WO2012087116A1

WO2012087116A1 - Method and interactive movement device for moving an avatar on a track

Info

Publication number: WO2012087116A1
Application number: PCT/NL2011/050744
Authority: WO
Inventors: Carla Thea Scholten
Original assignee: Embedded Games Holding B.V.
Priority date: 2010-11-11
Filing date: 2011-11-02
Publication date: 2012-06-28
Also published as: NL1038375C2

Abstract

The invention relates to a method, and a related movement device, and elongated sliding floor as well as a computer program product, for moving (13) an avatar (10) on a track (11) in an environment displayed on an image display unit (19), using an electronic processing unit. Said movement takes place under the influence of movements of a user (2) detected by a sensor system (6), which sensor system (6) is stationary relative to the user (2) in use. The sensor system (6) is designed for detecting movement and direction of movement. The invention is characterized in that a first movement in one direction detected by the sensor system (6) and a next, second movement substantially in the same direction detected by the sensor system is converted by means of the processing unit (7) into influencing of the movement of the avatar (10) on the track (11).

Description

Title: Method and interactive movement device for moving an avatar on a track DESCRIPTION

In practice, interactive movement devices have been developed for stimulating physical activity and for training purposes for sports people, thus following up on the electronic gaming culture.

In general, such movement devices comprise an electronic processing unit, such as a computer or a processor, and an image display unit connected thereto, on which a real or imaginary or virtual environment is displayed, in which an electronic representation of a human or an animal or other creature, hereinafter called "avatar", executes movements which to a greater or lesser extent correspond to a user's movements as detected by a sensor system. By means of such an interactive movement device the user can receive feedback, via the image display unit, regarding his or her motion performances, for example the extent of movement of the avatar on a track in a virtual bicycle race in dependence on the speed at which the pedals of an exercise bicycle are being turned, or the speed and the distance developed by a user walking or running on a treadmill, or the like. This feedback enables the user to effectively improve his or her movement technique and performance, for example.

Besides the visual feedback, a game element may for example be incorporated, wherein the user must execute various movements, such as, for example, gripping imaginary objects, dodging imaginary obstacles and the like in dependence on the environment being displayed on the image display unit. In this way it is possible, for example, to specifically stimulate or train physical activities.

Such interactive movement devices are known, for example from US patent application US 2006/0262120 and US patent application 2006/021 1462.

It has been found that this form of interactive movement adds an extra dimension to a training session both in a recreational context and for sports people, also enabling the user to measure his performance against other avatars being displayed on the image display unit.

In a number of sports it must be possible to train a specific movement of a user.

It is an object of the invention to provide a method and a movement device for interactively giving a user feedback, using an avatar, when executing a specific movement. According to a first aspect, the invention to that end provides a method for moving an avatar on a track in an environment displayed on an image display unit, using an electronic processing unit, under influence of a movement of a user detected by a sensor system , which sensor system is stationary relative to the user in use and which is arranged for detecting movement and direction of movement.

The method is characterised in that the sensor system is arranged for detecting movement substantially along a finite, imaginary straight line, and in that the sensor system comprises at least two sensors disposed spaced from each other along the imaginary straight line, which sensors have a detection field oriented transversely to the imaginary straight line for activating a respective sensor, wherein activation of a sensor is detected as movement and wherein the direction of movement is detected from a succession of activations of the sensors, such that a first movement in one direction detected by the sensor system and a next, second movement in the same direction detected by the sensor system is converted via the processing unit into a manipulation of the movement of the avatar on the track.

