轮辐结构压电式六维力传感器设计

Design of six-axis force piezoelectric sensor with spoke structure

针对机器人对工作环境进行反馈进而实现自动化作业,展开了对压电式六维力传感器的研究。本文选用压电石英作为力敏元件,结合并联分载原理及多点测量原理提出一种8点支撑轮辐式压电六维力传感器结构及其测量原理,它具备强解耦、轻量化、大量程和高固有频率的特点。利用ANSYS软件进行参数化建模,并进行六维力静力学仿真实验,验证了8点支撑轮辐式传感器测量原理。搭建了准静态标定及动态标定平台,对设计的压电式六维力传感器进行标定。实验结果表明,传感器的非线性度<0.5%,维间干扰<4%,固有频率超过6 kHz。轮辐式结构压电六维力传感器可以有效地完成六维力测量并消除维间耦合,满足动态测量需求,为轻量化大量程传感器的设计提供了理论基础和设计依据,对其他类型压电式六维力传感器设计和研制具有重要的参考价值。

Aiming at the robot's feedback to the working environment for realizing automatic operation,a piezoelectric six-axis force sensor was designed.Specifically,an eight-fulcrum spoke six-axis force sensor structure combined with the principle of multipoint measurement was proposed herein.Quartz was employed as the piezoelectric material in the force-sensing device.The advantage of such a sensor is its strong decoupling,light weight,large range,and high natural frequency.The parametric modeling of this sensor was carried out using the ANSYS finite element software.The measurement principle of the eight-fulcrum sensor’s feasibility was verified through a six-axis force quasi-static simulation.Moreover,a quasi-static and dynamic calibration experimental platform was built to conduct the calibration experiment.The experimental results show that for the proposed sensor,the nonlinearity is less than 0.5%,inter-dimensional interference is more than 4%,and natural frequency is over 6 kHz.From the theoretical analysis and experimental results,we confirmed that the sensor structure could complete the six-axis force measurement and that the coupling between the dimensions was eliminated.The demand for dynamic measurement was thus fulfilled.The proposed sensor’s structure provides the theoretical and design bases for the design of lightweight large range sensors,which is of important reference significance for the design and development of other types of piezoelectric six-axis force sensors.