Information and Communication Engineering, School of Electronic and Information Engineering, Changchun University of Science and Technology, Changchun 130022, China.
Key Laboratory of Airborne Optical Imaging and Measurement, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China.
Sensors (Basel). 2022 Dec 6;22(23):9543. doi: 10.3390/s22239543.
The ball joint is a multi-degree-of-freedom transmission pair, if it can replace the inner frame in the aviation photoelectric pod to carry the optical load, which will greatly simplify the system structure of the photoelectric pod and reduce the space occupied by the inner frame. However, installation errors in ball joint siting introduce nonlinear errors that are difficult to correct and two degree of freedom angular displacement of the ball joint is difficult to detect, which limits application in the precision control of two degrees of freedom systems. Studies of spherical capacitive sensors to date have not tested sensors for use in an inner frame stabilisation mechanism nor have they analysed the influence of installation error on sensor output. A two-axis angular experimental device was designed to measure the performance of a ball joint capacitive sensor in a frame stabilisation mechanism in an aeronautical optoelectronic pod, and a mathematical model to compensate for ball joint capacitive sensor installation error was created and tested. The experimental results show that the resolution of the capacitive sensor was 0.02° in the operating range ±4°, the repeatability factor was 0.86%, and the pulse response time was 39 μs. The designed capacitive sensor has a simple structure, high measurement accuracy, and strong robustness, and it can be integrated into ball joint applications in the frames of aeronautical photoelectric pods.
球关节是一种多自由度的传动副，如果能够代替航空光电吊舱中的内框来承载光学负载，将大大简化光电吊舱的系统结构，减少内框占用的空间。但是，球关节安装误差会引入难以修正的非线性误差，且球关节的两自由度角位移难以检测，限制了其在两自由度系统精密控制中的应用。目前对于球形电容传感器的研究还没有测试过用于内框稳定机构的传感器，也没有分析安装误差对传感器输出的影响。设计了一种两轴角实验装置，用于测量航空光电吊舱中框架稳定机构中球关节电容传感器的性能，并建立和测试了一种用于补偿球关节电容传感器安装误差的数学模型。实验结果表明，在±4°的工作范围内，电容传感器的分辨率为 0.02°，重复性系数为 0.86%，脉冲响应时间为 39μs。设计的电容传感器结构简单，测量精度高，鲁棒性强，可集成到航空光电吊舱内框的球关节应用中。