Using this method, a user's leg movements, such as a skating stroke or a kick scooter-riding movement, but also, for example, arm movements made during skiing or the like can be detected in such a manner that only the detection of such movement by the sensor system leads to a manipulation of the displayed movement of the avatar on the track, for example an accelerated forward movement. In the method according to the invention , the sensor system is positioned stationary with respect to the user during operation. This makes it possible to use an optical sensor, for example, such as an infrared sensor, or a combination of a photodiode and a photodetector acting as a light lock as a motion sensor, so that the user need not necessarily be fitted with sensors or sensor actuating means or the like for detecting the movement and the direction of movement. It suffices in that case for the user to make the movement in question with his limbs, such as his legs and/or arms. The invention is based on the perception that the movement of the avatar on the track as displayed on the image display unit is affected solely if the user executes a movement which corresponds, whether or not in simulated form, to a movement that a respective avatar must make in order to move on the track. In the case of an avatar in the form of a long-distance skater, this is the correct way of executing the skating movement, i.e. push-off, recovery and placement of the two legs, of which sequence of movements the actual skating movement is made up. In the present invention, incorrect execution of this movement will not lead to an effective movement of the avatar. Since the detection field of a respective sensor is oriented transversely to the imaginary straight line, a user's leg or foot movements not executed exactly along the imaginary line, for example in the case of a skating movement, will be detected as well. These variations do not affect the movement of the avatar, as long as the skating motion is in itself carried out correctly. The distance between a user and the sensor system, measured in the direction of the detection field, is not relevant to the detection of the movement in question, since the sensors' detection field is oriented transversely to the imaginary straight line. The same obtains if the movements are kick scooter-riding movements. A movement of the legs or the feet is detected in that a leg or a foot passes through the detection field of a respective sensor, causing it to be activated or, on the contrary, deactivated, for example, depending on the type of sensor. The direction of movement is detected on the basis of the sequence in which the various sensors are activated or deactivated. In another embodiment of the method according to the invention, in which the avatar is moved at a certain speed on the track, the speed of movement of the avatar is affected by means of the processing unit in dependence on a measured period of time between the first movement and the second movement detected by the sensor system. For example the time between push-off and recovery during a skating movement.

The speed of the avatar is directly related to the user's speed of movement, so that the user is given realistic feedback, through the avatar's speed, of his motion effort, i.e. the correctness of the movement and the user's motion performance or energy.

A skating movement, for example, is detected by the sensor system by means of a first movement, for example the user pushing off with a first leg in a direction across the imaginary straight line, and a second movement in which the second leg is pulled in in the same direction as the first leg. The time that elapses between the detection of the first and the second movement is a measure of the speed of movement of the avatar on the track.

In particular for use in a skating movement of skating stroke of a long-distance skater, the invention further provides for the avatar's speed of movement being affected by means of the processing unit in dependence on a measured period of time between a second movement in a first direction and a first movement in a second direction different from the first direction as detected by the sensor system. That is, the time between recovery and renewed push-off.

In yet another embodiment of the invention, the speed of movement of the avatar is influenced by means of the processing unit in dependence on a measured period of time between a second movement in a first direction and a second movement in a second direction different from the first direction as detected by the sensor system. In skating terms, the time between two successive pull-ins in different directions of movement. It will be understood that also the spacing between the sensors, measured along the imaginary straight line, is relevant in the calculation of the speed. In an embodiment in which the sensor system comprises more than two sensors disposed spaced from each other along the imaginary straight line, it is possible, for example in the case of a skating stroke, to determine the distance over which the skating stroke is to be executed in advance by selecting a respective pair of spaced-apart sensors. If desired, the sensor system may also be a system which is capable of detecting motion along part of the imaginary straight line or along the entire imaginary straight line.

The invention further provides that, based on the measured times, the speed of movement of the avatar is affected by means of the processing unit in dependence on a measured frequency with which the various movements in the first and the second direction succeed one another. That is, the movement of the avatar partially depends on the frequency of movement.

To practice long-distance skating, use is often made of a sliding floor in the form of a smooth, elongated board, over which the user moves to and from in longitudinal direction substantially along an imaginary straight line with both legs for practising the skating movement. The sensor system is disposed to detect first and second movements substantially along a finite, imaginary straight line, which imaginary straight line extends in the longitudinal direction of the sliding floor and which is bounded by the ends of the elongated sliding floor, in the longitudinal direction thereof.

