Multi-blade grating control system based on field bus and high-speed differential serial communication

Abstract

The invention relates to a multi-blade grating control system based on field bus and high-speed differential serial communication, and belongs to the technical field of field control and data acquisition of medical equipment. The multi-blade grating control system comprises a general computer, a motion controller based on the field bus and a plurality of multi-shaft motor control units; wherein one end of the motion controller is connected with the general computer, the other end of motion controller is connected with the multi-shaft servo driver in each multi-shaft motor control unit respectively and synchronously through the field bus. In each multi-shaft motor control unit, the two ends of the driving motor are connected with the multi-shaft servo driver and a multi-channel signal collector respectively. The multi-channel signal collector is connected with the multi-shaft servo driver through a high-speed differential serial communication interface. The system can reduce the numberof the transmission cables, improve the manufacturability and reliability, when the number of the driving motors is large, and the data transmission amount is great. A multi-channel signal collector can complete the position acquisition and transmission of the multi-shaft motor in a current loop control period, so that the real-time performance requirements of the servo control are met.

Description

technical field [0001] The invention belongs to the technical field of on-site control and data acquisition of medical equipment, in particular to a multi-leaf grating control system based on field bus and high-speed differential serial communication. Background technique [0002] In radiation therapy, the key core component to realize intensity-modulated radiation therapy is the multi-leaf collimator (Multi-leaf Collimator, MLC). The multi-leaf collimator uses the tungsten alloy leaf array as the actuator and is driven by the multi-axis motor array. Each leaf moves to the corresponding position according to the position command issued by the multi-leaf collimator control system, and quickly and accurately forms the field shape required by the clinic. Each motor drives a blade, and the actual MLC requires multiple motors (80 or 120 in conventional products), so realizing high-speed, real-time and precise control of the motor array is an important issue in the multi-leaf enco...

AI Technical Summary

Problems solved by technology

However, judging from the development trend of MLC, the DC motor will be replaced by the AC servo motor (the position feedback of the AC motor has four signal lines), and the number of blades will also be doubled. Therefore, if the current parallel transmission scheme is still adopted, the signal line The number of cables will reach nearly 1000, which will greatly affect the system reliability

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