Design of a new current sensing device for joint torque force control of the precision assembly robot

A new set of current sensing device is designed used for a precision assembly robot´s joint motor´s current feedback in order to improve the output torque´s feature of the joint motor. It uses Hall current sensor to sense the current, modulates the simulated voltage into the PWM (Pulse Width Modulating) wave for anti jamming translation, counts the wave form with an ISA card and reads the wave in real-time by the control IPC. So the joint motor´s current closed loop of the robot is found. The subsequent calibration experiment depicts the device´s feature and works out the fitting curve´s equation of the calibration points. The sensing device has the advantage of simple structure, low cost, and good anti-disturbance feature.