navigate a particular space in a safe manner potentially at the same time as other people.

SUMMARY

According to an aspect of the present invention there is provided an augmented reality system for assisting a user who experiences freezing of gait, wherein the augmented reality system comprises a display for providing an augmented reality overlay over a user's field of vision and wherein the augmented reality system is arranged and adapted: (i) to determine the user's current position; (ii) to determine a safe or otherwise optimum path from the user's current location to a desired destination; (iii) to determine if there are any hazards or unmapped areas in the vicinity of the user's current location; (iv) to provide an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user and wherein the augmented reality overlay also comprises a series of transverse bars, images or visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination; -3 - (v) to provide a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or unmapped area; and (vi) to vary one or more visual aspects of the transverse bars, images or visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars, images or visual cues towards the desired destination.

The augmented reality system according to the present invention is particularly advantageous compared with the known approach of placing physical stripes on the floor in front of the user. The augmented reality system according to the preferred embodiment does not require a nurse, assistant or practitioner to be physically present. Furthermore, the augmented reality system according to the preferred embodiment can tailor and optimise a number of features and parameters for the specific user in a manner which is not readily possible with the conventional approach of using physical stripes placed on the floor in front of the user or patient.

The augmented reality system according to the preferred embodiment is particularly flexible and adaptable and enables a user to be guided to a desired destination in a safe or otherwise optimal manner.

Hazards or unmapped areas can be avoided. In particular, whereas according to the conventional approach a user may be distracted or confused by certain hazards or other objects around them, according to the preferred embodiment potential distractions can be masked or at least partially obscured so that the user can focus on the task of walking from their current location to the desired destination.

According to the preferred embodiment a sensory warning is provided to the user if the user starts to deviate from the desired path or if the user begins to approach a hazard.

These are additional benefits compared with the conventional approach.

The augmented reality system according to the preferred embodiment also allows the display of transverse bars, images or other visual cues to be varied as the user or patient progresses towards the desired destination. Accordingly, the user or patient can be provided with an experience where they may be rewarded visually, audibly or in some other manner as the user make progress thereby encouraging the user to continue walking forwards and making the overall experience more pleasurable and rewarding to the user, thereby encouraging the user to use the system another time.

In particular, as will be discussed in more detail below, the user may be provided with a gamified experience which encourages the user to use the augmented reality system and which provides an element of enjoyment and sense of progress to the user.

The ability to introduce one or more elements of a game into the experience has been -4 -found to result in users actively wanting to use the system and to continue making progress in walking towards a desired destination when otherwise they might give up, become distracted or relapse into experiencing freezing of gait.

Accordingly, the provision of a gamified experience has been found to be particularly advantageous in helping a user overcome freeing of gait.

The augmented reality display preferably comprises a headset or glasses. Other display apparatus may also be used. The augmented reality system preferably involves a user wearing a pair of glasses (or a headset) through which they can see real world images as they would with normal glasses. However, with augmented reality ("AR") digitally produced images are additionally presented or superimposed upon the real world images which the user is viewing or seeing. Accordingly, the real world images which a user views or sees are augmented or enhanced so that additional digital information or images are overlaid or superimposed upon the user's field of view. Accordingly, an AR system differs from a virtual reality ("VR") system in that with an AR system there is a degree of transparency or overlap in that digitally produced images are superimposed upon or provided in addition to real world images which the user is seeing.

Stereoscopic headsets or wearable glasses may be used in both VR and AR systems and generally feature two displays -one display is normally intended for the left eye and one display is normally intended for the right eye. The two displays are configured to display digital images with slightly different element presentation such that a three-dimensional perspective is perceived by the human visual system. VR and AR systems are generally capable of displaying virtual digital content at various perceived positions and distances relative to the user.

The augmented reality system is preferably arranged and adapted to set the distance between the transverse bars, images or visual cues either: (i) in proportion to the user's height; (ii) in proportion to the user's average gait; or (iii) in response to a user specific setting. Various aspects of the transverse bars, images or visual cues can be readily set and personalised according to the preferred embodiment in a manner which is not possible with the conventional approach. Furthermore, aspects of the transverse bars, images or visual cues can be changed, developed or enhanced as the user makes progress in walking thereby providing the user with a gamified experience which encourages the user to continue walking towards a desired destination.

Setting various parameters relating to the display of the transverse bars, images or visual cues is advantageous since it enables the visual cues which are provided to a user or patient to be readily personalised dependent upon, for example, the physical characteristics of the user. Accordingly, it will be apparent that according to the conventional approach it may not be possible to leave physical markers on the floor in a -5 -room which is being used by more than one person or patient. For example, a first person or patient may be particularly tall in which case it may be desirable for there to be a relatively large spacing between adjacent transverse bars, images or visual cues. A second person or patient may be particularly short in which case it may be desirable for there to be a relatively short spacing between adjacent transverse bars, images or visual cues. Accordingly, two users or patients seeking to navigate the same path at different times may require different arrangements of transverse bars, images or visual cues having different spacings. It will be apparent that this is not readily possible with the conventional manual approach.

The augmented reality system is preferably arranged and adapted to reset or rotate the position and/or direction of travel of the transverse bars, images or other visual cues in order to encourage or assist the user to change direction or turn a corner.

It is known that people who suffer from freezing of gait have particular problems when it comes to changing direction or seeking to turn a corner when walking. It is difficult to arrange physical stripes on the floor in a manner which enables a user to turn a corner.

Whilst a user may step on the physical stripes on the floor and move forwards in a linear direction, the user may then freeze if the physical stripes on the floor are presented at an angle to the user.

