FR2908323A1 - METHOD OF DEFINING A COMMON REFERENTIAL FOR A VIDEO GAMING SYSTEM - Google Patents

Abstract

The invention relates to a method for defining a common repository for a video game system. The system comprises at least two remotely controlled vehicles (1), a first vehicle and a second vehicle, each comprising a video sensor (19) and a reference element (69) with recognizable areas (71). The method comprises the steps of: positioning the first vehicle relative to the reference element (69) so that recognizable areas (71) are in the field of view of the video sensor (19) of the first vehicle; processing the image delivered by the video sensor (19) of the first vehicle positioned to locate the recognizable areas (71) in the image; deducing the position of the first vehicle relative to the reference element (69) by locating the recognizable areas (71); transmitting the position of the first vehicle to the second vehicle.

Description

The invention relates to a method for defining a common reference system

  for a video game system. In particular, the invention also relates to the tracking of objects in this common frame of reference. WO 01/95988 A1 discloses a hunting game for two remotely controlled vehicles. The vehicles are controlled by two users and one of the two vehicles chases the other. The remotely operated vehicles are each equipped with a video camera. The images delivered by the video camera are communicated to two computers, each of the two computers being used by one of the two players controlling one of the two remotely controlled vehicles. Each player can see on the screen of his computer the image delivered by the corresponding video camera of his remote control vehicle. In the application of the hunting game mentioned above, the video image of the hunter vehicle is processed in such a way that, if the hunted vehicle enters the field of view of the hunter vehicle's video camera, the computer nurnerically removes the image corresponding to the vehicle driven from the image delivered by the video camera of the hunter vehicle. The removed image of the chased vehicle is replaced by a virtual character of the video game.

  In this context, the document WO 01/95988 envisages that the driven vehicle is equipped with reflective elements on the essential points of its outer surface. These reflective points serve to facilitate the detection of the image of the vehicle driven in the video image delivered by the video camera of the hunter vehicle.

  This document therefore describes the use of recognizable areas, that is to say reflective elements present on the driven vehicle.  However, such a system does not allow the placing in the same repository of two remotely controlled vehicles during the initialization of a video game.  The object of the present invention is therefore to provide such a method for defining a common reference frame.  According to the invention, this object is achieved by a method of defining a common frame of reference for a video game system, the system comprising: at least two remotely controlled vehicles, a first vehicle and a second vehicle, each comprising a video sensor; and a reference element with recognizable areas; The method comprising the steps of: positioning the first vehicle relative to the reference element so that recognizable areas are within the field of view of the video sensor of the first vehicle; Processing the image delivered by the video sensor of the first vehicle positioned to locate recognizable areas in the image; deduction of the position of the first vehicle relative to the reference element thanks to the identification of the recognizable areas; transmitting the position of the first vehicle to the second vehicle.  The common reference system according to the invention is a single repository shared by the two remotely controlled vehicles making it possible to initialize the respective positions of the two remotely controlled vehicles with respect to a single point of origin at the beginning of the game and to track the movements of the two vehicles during the course of the game.  Preferably, the origin point of the common reference frame is defined by the reference element comprising recognizable areas.  In a preferred application, the reference element is a separate and independent real object of the two vehicles, including a bridge or pylon, serving to define a starting point for a running game between the two vehicles.  Alternatively, the reference element may also be integrated with the second vehicle in the form of an arrangement of optical elements.  In the latter case, the reference element may be an arrangement of headlights or reflective elements such as found at the front and rear of motor vehicles.  Preferably, the recognizable areas of the corn-30 reference element take optical elements, including flashing LEDs at a known frequency or reflective patterns.  The two remotely controlled vehicles are preferably toys in the form of land vehicles, including race cars or tanks, or air vehicles, including quadcopters.  According to the steps of the method of the invention, first, the first vehicle is placed in the vicinity of the reference element.  The location of the first vehicle shall be chosen in such a way that the recognizable areas of the reference element are within the field of vision of the vehicle's video sensor.  If the first vehicle is placed in such a way that the image delivered by its video sensor does not reproduce the part of the reference element containing recognizable areas, the subsequent image processing will not be able to detect recognizable areas. -sables in the image delivered by the video sensor.  In this case, the first vehicle will have to be relocated to allow identification of the recognizable areas in the image.  Once the recognizable areas have been identified in the image, the position of the first vehicle relative to the reference element is deduced therefrom.  This position may be expressed as two- or three-dimensional coordinates and defining the position of the first vehicle with respect to the reference element which serves as the point of origin in the common repository.  