the game , as shown in the figures , comprises a table 1 upon which a certain number of players 2 can move and a series of control devices 3 on each side , each control device 3 comprising a lever automatically returned to a neutral position in which that lever is not effective . in a forward tilted position , the lever commands movement of the player 2 in one direction and , when tilted in the opposite direction , it commands movement in the opposite direction , intermediate positions allowing pivoting of the player toward the right and toward the left . the table comprises an upper tabletop 4 and a lower tabletop 6 , these tabletops being strictly parallel , the tabletop 4 having an upper surface 7 consisting , for example , of a non - tearing mat on which the players and a ball 11 can move , a framework 8 having to withstand thermal and mechanical stresses , and insulator 9 and a conductive surface 10 formed from strips of metallized carbon or a conductive copper mesh , for example . the lower tabletop 6 is formed from a framework 12 on which rest an insulator 13 and a conductive surface 14 of the same type as the surface 10 . each player stands on a base 16 adapted to slide freely over the upper surface 7 , a permanent magnet 17 fixed under the lower surface of the base being mounted in such a way as to be slightly separated from the upper surface 7 . carriages 20 between the two tabletops 4 and 6 each correspond to a player . each carriage 20 comprises a lower compartment 21 and an upper compartment 22 . compartment 21 houses two direct current motors 22 and 23 , the output shaft 24 of the motor 22 driving , via a reduction gear system 25 , a wheel 26 running on the tabletop 6 . the output shaft 29 of the motor 23 drives , via a reduction gear system 27 , a wheel 28 . fig4 is a block diagram showing the control system for the motors 22 and 23 . the control devices comprise two potentiometers whose levers drive sliders ( see fig6 ). the voltages present at the analog port , during the excursion of the lever , define three zones , namely an intermediate rest zone between a forward movement zone and a reverse movement zone . three zones are also defined by the second potentiometer , namely a rest zone between a zone of pivoting toward the right and a zone pivoting toward the left . the generation of these voltages is simulated by the use of two comparators . the analog voltage is compared simultaneously with a high reference voltage , vrefh and with a low reference voltage vrefb . the output values of these comparators are the bits which determine the direction of rotation of the motors . the position of the contacts of two relays 32 and 33 define this direction of rotation . these relays control the switching on of the direct current motors 22 and 23 housed in the compartment 21 . the lever 3 is connected to a transmitting pic micro - controller 58 . the parallel inputs receive the four motor rotation bits ; two inputs of the analog - digital converter in the micro - controller receive the two analog signals from the two potentiometers . the carriage 20 is supported by balls 35 which co - operate with the lower surface of the tabletop 4 and balls 36 which bear against the upper surface of the tabletop 6 in such a way that the carriage can move freely in all directions . the balls 35 and 36 are made of an insulating plastics material . the compartment 22 supports a permanent magnet 38 which is maintained slightly separated from the lower surface of the tabletop 4 . the compartment 22 contains stacked electronic cards 40 interconnected by connecting bars 41 . these cards are powered by a stabilized power supply . the conductive surface 10 of the upper tabletop 4 is powered by a 12 v stabilized power supply , the carriage 20 supporting sliding contacts 33 which co - operate with the conductive surface , and the voltage at the conductive surface 14 is 0 v , the sliding contacts 44 picking up the power supply current which feeds all of the cards 40 through corresponding conductors , the current returning via the conductive surface 14 and sliding contacts 45 . each control lever 2 is housed in a casing 50 which contains the transmission electronics . the control can be proportional or discrete . as can be seen in the diagram in fig5 each lever 3 is associated with a transmitting micro - controller 58 preferably connected to a philips bus i 2c line or to any other pc - compatible computer network , network control micro - controllers 60 transmitting commands to modems 66 of the carriages 20 which comprise receiving micro - controllers 62 , these systems being powered by power supplies 61 . each transmitting micro - controller 58 sends commands depending on the position of the lever 3 to the carriage 20 which contains the receiver . parallel ports of risc architecture pic micro - controllers 55 ( see fig4 ) constitute a small local network which the network control micro - controllers 60 uses to communicate with the pic micro - controllers transmitting command messages related to the position of the levers 3 and to transmit these commands to a modem 56 . the voltage at the output of a converter is coded in four bits . the transmitting pic will establish contact with