According to various embodiments of the present invention the augmented reality system may project a series of transverse bars, images or other visual cues which extend in a linear manner (rather than a curved manner) in front of the user but as the user progresses, the augmented reality system may progressively rotate the series of transverse bars, images or other visual cues in a subtle or imperceptible manner. Accordingly, whilst a user continues to see a linear (horizontal) arrangement of transverse bars, images or other visual cues which extend forward in front of them, the orientation of the series of transverse bars, images or other visual cues may be progressively rotated as the user moves forwards thereby enabling the user to turn a corner without suffering from freezing of gait.

The augmented reality system is preferably arranged and adapted to set the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues at a first setting in order to encourage or assist the user to initiate walking forwards following the series of transverse bars, images or visual cues.

The augmented reality system may be arranged and adapted to vary the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues at a second different setting once a user has commenced walking forwards following the series of transverse bars, images or visual cues. -6 -

Varying the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues as the user commences walking forwards and as the user makes progress may be part of providing the user with a gamified user experience wherein the user is rewarded with positive sensory feedback as they start out walking and continue to make progress in walking forwards.

Various embodiments are contemplated wherein the augmented reality system changes the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues as the user progresses. For example, initially a first colour palette may be used to encourage the user to initiate walking which may change as the user progresses. Also, various gamification features may be incorporated so that as a user progresses the intensity of the transverse bars, images or visual cues or other sensory feedback may increase in order to give the user a sense of progress and reward for progress.

The augmented reality system is preferably arranged and adapted to monitor the progress of the user and to vary the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues in the event that the augmented reality system determines that the user is struggling or faltering to walk forwards following the series of transverse bars, images or visual cues.

For example, if the augmented reality system determines that the user is struggling or faltering to walk forwards various gamification features such as visual and/or audible encouragement may be deployed in order to catch the attention of the user, to filter out possible distractions and to help encourage the user to continue walking forwards.

Various embodiments are contemplated wherein the augmented reality system constantly monitors the progress of the user. If the augmented reality system determines that the current augmented reality visual overlay which is provided to the user is not being effective in aiding the user to progress, then the system may alter one or more parameters of the visual cues which are provided to the user with the aim of seeing whether different visual settings are effective for the user or patient.

The augmented reality system is preferably arranged and adapted to monitor the progress of the user and to test different colours and/or intensities and/or spacings and/or widths of the transverse bars, images or visual cues in order to determine optimum user specific colours and/or intensities and/or spacings and/or widths of the transverse bars, images or visual cues which have the effect of encouraging or assisting the user to walk forwards following the series of transverse bars, images or visual cues in an optimum manner.

The augmented reality system is preferably arranged and adapted to generate one or more audible cues. The one or more audible cues preferably comprise one or more -7 -sounds or noise triggers as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars, images or other visual cues. In particular, the one or more audible cues may encourage the user to continue walking forwards and optionally may also warn the user if they begin to approach a potential hazard or an unmapped area.

The augmented reality system is preferably arranged and adapted to display a points total or progress indicator, wherein as a user progresses walking over or towards the one or more of the transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user, the augmented reality system displays an updated or increased points total or progress indicator.

For example, the points total or progress indicator may increase in value after the user reaches each transverse bar, image or other visual cue. Some transverse bars, images or other visual cues may provide a greater points reward or progress indicator than others. It is contemplated, for example, that a user may receive a certain points reward or indication of progress after walking across the first few transverse bars, images or other visual cues. The points which are rewarded or the progress indicator may increase as the user makes further progress.

The display of a points total or progress indicator is an example of a gamification feature which encourages a user to make progress and gain confidence using the system.

Gamification is an important aspect of the preferred system and it has been found that introducing such features encourages users to interact with the system.

The augmented reality system may be arranged and adapted to award the user with additional points or other indication of progress as the user walks over or towards the one or more transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user.

The award of additional points or other indication of progress helps to provide the user with an enhanced gamified experience where the user is encouraged to enjoy the experience of walking forward in an analogous manner to playing a game.

The augmented reality system may be arranged and adapted to display one or more reward icons or pop-up images and/or provide other sensory feedback after the user has progressed walking over or towards the one or more of the transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user.

According to various embodiments the reward icons or pop-up images and/or the provision of other sensory feedback may only be provided to the user after the user has made some initial progress. It is contemplated, for example, that no reward icons or pop-up images are initially provided to a user whilst the user crosses the first few transverse bars, images or other visual cues. However, after the user has made some initial progress -8 -they may then be rewarded with one or more reward icons or pop-up images and/or the provision of other sensory feedback.

The display of one or more reward icons or pop-up images and/or the provision of other sensory feedback after the user has progressed walking helps to provide the user with an enhanced gamified experience where the user is encouraged to enjoy the experience of walking forward in an analogous manner to playing a game. The other sensory feedback which may be provided includes audible and/or tactile feedback. For example, the display of one or more reward icons or pop-up images may be accompanied with a sound or chime. The augmented reality system may alternatively or additionally provide feedback to the user by, for example, causing a controller or other device to vibrate.

According to another aspect there is provided a method of assisting a user who experiences freezing of gait comprising displaying an augmented reality overlay over a user's field of vision, wherein the method further comprises: (i) determining the user's current position; 00 determining a safe or otherwise optimum path from the user's current location to a desired destination; (iii) determining if there are any hazards or unmapped areas in the vicinity of the user's current location; (iv) providing an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user and wherein the augmented reality overlay also comprises a series of transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination; (v) providing a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or unmapped area; and (vi) varying one or more visual aspects of the transverse bars, images or other visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars or other images towards the desired destination According to another aspect of the present invention there is provided an augmented reality system for assisting a user who experiences freezing of gait, wherein the augmented reality system comprises a display for providing an augmented reality overlay over a user's field of vision and wherein the augmented reality system is arranged and adapted. -9 -

The system may be arranged to determine the user's current position.

