Optimization And Application Of Winding Machine Feed-rate Considering Acceleration Constraint

In the current CNC machining industry,there are more and more application scenarios of five-axis CNC machine tools.Due to the addition of two rotation axes,the five-axis machine tool has a nonlinear relationship between the movement of the tool point and the movement of each axis.At some special inflection points,the above-mentioned nonlinear characteristics may cause the single-axis command acceleration to break through the performance constraints of the machine tool servo,and cause the machine tool to alarm and stop.Due to the calculation real-time constraints of the CNC system,the CNC system generally uses the forward-looking method to obtain the N-segment G code information in front of the processing point,and performs speed planning based on the forward-looking local information.The number of forward-looking program segments is limited,and the actual speed planning cannot be complete.The orientation considers the characteristics of the global speed curve.Therefore,this forward-looking algorithm will cause the speed planning to split a long continuous acceleration and deceleration interval into multiple intervals,so that the machine tool does discontinuous acceleration and deceleration in an acceleration and deceleration interval,resulting in the machine tool.Processing vibration.This paper takes the CNC winding machine as an example,and proposes an offline prediction method for the command data of the CNC system in response to the command acceleration overrun in the winding machine following mode.In the offline environment,through the analysis of G code commands and machine tool motion constraints,you can predict the command trajectory of the CNC system in follow mode and the command speed curve of speed planning.This paper simulates the machining process in a discrete manner,calculates the axisspecific command acceleration of the CNC system,and analyzes the relationship between trajectory planning,command speed,and axis-by-axis acceleration,and proposes a way to increase the axis-by-axis command acceleration constraint in speed planning The method solves the problem that the follow mode slave axis command acceleration exceeds the limit.Aiming at the problem that the numerical control system caused discontinuous acceleration and deceleration in a large interval caused by the above-mentioned forwardlooking algorithm,this paper proposes a method to identify the continuous acceleration and deceleration speed planning interval,which can identify the acceleration and deceleration trend over a long distance,and Ignoring small speed disturbances,based on the results of the recognized speed interval,the CNC system is assisted in speed planning by means of i codes,so that the speed of the machine tool changes more smoothly in a large interval.Finally,in the experimental part,this article combined with the auxiliary code programming provided by the HNC8 system,designed and developed the G code offline optimization software,which implements the above-mentioned driven axis acceleration constraint method,and assists the CNC system in speed planning through i code.,Solve the problem that the acceleration of the driven shaft of the winding machine exceeds the limit and the vibration of the machine tool.