A Novel Approach for Detecting Rotational Angles of a Precision Spherical Joint Based on a Capacitive Sensor
A Novel Approach for Detecting Rotational Angles of a Precision Spherical Joint Based on a Capacitive Sensor
复制标题
基于电容传感器的精密球关节旋转角度检测新方法
DOI：
10.3390/mi10050280
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发表时间：
2019-05-01
期刊：
影响因子：
3.4
通讯作者：
Ju, Bingfeng
中科院分区：
文献类型：
--
作者：
Wang, Wen;Yang, He;Ju, Bingfeng
精密球形接头通常在许多工程应用中用作多自由度（DOF）机械铰链，例如，机器人和并联机械手。球铰转角的实时精确测量不仅有利于机械传动系统的实时闭环控制，而且对运动误差的预测和补偿具有重要意义。提出了一种基于电容传感器的球铰转角测量新方法。首先，分析了球铰的三自由度角运动。给出了该电容传感器的结构，推导了球铰转角和电容电容的数学模型。最后，利用Ansoft麦克斯韦软件对不同旋转角度下的电容值进行了仿真。仿真结果表明，电容器的仿真电容值与理论电容值的变化规律基本一致，验证了所提出的球铰转角电容检测方法的可行性和有效性。
Precision spherical joints are commonly employed as multiple degree-of-freedom (DOF) mechanical hinges in many engineering applications, e.g., robots and parallel manipulators. Real-time and precise measurement of the rotational angles of spherical joints is not only beneficial to the real-time and closed-loop control of mechanical transmission systems, but also is of great significance in the prediction and compensation of their motion errors. This work presents a novel approach for rotational angle measurement of spherical joints with a capacitive sensor. First, the 3-DOF angular motions of a spherical joint were analyzed. Then, the structure of the proposed capacitive sensor was presented, and the mathematical model for the rotational angles of a spherical joint and the capacitance of the capacitors was deduced. Finally, the capacitance values of the capacitors at different rotations were simulated using Ansoft Maxwell software. The simulation results show that the variation in the simulated capacitance values of the capacitors is similar to that of the theoretical values, suggesting the feasibility and effectiveness of the proposed capacitive detection method for rotational angles of spherical joints.