作者：吴常铖1,2, 杨德华2, 曹青青3, 费飞2, 宋天赐2
作者单位：1. 东南大学仪器科学与工程学院，江苏 南京 210096;
2. 南京航空航天大学自动化学院，江苏 南京 211106;
3. 南京工业职业技术大学航空工程学院，江苏 南京 210023
关键词：视觉;最大长度序列;旋转角度
摘要：
针对现有基于视觉的旋转角度测量方法需要在物体旋转轴线方向放置摄像头来获取图像的问题，提出一种基于单目视觉和最大长度序列的旋转角度测量系统。该系统利用摄像头从侧面拍摄柱状旋转体周向的靶标图像实现角位移的测量。首先，该文在介绍最大长度序列的基础上详细描述基于视觉和最大长度序列的平面位移测量方法，包括图像处理、相位检测、序列检测、位移计算等部分。其次，采用双靶标构建0°~360°旋转角度测量系统，提出基于图像拉伸变换的角位移计算方法实现物体旋转角度的测量。最后，为验证系统的有效性进行标定实验及静态特性测试实验。结果表明：在0°~360°测量范围内，设计的角度测量系统非线性误差为0.027%FS，迟滞误差为0.048%FS，重复性误差为0.016%FS，总误差为0.057%FS，分辨率优于0.1°。
Rotation angle measurement system based on visual and maximum length sequence
WU Changcheng1,2, YANG Dehua2, CAO Qingqing3, FEI Fei2, SONG Tianci2
1. School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China;
2. College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China;
3. School of Aviation Engineering, Nanjing Vocational University of Industry Technology, Nanjing 210023, China
Abstract: Aiming at the problem that vision-based rotation angle measurement method requires placing a camera in the direction of the object's axis of rotation to obtain the image, a rotation angle measurement system based on vision and maximum length sequence is proposed in this paper. The measurement of the rotation angle is realized by pasting a target on the surface of the rotation body and capturing the target's image through a camera. Firstly, based on the introduction of the maximum length sequence, the method of displacement measurement based on vision and maximum length sequence, mainly including image processing, phase detection, sequence detection, displacement calculation are described in detail. Secondly, the 0° -360° rotation angle measurement system is constructed by using dual targets, and a method of calculating angular displacement based on image stretching transformation is proposed to measure the rotation angle of objects. Finally, experiments are carried out to verify the effectiveness of the system. The experimental results show that the designed angle measurement system has a nonlinear error of 0.027%FS, a hysteresis error of 0.048%FS, a repeatability error of 0.016%FS, a comprehensive precision of 0.057%FS and a resolution better than 0.1° within the measurement range of 0° to 360°.
Keywords: visual;maximum length sequence;rotation angle
2022, 48(1):122-128 收稿日期: 2020-11-23;收到修改稿日期: 2021-02-04
基金项目: 国家自然科学基金项目(61803201，U1931126)；江苏省自然科学基金项目(BK20170803)；中国博士后科学基金项目(2019M661686)；南京工业职业技术大学引进人才科研启动基金项目(YK18-03-05)
作者简介: 吴常铖（1987-），男，福建连城县人，副教授，博士，研究方为机器人传感与控制技术
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