摘要
加减速控制是数控系统的关键技术之一,影响着零件加工时的高效性和平稳性,同时由于传统数控系统在加工复杂的曲线曲面时,需要生成的大量连续微线段,这不仅增加了数控系统的负担,且在拐角处仅G0连续,导致在拐角处频繁加减速和机床振动,降低零件加工效率和加工质量.两步法拐角过渡是先进行轨迹光顺再进行速度规划,不仅步骤繁琐,而且降低了加工效率.因此,针对传统三角函数中最大加加速度只存在峰值导致加工效率降低的问题,本文先对加减速连续性较好的传统三角函数加减速控制算法进行改进,以sin^(2)x作为加加速度的基函数建立加减速规划的模型,并在其运动模型中增加匀加加速度加减速阶段.针对数控加工中连续微线段拐角处加工效率低、插补轨迹连续性低的问题,提出了新的一步法拐角过渡方法.该方法是通过一步法拐角过渡算法在速度规划阶段直接完成轨迹光顺.最后根据轮廓误差和机床各轴动态性能的限制对过渡时间、速度、加速度及加加速度进行约束.实验证明,提出的方法能够进一步提高加工中的加减速柔性,能够利用最大加加速度持续加减速,且在保证加工效率的基础上提高伺服控制的跟随精度,使得误差检测的精度能够满足要求.
Acceleration and deceleration control is a key technology in numerical control systems,which affects the efficiency and stability of the processing parts.Concurrently,because the traditional numerical control system must generate numerous continuous micro line segments when machining complex curves and surfaces,it increases the burden on the numerical control system,and the position is G0 continuous,resulting in frequent acceleration and deceleration and machine vibration at the corner,thus reducing the efficiency and quality of the processing parts.The two-step corner transition involves smoothing the track first and planning the speed later,which is not only complicated,but also reduces the processing efficiency.Therefore,given the problem that the maximum jerk in the traditional trigonometric function only has the peak value reducing machining efficiency,this study improves the acceleration and deceleration control algorithm of the traditional trigonometric function with optimal continuity of accelera-tion and deceleration,establishes the acceleration and deceleration planning model with sin^(2) x as the basic function of jerk,and incorporates the acceleration and deceleration phases of uniform jerk into its motion model.A new one-step corner transition method is proposed to solve the problems of low efficiency and continuity of interpolation trajectory in numerical control machining.In this method,the one-step corner transition algorithm is used to directly achieve trajectory smoothing in the velocity planning stage.Finally,the transition time,feedrate,acceleration and jerk are constrained according to the contour error and the dynamic performance of each axis.Experimental results show that the proposed method can further improve the acceleration and deceleration flexibility in machining.Besides,it can use the maximum jerk for acceleration and deceleration continuously,and improve the accuracy of servo control to ensure machining efficiency,so that the accuracy of error detection meets the requirements.
作者
王太勇
贾松辉
陈木正
Wang Taiyong;Jia Songhui;Chen Muzheng(School of Mechanical Engineering,Tianjin University,Tianjin 300350,China)
出处
《天津大学学报（自然科学与工程技术版）》
EI
CAS
CSCD
北大核心
2024年第10期1001-1009,共9页
Journal of Tianjin University：Science and Technology
基金
国家自然科学基金资助项目(51975407)
国家重点研发计划资助项目(2022YFB3303601).
关键词
拐角过渡
三角函数加减速
柔性加减速
数控系统
corner transition
trigonometric acceleration and deceleration
flexible acceleration and deceleration
numerical control system
