An Experimental Study on the Design & Construction of a Torque Measurement Unit with Tactile Sensors

This paper presents the state of the art of the design and construction of a torque measurement unit based on a new modification in balancing method. This unit consists of six soft tactile sensors that each include a MEMS barometer covered by silicone rubber. Sensors are mounted in an array under the body of a servo motor to read the force from which motor torque can be obtained. Correct performance of sensor was validated in experimental tests by applying different loads on a Kinco servo motor and comparison of sensor output with value of actual torque obtained from motor driver software. The sensor was able to measure torque with less than 0.1 N.m uncertainty. The main advantage of this torque measurement method is its accuracy, simple construction, precision, real-time measurement and low cost compared to expensive strain gauge based sensors. Due to its soft surface, this torque sensor can be safely employed in human-robot interaction purposes and one can instantly find the force exerted on the environment by the end effector of robot due to the low delay time of the sensors.