Ｓｔｅｗａｒｔ 六维力传感器寿命特性的诊断与优化

Low service life is one of the drawbacks of the Stewart six-axis force(SSAF)sensor that restricts the application of the sensor during the long-life in orbit operation of space station. Aiming at this problem,the test-based diagnosis analyses for the service life of the sensor are proposed. Based on the principle of measurement and the theory of nominal stress fatigue life,the relationship between the structural parameters of the sensor and its life characteristics is derived. Evaluation index and judgment criterion are given with the analyses of the first-order impact coefficient matrix. By applying the multi-objective optimization, optimal structural parameters and the objective function for the life characters of the sensor are obtained. The results of comprehensive index calculation,simulation and test show that structural stress equalization can be achieved with the life-character-based optimization method for structural parameters of the sensor. The influence of fatigue stress damage is significantly reduced as stress concentration is relieved,which effectively extends the service life the SSAF sensor.