Performance analysis of over-constrained orthogonal parallel six-axis force sensor

An over-constrained orthogonal parallel six-axis force sensor is an improvement over the traditional parallel six-axis force sensor and has the advantage of simple mapping relations. According to this improved configuration, performance parameters, such as decoupling characteristics, uniform-load characteristics, and range-limited characteristics, were used for performance analysis and were mathematically established. Then, the relation between the performance parameters and sensor design parameters was analysed numerically. Finally, a sensor prototype was designed and optimised into a second prototype based on the analysis of performance parameters. Results show that the vertical branch decoupling characteristic of the first and second prototypes were 19 % and 8.8 % full-scale (FS), respectively, and the range-limited characteristics of the first and second prototypes are 7.1 % in the Fz direction and 3.9 % FS, respectively. This shows that the proposed performance parameters can better analyse the performance of the over-constrained orthogonal parallel six-axis force sensor and optimise the sensor structure.