光电编码器两种精码波形细分方法原理误差对比  

Comparison of the principle error between two fine code waveform interpolation methods of photoelectric encoders

作　　者：冯英翘[1,2] 万秋华[1] 宋超[1,2] 赵长海[1] 孙莹[1] 杨守旺[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033 [2]中国科学院大学,北京100049

出　　处：《红外与激光工程》2014年第7期2283-2288,共6页Infrared and Laser Engineering

基　　金：中国科学院知识创新领域前沿项目

摘　　要：光电编码器通常利用细分两路正交的码盘精码信号达到高分辨力的目的,为使细分技术更加完善,对基于三角波和基于正余弦波的两种细分方法进行了专题研究。分别对理想信号中存在直流误差、幅值误差、基波相位误差、高次谐波误差几种典型误差情况进行了分析,比较两种基于不同波形细分方法的抗干扰能力。实验对精码信号介于正余弦波和三角波之间的编码器进行测试,对于同一台编码器,采用正余弦波细分时精度为36″,采用三角波细分时精度为42″。结果表明:基于正余弦波的细分方法抗干扰能力优于基于三角波的细分方法。对于高精度光电编码器研制和生产时,可利用正余弦波对精码信号进行细分或将实际信号校正至标准正余弦波再细分。Interpolating two-channel orthogonal fine code signals is usually applied in the photoelectric encoders to get high resolving ability, and to better perfect the interpolation technique, special research was carried out on two interpolation methods which were based on triangular waveforms and sine-cosine waveforms. Analysis was implemented separately on ideal signals where several typical errors existed, including direct current drift, amplitude error, fundamental phase error and higher harmonic error, and anti-interference ability was compared between the two different waveform interpolation methods. The photoelectric encoder with fine code signal between sine-cosine waveform and triangular waveform was tested, and for the same encoder, the accuracy was 36″ when interpolated with sine-cosine waveforms, and 42″ with triangular waveforms. Results demonstrate that, the anti-interference ability of interpolation method based on sine-cosine waveforms is better than that based on triangular waveforms. When developing and manufacturing high-accuracy photoelectric encoders, it is suggested that sine-cosine waveforms should be used in the interpolation of fine code signal, or launch interpolation till the actual signal is calibrated to standard sine-cosine waveforms.

关 键 词：光电编码器 三角波细分 正余弦波细分 误差 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]