Synchronisation of Feed Axes with Differing Bandwidths Using Set Point Delay

This paper presents an effective method for the synchronisation of multiple feed axes with differing controller bandwidths by delaying the set point trajectories of those axes with higher bandwidths. First, a simplified model of a cascade-controlled feed axis is defined, which allows the problem to be treated analytically. The problem of synchronisation of the feed axes is then analysed mathematically, leading to the hypothesis of synchronisation through a delay of the set points of the more dynamic axes. Subsequently, the dynamic error behaviour and boundaries of a feed axis are calculated. The optimal damping factor for a feed axis is shown to be 1/ √ 2 and the dynamic error can be formulated in terms of the bandwidth and acceleration or jerk limit. The proposed method is proven through a simulation and verified based on experimental results. In addition, the stated error bounds are verified, and the limits of the applicability are determined.