Finally, the position of the first vehicle that has been deducted is transmitted to the second vehicle.  Preferably, the steps of the image processing as well as the deduction of the position of the first vehicle are performed by a computer on board the first vehicle.  Preferably, the video game system may further comprise at least two electronic entities, including two portable consoles each used to remotely control one of the two vehicles.  In this case, the video images delivered by the video sensors of the remotely controlled vehicles can be displayed on screens of the electronic entities and the image processing steps and position deductions can be performed by computers present in the electronic entities. .  Preferably, the deduction of the position of the first vehicle relative to the reference element is done by triangulation.  In addition, the communication between the remotely controlled vehicles and, where appropriate, between the electronic entities and the remotely controlled vehicles, such as the transmission of the position of the first vehicle to the second vehicle, can be carried out by short-distance radio transmission, no. - 2908323 4 by Bluetooth protocol or WiFi (registered trademarks).  The method according to the invention has the major advantage of allowing the implementation of a single coordinate system for a video game system including several remote controlled vehicles.  Thus, during the initialization of a video game, such as a racing game or a shooter that is supposed to involve the two remotely controlled vehicles, the system is able to know the exact positions of the vehicles parties to the game, This is a prerequisite for reliable display and tracking of vehicle position during the video game.  Such a method is particularly advantageous for a video game system in which the remote-controlled vehicles operate on any real terrain that is not particularly adapted for video games, such as a park or a garden, and where the game takes place in a virtual game zone based on real terrain.  When the different toys are put in the same single repository, one or more virtual objects can be added in the game space.  For example, they may be virtual pads delimiting a car racing circuit, or virtual rings visualizing a circuit for flying quadcopters.  The added virtual objects can move in the repository.  They can be for example virtual cars moving on a circuit or enemy planes moving around quadcopters.  The objects are then displayed by inlay in a 3-dimensional space of the game console used to control the toy.  During the game period, the different vehicles, for example cars or quadrocopters, preferably estimate their displacement and their position.  This is done through on-board sensors that can be accelerometers, gyroscopes, video cameras, pressure sensors, analog voltage sensors on the propulsion and steering engines.  The measurements of these sensors can be merged and filtered by algorithms of a microcontroller embedded on the remotely controlled vehicle.  Then, by radio means, each toy can transmit its position to all other toys, either whenever it moves, or with a given frequency, for example 25 times per second.  In this way, throughout the course of the game and in the common repository established at the initial game sequence, the coordinates of moving gears are kept up to date.  Thanks to the addition of virtual objects in the 3-dimensional space of the video game and the real-time updating of the positions of the toys, a complete interaction can be staged by the designer of the video game.  The 5 different video toys can participate in the same game.  Players can control them.  The game scenarios can be a car race on a virtual circuit, a shooting game against each other or with each other against virtual enemies, or a formation flight when flying a plane or a quadricopter.  Exemplary embodiments of the methods of the invention, as well as devices and systems embodying embodiments of the invention will now be described with reference to the accompanying drawings in which like reference numerals refer to a preferred embodiment of the invention. figure to the other identical or functionally similar elements.  FIG. 1 illustrates an overview of the video game system according to the invention. FIGS. 2a and 2b show two examples of remote-controlled vehicles according to the invention; FIGS. 3a and 3b are schematic diagrams of the electronic elements of a remotely controlled vehicle according to the invention; Figures 4a to 4c show several examples of aerial images used in the video game system according to the invention; FIG. 5 illustrates a principle of defining playing zones according to the invention. FIGS. 6a and 6b show the two-dimensional view according to the invention. FIGS. 7a to 7c show the perspective view according to the invention; FIG. 8 is an example of the point of view delivered by the video camera on board the remote-controlled vehicle according to the invention; Figure 9 is an example of display on the portable console according to the invention; FIG. 10 illustrates the virtual positioning of a racing circuit on an aerial image according to the invention; Fig. 11 illustrates the display adjustment method according to the invention; Figures 12a to 12c illustrate a method of defining a common reference system according to the invention; and Figures 13a to 13c illustrate an alternative version of a racing game according to the invention.  Figure 1 gives an overview of a system according to the invention.  The system includes a video game system consisting of a remotely operated vehicle 1 (referred to by the acronym BU, that is, Blue Tooth Toy, or \ NIT, ie WiFi Toy). as well as a portable console 3 which communicates with the vehicle 1 via a Bluetooth link 5.  The vehicle 1 can be remotely controlled by the portable console 3 through the Bluetooth link 5.  The vehicle 1 is in relation with several satellites 7 through a GPS sensor on the vehicle 1.  The portable console 3 can be equipped with a high-speed wireless Internet access connection, such as a WiFi connection 9.  This connection allows the console 3 to access the Internet 11.  