Stiffness analysis and parameter optimization of six-dimensional force sensor with the novel circular flexible spherical joint

Abstract

As robot haptic provider, six-dimensional force sensors are an indispensable component of industrial intelligence. To address the disadvantages of the existing six-dimensional force sensor, a novel circular flexible spherical joint is proposed, its stiffness model is derived by numerical analysis method and microelement, and the stiffness model of the circular flexible spherical joint is verified by finite element simulation. A parallel six-dimensional force sensor is designed based on a circular flexible spherical joint, and a mathematical model of the sensor was established. Based on the genetic algorithm, the structural optimization design of the circular flexible spherical joint was performed, and the structural parameters of the circular flexible spherical joints are obtained by analyzing isotropy. Finally, according to the optimization results, a sensor was developed and calibration experiments were carried out. The experimental results show that the maximum error of the sensor is 1.85%, which verifies the effectiveness of the mathematical model of the sensor, which has high measurement accuracy and can accurately measure the six-dimensional external force and moment applied to the sensor.