The sensors and their respective detection fields are preferably arranged along the finite, imaginary straight line, spaced from each of the ends thereof, so that easy detection of movement past a respective sensor in the direction of an end of the imaginary straight line is possible. Such is the case with a skating stroke, for example, in which the user's legs or feet are moved along and past a respective sensor.

In yet another embodiment of the method according to the invention, the sensor system comprises a sensor disposed spaced from the imaginary straight line, near the centre thereof, with a detection field for activating a sensor oriented substantially transversely to the imaginary straight line, in which the activation of the sensor is detected as movement, and a further sensor disposed near each end of the imaginary straight line, wherein the direction of movement is detected from the activation of a respective further sensor.

The further sensor disposed at each end of the imaginary straight line may be a pressure sensor or force sensor, for example, which detects the exertion of a pressure or a force exerted thereon by a limb, for example a foot. Such an embodiment constitutes a very user-friendly application, without any impediment for the user in the form of needing to wear or hold sensors or the like. In practice this solution is advantageous also from the viewpoint of cost.

Detection, in yet another embodiment of the invention, by means of the sensor system and the processing unit of a distance covered by the user along the imaginary straight line between a first and a second movement, makes it possible to manipulate the movement of the avatar on the track on the basis of the deflection in the movement, for example a skating stroke. A greater deflection, for example at the same speed of movement, can thus lead to a higher speed of movement of the avatar.

According to the invention, the deflection in the movement along the imaginary straight line can furthermore be limited by using movable or removable stop blocks. Using such stop blocks, it is possible to set the deflection in the movement, such as the length of a skating stroke.

The invention advantageously provides that the extent to which the movement of the avatar on the track is influenced can be set for various operating modes by means of the processing unit. That is, the movement of the avatar can be geared to the practice conditions, such as the skid resistance of the sliding floor, the type of movement that must be trained, head wind and the like, so as to give the user the most realistic feedback possible by means of the avatar. In the embodiment that comprises several sensors disposed spaced from each other along the sliding floor, with a detection field oriented transversely to the sliding floor, the length of a skating stroke to be made can be determined by selecting a respective pair of sensors spaced a desired distance apart. The invention further provides a sliding floor which slopes slightly upwards at the ends, seen in longitudinal direction, for example so as to introduce a further force effect into the practice session.

According to the invention, the sensor system comprises yet further sensors for detecting movements of the user, which movements are converted, via the processing unit, into corresponding movements of the avatar. This makes it possible to incorporate the aforesaid elements, such as gripping objects, dodging obstacles, ducking by a user from an upright position and the like, into the practice session, also in order to provide interactive gaming features.

In an embodiment of the method according to invention, inter alia for training purposes, the sensor system comprises yet further sensors for detecting the user's physiological condition, wherein the manipulation of the movement of the avatar on the track is partially affected, via the processing unit, by the detected physiological condition of the user.

The physiological condition of the user can for example be represented from the measurement of the heartbeat, the temperature, the humidity of the skin, the breathing frequency, etc. The user's freedom of movement is impeded as little as possible in that use is made of a wireless sensor system.

According to a second aspect, the invention also provides an interactive movement device, comprising an electronic processing unit, an image display unit connected to the electronic processing unit and a sensor system arranged for detecting a user's movement and direction of movement, which electronic processing unit is designed for moving and avatar on a track in an environment displayed on the image display unit under influence of a movement of the user detected by the sensor system, which sensor system, during use, is positioned stationary with respect to the user, characterised in that the sensor system is arranged for detecting movement taking place substantially along a finite, imaginary straight line, and in that the sensor system comprises at least two sensors disposed spaced from each other along the imaginary straight line, with a detection field oriented transversely to the imaginary straight line for activating a respective sensor, wherein activation of a sensor is detected as movement and wherein the direction of movement is detected from a succession of activations of the sensors, wherein the processing unit is further arranged for converting a first movement in one direction and a next, second movement in the same direction detected by the sensor system as detected by the sensor system into a manipulation of the movement of the avatar on the track.