The system may be arranged to determine a safe or otherwise optimum path from the user's current location to a desired destination.

The system may be arranged to determine if there are any hazards or unmapped areas in the vicinity of the user's current location.

The system may be arranged to provide an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user and wherein the augmented reality overlay also comprises a series of transverse bars, images or visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination.

The system may be arranged to provide a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or unmapped area.

The system may be arranged to vary one or more visual aspects of the transverse bars, images or visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars, images or visual cues towards the desired destination.

According to another aspect there is provided a method of assisting a user who experiences freezing of gait comprising displaying an augmented reality overlay over a user's field of vision.

The method preferably further comprises determining the user's current position. The method may comprise determining a safe or otherwise optimum path from the user's current location to a desired destination.

The method may comprise determining if there are any hazards or unmapped areas in the vicinity of the user's current location.

The method may comprise providing an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user and wherein the augmented reality overlay also comprises a series of transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination.

The method may comprise providing a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or unmapped area.

The method may comprise varying one or more visual aspects of the transverse bars, images or other visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars or other images towards the desired destination.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments will now be described, by way of example only, and with reference to the accompanying drawing in which: Fig. 1 shows a flow chart illustrating a preferred embodiment of the present invention.

DETAILED DESCRIPTION

It is known that people suffering from Parkinson's disease and people suffering from dementia suffer freezing of gait ("FOG"). As discussed above it is known to provide external physical cues to a person suffering with Parkinson's disease in the form of physical coloured stripes placed on the floor in front of the person in order to assist them to overcome freezing of gait and to walk forwards.

The present inventors have experimented with such techniques and have also found that such techniques are of assistance in helping sufferers with dementia. Dementia causes plaque build-up on the brain and consequently stops certain brain receptors receiving or transmitting the correct signals.

A test was performed on a patient suffering from dementia wherein brightly coloured TRX training bands (red, blue, green, black and yellow) were placed on the floor and the patient suffering from dementia and freezing of gait was able to stride across the coloured lines with ease. It is believed that by re-routing signals in the brain of the patient using simple coloured lines or patterns on the floor and surfaces around the patient that it is possible to direct attention to the visual cues thus making the patient step to the line. The process is then repeated in the second step thereby promoting a rhythmic movement which in itself acts as a cueing system in the brain allowing the patient to continue stepping across all the lines set on the course.

It is believed that the process of stepping on to the physical lines acts as guide activating a different (visual) loop in the brain allowing the person to walk as opposed to the brain freezing when messages are mentally thought about when walking.

After more testing it was found that by using a set of transverse lines in a combination of colours rather than in a set colour worked best for patients suffering from dementia.

The present inventors have developed the known approach of providing visual cues using physical stripes positioned on the floor in front of a person by utilising a mixed reality or augmented reality environment wherein a user wears an augmented reality headset, glasses or other display apparatus and wherein a series of transverse bars, images or other visual cues are provided as an augmented reality overlay across the user's field of vision.

According to embodiments of the present invention an augmented reality system is provided which utilises an augmented reality headset or other display apparatus and which eliminates the need for the use of physical lines or stripes on the floor. The approach according to the preferred embodiment has a number of advantages over the conventional approach with the result that the person is afforded a significantly greater degree of freedom in everyday life situations.

It will be apparent, therefore, that the present invention represents a significant advance in the art.

An initial prototype was created using the game platform Unity (RTM) in combination with a Microsoft HoloLens (RTM) headset as an augmented reality display 20 device.

An augmented reality or mixed reality headset is a device which permits a person to engage with digital content and interact with digitally superimposed images which are overlaid upon a user's field of view. The technology may comprise an essentially transparent TFT stereoscopic screen that provides different images to each eye. The headsets may have an array of sensors which sense aspects of the real world using, for example, cameras and/or ultrasonic sensors. The headset preferably includes eye tracking functionality and one or more external cameras. According to the preferred embodiment the user wears an augmented reality display device which enables the user to see both real world images which are augmented or enhanced with digitally overlaid visual images.

The initial prototype utilised the same colour patterns as were first discovered by the present inventors. The augmented reality system was able to mimic the sequence of physical stripes nearly exactly in both colour and form.

The present inventors then developed the augmented reality system so as to provide substantially improved functionality compared to the conventional approach.

According to various embodiments the user or patient sees a visually strong procession of transverse or substantially horizontal lines which are preferably augmented and set solidly into a 3D space as if they were actually there on the floor in front of the user. The initial prototype delivered the ability to change the direction of the lines when the person changed position by the use of a clicker or other user interface which was connected wirelessly to the HoloLens (RTM) headset. The clicker feature reset the position point of the lines thereby allowing the user to be able to navigate corners more easily.

Various parameters could be changed including the line colour between, for example, solid white or mixed colour. The line thickness and/or spacing of the transverse or horizontal bars which were displayed could also be controlled.

Various features of the preferred system will now be discussed in more detail below and include additional features such as audible cues (for example, like a metronome), a step counter feature and a user interface ("UI") which enables the user or an assistant to implement different line widths and line lengths etc. The preferred system may also be arranged to include a dotted line feature which may, for example, indicate the outline of various features to a user or patient along with a footsteps feature which may act as a visual cue. Special effects may be incorporated into the implementation of the step counter functionality. Analytics tools may be provided for investigation and measurement.

