毕业论文-GT-100系统速度规划和误差补偿算法研究与实现,共157页,41073字
中文摘要
GT-100 机床数控系统是清华-光洋数控技术联合实验室的产品,性能和功能
上的开发目标是比肩 FANUC-0i 系列产品。
本文首先总体介绍了数控技术发展现状,然后着重介绍了加减速控制、螺
距误差补偿、间隙补偿和螺纹插补的研究现状。毕业设计期间作者研究的课题
隶属于 GT-100 数控系统运动控制部分,主要包括:速度规划、螺距误差补偿和
间隙补偿、螺纹插补。
加减速控制是 CNC 系统开发的关键技术之一。在数控加工中,为了保证机
床在启动和停止时不产生冲击、失步、超程和振动,必须对进入进给伺服电机
的进给脉冲频率和电压进行加减速控制。本文采用插补前直线加减速控制、S 曲
线加减速控制对单段运行轨迹、连续轨迹进行了速度规划研究。
螺距误差和反向间隙属于数控机床的几何误差,使数控机床的坐标轴在运
动过程中产生运动误差,最终表现形式是机床的位置误差。二者均是准静态误
差,随时间缓慢变化而且与机床本身的机械结构有关。本文采用直线插值法进
行螺距误差补偿,采用平均值法进行间隙补偿。
螺纹加工是数控加工中的一个难点,它以主轴与进给轴的同步控制实现螺
纹加工。螺纹加工可以用镗刀或车刀在车床和铣床上实现。本文对螺纹插补的
算法进行了初步探索和研究。
对于每一部分研究内容,作者都进行了 Matlab 仿真验证,部分进行了实验
验证。
关键词:数控技术,加减速控制,螺距误差补偿,间隙补偿,螺纹插补
ABSTRACT
GT-100 machine tool NC system is a product of Tsinghua-Guangyang NC
Technology Coorperating Labratary, which is supposed to be as advanced as
FANUC-0i in capability and function.
After introducing the present developing situation of NC technology synoptically,
this paper introduces the present researching situation of acceleration/deceleration
control, screw-pitch and opposite clearance error compensation, thread interpolation
as emphasis. During the graduation project, the topics of the author mainly include:
velocity layout, screw-pitch and opposite clearance error compensation, thread
interpolation, which belong to the movement control part of GT-100 NC system.
Acceleration/deceleration control is a key technology of CNC system. When
machining with NC machine tools, we must control the pulse frequency and voltage
supplied to the feeding servo motor with acceleration/deceleration method in order to
avoid impact, out-of-step, overtravel and vibration when machine tools are started
and paused.In this paper,pre-interpolation linear and s-shape
acceleration/deceleration control are used to generate velocity profiles for
single-curve and continuous-curves tracks.
Errors affected by screw-pitch and opposite clearance, two kinds of geometrical
error of NC machine tools, which cause dynamic error when axes of machines are
moving, perform as position error finally. These two are both semi-static error, which
change frequently with time and influenced by the mechanic structure of the machine
tools. In this paper, we adopt linear interpolation method for screw-pitch error
compensation and average-value method for opposite clearance error compensation.
Thread processing is a piece of difficult work in NC machining, which requires
the synchronization of the main spindle and the feeding spindle. It can be done on
lathes and milling machines with boring or turning tool. In this paper, a pilot study is
done about thread interpolation.
For every part of the graduation project, the author did simulation with Matlab,
and some parts were also checked by experiments.
Keywords: numerical control technology, acceleration/deceleration control,
screw-pitch error compensation, opposite clearance error compensation, thread
interpolation
目录
中文摘要..........Ⅰ
ABSTRACT..........Ⅲ
目录 ......Ⅴ
第一章
绪 论 ............1
数控技术发展现状 .......... 1
加减速控制研究现状 ........ 2
螺距误差、反向间隙误差补偿研究现状......... 3
螺纹插补研究现状 .......... 4
第二章
毕设论文的主要内容 ........ 5
加减速基础知识介绍 ........ 7
数控系统插补前速度规划 ...........7
加减速控制算法介绍........... 7
转接速度确定方法..... 9
连续微段转接加减速处理方法.......... 12
单段运行直线轨迹速度规划.......... 13
直线加减速速度规划.......... 13
S 曲线加减速速度规划 ........ 15
单段运行圆弧轨迹速度规划.......... 23
直线加减速速度规划.......... 23
S 曲线加减速速度规划 ........ 24
连续轨迹运行速度规划 ..... 27
直线加减速速度规划.......... 27
连续轨迹运行 S 曲线加减速速度规划.... 35
微小线段连续运行速度规划.......... 39
算法验证 ......... 40
Matlab 仿真 ......... 40
实验验证 ........... 52
第三章
本章小结 ......... 61
数控加工螺距补偿和间隙补偿 .......63
螺距误差和反向间隙产生机理........ 63
螺距误差产生机理............ 63
反向间隙产生机理............ 64
螺补、间补算法研究与实现.......... 64
螺距误差补偿算法............ 64
反向间隙补偿算法............ 66
第四章
算法验证 ......... 66
本章小结 ......... 68
数控加工螺纹插补 ........69
螺纹插补基础知识介绍 ..... 69
螺纹插补算法与实现 ....... 69
直线加减速方式加速段插补.... 70
匀速段插补 ......... 71
直线加减速方式退尾段插补.... 72
变螺距处理 ......... 74
算法验证 ......... 74
本章小结 ......... 76
第五章
总结 ..........79
插图索引 ..........I
表格索引 ..........V