In one embodiment, the interactive movement device comprises an elongated sliding floor, wherein the sensor system is arranged for detecting first and second movements substantially along a finite, imaginary straight line in the longitudinal direction of the sliding floor. Such an interactive movement device is in particular suitable for practising a skating movement or skating stroke. Although the sensors can be provided as separate components with the sliding floor, the invention further provides that the at least two sensors are fixedly connected to the elongated sliding floor, and that the sliding floor is further provided near each end thereof with movable (in the longitudinal direction of the sliding floor) or removable stop blocks. Using the stop blocks, it is possible to set the deflection of the movement, i.e. the skating stroke. By positioning one or more force sensors on or near the stop blocks, it is also possible to detect and measure the push-off force of the skating movement for influencing the movement of the avatar on the track. The track may in that case be an ice skating rink or oval or an inline roller skating rink or the like.

In one embodiment of the interactive movement device, the at least two sensors are disposed laterally of the sliding floor, between the stop blocks.

An image recording system, such as a video camera or the like, connected to the electronic processing unit is provided for recording and analysing movements of the user and copying the user, for example in the avatar displayed on the image display unit.

According to a third aspect, the invention provides an elongated sliding floor for facilitating movement to be executed by a user, comprising a sensor system arranged for detecting first and second movements substantially along a finite, imaginary straight line in the longitudinal direction of the sliding floor, as set forth in the foregoing.

In one embodiment of the invention, a sliding floor which slopes slightly upwards in longitudinal direction at its ends is provided.

According to a fourth aspect, the invention provides a computer programme product comprising a data storage device for storage thereon of computer instruction data, which computer programme product is designed for carrying out the method according to the invention if the computer instruction data are loaded in a working memory of an electronic processing unit and executed by the electronic processing unit.

The data storage device may be any type of data storage device, such as a floppy disk, a memory stick, a hard disk and the like, but also an electric, optical or magnetic data signal carrier. The invention will now be described in more detail with reference to the appended drawings, explicitly without being limited to the embodiments described and illustrated herein.

Figure 1 schematically shows an example of an embodiment of an interactive movement device according to the invention.

Figure 2 is a flow diagram of an example of the invention.

Figure 3 schematically shows an example of another embodiment of an interactive movement device according to the invention.

Figure 4 schematically shows an example of another embodiment of a sliding floor according to the invention. In figure 1 there is schematically shown an exemplary embodiment of an interactive movement device 1 for movement on a track of an avatar 10 being displayed on an image display unit 8. In the example of figure 1 , a user 2 is present on an elongated sliding floor 4. The sliding floor 4 is so designed that the sliding floor 4 has a smooth surface on the side of the user 2. This enables the user 2 to slide sideways, in the longitudinal direction of the elongated sliding floor 4, across the sliding floor 4. The user 2 may make use of lubricating substances, sliding strips or other kinds of sliding material so as to be able to slide efficiently over the sliding floor 4.

The interactive movement device 1 further comprises a sensor system 6 for detecting movements and the direction of movement 12 of the user 2 along an imaginary straight line in longitudinal direction over the sliding floor 2. In the illustrated example, the device 1 is to that end fitted with two infrared sensors 5, 14, whose detection field, illustrated in broken lines, is directed to the user at a specific angle a 9, transversely to the sliding floor 4. The sensors 5, 14 are each disposed in the longitudinal direction of the sliding floor 4, laterally therefrom, between the stop blocks 3 at positions spaced from a respective end 28, 29 of the sliding floor.

The infrared sensors 5, 14 detect movements and the direction of movement 12 of the user 2 in the same plane as that of the sliding floor 4. According to the invention, it is also possible to set at least one viewing angle in the sensors 5, 14 in a plane perpendicular to the sliding floor 4 from the sensors. This makes it possible to detect movements and the direction of movement 12 in the case of incorrectly executed sliding movements of variations thereof, for example in that the user 2 lifts one of his legs 24, 25.