The augmented reality system may also include or incorporate one or more gamification features such as rewards, icons or visual and/or audible encouragements as a user makes progress and gains confidence using the system. Gamification is an important aspect of the preferred system and it has been found that introducing such features encourages users to interact with the system. Such features also enable the engagement of a user with the preferred system to be measured in a simple and readily understandable manner (i.e. patient Xis a level 2 user whereas patient Y is a level 3 user) whilst at the same time positively impacting the mobility of the user.

For example, the augmented reality system may display a points total or progress indicator. As a user progresses walking over or towards the one or more of the transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user, the augmented reality system may display an updated or increased points total or progress indicator.

Similarly, the augmented reality system may award the user with additional points or other indication of progress as the user walks over or towards the one or more transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user.

The augmented reality system may also be arranged and adapted to display one or more reward icons or pop-up images and/or provide other sensory feedback after the user has progressed walking over or towards the one or more of the transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user.

According to various embodiments the reward icons or pop-up images and/or the provision of other sensory feedback may only be provided to the user after the user has made some initial progress. It is contemplated, for example, that no reward icons or pop-up images are initially provided to a user whilst the user crosses the first few transverse bars, images or other visual cues. However, after the user has made some initial progress they may then be rewarded with one or more reward icons or pop-up images and/or the provision of other sensory feedback.

Features such as: (i) the display of a points total or progress indicator; 00 the awarding of additional points or other indicators of progress; and (iii) the display of one or more reward icons or pop-up images and/or the provision of other sensory feedback after the user has progressed walking helps to provide the user with an enhanced gamified experience.

According to various embodiments of the present invention the user is encouraged to enjoy the experience of walking forward in an analogous manner to playing a game and may be rewarded with visual, audible and other sensory feedback or stimuli as the user progresses walking forwards towards a desired destination. The other sensory feedback which may be provided may include audible and/or tactile feedback. For example, the display of one or more reward icons or pop-up images may be accompanied with a sound or chime. The augmented reality system may alternatively or additionally provide feedback to the user by, for example, causing a controller or other device to vibrate.

Various embodiments are contemplated wherein the user experience may include various gamification aspects. For example, the user may struggle with motivation to use the augmented reality headset to assist them with navigating from their current position to a desired destination. According to various embodiments the user may experience a gamified experience to help with engagement. Visual and/or audible rewards may be provided or unlocked over a longer period of time as the user continues to make progress.

As discussed in more detail below, the system may also include functionality which enables remote setup for patients or users.

Other features of the preferred system which will also be discussed in more detail below include the use of a medical database and headset data capture which is secured or otherwise archived against or using a distributed ledger such as blockchain. The data which is stored using blockchain may be made accessible to researchers and other practitioners around the world.

In addition to assisting a user or patient to walk towards a desired destination, the system according to various embodiments may also include features which enable the tracking of the user's hands and the tracking of objects such as a cup or glass. The system may facilitate a combined experience wherein two or more headsets (i.e. two or more users) may interact for combined collaboration or an interactive experience.

The system may be arranged to interact with other objects such as a walking stick or other walking aid. The walking stick or other walking aid may include a clicker or other user control device such that the walking stick or other walking aid is connected to the experience and operates as part of the overall augmented reality system.

The system may be arranged to recognise one or more magic symbols for tracking and analytics and other measurements may be made in order to understand how patients walk and to amend various settings of the system.

An augmented reality system according to various preferred embodiments which is arranged and adapted to assist a user who experiences freezing of gait will now be described in more detail with reference to Fig. 1. The user who suffers from freezing of gait may suffer from Parkinson's disease, from the onset of dementia or from another condition.

The augmented reality system preferably comprises a display for providing an augmented reality overlay over a user's field of vision.

According to the preferred embodiment the augmented reality system is preferably arranged and adapted to determine 101 the user's current position. For example, the user's current position may be determined by a global positioning system ("GPS"), a Wi-Fi Positioning System ("WPS"), a geographic information system ("GIS") or other geospatial locating means. According to another embodiment the user's current position on a map or layout may also be set or determined by the user or by a nurse, assistant or practitioner.

The user, patient or an assistant, nurse or practitioner may also use audible commands to set the location of the user. For example, the user or an assistant, nurse or practitioner may verbally tell or otherwise inform the augmented reality system that the user is starting from a certain location e.g. the lounge or sitting room.

The user, patient or an assistant, nurse or practitioner may then indicate or input to the system a desired location. For example, it may be desired that the user or patient navigates from the lounge or sitting room to the kitchen. The desired location or destination may be set on a map or layout. The user or an assistant, nurse or practitioner may also use audible commands to set the desired destination of the user or patient. For example, the user or an assistant, nurse or practitioner may verbally tell the augmented reality system that the user wishes to navigate to a certain location e.g. the kitchen. Once the user's current position and desired destination have been determined, according to various embodiments the system may then be arranged to determine 102 a safe or otherwise optimum path from the user's current location (e.g. lounge or sitting room) to the desired destination (e.g. kitchen).

According to various preferred embodiments the system may be arranged to determine 103 if there are any hazards or unmapped areas in the vicinity of the user's current location. It may be, for example, that there are one or more hazards to be avoided between the user's current location and the desired destination. For example, it may be desired to avoid internal steps or stairs, low ceilings, potential trip hazards, potentially slippery surfaces, water hazards, areas with sharp edges or areas with poor or no lighting.

The user or patient may also be located in a location which is unfamiliar or relatively unfamiliar to the user such a house, hospital or other facility which they may be visiting for the first time or which they have not visited for a long time. Accordingly, there may be unmapped areas in the vicinity of the user's current location.

The system is preferably arranged to provide 104 to the user's headset, glasses or other display apparatus an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user.

