Application of 6-Axis Force Torque (F/T) Sensor for a Three Fingered Robot Hand Impedance Control

In previous work, a position-based force control was established using two-axis load cell buttons embedded into a 7-DOF three-fingered robot hand. However, the inconsistent readings of the incurred force which is due to the loose placement of the movable parts of the fingertip has led to the motivation to replace the sensor. This paper discusses the application of a new 6-axis force sensor for the robot hand impedance control. The objectives of this work are to establish a new interface and to modify the existing impedance control of the robot hand according to the application of the new 6-axis FT sensor and interfaces. The interface between the hardware, sensors, and controller within the robot system was implemented on the Simulink Matlab application. The inputs and outputs of two different Peripheral Component Interconnect (PCI), which are PCI NI-6225 and PCI ADVANTECH-1771 were configured and verified through experiment. It can be observed that the new interface was feasible by using multiple PCIs. Meanwhile, the impedance control results showed that the position reference changed accordingly when the exerted force exceeds the threshold force based on the measurement from the new sensor.