The interactive movement device 1 is in particular suitable for detecting skating movements made by the user 2. A skating movement is regarded as a movement in which the user slides with his feet 26, 27 over the elongated sliding floor 4, in the longitudinal direction thereof, from one end 28 of the sliding floor 4, i.e. from one of the stop blocks 3, to the other end 29 of the sliding floor 4, i.e. the opposite other stop block 3. A correct skating stroke is characterised in that the user 2 pushes off with his right leg 25 first and subsequently pulls in his left leg 24.

The push-off with the right leg 25, being a first movement, is detected by the interactive movement device 1 in that the movement activates the sensors 5, 14 in succession. Starting from a position on the extreme left of the sliding floor 4, seen from the user 2, i.e. near the end 28, the sensor 5 will be activated first as a result of the user 2 passing through the detection field of the sensor 5 with his right leg 25 and/or right foot 27. The movement device 1 will detect this as a movement. Because subsequently the sensor 14 is activated, since the right foot 27 or the right leg 25 of the user 2 subsequently passes the sensor 14, the direction of movement of the right leg 25 is detected from the succession of the activations of the sensors 5, 14. The movement device 1 , or the processing device 7 thereof, detects this as a first movement in a direction to the right, that is, in the direction from the end 28 to the end 29 of the sliding floor. The detection of the recovery with the left leg 24 or the left foot 27 is detected in a comparable manner by the movement device 1. That is, first the sensor 5 is activated and then the sensor 14. This is detected by the movement device 1 , or the processing device 7 thereof, as a next second movement in the same direction, i.e. to the right, which in this case causes the movement 13 of the avatar 10 on the track 1 to be manipulated.

A next correct skating movement, i.e. starting with the push-off with the left leg 24 or the left foot 26, results in detection of a movement to the left, i.e. from the end 29 to the end 28 of the sliding floor 4, as a result of the activation of the sensor 14 and subsequently of the sensor 5. Correct recovery with the right leg 25 or the right foot 27 is detected as a next second movement in the same direction, i.e. to the left, as a result of activation in the same order of the respective sensors 14, 5, etc.

Although infrared sensors 5, 14 are used in this example for detecting movements and the direction of movement 12 of the user 2, also other types of sensors are suitable for this purpose, among which light lock sensors, RFID sensors, radar systems, capacitive or inductive sensors in or under the sliding surface of the sliding floor, etc.

The sensor system 5 is designed for converting, by means of a processing unit 7, a detected first movement in one direction and a next second movement substantially in the same direction detected by the sensor system 6 into a manipulation of the movement 13 of the avatar 10 on a track 1 1 as displayed on the image display unit 8. The processing unit 7 shown in the figure may also be integrated in the sensor system 6 or in the image display unit 8.

To adapt the sliding floor 4 for use by all users 2, for example both children and adults, the sliding floor 7 comprises moving means 15 for moving the movable stop blocks 3 across the sliding floor 4. As a result, the distance between the two stop blocks 3 can be adjusted, making the device 1 suitable for use both by tall users, who make relatively long sliding movements, and by smaller users, who make relatively small sliding movements.

The sensor system 6 is further arranged, by comprising the processing unit 7, for determining the manipulation of the movement of the avatar 10 on the track 1 1 partially on the basis of the distance between the two stop blocks 3. The distance between the two stop blocks 3 can be determined, for example, by making use of setting means in the electronic processing unit 7, which can be set by the user 2, or by additional sensors that determine the distance.

The interactive movement device 1 further comprises a second sensor systems 16 comprising two sensors 17. The sensors 17 are designed for detecting a vertical movements of the user in 2 and coupling the detection signal to the electronic processing unit 7. In this way the movement device 1 makes it possible to detect ducking or jumping movements of the user 2, for example.

The image display device 8 further comprises an image recording system 19 for recording images of the user 2. In an example according to the invention, the recorded images are used by the image recording system 19 for projecting the user's head 20 on the avatar 10.