The system is preferably arranged to provide an augmented reality overlay which comprises a series of transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination.

The series of transverse bars, images or other visual cues may be displayed in primary colours. It has been found, for example, to be particularly effective to display the series of transverse or horizontal bars, images or other visual cues in primary colours that alternate red, green, blue and yellow. Various embodiments are contemplated wherein the series of transverse bars, images or other visual cues may be customised for the user optionally based upon other user data and/or after a process of trial and error. The colour and/or sequence of colours used to display the transverse bars, images or other visual cues may in particular be customised. For example, a first user may find that a sequence of colours red, green, blue then yellow is particularly effective whereas a second user may find that a different sequence of colours namely red, green, blue, green, yellow, green is particularly effective. A third user may find that a yet further different sequence of colours red, red, green, green, blue, blue, yellow, yellow is particularly effective. Other embodiments are also contemplated wherein non-primary colours and colours such as white, grey and black may be used.

According to various embodiments the width and/or thickness of the transverse or horizontal bars, images or other visual cues may be arranged to vary, increase or decrease with distance from the user. For example, the width of the transverse bars, images or other visual cues may be arranged to progressively increase or decrease with distance away from the current position of the user. Similarly, the thickness of the transverse bars, images or other visual cues may be arranged to progressively increase or decrease with distance away from the current position of the user.

It is contemplated that a user may have a user profile which includes personalised settings. Aspects such as preferred colours, preferred colour sequence, preferred line width, preferred line thickness may be set or determined in advance and may be stored as a user profile.

The system may also learn and seek to optimise various parameters during use.

For example, the system may experiment with different colours, different colour sequences, different line widths and/or different line thicknesses and see what settings are optimal for a particular user. If the system determines that a user should be moving but no movement is detected, then the system may try different parameters and different combinations of parameters in order to see whether certain settings elicit a positive response from the user.

For example, the system may display the series of transverse bars, images or other visual cues using default settings but may see whether changes to the default settings are more effective for a particular user. The system may, for example, initially display the series of transverse bars, images or other visual cues using a default colour sequence of red, green, blue then yellow. However, the system may then experiment and see whether a different sequence of colours red, green, blue, green, yellow, green elicits an improved response from the user. Similarly, the system may then further test whether another different sequence of colours such as red, red, green, green, blue, blue, yellow, yellow elicits a yet further improved response from the user.

The series of transverse bars, images or other visual cues may be provided in combination with one or more audio or audible cues or one or more sound effects. For example, the user may be of advanced age and hence may have reduced eyesight. Accordingly, the user may lack confidence to a certain degree in respect of the visual cues which they are provided with. The provision of audio or audible cues may give the user greater or additional confidence to step onto the transverse bars, images or other visual cues. According to an embodiment the audio or audible cues may comprise a metronome.

The timing of the metronome may be customised to match the gait or walking speed of the user.

A step counter may be incorporated to help an assistant or nurse know how far the user or patient had gone or travelled. For example, the user may be motivated to perform a certain amount of steps over a certain period of time (one day) and the step counter may be linked to other devices such as a Titbit (RTM) or other personal fitness device in order to feedback to the user the total number of steps that they have taken over a certain period.

According to other embodiments a user or patient who utilises the system and begins to make progress may be rewarded with various badges and achievement rewards as part of a gamified experience. Providing a gamified experience allows the user or patient to be rewarded with (virtual) badges or (virtual) achievement rewards which can help to provide motivation to the user or patient. The (virtual) badges or (virtual) achievement rewards may also be used to help set targets and create a desire to spend more time utilising the system in order to collect more (virtual) badges or (virtual) achievement rewards.

A nurse, assistant or practitioner may be provided with an overall data analytics tool which includes a dashboard which enables the nurse, assistant or practitioner to look at different users or patients and to monitor their time spent, work done, targets met and badges achieved or rewarded. The data may be shared with other nurses, assistant, practitioners or more generally other health care professionals subject to data privacy considerations. The data may be reported to government agencies or insurance companies in a manner in compliance with data privacy laws.

A nurse, assistant or practitioner may also interact with the system to check whether a user or patient has performed or undertaken one or more tasks which may have been set for them by the nurse, assistant or practitioner. According to an embodiment a nurse, assistant or practitioner may access the dashboard (either directly or remotely) to look at user or patient data. For example, the nurse, assistant or practitioner is able to look at a particular user's or patient's details or data in order to determine the time spent by the user or patient, work done, targets met and badges or other achievement awards awarded.

Anonymised data may also be made available to researchers in a confidential manner. For example, researchers often have difficulty gaining access to or comparing large data sets of relevant data. According to various embodiments approved researchers may be allowed access to anonymised patient data and results. Researchers may, for example, be able to make assessments as to how the system should be optimised for different medical conditions and how the augmented reality display which is viewed by the user or patient may be customised or vary as, for example, a medical condition progresses, worsens or indeed improves with intervention. Embodiments are contemplated wherein gamification features may be utilised for mild sufferers of a condition, but as a condition progresses then gamification features such as badges and achievement rewards may be simplified or ultimately omitted entirely so that a user's or patient's focus is directed entirely onto following the series of transverse bars, images or other visual cues which are provided to the user.

The system may be arranged to provide data analysis for researchers and other practitioners. Researchers may have difficulty knowing how to understand the data from augmented reality system and associated software. A user-friendly dashboard is preferably provided which includes various reporting functions to allow searching by age range, the severity of the problem, colourways used and other data fields. The reporting system allows both very specific reports to be generated (e.g. restricted to users having an age 65-70 years) and also broadly defined reports to be generated (e.g. users who had greater success with primary coloured lines or other specific colourways).

