Control method for cooperative work of multi-blade collimator blades based on cross coupling

Abstract

The invention discloses a control method for cooperative work of multi-blade collimator blades based on cross coupling. The control method comprises the following steps: S1, establishing a mathematical model of a single blade driving motor; S2, establishing a model of a transmission mechanism between the driving motor and blades; S3, designing a single blade position controller, and optimizing parameters, namely, by using a fractional order PID (Proportion Integration Differentiation) controller, optimizing parameters of the fractional order PID controller by using a particle swarm algorithm; S4, achieving cooperative control of multiple blades by using a cross coupling control method; S5, optimizing parameters of a cross coupling controller. Cooperative control of multiple blades is achieved by using the cross coupling control algorithm, on the basis that single blade in-place precision is achieved, contact friction caused by structural design, of the blades, is considered, then the blades are prevented from deviation in placement, the deviation is made up by using the cross coupling controller, cooperative work of the multiple blades with different given inputs is achieved, and the placement precision of the blades can be improved.

Description

technical field [0001] The invention relates to a multi-motor synchronous control technology, in particular to a method for controlling the blades of a multi-leaf collimator to work together by using a cross-coupling algorithm. Background technique [0002] With the continuous in-depth research of radiation therapy technology by scholars and institutions at home and abroad, the radiation therapy device has also made great progress. In the process of radiation therapy, the precise positioning and dose correction of the target area of ​​the lesion by the radiation therapy device are particularly critical. The main function of the Multi-leaf Collimator (MLC) is to achieve conformal radiation therapy, that is, by changing the The position of the blades of the grating makes the shape of the opening similar to the shape of the target area of ​​the lesion, thereby realizing conformal radiation therapy. Therefore, the research on the position precision control of the blades of mult...

AI Technical Summary

Problems solved by technology

[0004] Because the blades of the multi-leaf collimator (multi-leaf collimator) are discharged in pairs, in order to avoid the leakage of rays from each row of blades, the blades are engaged by grooves; therefore, there must be mechanical friction between the blades, and mechanical friction will inevitably make The positioning accuracy of each blade deviates

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