由于路径规划过程与速度规划过程之间缺乏信息交换,加工过程会出现加工速度与加工质量降低的现象,针对这一问题,提出了种高速、高精的路径动态前瞻规划算法。根据相邻加工路径之间的关系,规划出过渡圆弧半径的初始值;根据当前过渡圆弧与相邻的前一个过渡圆弧之间的关系,调整当前过渡圆弧的半径值;利用前瞻算法,结合具体的速度规划方式,进一步调整过渡圆弧的半径值,以确保加工过程中刀具既可以加速到路径所允许的最大速度,又可以在减速点前进行有效的减速。试验表明,通过将路径规划过程与速度规划过程相结合,算法在系统允许的误差范围内实现了有效的路径规划,并且最大程度地提高了加工速度,在保证加工精度的同时,提高了加工效率。
Since there is no interactive information exchange between path planning process and velocity planning process, the machining velocity and quality may be reduced. To solve this problem, a look-ahead path planning algorithm with high speed and high precision is given. The initial value of the radius for the transition circle is given based on the relationship of adjacent paths. The radius of current transition circle is adjusted according to the previous transition circle. The final value of the radius is decided based on the look-ahead algorithm and velocity planning algorithm and the resulting radius makes the maximum speed permitted by the machining path and the minimum speed needed by the deceleration points can be achieved. The experimental results show that the algorithm achieves the goals of high speed machining and high precision machining through the combination of path planning and velocity planning.
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