垫圈式压电六维力传感器静态灵敏度解析

Static sensitivity analysis of washer-type piezoelectric six-axis force sensor

为实现基于垫圈式压电六维力传感器灵敏度指标的多结构参数设计与优选,必须开展传感器的静态灵敏度解析数学模型研究。首先,分析了传感器的结构特点和工作原理,根据载荷在传感器内部的传递路径推导其静态灵敏度解析数学模型;然后,使用解析数学模型和基于ANSYS软件的数值模型对9组不同结构参数模型分别进行了解析计算和数值模拟,在运用统计学理论对两种方法得到的结论进行分析的基础上,验证了解析数学模型的有效性;最后,引入正交试验,结合解析数学模型研究了多个结构参数对传感器灵敏度的影响规律,优选了传感器结构参数并研制了实验样机,完成了静态灵敏度标定实验。研究结果表明:垫圈式压电六维力传感器的解析数学模型与数值模型之间的综合相关系数为0.988;实验原型相对于解析数学模型和数值模型的平均载荷传递系数分别为0.73和0.75;解析数学模型、数值模型和实验原型的综合各向同性度分别为0.71,0.71和0.67,3种模型对传感器的灵敏度研究结论一致。以解析数学模型为基础的正交试验可实现对该类传感器的多参数主动设计和优选。

To achieve a multi-structure parameter design and optimization based on the sensitivity index of a washer-type piezoelectric six-axis force sensor, an analytical mathematical model of the static sensitivity of the sensor must be studied. First, the structural characteristics and working principle of the sensor are analyzed, and a static sensitivity analytical mathematical model is derived based on the load transfer path inside the sensor. Then, an analytical mathematical model and a mathematical model based on ANSYS software are used to conduct analytical calculations and a numerical simulation for nine structural parameter models, respectively. Based on an analysis of results obtained from the two methods using statistical theory, the effectiveness of the analytical mathematical model was verified. An orthogonal experiment was conducted, and the influence rule of multiple structural parameters on sensor sensitivity was examined by combining the analytical mathematical models. Finally, the structural parameters of the sensor were optimized, an experimental prototype was developed, and a static sensitivity calibration experiment was conducted. Results show that the comprehensive correlation coefficient between the analytical mathematical and numerical models of the washer-type piezoelectric six-axis force sensor was 0.988. The average load transfer coefficients of the experimental prototype were 0.73 and 0.75 for the analytical mathematical and numerical models, respectively. The synthetic isotropy of the analytical mathematical model, numerical model, and experimental prototype was 0.71, 0.71, and 0.67, respectively, and the results of the sensitivity study of the three models were consistent. The study thus showed that an orthogonal experiment based on an analytical mathematical model could realize an active multi-structure parameter design and optimization of a washer-type piezoelectric six-axis force sensor.