FORCE CONTROL SYSTEM USING PULSE DENSITY MODULATED SIGNAL

摘要

PURPOSE:To operate a system at a high speed by comparing a command input to the control system due to a PDM signal and the output of a force sensor outputted as a PDM signal with each other by a PDM operator and using a PDM signal correspondig to the pulse density difference as a motor command input. CONSTITUTION:The resistance of a pressure-sensitive conductive rubber 6 is changed in accordance with an applied force. Since this resistance is used as the time constant resistance of an oscillator, the output frequency of the oscillator is a function of the external force. The oscillator consists of amplifiers 7 and 8 and an RS flip-flop 9. Theis force sensor 13 is combined with a manipulator 12 and a motor 11. That is, the magnitude of the force to be displayed is set preliminarily to the manipulator 12 and is used as a command input 17 to a PDM (pulse density modulation) computing element 14. At this time, the magnitude of the force which the manipulator 12 displays is converted to a PDM signal by the force sensor 13 and is transmitted to the computing element 14. The PDM signal corresponding to the difference between a reference frequency and the frequency of the sensor output is generated in the PDM computing element 14 and is inputted to the motor 11 through a driver 18.