Alternatively, if the portable console itself is not equipped with an Internet connection, an indirect connection to the Internet 13 can be envisaged through a computer 15.  A database 17 containing terrestrial aerial images is accessible through the Internet 11.  Figures 2a and 2b show by way of example two different embodiments of the remotely controlled vehicle 1.  In Figure 2a, the remote control toy 1 is a race car.  This race car 1 has a video camera 19 integrated in its roof.  The image delivered by the video camera 19 is communicated to the portable console 3 by the Bluetooth link 5 to be displayed on the screen of the portable console 3.  Figure 2b shows that the remote-controlled toy 1 may also consist of a quadricopter with 4 propellers 21.  In the same way as for the race car, quadcopter 1 has a domed video camera 19 in the center of it.  Of course, the remotely operated vehicle 1 can also be in the form of another craft, for example in the form of a boat, a motorcycle or a tank.  In short, the remotely operated vehicle 1 is essentially a piloted vehicle that transmits the video, to which sensors are added.  Figures 3a and 3b schematically show the main electronic components of the remotely operated vehicle 1.  Figure 3a details the basic electronic components.  A computer 23 is connected to various peripheral elements such as the video camera 19, motors 25 for moving the remote controlled vehicle, and various memories 27 and 29.  The memory 29 is an SD card, that is to say a removable digital data storage memory card.  This card 29 can be deleted but preferably it is kept because its function is to record the video image delivered by the camera 19 to thereby allow the ironing of 20 recorded video sequences.  Figure 3b shows the additional functions on the remotely operated vehicle 1.  The vehicle 1 essentially comprises two additional functions: an inertial unit 31, comprising three accelerometers 33 and three gyroscopes 35, and a GPS sensor 37.  The additional functions are connected to the computer 23, for example by serial link.  It is also possible to add a Universal Serial Bus (USB) connection to the vehicle 1 in order to be able to update the software running in the vehicle's electronic system 1.  The inertial unit 31 is an important element of the vehicle 1.  It makes it possible to estimate in real time and precisely the coordinates of the vehicle.  It estimates in all nine coordinates for the vehicle: the positions X, Y, Z of the vehicle in the space; the orientation angles a, 3, y of the vehicle (Euler angles); as well as the speeds VX, VY, VZ on each of the three Cartesian axes X, Y and Z.  These displacement coordinates come from three accelerometers 33 as well as three gyroscopes 35.  These coordinates can be obtained after a Kalman filter at the output of the sensor measurements.  More specifically, a microcontroller performs the measurement and retransmits by serial link or serial bus (Serial Peripheral Interconnect, 5 SPI) to the computer 23.  The computer 23 mainly performs Kalman filtering and returns via the Bluetooth connection 5 the determined position of the vehicle 1 to the game console 3.  The calculation of the filtering can be optimized: the computer 23 knows the instructions which are sent to the propulsion and steering engine 25.  It can use this information to establish the prediction of the Kalman filter.  The instantaneous position of the vehicle 1 determined using the inertial unit 31 is returned at a frequency of 25 Hz to the game console 3, that is to say that the game console receives a position per image.  If the computer 23 is too loaded in calculation, the raw measurements 15 from the inertial unit 31 can be sent to the game console which will itself perform the Kalman filter in place of the computer 23.  This solution is not desirable for the simplicity and the coherence of the system since it is better that all the calculations of the video game are made on the console 3 and that all the acquisition of the data is made by the vehicle 1 but it is nevertheless conceivable.  The sensors of the inertial unit 31 can be made in the form of piezoelectric sensors.  These sensors have a large variation in temperature, which means that they must be kept at a constant temperature with a temperature probe and a rheostat or that, using a temperature probe, the temperature must be measured at the same temperature. of these piezoelectric sensors and compensate by software the variation of the sensors at the temperature.  The GPS sensor 37 is not an essential function of the remotely operated vehicle 1.  However, it allows a great wealth of functions at a modest price.  All that is needed is an entry-level GPS, which operates mainly outdoors and which does not have a need for real-time tracking of the journey since the real-time monitoring of the journey is provided by the inertial unit 29.  It is also possible to use a GPS in the form of software.  The game console 3 is any portable console available 2908323 9 on the market.  Examples currently known of portable consoles are the Sony Playstation Portable (PSP) or the Nintendo DS Nintendo.  It can be provided with a Bluetooth 4 (dongle) key (cf.  Fig.  1) to communicate by radio with the vehicle 1.  Database 17 (Figure 1) contains an aerial image library preferably from around the world.  These may be photographs obtained from satellites or planes or helicopters.  Figures 4a to 4c show various examples of aerial images obtainable from the database 17.  The database 17 is accessible over the Internet so that the console 3 can access it.  The aerial images downloaded from the database 17 are used by the game console 3 to create synthetic viewpoints that are integrated into video games running on the console 3.  The method according to which the console 3 acquires the aerial images of the database 17 will now be described.  For this, the user of the console 3 places his remote-controlled vehicle 1 in a real place, such as in a park or a garden, where he wants to play.  With the GPS sensor 37, the vehicle 1 determines its terrestrial coordinates.  