The movable stop blocks 3 may also comprise pressure sensors 18 for determining the force exerted on the stop blocks 3 by the user 2. Other sensor types may also be used for determining the force, for example sensor based on our RADAR, infrared, acceleration, etc. The manipulation of the movement 13 of the avatar 10 is determined partially on the basis of the force by the electronic processing unit 7.

Figure 1 shows an example of an interactive movement device 1 , in which a skating movement of the user 2 executed in the longitudinal direction of the sliding floor 2 is detected and simulated on the image display unit 8 in a forward movement 13 of the avatar 10 on the track 1 1 . The interactive movement device 1 is also suitable for simulating further games, sports or fitness exercises taking place in the longitudinal direction of the sliding floor. Furthermore, different users on different sliding floors can play against one another and the like.

Speed, time and distance can be measured and/or be detected by means of the sensors 5, 14, which are stationarily disposed in front of the sliding floor 4. This makes it possible to determine the effects of different skating techniques on the track 1 1 being covered.

The movement device being used is designed to enable the user to practice different skating movements in a virtual game or a virtual world, wherein feedback mainly of correct or correctly executed skating movements takes place by the user 2 via the image display unit. Besides providing an analysis of the skating movement and the speed, it is furthermore possible, using additional sensors, to determine the force and the acceleration of the user 2, among other things, on the basis of which data the manipulation of the movement of the avatar 10 is determined. The speed of the user 2 moving in the longitudinal direction over the sliding floor 4 is determined by means of the two sensors 5, 14, which are stationarily disposed at the front side of the user, partially on the basis of a time measurement, for example derived from the points in time at which the two sensors 5, 14 each individually detect the user 2.

The device may furthermore comprise other types of sensors as well for measuring other quantities so as to make the avatar 10 come across as realistically as possible to the user 2. Figure 2 shows a flow diagram of an example of the invention. The start (30) of the illustrated flow diagram is activated at the moment when a sensor system detects (31 ) a first movement and a direction of movement After the sensor system has detected (32) a second movement substantially in the same direction, the influencing of the movement is determined (33) via the processing unit. Following this, the processing unit adjusts the movement of the avatar of an image display unit on the basis of the manipulation as determined.

Figure 3 schematically shows an example of another embodiment of an interactive movement device 41 according to the invention. In this embodiment, the user 2 stands on a footboard 42, in this situation with his first leg 30. The user 2 uses his second leg 48 to simulate a movement in forward direction 50. In this example of the invention, the interactive movement device is designed for detecting a user 2 making scooter-riding movements.

The user 2 stands on a footboard 42, which is supported by supports 33 fixed to the underside of the footboard 42. In this case the supports 43 simulate the wheels, as it were, which are normally mounted under the footboard 42. The supports 43 may be vertically adjustable, if desired, in such a manner that the movement device 41 is suitable for use by persons of different lengths.

In the example shown in figure 2, the sensor system is made up of three sensors, viz. two position sensors 48, 51 , and one motion sensor 46. The two position sensors 47 51 are designed to detect the position of the second leg 48. If the position sensor 47 detects that the second limb 47 is located at the front side, this implies that the user 2 is readying to push off in forward direction 50 by pushing off the second leg 48 in rearward direction 44.

The position sensors 37, 41 are designed to detect the position of the second limb 48 via the pressure that is exerted on the two position sensors 47, 51. As the skilled person will appreciate, there are several other types of position sensors which are also capable of detecting the position of the second limb 48, for example by means of capacitive couplings, RFID and, etc. The motion sensor 46 detects whether a movement has taken place within an angle b 45. The motion sensor 46 may be an infrared sensor, an RFID sensor, a light lock sensor, or any other type of sensor suitable for measuring movement. According to the invention, a detected first movement in one direction and a next second movement substantially in the same direction detected by the sensor system is converted by means of an electronic processing unit (not shown) into a manipulation of the movement of the avatar on a track.

