Design And Development Of The Control System For Linear Accelerator Couch

The couch control system for Linear Accelerator is developed in this project.And the control object is the couch of O-Max Linear Accelerator equipment in Guangdong SPACO Company.In the thesis,the design requirements and the funcitions are analyzed in detail, and the design of the system, including hardware design and software design, is expatiated clearly.The control object of the system is the couch of Linear Accelerator equipment, and the purpose of the system is to realize the motion control and detecting function for the couch lengthways movement and vertical movement.This two motions are driven by DC servo motor.The couch has two control modes:including local manual operation and upper-computer remote operation.The control system composed of control module, drive module and upper-computer.The control unit is designed with AVR series MCU as the control core.The DC servo motor is controlled in PWM way.The PID control algorithms is used in close-loop speed control, and the system has good dynamic and static performance. The system use A/D converter measuring voltage in detecting motor speed and position of the couch.To lower the interference between power module and control core,the control part and the power part are displaced on different boards.The system hardware includes main motion control module and motor driver module.Main control module is the key part, including MCU control core, voltage signal detection circuit,power circuit, serial communication circuit and the periphery circuit.Motor driver module is connected directly with the two motors, including low-power driver circuit, over-current protection circuit and high-power H bridge driver circuit.The software design of the system including two parts:the remote operation software in upper-computer and the MCU firmware. The upper-computer is the equipment that realize man-machine conversation.The users can remotely operate the couch and monitor status of the couch by using operation software in the upper computer.The AVR MCU firmware is designed by C language and compiled by ICCAVR compiler.And modularize design is used to enhance the readability and facility of transplant.The main modules include the main program, PID control algolithm, serial communication, voltage signal detecting, PWM control and motion control.