These are then transmitted via the Bluetooth or WiFi link 5 to the console 3.  The console 3 then connects via the WiFi connection 9 via the Internet to the database 17.  If there is no WiFi connection at the place of play, the console 3 stores the determined terrestrial position.  Then, the player moves to a computer 15 having access to the Internet.  The player connects the console 3 to the computer and the connection 25 between the console 3 and the database 17 is then done indirectly through the computer 15.  Since the connection between the console 3 and the database 17 is established, the terrestrial coordinates stored by the console 3 are used to search aerial images or maps in the database 17 which correspond to the terrestrial coordinates.  Once an image reproducing the land area in which the vehicle 1 is found in the database 17, the console 3 downloads the aerial image found.  FIG. 5 gives an example of a geometric definition of a two-dimensional game background used for a video game involving the console 3 and the vehicle 1.  The squares and rectangles shown in FIG. 5 represent aerial images downloaded from the database 17.  The set square A is divided into 9 intermediate rectangles.  Of these 9 intermediate rectangles the central rectangle itself is subdivided into 5 16 squares.  Of these 16 squares, 4 squares in the center represent the game zone B itself.  This game zone B can be loaded with the maximum definition of the aerial images and the immediate surroundings of the game zone B, that is to say the remaining 12 squares of the 16 squares, can be loaded with a lesser definition of the images. and the 10 margins of the game represented by the 8 undivided rectangles at the periphery of the sub-divided central rectangle can be loaded with aerial images of the database with still less definition.  By playing on the definition of the different images near or far from the center of the game, the amount of data to be stored and processed on the console is optimized and the visual effect of their placing in perspective is not affected.  The farthest images of the center of the game are displayed with a definition corresponding to their distance.  The downloaded aerial images are used by the console 3 to create different viewpoints that can be used in corresponding video games.  More precisely, it is envisaged that the console 3 is capable of creating at least two different points of view from the downloaded aerial images, namely a two-dimensional vertical point of view (cf.  Figures 6a and 6b) and a three-dimensional perspective viewpoint (cf.  Figures 7a to 7c).  Figure 6a shows an aerial image as downloaded by the console 3.  The remotely operated vehicle 1 is located somewhere on the ground visualized by the aerial image of Figure 6a.  This aerial image is used to create an image of synthesis as shown schematically in Figure 6b.  Rectangle 39 represents the aerial image of Figure 6a.  On this rectangle 39 are inlaid three graphical objects 41 and 43.  These graphic objects respectively represent the position of the remotely operated vehicle on the game area represented by the rectangle 39 (cf.  spot 43 which corresponds to the position of the remotely controlled vehicle) and the position of other real or virtual objects (cf.  the crosses 41 41, for example may represent the position of real competitors or virtual enemies of a video game).  It is conceivable that the software of the vehicle 1 ensures that it does not leave the game area defined by the rectangle 39.  Figures 7a and 7c show the perspective viewpoint that can be achieved by the console 3 from the downloaded aerial images.  This perspective image comprises a "ground" 45 in which is inserted the downloaded aerial image.  The sides 47 are virtual images of infinite perspective, an example of which is shown in FIG. 7b.  These are generated by the real-time 3-dimensional graphics engine of the game console 3.  As with the two-dimensional viewpoint, graphical objects 41 and 43 indicate to the players the position of their own vehicle (43) as well as the position of co players or potential enemies (41).  For the creation of the points of view, it is also possible to download the elevation mesh of the database 17.  FIG. 8 shows the third point of view 49 that is envisaged in the video game system, namely the point of view delivered by the video camera 19 on board the remotely operated vehicle 1.  Figure 8 shows an example of such a point of view.  On this real video image, we incrust different virtual graphic objects according to the video game used by the player.  Figure 9 shows the game console 3 with a display that summarizes how previously discussed points of view are presented to the player.  There is clearly the point of view 49 corresponding to the video image delivered by the video camera 19.  The viewpoint 49 includes virtual inlays 51 which in the case of FIG. 9 are virtual pads delimiting the path of a virtual circuit.  In point of view 49, one can also see the actual hood 53 of the remotely operated vehicle 1.  The second viewpoint 55 corresponds to the two-dimensional vertical viewpoint shown in FIGS. 6a and 6b.  The point of view 55 consists of the reproduction of an aerial image of the playing field, on which is embedded a virtual race circuit 57 with a point 59 moving on the virtual circuit 57.  This point 59 indicates the current position 35 of the unmanned vehicle 1.  Depending on the video game, the two-dimensional viewpoint 55 may be replaced by a perspective view as previously described.  Finally, the display as shown in FIG. 9 comprises a third zone 61 which here shows the virtual gas gauge of the vehicle 1.  An example of a video game for the video game system shown in FIG. 1 will now be described.  The example is a car race carried out on real terrain using the remotely operated vehicle 1 and the game console 3, the particularity of this game being that the race circuit is not really demarcated on the real ground but is only positioned virtually on the real playing field in which the vehicle 1 is moving.  To initialize the racing video game, the user proceeds to the acquisition of the aerial image corresponding to his playing field in the manner that has already been described previously.  