The example shown in figure 3 is an example in which the user 2 receives information feedback via an image display unit (not shown) on the user's scooter-riding movements. The avatar on the image display unit makes scooter-riding movements corresponding to those of the user 2, such that the user can easily evaluate his stepping movements himself. Figure 4 schematically shows an example of an embodiment of a sliding floor 61 according to the invention, seen in longitudinal view, in which the sliding floor 61 comprises upwardly sloping surfaces 65, 66 at both short ends. The two sloping surfaces 65, 66 shown in this example are also provided with stop blocks 63, 64, so that a user 62 can push off against the stop blocks 63, 64. In practice the slope angle c 68 is a few degrees, for example 2 - 20 degrees.

In this embodiment there is shown, by way of illustration, a sensor system 67 comprising several sensors 67a, 67b, 67c, 67d, 67e, 67f spaced some distance apart in the longitudinal direction of the sliding floor 61. Such a sensor system 67 can also be used in a similar manner with the sliding floor 4 of figure 1. By selecting a suitable sensor pair for detection of the movement, for example the sensor pair 67b, 67e or 67c, 67f, the stroke length of a skating stroke to be made can be established in advance. In practice the sliding floor 4 or the sliding floor 61 has a length in the order of 2 - 3 m, with a width of the sliding surface in the order of 0.6 - 1 m.

The present invention has been explained in the foregoing by means of a number of examples. As those skilled in the art will realise, several modifications and additions can be realised within the scope of the invention as defined in the appended claims.

Claims

1. A method for moving an avatar on a track in an environment displayed on an image display unit, using an electronic processing unit, under the influence of a movement of a user detected by a sensor system, which sensor system, during use, is positioned stationary relative to the user and is arranged for detecting movement and direction of movement, characterised in that the sensor system is arranged for detecting movement substantially along a finite, imaginary straight line, and in that the sensor system comprises at least two sensors disposed spaced from each other along said imaginary straight line, which sensors have a detection field oriented transversely to the imaginary straight line for activating a respective sensor, wherein activation of a sensor is detected as movement and wherein the direction of movement is detected from a succession of activations of the sensors, such that a first movement in one direction detected by the sensor system and a next, second movement in the same direction detected by the sensor system is converted via the processing unit into a manipulation of the movement of the avatar on the track.

2. A method according to claim 1 , wherein the user's movement is a skating movement.

3. A method according to claim 1 , wherein the user's movement is a kick scooter-riding movement.

4. A method according to one or more of the preceding claims, wherein the first and second movements detected by the sensor system are converted via the processing unit into a manipulation of the forward movement of the avatar on the track.

5. A method according to one or more of the preceding claims, wherein the avatar is moved at a certain speed on the track and the speed of movement of the avatar is manipulated by means of the processing unit in dependence on a measured period of time between the first movement and the second movement detected by the sensor system.

6. A method according to one or more of the preceding claims, wherein the sensor system is arranged for detecting, by means of the processing unit, a distance covered by the user between a first movement and a second movement along the imaginary straight line.

7. A method according to one or more of the preceding claims, wherein the avatar is moved at a certain speed on the track and the speed of movement of the avatar is manipulated by means of the processing unit in dependence on a measured period of time between a second movement in a first direction and a first movement in a second direction different from the first direction as detected by the sensor system.

8. A method according to one or more of claims 1 - 6, wherein the avatar is moved at a certain speed on the track and the speed of movement of the avatar is manipulated by means of the processing unit in dependence on a measured period of time between a second movement in a first direction and a second movement in a second direction different from the first direction as detected by the sensor system.

9. A method according to claim 7 or 8, wherein the speed of movement of the avatar is manipulated by means of the processing unit in dependence on a measured frequency with which the various movements in the first and the second direction succeed one another.

10. A method according to one or more of the preceding claims, wherein the sensor system comprises a sensor disposed spaced from the imaginary straight line, near the centre thereof, with a detection field for activating a sensor oriented substantially transversely to the imaginary straight line, in which the activation of the sensor is detected as movement, and a further sensor disposed near each end of the imaginary straight line, wherein the direction of movement is detected from the activation of a respective further sensor.

