插补前S加减速在CNC前瞻中的应用论述.pdf

2007年 5月 第33卷第5期 北京航空航天大学学报 Journal of Beijing uniVersity of Aeronautics and Astronautics Mav 2007 V01．33 No．5 插补前S加减速在CNC前瞻中的应用 曹宇男 王田苗 陈友东 魏洪兴 (北京航空航天大学机械工程及自动化学院，北京100083) 摘 要：计算机数字控制系统(cNc)中的速度前瞻处理可以在不影响插补轨迹精度 的前提下极大地提高插补效率．针对前瞻算法中速度处理这一核心问题，分直线转接和圆弧转 接2种情况分别建立了插补几何元素转接矢量夹角模型，并给出了一种基于插补前s型加减 速的CNC速度前瞻算法．该算法根据设定的最大前瞻段数以及实际插补轨迹的几何特性，能 够自适应确定轨迹的转接速度近似最优解，从而实现路径段之间进给速度的高速衔接．s型加 减速由于在加速阶段和减速阶段均引入了加速度衰减，使得整个插补过程具有了高度的柔性． 因此结合前瞻算法和s型加减速算法在高速加工时速度处理的优势，提出并实现了一种基于 插补前s型加减速的cNc前瞻算法．该算法已经在工程实际中得到了验证． 关 键 词：加速度控制；插补；数控系统；角度测量 中图分类号：TP 273 文献标识码：A 文章编号：100l一5965(2007)05加594Ⅲ6 App¨cation of pre-interpoIation S-shape acceIeration／decebration in CNC IOOk-ahead interpOIatiOn algOrithm Cao Yunan Wang Tianmiao Chen Youdong Wei Hongxing (School of Mechanical E“gineeri“g and Automation，Be玎ing University of Aeronautics and Astronautic8，Be玎i“g 100083，China) AbStraCt：Aiming at improving the interp01ation efficiency without 10wering the path accuracy，the veloci- ty look—ahead control in CNC(computerized numerical contr01) was introduced． Firstly，the inteIpolation ge— ometIy elements linking vector an91e model， which was separated into line—connect condition and circle—con— nect condition，was proposed． The CNC velocity look—ahead control algorithm was presented． This noVel algo— rithm can find the approximate optimal velocity adaptatiVely based on the maximum number of 100k-ahead seg— ments and the geometric properties of the interpolation path， then the high connected Velocities between seg— ments can be achieved． Because introducing the acceleration attenuation in acceleration zone and deceleration zone，the S—shape acc／dec(acceleration／decelemtion) can improve the nexibility of interpolation． By combi- ning the advantages of the 100k—ahead contr01 algorithm and the S-shape acc／dec in high Velocity condition，a novel S-shape acc／dec CNC look—ahead interpolation algorithm was introduced and realized． This algorithm feasibility has already been proVed in real CNC system． Key wOrds：accelemt