Once the game console 3 has downloaded the aerial image 39 reproducing a vertical view of the playing field on which the car 1 is, the software draws a virtual race circuit 57 on the downloaded aerial image 39 as this is shown in Figure 10.  The circuit 57 is generated in such a way that its virtual starting line is positioned on the aerial image 39 close to the geographical position of the vehicle 1.  This geographical position of the vehicle 1 corresponds to the coordinates delivered by the GPS module, to which are added known physical values of the dimensions of the vehicle 1.  With the keys 58 of the console 3, the player can rotate the circuit 57 around the starting line, submit the circuit 57 to 25 a homothety keeping the starting line as the invariant point of the homothety (The homothety is achieved in defined proportions corresponding to the maneuverability of the car), or drag the circuit around the starting line.  It is also possible to slide the starting line on the circuit, the vehicle in front of this case to join the starting line to start the game.  All this can for example be useful if the garden of the house where the player wishes to perform the video game is not large enough for the circuit initially designed by the software.  The player can thus change the position 35 of the virtual circuit until it is well positioned on the real playing field.  In the context of a flying video toy which is one of the preferred applications, for example a quadrocopter, an inertial unit of the flying machine is used to stabilize it.  A flight instruction is transmitted by the game console to the flying machine, for example hovering right turn or landing.  The microcontroller software on board the flying machine uses its control surfaces: speed modification of the propellers or control of aerodynamic control surfaces to make the measurements of the inertial unit coincide with the 10 vol setpoint.  Similarly, in the case of the motor vehicle video toy, instructions are retransmitted by the console to the vehicle microcontroller, for example turn right or brake or speed 1 meter / second.  The video toy may have main sensors, for example a GPS and / or an inertial unit composed of accelerometers or gyroscopes.  It may also have additional sensors such as a video camera, a means of counting the turns of the wheels of a car, an air pressure sensor for estimating the speed for a helicopter or an airplane, a pressure sensor of a car. water to determine the depth for a submarine, or analog-to-digital converters for measuring power consumption at various points of the on-board electronics, such as the consumption of each electric motor for propulsion or steering.  These measurements can be used to estimate the position of the video toy on the circuit during the entire game sequence.  The measurement mainly used is that of the inertial unit which includes accelerometers and / or gyroscopes.  The measurement thereof can be enhanced by using a filter, for example a Kalman filter, which makes it possible to reduce the noise and to merge the measurements of the other sensors, cameras, pressure sensors, measurement of the electrical consumption of the motors, etc. .  For example, the estimated position of the vehicle 1 may be periodically recalibrated using the video image provided by the camera 19 and estimating the motion from significant fixed points of the scenery in the image which are preferably points. high contrast of the video image.  The distance to the fixed points can be estimated by minimizing matrices according to known triangulation techniques.  The position can also be recalibrated over a greater distance (about 50 meters) using GPS, particularly recent GPS modules using satellite signal phase measurements.  The speed of the video toy can be estimated by counting the wheel turns using for example a coded wheel.  If the video toy is powered by an electric motor, its speed can also be estimated by measuring the consumption of said motor.  This requires knowledge of the performance of the engine at different speeds, which can be measured beforehand on a test bench.  Another way to estimate the speed is to use the video camera 19.  In the case of a car or a flying machine, the video camera 19 is fixed or its position is known relative to the body of the machine and its focal length is also known.  The microcontroller of the video toy performs video coding of the MPEG4 type, for example using the H263 or H264 encoding.  This coding involves the computation of motion prediction of subset of the image between two video images.  For example, this subset may be a square of 16 * 16 pixels.  The motion prediction is preferably performed by a hardware accelerator.  The overall movements of the subsets of the image provided an excellent measure of speed of the craft.  When the machine is stationary, the sum of the movements of the subsets of the image is close to zero.  When the machine advances in a straight line, the image subsets move away from the vanishing point with a speed proportional to the speed of the machine.  In the context of the car racing video game, the screen is divided into several elements as shown in Figure 9.  The left-hand element 49 displays the image delivered by the video camera 19 of the car 1.  The right-hand element 55 makes it possible to see the circuit map and the competing cars (cf.  the point of view at the top right of Figure 9).  Indicators can visualize the actual speed (at the scale of the car).  Game parameters can be added, such as speed 35 or fuel consumption of the car, which can be simulated 2908323 15 (as for a race of a grand prix of formula 1).  As part of this video game, the console can also memorize races.  If you only have one car, you can run against yourself.  In this case, on the screen, it is possible to envisage displaying the three-dimensional image in transparency of the position of the car during a stored tour.  FIG. 11 details the manner in which the virtual inlays 51, that is to say the pads of the racing circuit, are adapted in the display 49 corresponding to the point of view of the video camera on board the vehicle 1.  