Coordinate Control Algorithm Of Multi-axis For Multi-processor Architecture

Multi-axis motion control process will generate a tracking error,contour error,the error of the tool direction and synchronization errors.In order to reduce these errors,the synchronized coordination control algorithm,the contour error calculation method and the cross-coupling control strategy are researched.Firstly,a new synchronization controller is proposed to achieve synchronization error control.The new controller uses synchronization grating to measure the synchronization error directly.And a cross-coupling controller that is based on T-N coordinate is adopted to control the contour error and tangential error.Secondly,the identifying of motion control system for single axis,a position controller of single-axis and a coordination control system for multi-axis are modeled.Through simulating,the parameters tuning for PID control,feed forward control and adaptive sliding mode control for single-axis position controller are realized.The parameters tuning for the new synchronization controller and the cross-coupling controller based on T-N coordinate are also acquired by simulation.Finally,modular and hierarchical design idears have been used to design the architecture of multi-axis coordinate control system with single-processor,the architecture of multi-axis coordinate control system with multi-processor is proposed.The experiment platform of multi-axis coordinate control system with single-processor is set up.The erperiment of X-Y coordinate control are carried out on this platform.Here,the experimental platform of multi-axis coordinate control system with multi-processor is also set up for implementing the linear synchronous coordinate control experiment.These results indicate that:(1)The composite position controller is adopted which is composed of the adaptive sliding mode control and feed forward control.The experiments are carried out with the two different feedrate conditions:the federate is set 10mm/s and 20mm/s.When the cross-coupling controller of T-N based coordinate system is added to the multi-axis coordinate control system with single-processor,thecontour errors RMS of circular trajectory are reduced to 34.48%and 41.58%,and the contour errors RMS of NURBS trajectory are redued to 37.34%and 38.95%,respectively.When the new synchronization controller is applied to the multi-axis coordinate control system with multi-processor,the synchronization errors RMS will reduce 63.95%and 55.47%,respectively.(2)Using the architecture of multi-processor for multi-axis coordination can solve the problem of insufficient resources of single-processor.Compared with multi-axis are controlled by a processor,the motion control of a one-axis is relized by a processor can significantly reduce the processor periodic real-time task execution time and improve the control performance of multi-axis coordination.