The system may include functionality which helps a nurse, assistant or practitioner to know when their patient is getting better at performing tasks such as walking with time and if necessary amending various settings of the system which may result in the patient improving. The system may include analytics and make measurements as to how a user or patient walks and amend various settings accordingly. The system may collect and/or monitor data such as the user's or patient's gait, speed, stride length or distance covered.

The data which is collected and/or monitored may allow a nurse, assistant or practitioner to amend the settings accordingly.

Nurses, assistants or practitioners may also be able to access data and compare large data sets of relevant data. For example, nurses, assistant or practitioners may be enabled to access details relating to their own users or patients and compare the progress of their own users or patients against anonymised data sets relating to a larger pool of users who are not necessarily other users or patients of the nurse, assistant or practitioner.

The system preferably provides 105 a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or 30 unmapped area.

Embodiments are also contemplated wherein the user or patient may be able to direct where the transverse bars, images or other visual cues appear in front of them. A user or patient may use a handheld device or clicker and point the handheld device or clicker in the direction where they wish to move. The system may be arranged to visually overlay transverse bars, images or other visual cues in the direction that the user or patient wishes to move even if the route that the user or patient wishes to take is not the optimum path (i.e. shortest path). However, the system may override the wishes of the user or patient if the system determines that there are one or more hazards in the vicinity of where the user wishes to move. Once the user or patient has moved or turned, the user or patient may then point and click the handheld device or clicker again and the system may visually overlay a new set of transverse bars, images or other visual cues in the new direction that the user or patient wishes to move in.

The system may visually overlay sets of transverse bars, images or other visual cues in a direction or along a path which is determined to avoid one or more hazards or other potential distractions.

The system according to various preferred embodiments may interact with a distributed geospatial data gathering or positioning system. Geospatial data relating to the interior spaces of buildings may be developed and accessed by the system. According to an embodiment a blockchain based database of geospatial data points relating to the internal or interior spaces of buildings (such as hospitals, doctor surgeries, care homes, nursing homes etc.) other public spaces (such as airports, stations, bus stations, parks etc.) and commercial premises (such as supermarkets, pubs, cafes, restaurants etc.) may be generated. The blockchain based database may be made available to developers in return for an access fee which may be distributed to users who initially collected the geospatial data which is accessed by the developer. The transactional nature of the blockchain based database makes it easy to track who created the geospatial data and who is consuming the geospatial data in order to streamline the transactional process.

It is recognised that users, patients and practitioners initially may find it difficult to learn how to walk or move with an augmented reality headset or other mixed reality system or headset. Accordingly, the system and the augmented reality headset, glasses or other user wearable device may be loaded with or may access tutorials which may be customised for different potential user groups. The tutorials, other how-to information and general troubleshooting information may be accessible on the paired augmented reality headset, glasses or other user wearable device. Both IOS and Android may be supported along with other operating systems.

An important aspect of the preferred system is preferred pathfinding functionality.

Vulnerable patients or users need to be able to define which route they need to take to a desired destination. For example, a user or patient may need assistance in determining an appropriate path from e.g. the living room to the kitchen or vice versa. The pathfinding functionality may be utilised in respect of a user's or patient's residence (e.g. private home or a care home) and may be created by a nurse, assistant or practitioner. According to an embodiment a user or patient may request a path by clicking through way points or voice commands. The system preferably recognises the location where the user or patient is located and a series of transverse bars, images or other visual cues are preferably superimposed upon the users or patient's field of view in order to guide the user or patient without it being necessary for the user or patient to state their current starting location.

A nurse, assistant or practitioner may be enabled to set up one or more routes or pathways around a particular location, residence or facility. The system according to various embodiments preferably provides a functionality wherein a nurse, assistant or practitioner can walk around a location and manually set waypoints. The waypoints may indicate a safe or optimum route which a user or patient may wish to follow. The system may then automatically create various optimum or safe pathways between the set waypoints. Equally, the nurse, assistant or practitioner may be enabled to manually indicate one or more locations of potential hazards such as stairs, internal steps or low lying potential trip hazards. The system may accordingly generate optimum or safe pathways which seek to avoid such indicated potential hazards. According to an embodiment a nurse, assistant or practitioner may walk around a location using a handheld device or clicker and set or drop a number of waypoints such as preferred access points to specific rooms or locations such as a bathroom or living room. Paths or preferred routes between the waypoints may be defined and either certain areas or indeed the whole of an area, room or home may be mapped with safe or optimum pathways. Essentially, each way point may comprise a node of a map of nodes and associated preferred interconnections between the nodes.

According to various embodiments waypoints for super localised location of data within buildings may be provided which are linked with geospatial data.

The system preferably includes a spatial data sharing function so that multiple devices can be set up at the same time. In particular, pathways and preferred mapping may be shareable across multiple device. It is contemplated, for example, that a facility such as a hospital, treatment centre, care home or rest home may make multiple augmented reality headsets, glasses or other wearable device available to users or patients. The pathways and other geospatial data which may have been initially created for one specific user or patient may be shared more widely within the system so that other users or patients can access the same pathways and geospatial data. The geospatial data may be recorded using a distributed ledger such as blockchain and the system can determine who is accessing the data whilst making sure that the data is only made available to approved devices and practitioners.

The system may include an ID verification routine optionally using biometric data so that a user or patient is uniquely identified before an augmented reality visual overlay is provided to the user or patient. The user or patient may, for example, be identified by iris recognition, facial recognition or fingerprint recognition. Pathways and maps stored in the -21 -blockchain may only be made available to authorised users who optionally have passed an ID verification routine.