Figure 11 shows the topography 63 of the actual terrain on which the vehicle 1 moves by running the racing video game.  It is noted that the ground of the playground is not flat but has descents and climbs.  The slope of the terrain varies, which is represented by the arrows 65.  Therefore, overlaying the boundaries of the circuit 51 on the video image can not be static but must adapt according to the slope of the playing field.  To take account of this problem, the inertial unit 31 of the vehicle 1 has a sensor of the attitude of the vehicle.  The inertial unit makes a real-time acquisition of the instantaneous attitude of the vehicle 1.  From the instantaneous values of the attitude, the electronics of the vehicle 1 estimate two values, namely the slope of the ground (that is to say the long-term average of the attitude) and the roughness of the circuit ( that is, the short-term average of the plate).  The software uses the slope value to compensate the display, i.e. to move the inlaid pads 51 onto the video image as indicated by the arrow 67 in FIG.  It is also expected that the display of the pads display software 51 is learning.  After the vehicle 1 has made a first turn on the virtual circuit 57, the slope and roughness values are known throughout the circuit, stored and used in the prediction component of a Kalman filter which re-estimates the slope and roughness in the next round.  The embedding of the virtual pads 51 on the video image can also be improved by displaying only discontinuous pads and displaying a small number of pads, for example only 4 pads on each side of the road.  In addition, the remote pads may be of a different color and only serve as indications and not as actual definitions of the contour of the track.  In addition, the remote studs may also be more spaced than the nearby studs.  Depending on the application envisaged, it may be necessary to estimate in addition the roll motion of the car to adjust the position of the pads 51, that is to say the possible inclination of the car by relative to its longitudinal axis.  The estimation of the roughness of the circuit is preferably used to extract the measurement of the slope in the data from the sensors.  In order to precisely define the geometry of the ground on which the circuit is placed, a learning phase can be conducted by the video game.  This learning phase is advantageously performed before the game itself, slow and constant speed controlled by the console 15 games.  The player is asked to perform a first lap of circuit during which the measurement of the sensors is memorized.  At the end of the lap, the value of the elevation at many points of the circuit is extracted from the stored data.  These elevation values are then used during the game to properly position the virtual pads 51 on the video image.  Figures 12a to 12c detail a method of defining a common repository when the racing game is performed by two or more remotely operated vehicles 1.  In this case, we are in the presence of two players each having a remote control vehicle 1 and a portable console 3.  These two players want to perform against each other with their two vehicles 1 a race car on a virtual circuit 57.  The initialization of such a game to two can for example be done by selecting the mode "two cars" on his console.  This causes the Bluetooth or WiFi protocol of each car 1 to enter "partner search" mode.  When the partner car is found, each car 1 announces at its console 3 that the partner has been found.  One of the consoles 1 then makes the selection of the game parameters: choice of the circuit as previously described, the number of laps, etc.  Then the countdown is started on the two consoles: the two cars communicate with each other using the Bluetooth protocol or WiFi.  In order to simplify the exchanges between the different devices each car 1 communicates with its console 3 but not with those of other cars.  The cars 1 then send their coordinates in real time and each car 1 sends its own coordinates and the coordinates of the competitor (s) to its pilot console.  On the console, the display of the circuit 55 shows the positions of the cars 1.  In such a car game, the Bluetooth protocol is in a Scatternet mode.  One of the cars is then Master and the console 10 which is paired to it is Slave, as well as the other car which is also Slave.  In addition, the cars exchange their position with each other.  Such a racing game with two or more remote-controlled vehicles 1 requires, during the initialization of the game, that the cars 1 be placed in the same common repository.  Figures 12a to 12c detail the method of defining a corresponding common reference.  As shown in Figure 12a, the remotely operated cars 1 with their video camera 19 are positioned in front of a bridge 69 placed on the real playground.  This actual bridge 69 represents the start line and is equipped with four LEDs 71.  Each player puts his car 1 so that at least two LEDs 71 are visible on the screen of his console 3.  LEDs 71 have known colors and can flash at a known frequency.  In this way, the LEDs 71 can be easily identified in the video images respectively delivered by the two video cameras 19.  A computer present on each of the vehicles 1 or each of the consoles 3 performs image processing and estimates by triangulation the respective position of its car 1 with respect to the bridge 69.  Once a car 1 has estimated its position with respect to the bridge 69, it transmits its position to the other car 1.  The two cars 1 having 30 each estimated their position relative to the bridge 69, we deduce the position of the cars 1 between them and the race can begin.  Figure 12b is a front view of the bridge 69 showing the four LEDs 71.  FIG. 12c shows a representation of the display of a console 3 during the procedure for determining the position of a vehicle 1 with respect to the bridge 69.  In FIG. 12c, it can clearly be seen that the computer performing the image processing has succeeded in detecting the two flashing LEDs 71, which is indicated in FIG. 12c by two reticles 73.  