1 1. A method according to one or more of the preceding claims, wherein the extent to which the movement of the avatar on the track is manipulated can be set for various operating modes by means of the processing unit.

12. A method according to one or more of the preceding claims, wherein the sensor system comprises yet further sensors for detecting movements of the user, which movements are converted, via the processing unit, into corresponding movements of the avatar.

13. A method according to one or more of the preceding claims, wherein the sensor system comprises yet further sensors for detecting the user's physiological condition, and wherein the manipulation of the movement of the avatar on the track is partially affected, via the processing unit, by the detected physiological condition of the user.

14. An interactive movement device comprising an electronic processing unit, an image display unit connected to the electronic processing unit and a sensor system arranged for detecting a user's movement and direction of movement, which electronic processing unit is designed for moving and avatar on a track in an environment displayed on the image display unit under a influence of movement of the user detected by the sensor system, which sensor system, during use, is positioned stationary with respect to the user, characterised in that the sensor system is arranged for detecting movement taking place substantially along a finite, imaginary straight line, and in that the sensor system comprises at least two sensors disposed spaced from each other along said imaginary straight line, with a detection field oriented transversely to the imaginary straight line for activating a respective sensor, wherein activation of a sensor is detected as movement and wherein the direction of movement is detected from a succession of activations of the sensors, wherein the processing unit is further arranged for converting a first movement in one direction and a next, second movement in the same direction detected by the sensor system as detected by the sensor system into a manipulation of the movement of the avatar on the track.

15. An interactive movement device according to claim 14, comprising an elongated sliding floor, wherein the sensor system is arranged for detecting first and second movements substantially along a finite, imaginary straight line in the longitudinal direction of the sliding floor.

16. An interactive movement device according to claim 15, wherein the at least two spaced-apart sensors are arranged with their detection field oriented over the sliding floor.

17. An interactive movement device according to claim 15, wherein the at least two spaced-apart sensors are arranged with their detection field oriented transversely to the sliding floor.

18. An interactive movement device according to one or more of claims 14 - 17, comprising a further sensor, such as a pressure sensor or a force sensor, disposed at each end of the imaginary straight line.

19. An interactive movement device according to claim 16, 17 or 18, wherein the at least two sensors are fixedly connected to the elongated sliding floor, and wherein the sliding floor is further provided near each end thereof with stop blocks which are movable in the longitudinal direction of the sliding floor.

20. An interactive movement device according to claim 19, wherein said stop blocks are provided with pressure or force measuring sensors.

21. An interactive movement device according to claim 19 or 20, wherein said at least two sensors are disposed between the stop blocks.

22. An interactive movement device according to one or more of claims 14 - 21 , further comprising a sensor system provided with sensors arranged for detecting vertical movements.

23. An interactive movement device according to one or more of claims

14 - 22, further comprising an image recording system connected to the electronic processing unit for recording further movements of the user.

24. An interactive movement device according to one or more of claims

15 - 23, further comprising an elongated sliding floor and being arranged for simulating a skating movement taking place in the longitudinal direction of the sliding floor and/or further games, sports or fitness exercises.

25. An interactive movement device according to one or more of claims

15 - 24, comprising a sliding floor which comprises a surface that exhibits a slope in the longitudinal direction of the sliding floor at both ends.

26. An elongated sliding floor for use in an interactive movement device according to one or more of claims 15 - 25.

27. An elongated sliding floor for facilitating movement to be executed by a user, comprising a sensor system arranged for detecting first and second movements substantially along a finite, imaginary straight line in the longitudinal direction of the sliding floor.

28. A computer programme product comprising a data storage device for storage thereon of computer instruction data, which computer programme product is arranged for carrying out the method according to one or more of claims 1 - 13 if the computer instruction data are loaded in a working memory of an electronic processing unit and executed by the electronic processing unit.