The system may include a room detection functionality since the user or patient may not be certain in which room or at which location the user or patient is starting from. In particular, vulnerable patients may need additional support in order to recognise where they are. A user or patient may use a handheld device or clicker or a voice command to find out which room or location they are in. The user or patient may similarly use the handheld device or clicker or a voice command to request a pathway to an intended or desired destination. According to various embodiments the device may recognise where the user or patient is located and the user is preferably enabled to ask or click for a pathway to a certain location such as the kitchen without needing to state their current or starting location.

It will be understood that a user or patient may be concerned about falling or going in the wrong direction. The system may include a confidence level feature in respect of unmapped areas. In particular, the system is preferably arranged to determine areas which have been mapped and areas which have not been mapped or which may only have been partially mapped. A confidence level can then be provided by the system. Accordingly, a pathway which is set for a highly vulnerable patient may be set which has only the highest possible level of confidence. Equally, if the user or patient is not particularly vulnerable or is only suffering from a mild condition, then the system may set a pathway for the user or patient which has a lower confidence level. For example, the system may have a high level of confidence that a particular pathway does not include a significant potential hazard such as stairs or internal steps but the system may have a lower level of confidence that a particular pathway does not include one or more movable trip hazards such as a low level coffee table or the like.

The system may indicate or represent to the user or patient certain directions or pathways which should be avoided or which the user or patient should not follow.

One advantage of accessing geospatial data which is stored in a distributed ledger such as blockchain is that one particular user or patient may benefit from up-to-date geospatial data which may have been provided or updated by another user, patient or their associated nurse, assistant or practitioner. For example, a nurse, assistant or practitioner may have updated a geospatial map of a certain location to indicate a new potential hazard such as a new piece of furniture which may have been installed very recently. Accordingly, users or patients may install updated maps and/or updated data each time they use the augmented reality system.

The augmented reality system may include an emergency call out feature. According to various embodiments if a user or patient falls or otherwise finds themselves in -22 -distress whilst using the augmented reality system whilst unaccompanied, the user can trigger an emergency call out. The user or patient may communicate to an emergency contact that they need help and this may be via an alarm on a paired device. Accordingly, in a moment of distress a user or patient can use a voice command to alert a carer that they are in need of urgent assistance.

The augmented reality system may include a remote setup function for patients. The remote setup function allows a nurse, assistant or practitioner to be able to set up the device for the patient in advance which leads to a quicker process in using the system. Furthermore, a nurse, assistant or practitioner is given first-hand experience of using the device so that they can see what the user or patient will see or experience. The nurse, assistant or practitioner when viewing what a user or patient will see or experience can then customise the experience for the user or patient. This is particularly useful when multiple devices are being used in one facility. For example, a facility may stock a plurality of different models of augmented reality headset or glasses which may have slightly different physical or visual characteristics. Accordingly, a nurse, assistant or practitioner may adjust various parameters of the augmented reality experience dependent upon the model of headset or glasses which the user or patient is to use. According to an embodiment a nurse, assistant or practitioner may be enabled to check the visual set-up of the headset. It has been found, during testing for example, that the view which is provided by the system may be set specific to a particular user or patient. A person setting up the system may be inclined to look more forward than down but this perspective may different to the preferred visual orientation of the user or patient. Remote set up may be performed by enabling a sharing of headsets and headset views. A phone remote control system APP may be linked between the headset and the patient device via WiFi. Alternatively, a separate headset may be linked to the same networked experience.

The system may be arranged and adapted to track the movement of the user's or patient's hands and/or fingers. In particular, the system may be arranged and adapted to track the movement of the user's or patient's hands and/or fingers in order to determine the rhythm of walking. The same function may also be applied to other parts of the body. For example, the system may track the movement of the arm or other parts of the upper body in order to monitor whether or not the user or patient reaches one or more physiotherapy goals which may have been set for them.

The system may also be arranged to provide an augmented visual overlay which colours various objects around them. For example, the floor or carpet on which a user walks may be coloured in a muted colour so as to minimise potential distraction and to standardise the appearance of the series of transverse bars, images or other visual cues which are preferably displayed over the user's or patient's field of view. Objects which are observed may be recognised using artificial intelligence or machine learning. Objects which have been recognised can be coloured, painted or otherwise rendered in a standard or user specific manner in the geospatial space. As discussed above, the system may be arranged to provide an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user or patient. It has been found that colouring certain objects using an augmented reality visual overlay can help to better coordinate motor responses of users or patients.

According to various embodiments, door handles or other objects which the user may need to touch or operate can be rendered by the augmented reality system in a standard colour e.g. red in order to highlight to the user or patient where they need to touch or operate. In addition, according to various embodiments an icon and/or moving graphic image may be displayed adjacent an item such as a door handle indicating the type of movement which is needed to open the door. For example, with a sliding door an arrow (which may be animated) may be displayed indicating the direction that the door needs to be slid in order to open or close the door. As another example, a symbol or animated graphic may be displayed next to a door handle or door knob indicating the direction that the door handle or door knob needs to be turned in order to open or close the door.

In addition to an augmented reality headset or glasses, the user or patient may also be provided with a walking aid such as a walking stick or walking frame. The walking stick or walking frame may incorporate a clicker or other means of registering an input into the system. For example, a user or patient can use a walking stick which includes a clicker within the handle. The user or patient may press the clicker to indicate that they wish to move to a desired destination and/or to change one or more settings of the system. In particular, the user or patient can interact with the augmented reality system using the clicker or other control switch provided in the walking stick, walking frame or other walking aid. Some patients are more relaxed and confident when walking with the aid of a walking stick or other walking aid. In particular, walking with a walking stick or other walking aid can give the user or patient a sense of independence in that they are less dependent upon being supported by a nurse, assistant or carer all the time.

