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The Acceleration/Deceleration Control Algorithm Based on Trapezoid-Curve Jerk in CNC MachiningKeywords: Machine tools impact , smooth control , step change , surface quality , trapezoid-curve jerk Abstract: In this study, we propose the acceleration/deceleration control algorithm based on trapezoid-curve jerk in CNC machining. In aviation and mould and die industry, it is much significant to achieve high accuracy CNC machining on complex profile parts. The unsmooth Acceleration/Deceleration (ab. Acc/Dec) control in feed movement is one of the main reasons to bring about machine tools impact and vibration in practical machining. After analyzing the CNC machine tools dynamic model, an Acc/Dec control algorithm based on trapezoid-curve jerk is put forward in order to avoid step change in jerk curve in the study; Moreover, the motion profile smooth control approach based on continuous jerk is developed in details to decrease machine tools impact according to various kinematics constraint conditions, such as the maximum acceleration, the maximum jerk, the machining program segment displacement, the instruction feedrate and so on; Finally, the developed Acc/Dec approach and the traditional linear Acc/Dec approach are compared in the CNC experimental table. The results reveal that the developed approach can achieve more smooth and flexible motion profile, which is helpful to minish machine tools impact and enhance parts machining surface quality.
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