International Journal of Control, Vol.77, No.13, 1189-1199, 2004
Multi-channel learning using anticipatory ILCs
In general, a linear system with a single iterative learning controller (ILC) has a limited learnable frequency bandwidth. This limitation affects learning transient and final tracking accuracy. In this paper, a multi-channel method is proposed to extend the learning frequency bandwidth beyong that achievable by a single ILC. Each channel requires a single learning controller designed to fit the system dyanmics within this designated frequency band. To prepare tracking errors for each channel, DFT/IDFT and zero-phase filters are used. Learning using anticipatory learning control under the multi-channel structure is analysed in detail. The design procedure and effectiveness of the multi-channel method are demonstrated via simulations and experiments. Comparison of the multi-channel learning control with the conventional single-channel learning control highlights the merits of the multi-channel design method.