With the increasing popularity of automotive intelligence, auto companies are paying more attention to the layout of intelligent network technology. The author summarizes the intelligent development ideas of 10 key enterprises in China and the development of intelligent network technology in 2015. The reader has an overall understanding of the development of China's current intelligent networked cars. Incremental Encoder is commonly used, and Absolute Encoder is used if there are strict requirements on position and zero position. Servo system should be analyzed in detail, depending on the application situation. Commonly used incremental encoder for speed measurement, which can be used for infinite accumulation measurement; Absolute encoder is used for position measurement, and the position is unique (single or multiple turns). Finally, it depends on the application situation and the purpose and requirements to be realized. Incremental Linear Encoders,Linear Optical Encoder,Linear Position Encoder,Encoder Bearing Tester Yuheng Optics Co., Ltd.(Changchun) , https://www.yuhengcoder.com