The system mainly consists of 21bit all quantity encoder feedback, digital PID computation and DC servo mechanism.

该系统主要由21位全量编码反馈、数字PID运算和直流伺服机构组成。

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In the inner closed loop, general PID control method based on encoder feedback of motor is adopted, and in the outer closed loop, a new fuzzy control based on position feedback of joint is adopted.

利用电机码盘反馈构成内位置环控制，采用一般的PID控制律；通过关节位置反馈形成外位置环控制，采用模糊控制算法。

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There was also a feedback system, denying the encoder rat an extra reward if the decoder rat did not press the correct lever.

BBC: One rat brain 'talks' to another using electronic link