Two-Axis Turntable Servo System Design

Based on the research of a THAT two-axis turntable's control system, a set of hardware and software is designed. In the hardware we designed an interface circuit,A/D switching circuit,D/A switching circuit and a local circuit board, debugged the angular measuring system construct of rotary transformer and inductosyn and the whole turntable's control system. The software includes the control program, the angular measuring program and the interface program of computer programmed with VC language. The debugging result testified that our system absolutely reached the norms of system performance presented by client.In turntable's control system design, classical control method is still widely used. A double loop control system is designed in this paper. The main idea is: when the position error is large, coarse position control is effective to approach the given position quickly; when the position error is small, fine position control is effective to guarantee the control accuracy.By the debugging and analysis of turntable's system, we can conclude that the difficulty of designing a turntable's control system is still in the angular measuring system and the precision of the angular measuring system will directly influence the whole system's accuracy especially in the high accuracy system. But the method of double channels angular measurement in this paper is available, which its coarse channel can meet the precision of the coarse measurement and make the circuit easy and its fine channel adopts the method of bidirectional exciting and distinguishing from phase to measure the angular that can effectively guarantee the measuring accuracy, especially when we desire the whole system in high accuracy. The practice has approved that this method is available.