Such a definition of a common reference system with respect to the ground and between the vehicles is particularly useful for a racing game (each vehicle must refer to the race circuit).  For other video games, such as a shooting game, the definition of a common repository is simpler: for each vehicle it is sufficient to know its position relative to the competitors.  Figures 13a to 13c are snapshots corresponding to an alternative version of the racing video game, the racing game not involving this time not one or more cars 1 but rather one or more quadcopters 1 as shown in Figure 2b.  In this case, where the remotely operated vehicle 1 is a quadricopter, the inertial unit is not only used to transmit the three-dimensional coordinates of the toy to the console 3, but also to provide the processor on board the quadricopter 1 the necessary information for the program that stabilizes quadricopter 1.  With a quadrocopter, the race is no longer on a track as in the case of a car but in three dimensions.  In this case, the race circuit is no longer represented by inlaid virtual pads as shown in FIG. 9, but for example by virtual circles 75 embedded in the video image (cf.  Fig.  13b) delivered by the video camera 19 that float in space.  The player must direct his quadrocopter 1 through 25 virtual circles 75.  As for the car, three views are possible: the video image delivered by the video camera 19 with virtual inlays, the vertical view based on a downloaded aerial image and the perspective view also based on a satellite or aerial image 30 downloaded.  Figure 13b gives an overview of a video image with virtual circles embedded 75 as it may be in a game involving a quadrocopter.  The positioning of the circuit on the downloaded aerial image is performed in the same way as for the car race.  The circuit is 2908323 19 positioned by the player by hand in order to position it correctly according to obstacles and buildings.  In the same way, the user can homothétier the circuit, rotate around the starting point and drag the starting point on the track.  The step of positioning the circuit 57 is shown in FIG. 13a.  In the same way as for the car race, we plan for a race involving several

  quadricopters a separate element defining the starting line, for example a pylon 77 provided with three flashing LEDs or reflecting elements 71. The quadrocopters or drones 10 are aligned in the same frame thanks to the image of their camera 19 and the significant points in the image represented by the three LEDs 71 of the pylon 77 which are flashing. Since all the geometric parameters are known (camera position, focal length, etc.), the apparatus 1 is positioned unambiguously in the common reference frame. More precisely, the machine 1 is positioned in such a way that it is placed on the ground with the tower 77 in view, it is verified on the screen of its console 3 that the three LEDs are clearly visible. The three flashing LEDs 77 represent the significant points for the recognition of the marker. The fact that they are flashing at a known frequency makes it easier to identify them by the software. Once the position with respect to the known pylon 77, the quadricopters 1 exchange the information (each passes to the other its position relative to the pylon 77) and in this way each quadricopter 1 deduces the position of its competitor.

The race can begin from the position of the quadrocopter 1 at which the detection of the pylon 77 by image processing has been carried out. But of course the race can also start from another position, the inertial unit can memorize the movements of the quadricopters 1 of their initial position vis-à-vis the pylon 77 before the race. Another game considered is the shooter between two or more vehicles. For example, the shooting game may involve tanks with a video camera stationary or installed on a turret or quadrocopters or quadricopters against tanks. In this case, it is not necessary to know the position of each machine with respect to a circuit but simply to know the position of each machine relative to each other. A simpler procedure can be implemented. Each machine has flashing LEDs at a known frequency, with known colors and / or geometry known in advance. Thanks to the communication protocol each machine exchanges information with others about its type, the position of its LEDs, their flashing frequency, their color, etc. Each gear is placed so that at the beginning of the game the LEDs of the other machine is in the field of view of its video sensor 19. In carrying out a triangulation operation it is possible to determine the position of each machine relative to each other. The game can then begin. Each machine knows, thanks to its inertial unit and its other means of measurement, its position and its movement. He transmits them to the other machines. On the video console, the image of a viewfinder is embedded for example in the center of the video image transmitted by each machine. The player may give a projectile firing instruction to another craft. At the time of the shot, knowing the positions retransmitted by the other machines and its own position, orientation and speed, the shooter's software can estimate if the shot has reached its goal. The firing may simulate a projectile that immediately arrives at its target, or simulate the parabolic course of a munition, or the path of a guided missile. The initial velocity of the machine that fires, the velocity of the projectile, the simulation of external parameters, for example atmospheric conditions, can be simulated. In this way, the shooting of the video game can be made more or less complex. The trajectory of missile ammunition, tracer bullet, etc. can be superimposed on the console. Machines such as rolling or flying vehicles can also estimate the position of the other gears in the game. This can be done by a pattern recognition algorithm using the image of the camera 19. Otherwise the gears can be provided with parts. allowing identification such as LEDs. These parts permanently allow the other machines to estimate their position in addition to the information of the inertial unit transmitted by the radio means.

