Haptics force feedback based on current control loop for remote manipulation

This paper presents the development of a force control loop in a teleoperation system with master and slave robotic devices. The force control based on current control loop has been applied to a teleoperation open platform consisting on electric master device, hydraulic slave robot and equipment for data acquisition and control programming. This force control loop is applied in each master joint using a custom designed electronic board with current sensors for closing the control loop. This board gives information about the current consumption and the direction of rotation of each motor drive. For maintaining the correct relationship between current and torque in each motor some experiments were performed to obtain the curves with an force/torque sensor from ATI. Finally, an inexpensive force control is obtained in the master device, providing an accurate haptic feedback for the operator.