Design and static calibration of a six-dimensional force/torque sensor for minimally invasive surgery

Introduction: The use of surgery robotics is getting more and more important worldwide. In the present study, we propose a novel small-size six-dimensional force/torque sensor with the structure of double cross beams. This technology can be applied in robotic tele-operation systems used in minimally invasive surgery (MIS) robotic systems. Material and methods: The proposed sensor is made of duralumin which totally meets the stiffness requirement. The output voltage of the sensor will alter with the deformation of the elastic body and strain gauges. The feasibility was discussed by finite element analysis (FEA) and the coupling coefficient matrix was established with dimension reduced according to FEA. In addition, we designed a calibration platform and completed static calibration for the sensor. The methods and principles of measurements and data analysis were provided. Results: The calibration curves and coupling coefficient matrix were acquired by using the least squares method (LSM). Conclusion: Experimental tests and calibration error analysis showed that the proposed sensor has high accuracy, appropriate range, and played a role in promoting the application of force feedback technology in MIS.