Compensation of backlash for teleoperated geared motor drive systems

Robotics is a major field that is being researched for decades. With the use of robotic technology, applications of the microscopic level to the places where the human cannot reach are facilitated. When it comes to the larger robots, large actuators and drives have to be used to obtain the desired amount of power and the force or torque needed. As the electric motors have a limitation of torque output with its capacity, the most desirable way is to use the gears. However this introduces large inertia, backlash and friction to the system. If the system is used for the transmission of haptic information in bilaterally controlled systems, it greatly deteriorates the performance of the system and necessitates a compensation for the backlash caused by the gears. This paper introduces a method to compensate the backlash generated by the geared system. This method uses two identical counter operating drives per joint to compensate the backlash effect. Experiments are carried out for the proposed method to validate its accuracy.