a network controller which tells it the receiver it wishes to reach and sends it the commands it wishes to send to this receiver . a philips bus i 2c line or any other pc - compatible computer network ( see fig5 ) enables bidirectional dialog on only two wires . it is a serial mode bus . as the transmitting micro - controllers 58 do not have a serial interface , one input line and one parallel output line provide this function , using the timer as a transmission clock . speeds of 9 600 bauds can be achieved in this way . the messages are sent with redundancy or repetition and error checking . this precaution is necessary considering the choice of power supply mode for the receivers , the high probability of interference related to the system of sliding contacts collecting the power supply current , and the rotation of the small motors . it is thus possible to connect different elements to the bus : all that is required is to connect each parallel output to two wires . a protocol is used which assures efficient sharing of the communication facility . an eeprom is used to program the data and its processing . the power supply voltage must be the same for all of the components . the outputs are open - collector outputs ( or open - drain outputs in the case of cmos circuits ), and the resultant level on the line is therefore the result of applying an and function of all of the connected outputs . because of the vcc supply pull - up resistors , the sda signals ( data and address signal ) and the scl signals ( clock signals ) and at 1 is all the outputs are at 1 . these signals are read continuously without risk of interfering with the line level . after accepting the transmission request from a transmitting micro - controller 58 , the network controller 60 searches its memory for the address of the sought receiver , associates it with the motor rotation and speed of rotation commands , and stores everything . for 100 % of the time , it stores such information sent by the elements of the system it controls . for 50 % of the time , it sends the stored information to the receivers via a modulating modem 56 . the rate of this serial transmission is faster than that of serial transmissions by the system . the digital data is carried by the power supply over the entire surface of the table . in order to optimize the path of the current , the power supply is over - rated . the modulation used is either ask ( amplitude modulation if the ne5050 is chosen or fsk ( frequency modulation ). fig6 is a diagram showing the connection between the levers 3 and the transmitting micro - controllers 58 . the carriage 20 is preferably made of aluminum and comprises , on its side surface , a layer of elastic foam 65 to damp impacts between carriages . at the receiving end , the modem 56 , in its receiving mode , demodulates the received signal . as computer data is sensitive , since on piece of interference is all that is necessary to falsify the message , the modem is capable of eliminating noise and interference from the power supply . the digital message is then analyzed by the associated pic micro - controller . the address received is compared with the receiver &# 39 ; s own address , which is unique . the message is received several times and is subjected to error checking . if all of these checks are correct , the micro - controller 55 processes the commands , allocating them either to power outputs controlling relays or to the generation of a squarewave signal , simulating pwm control . in general terms , there are two independent systems of transmitters , one for each team , each having their network controller and a transmitting modem . a dedicated bidirectional line can be provided between the two controllers alternatively carrying stop transmission commands for 50 % of the time . communication is therefor shared equally between the two teams . management of communication is independent within each team . a card 40 carries darlington bridges , or any other variable speed drive , which control the speed of the motors 22 and 23 . this card also carries relays controlling the switching on of the motors . in this way , a lever 3 controls the movement of a player 2 in all directions , that is to say slow or fast forward movement , slow or fast reverse movement and pivoting to the right or to the left . the base 16 is preferably octagonal to allow better control of the ball 11 and the fast forward control simulates kicking the ball . the invention is not limited to the embodiment which has just been described and shown , of course . numerous modifications can be applied to it without departing from the scope of the invention .
a game , of the table soccer type , comprises a playing surface , pieces imitating players and a ball simulating a football . it has , along the table , on each of two opposite sides , a series of control levers , each lever corresponding to the movement of a player . each player is connected to a carriage comprising two drive motors , each of which drives a wheel , and an electronic receiving unit . each control lever is attached to a transmitter unit in order to control selectively the power supply of one or other of the motors in one direction or the other .