NURBS曲线插补过程中运动平滑处理

由于不能通过积分方法在短时间内精确计算NURBS曲线的长度,使得在数控加工过程中实时计算减速距离、判断最终减速段开始点变得非常困难。基于插补的实际情况,给出一种实时计算减速距离的方法,在此基础上,实现了基于梯形速度曲线的速度平滑处理以及基于S形速度曲线的加速度平滑处理。模拟结果表明,该方法在NURBS曲线实时插补过程中,在保证误差的基础上,满足了插补周期和加减速的要求,且实现了速度以及加速度的平滑过渡。

Motion Smoothing Implementation for NURBS Curve Interpolation

Due to the impossibility to compute the exact length of NURBS curve through integration in a short time,it is very difficult to get the deceleration distance and to forecast the point to begin the deceleration stage in real time.Based on the practical process,this paper presented a method to compute the deceleration distance in real time.With the result,trapezoidal velocity profile was adopted to smooth the velocity profile and S-curve velocity profile was adopted to smooth the acceleration profile.The simulation results show that the method presented here satisfies the needs of the interpolator cycle and the acceleration and deceleration besides ensuring the chordal errors.