LAMOST双回转光纤定位单元的零定位装置

LAMOST（Large Area Multi-Object Fiber Spectroscope Telescope)双回转光纤定位单元，为了提高单元的运动精度和可靠性，应设计一个绝对零位作为基准起点，每次定位运动可以从零位出发，减小累积误差，简化控制方案，还可在定位单元运转异常时，作为RESET的复位基准。在此介绍的接触式电零位检测系统，结构简单，控制方便且可靠性好，经实验表明其复杂精度高，大大减小了连续多次运行带来的累积误差，LAMOST光纤定位单元有了零位检测系统，就有了光纤位置的绝对零点，从而简化了控制方案，提高了系统的可靠性。

The zero positioning device of double revolving optical fiber positioning unit for LAMOST

It is necessary to design a scheme which takes an absolute zero position as the datum starting point and it could start from zero position for every positioning movement to reducing accumulative error and simplifying the control for the sake of enhancing motion accuracy and reliability of double revolving optical fiber positioning unit in LAMOST (Large Area Multi-Object Fiber Spectroscopic Telescope).It could also be regarded as a resetting datum of RESET while the positioning unit was running abnormaly.The contacting typed zero potential detection system being introduced here has a simple construction,convenient control and nice reliability.Through unit test indicates that it is high in repeat accuracy and greatly reduces the accumulative error brought about by continuous time and again operation.Whenever the optical fiber positional unit of LAMOST possesses zero position detection system,it will gain the absolute zero point for the position of optical fiber,thus simplified the control system and raised the reliability of the system.