The system may allow the user or patient to identify objects in their field of vision by virtue of detecting a magic symbol or code. For example, according to an embodiment various labels can be printed which include a magic symbol or code. The labels may then be attached to objects such as a door or a mug. The augmented reality system may be arranged to recognise different magic symbols or codes and identify the object to the user or patient. According to an embodiment a user or patient may be given a visual and/or audible indication that they are approaching a certain object. For example, the user or patient may receive a visual and/or audible indication that they are a certain distance away from a certain object such as a door. Tasks such as raising a mug or glass to drink may be assisted by the system recognising a label attached to the mug or glass and confirming to the user or patient that the mug or glass to be used is in front of them. The use of magic symbols or codes has been found to result in a substantial increase in object recognition which is particularly beneficial to users or patients who may be suffering from Parkinson's disease or the onset of dementia.

The system may be arranged 106 to vary one or more visual aspects of the transverse bars, images or other visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars or other images towards the desired destination.

As discussed above, the incorporation of such features has been found to be particularly advantageous in terms of assisting a user to initiate and continue walking.

Although the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as set forth in the accompanying claims.

Claims

Claims 1. An augmented reality system for assisting a user who experiences freezing of gait, wherein the augmented reality system comprises a display for providing an augmented reality overlay over a user's field of vision and wherein the augmented reality system is arranged and adapted: (i) to determine the user's current position; (ii) to determine a safe or otherwise optimum path from the user's current location to a desired destination; (iii) to determine if there are any hazards or unmapped areas in the vicinity of the user's current location; (iv) to provide an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user and wherein the augmented reality overlay also comprises a series of transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination; (v) to provide a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or unmapped area; and (vi) to vary one or more visual aspects of the transverse bars, images or other visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars or other images towards the desired destination.
2. An augmented reality system as claimed in claim 1, wherein the augmented reality display comprises a headset or glasses.
3. An augmented reality system as claimed in claim 1 or 2, wherein the augmented reality system is arranged and adapted to set the distance between the transverse bars, images or visual cues either: (i) in proportion to the user's height; (ii) in proportion to the user's average gait; or (iii) in response to a user specific setting.
4. An augmented reality system as claimed in claim 1, 2 or 3, wherein the augmented reality system is arranged and adapted to reset the position and/or direction of travel of the transverse bars, images or other visual cues in order to encourage or assist the user to change direction or turn a corner.
5. An augmented reality system as claimed in any preceding claim, wherein the augmented reality system is arranged and adapted to set the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues at a first setting in order to encourage or assist the user to initiate walking forwards following the series of transverse bars, images or visual cues.
6. An augmented reality system as claimed in claim 5, wherein the augmented reality system is arranged and adapted to vary the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues at a second different setting once a user has commenced walking forwards following the series of transverse bars, images or visual cues.
7. An augmented reality system as claimed in any preceding claim, wherein the augmented reality system is arranged and adapted to monitor the progress of the user and to vary the colour and/or intensity and/or spacing and/or width of the transverse bars, images or visual cues in the event that the augmented reality system determines that the user is struggling or faltering to walk forwards following the series of transverse bars, images or visual cues.
8. An augmented reality system as claimed in any preceding claim, wherein the augmented reality system is arranged and adapted to monitor the progress of the user and to test different colours and/or intensities and/or spacings and/or widths of the transverse bars, images or visual cues in order to determine optimum user specific colours and/or intensities and/or spacings and/or widths of the transverse bars, images or visual cues which have the effect of encouraging or assisting the user to walk forwards following the series of transverse bars, images or visual cues in an optimum manner.
9. An augmented reality system as claimed in any preceding claim, wherein the augmented reality system is arranged and adapted to generate one or more audible cues.
10. An augmented reality system as claimed in claim 9, wherein the one or more audible cues comprise one or more sounds or noise triggers as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars, images or other visual cues.
11. An augmented reality system as claimed in any preceding claim, wherein the augmented reality system is arranged and adapted to display a points total or progress indicator, wherein as a user progresses walking over or towards the one or more of the transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user, the augmented reality system displays an updated or increased points total or progress indicator.
12. An augmented reality system as claimed in claim 11, wherein the augmented reality system is arranged and adapted to award the user with additional points or other indication of progress as the user walks over or towards the one or more transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user.
13. An augmented reality system as claimed in any preceding claim, wherein the augmented reality system is arranged and adapted to display one or more reward icons, pop-up images and/or provide other sensory feedback after the user has progressed walking over or towards the one or more of the transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user.
14. A method of assisting a user who experiences freezing of gait comprising displaying an augmented reality overlay over a user's field of vision, wherein the method further comprises: (i) determining the user's current position; (ii) determining a safe or otherwise optimum path from the user's current location to a desired destination; (iii) determining if there are any hazards or unmapped areas in the vicinity of the user's current location; (iv) providing an augmented reality overlay which visually masks or at least partially obscures any hazards or unmapped areas which might distract, attract or confuse the user and wherein the augmented reality overlay also comprises a series of transverse bars, images or other visual cues which appear to the user to be located on the ground in front of the user and which act to prompt the user to step forwards and follow the determined safe or otherwise optimum path from the user's current location to the desired destination; (v) providing a sensory warning to the user should the user deviate from the determined safe or otherwise optimum path and approach a hazard or unmapped area; and (vi) varying one or more visual aspects of the transverse bars, images or other visual cues which appear to the user as the user progresses in order to encourage or assist the user to continue walking forwards following the series of transverse bars or other images towards the desired destination.