Research Of Two-Degree-of-Freedom Probe Positioning System

Probe scaffold and control system which belong to equipment in the injection blowing tester of combustion turbine are used for probe locating in the laboratory. This probe locating system with all-digital control is suitable for two types of sensors, the hot-wire anemoscope and pressure probe at the same time, which has high locating precision of probe, multiple-point distributed measurement and automatic position of probe and so on.This paper analyzes the institution and character of locating system, and then completes integrated design. This system which is comprised of PC, CAN bus conversion interface, controller, and locating institution module with two-degree-of-freedom and so on employs the idea of building block design. Executor of angular displacement is in the form of circular tooth gear of zero clearance mesh. It employed with the lead-screw nut form of executive component makes probe locating system with two-degree-of-freedom move smoothly, with high locating precision. After the design of control module and position servo module based on LM629 is accomplished, it guarantees the motional reliability of the probe locating system. Compare the practical all kinds of buses and design the communication system, establish the first cell and scaffold of probe locating based on CAN232 module. Communication cell completes the mission which connects with the first PC. And it accepts position stated value and all kinds of command (such as, system reset, system self-check and so on). In response to the positional value, position control cell drives motor to the specified position, at the same time it feeds back practical motional value. CAN232 module extends RS232 communication distance of PC, elevates systematic capability of anti-interference. Furthermore, CAN bus which at most 128 locating institutions with two-degree-of-freedom are controlled synchronously by PC can carry out multiple-point communication.From the reality of system application, this paper exploits control software according to the probe locating system and has proceeded with the experimental research of the probe locating system. According to indexing of the design requirement, it accomplishes the experimental analysis of two-degree-of-freedom, which meets the demand for design.