数控加工中加减速控制及平滑算法的研究与实现

发布时间：2018-05-13 01:13

本文选题：加减速控制 + 平滑转接　；参考：《中国科学院大学(中国科学院沈阳计算技术研究所)》2017年硕士论文

【摘要】：随着我国经济的飞速发展,高精度仪器、航空航天等行业对数控系统高速高精柔性加工技术的要求也越来越高。常用加减速控制算法是对加工路径的物理参变量如加加速度、加速度、速度、位移进行规划,而加速度或者加加速度的不连续会导致数控系统的平稳性和柔性降低。为了防止上述情况,本文研究了现有数控系统加减速控制算法和连续微小线段间平滑转接算法,提出了基于圆弧的五段S型曲线柔性加减速控制算法。首先,研究了连续微小线段内的加减速控制算法;研究了几种常用加减速控制算法的原理及参数表达式,并对这些算法的优点和缺点进行比较和分析。其次,研究了连续微小线段间指令进给速度、加速度、加工误差、机床机械特性等约束因素对平滑转接的影响;研究了微小线段间的直接过渡算法、曲线拟合算法、圆弧过渡算法,并分析和比较了它们优缺点;讨论了如何根据加工需求选择合适的算法,以实现微小线段间的高速平滑衔接。再次,提出了基于圆弧的五段S型曲线柔性加减速控制算法,并给出了该算法的加加速度、加速度、速度、位移的数学模型;讨论了加工过程中可能会出现的各种情况,运用最优化控制原理对速度进行规划,实现高速高柔性加工。最后,对加减速控制算法、微小线段间的转接算法、基于圆弧的五段S型曲线柔性加减速算法进行仿真分析。仿真结果证明基于圆弧的五段S型加减速算法能够提高系统柔性,同时能使刀具以较高的转接速度通过相邻微小线段转接处。
[Abstract]:With the rapid development of economy in our country, the requirement of high speed and high precision flexible machining technology for NC system is more and more high in the industries of high precision instrument, aerospace and so on. The common acceleration and deceleration control algorithm is to plan the physical parameters of the machining path such as acceleration and displacement. The discontinuity of acceleration or acceleration will reduce the stability and flexibility of NC system. In order to prevent the above situation, this paper studies the existing acceleration and deceleration control algorithms and the smooth transfer algorithm between continuous small lines, and proposes a flexible acceleration and deceleration control algorithm based on circular arc for five-segment S-shaped curves. Firstly, the acceleration and deceleration control algorithms in continuous small line segments are studied, the principle and parameter expressions of several commonly used acceleration and deceleration control algorithms are studied, and the advantages and disadvantages of these algorithms are compared and analyzed. Secondly, the influence of the constraint factors such as feed speed, machining error and machine tool mechanical characteristics on smooth transition is studied, and the direct transition algorithm and curve fitting algorithm are studied. The arc transition algorithms are analyzed and compared, and how to select the appropriate algorithm according to the processing requirements is discussed in order to realize the high-speed smooth connection between small line segments. Thirdly, a flexible acceleration and deceleration control algorithm based on circular arc is proposed, and the mathematical model of acceleration and displacement of the algorithm is given. The optimum control principle is used to plan the speed and realize the high speed and high flexibility machining. Finally, the acceleration and deceleration control algorithm, the transfer algorithm between tiny lines, and the flexible acceleration and deceleration algorithm based on circular arc for five-segment S-shaped curves are simulated and analyzed. The simulation results show that the five-segment S-type acceleration and deceleration algorithm based on circular arc can improve the flexibility of the system and enable the tool to transfer through the adjacent micro-segment at a higher speed.
【学位授予单位】：中国科学院大学(中国科学院沈阳计算技术研究所)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG659;TP13

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