一种用于检测球形接头微间隙的改进型电容式传感器。

An Improved Capacitive Sensor for Detecting the Micro-Clearance of Spherical Joints.

作者信息

Wang Wen, Qiu Wenjun, Yang He, Wu Haimei, Shi Guang, Chen Zhanfeng, Lu Keqing, Xiang Kui, Ju Bingfeng

机构信息

School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou 310018, China.

School of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China.

出版信息

Sensors (Basel). 2019 Jun 14;19(12):2694. doi: 10.3390/s19122694.

DOI:10.3390/s19122694

PMID:31207984

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6630451/

Abstract

Due to the flexible and compact structures, spherical joints are widely used in parallel manipulators and industrial robots. Real-time detection of the clearance between the ball and the socket in spherical joints is beneficial to compensate motion errors of mechanical systems and improve their transmission accuracy. This work proposes an improved capacitive sensor for detecting the micro-clearance of spherical joints. First, the structure of the capacitive sensor is proposed. Then, the mathematical model for the differential capacitance of the sensor and the eccentric micro-displacement of the ball is deduced. Finally, the capacitance values of the capacitive sensor are simulated with Ansoft Maxwell. The simulated values of the differential capacitances at different eccentric displacements agree well with the theoretical ones, indicating the feasibility of the proposed detection method. In addition, the simulated results show that the proposed capacitive sensor could effectively reduce the capacitive fringe effect, improving the measurement accuracy.

摘要

由于具有灵活紧凑的结构，球形关节在并联机器人和工业机器人中得到了广泛应用。实时检测球形关节中球与座之间的间隙，有利于补偿机械系统的运动误差并提高其传动精度。本文提出了一种用于检测球形关节微间隙的改进型电容式传感器。首先，提出了电容式传感器的结构。然后，推导了传感器的差分电容与球的偏心微位移的数学模型。最后，利用Ansoft Maxwell对电容式传感器的电容值进行了仿真。不同偏心位移下差分电容的仿真值与理论值吻合良好，表明了所提检测方法的可行性。此外，仿真结果表明，所提电容式传感器能够有效降低电容边缘效应，提高测量精度。