35 This makes the game more realistic. For example in a game of hunting against each other, one of the players can hide behind a detail of the ground, for example behind a tree. The video game, even if it is informed by radio means of the position of the opponent, can not locate it on the video image and therefore it will invalidate the shot even if it is in the right direction. When a machine is informed by its console that it has been touched, or during another action of game, for example the simulation of lack of fuel, a breakdown or atmospheric conditions, a sequence of simulation specific to video game scenario can snap. For example, in the case of a quadrocopter, it can be jolted, no longer fly in a straight line, or it can be an emergency. In the case of a tank, it can simulate damage, drive slower or simulate the fact that its turret is blocked. The video transmission may also be modified, for example the images may arrive scrambled, darkened, or effects such as broken cockpit windows may be embedded in the video image. The video game according to the invention can mix: The actions of the players: pilot the machines; Virtual elements: a circuit or enemies 20 displayed on the game console; Simulations: instructions sent to the video toy to modify its behavior, for example an engine failure and the limitation of the speed of the vehicle or a greater difficulty of piloting.

These 3 levels of interaction make it possible to increase the realism between the video game on the console and a toy equipped with sensors and a video camera. 30

Claims (17)

  A method of defining a common repository for a video game system (1, 3), the system comprising: at least two remotely controlled vehicles (1), a first vehicle and a second vehicle, each including a video sensor ( 19); and a reference element (69) with recognizable areas (71); characterized in that the method comprises the steps of: positioning the first vehicle relative to the reference element (69) so that recognizable areas (71) are in the field of view of the video sensor (19) of the first vehicle; processing the image delivered by the video sensor (19) of the first vehicle positioned to locate the recognizable areas (71) in the image; deducting the position of the first vehicle relative to the reference element (69) by locating the recognizable areas (71); transmitting the position of the first vehicle to the second vehicle.   2. Method according to claim 1, the reference element (69) being a distinct and independent real object of the two vehicles, in particular a bridge or pylon, serving to define a starting point for a running game between the two. vehicles.   3. A method according to claim 1, the reference element (69) being integrated with the second vehicle in the form of an arrangement of optical elements.   4. Method according to one of the preceding claims, the recognizable areas (71) comprising optical elements, including flashing LEDs at a known frequency or reflecting patterns. 2908323 23   5. Method according to one of the preceding claims, the deduction of the position of the first vehicle relative to the reference element (69) being effected by triangulation.   6. Method according to one of the preceding claims, the video game system (1, 3) further comprising at least two electronic entities (3), including two portable consoles, each used to remotely control one of the two vehicles (1). ).   7. Method according to one of the preceding claims, the two remote-controlled vehicles being land vehicles, including race cars or tanks, or air vehicles, including quadricopters.   8. Method according to claim 6, the communication between the electronic entities (3) and the remote-controlled vehicles (1), as well as the communication between the vehicles themselves, carried out by short-distance radio transmission (5), in particular by Bluetooth or Wifi protocol.   9. Method according to one of the preceding claims, wherein the remote-controlled vehicles (1) have means for estimating their displacement and / or their position. 25   The method of claim 9, wherein the displacement and / or position estimation means comprise the video sensor (19).   11. The method of claim 9 or 10, wherein the displacement and / or position estimation means comprise an inertial unit composed of one or more accelerometers and / or one or more gyroscopes.   The method of claim 9, 10 or 11, wherein the displacement and / or position estimating means comprises digital analog electronic converters measuring the power consumption of electric motors of the remotely operated vehicles. (1) to estimate their speed.   13. Method according to one of claims 9 to 12, wherein the means 5 for estimating the displacement and / or position comprises pressure sensors and in particular pitot tubes.   14. Method according to one of claims 9 to 13, wherein the displacement and / or position estimation means comprise a GPS receiver 10.   15. Method according to one of claims 9 to 14, wherein the tele-controlled vehicles (1) have a computer provided with filtering and data fusion algorithms, so as to estimate the most likely quantities to from the data from all the sensors.   16. The method of claim 9 in combination with claim 8, wherein the radio transmission is carried out in real time to transmit to all other remotely controlled vehicles (1) their displacement estimate and / or position.   17. The method of claim 16, wherein the radio transmission comprises an update of the displacement and / or position estimates at the same frequency as the coding of the video images, in particular 25 times per second.