Measurement control system for multi-shaft supported air floatation platform

A measurement and control system for a multi-axis supported floatation platform, characterized in that, the system processes measurement and control of the multi-axis supported floatation platform, the multi-axis floatation platform comprises a load platform (1), M number of support legs (2), M number of floatation cylinders (3) and M number of gas bearings (4), where M is 3, 4, 5, 6, 7 or 8,

• the load platform (1) is a circular platform, the load platform (1) is supported by the M number of support legs (2), M number of connecting points are defined at the position where the M number of support legs (2) and a bottom surface of the load platform 1 are connected and form a regular M-polygon,
• each of the support leg (2) has one end connected to one floatation cylinder (3), each of the floatation cylinder (3) has a bottom end connected to one gas bearing (4) through floatation ball bearing,
• the measurement and control system comprises a load feedback unit (5), an execution unit (6), a position measurement unit (7), a safety unit (8), a control (9), a rotary motor (10) and a linear light source (11),
• the load feedback unit (5) comprises M number of pressure sensors (5-1) and four differential sensors (5-2);
• the execution unit (6) comprises M number of servo voice coil motors (6-1) and M number of servo voice coil motor drivers (6-2);
• the position measurement unit (7) comprises a plane grating (7-1), M number of linear gratings (7-2), a CCD linear array (7-3), an inclination sensor (7-4), M number of electronic levels (7-5) and an indoor GPS (7-6);
• the safety unit (8) comprises 2M number of proximity sensors (8-1) and M number of temperature sensors (8-2);
• the CCD linear array is formed by not less than six CCDs,
• the multi-axis floatation platform is arranged to position on a circular concrete base, all the CCDs of the CCD linear array (7-3) are positioned uniformly along the circumferential direction of the circular concrete base, the load platform (1) comprises a rotary motor (10), the rotary motor (10) has a top surface at which the linear light source (11) is positioned,
• each of the support leg (2) has an inner portion in which one pressure sensor (5-1), one servo voice coil motor (6-1) and one linear grating (7-2) are arranged, the pressure sensor (5-1) is arranged for measuring the torque of the corresponding support leg (2), the servo voice coil motor (6-1) is arranged for driving extension and retraction movement of the corresponding support leg (2), each of the servo voice coil motor (6-1) is driven by one servo voice coil motor driver (6-2), the linear grating (7-2) is arranged for collecting displacement amount information produced from driving the support leg (2) by the servo voice coil motor (6-1),
• the four differential sensors (5-2) are uniformly distributed along the circumferential direction of the load platform (1) on the outer edge of a top surface of the load platform (1), the differential sensors (5-2) are arranged for measuring the relative position between the load platform (1) and a load on the load platform (1),
• the plane grating (7-1) is installed on the top surface of the load platform (1), the plane grating (7-1) is arranged for measuring the relative displacement amount of the load on the load platform occurred at two relative perpendicular directions with respect to the load platform (1),
• the inclination sensor (7-4) and the M number of electronic levels (7-5) are mounted onto the top surface of the load platform (1), the inclination sensor (7-4) is arranged for measuring a vibration angle of the load platform (1) at an x-direction and an y-direction under a spatial coordination system in a process of movement, the M number of electronic levels (7-5) are corresponding to the positions of the M number of connecting points between the bottom surface of the load platform (1) and the M number of support legs (2), the electronic levels (7-5) are arranged for measuring the static state of the load platform (1),
• the indoor GPS (7-6) is mounted on an upper position relative to the circular concrete base and is arranged for measuring position coordinates of the load platform (1) on the circular concrete base,
• each of the support leg (2) has an upper displacement limit and a lower displacement limit of its inner portion and one proximity sensor (8-1) is provided at each of the position of the upper and the lower displacement limit respectively, the proximity sensor (8-1) is arranged for providing real-time position limit alert, each of the servo voice coil motor (6-1) comprises one temperature sensor (8-2) installed at its inner portion, the temperature sensor (8-2) is arranged for providing a real-time temperature alert,
• the pressure sensor (5-1) has a pressure signal output terminal connected to a pressure signal input terminal of the control (9), the differential sensor (5-2) has a position signal output terminal connected to a position signal input terminal of the control (9), the control 9 has an actuating control signal output terminal connected to an actuating control signal input terminal of the servo voice coil motor driver (6-2), the servo voice coil motor driver (6-2) has an actuating signal output terminal connected to the actuating signal input terminal of the servo voice coil motor (6-1), the servo voice coil motor (6-1) has an actuating signal output terminal connected to the actuating signal input terminal of the support leg (2),
• the plane grating (7-1) has a relative position displacement signal output terminal connected to a relative position displacement signal input terminal of the control (9), the linear grating (7-2) has a support leg position displacement signal output terminal connected to a support leg position displacement signal input terminal of the control (9), the CCD liner array (7-3) has a monitor signal output terminal connected to the monitor signal input terminal of the control (9), the inclination sensor (7-4) has an inclination signal output terminal connected to an inclination signal input terminal of the control (9), the electronic level (7-5) has a level signal output terminal connected to a level signal input terminal of the control (9), the indoor GPS (7-6) has a GPS signal output terminal connected to a GPS signal input terminal of the control (9),
• the temperature sensor (8-2) has a temperature signal output terminal connected to a temperature signal input terminal of the control (9), the proximity sensor (8-1) has a position limit signal output terminal connected to a position limit signal input terminal of the control (9).