JACIII Vol.21 No.2 pp. 228-234
doi: 10.20965/jaciii.2017.p0228


Extracting Initial Iterative Control Signal Based on Trajectory Primitives Matching and Combining

Jianming Xu, Lingxin Kong, and Yaodong Wang

College of Information Engineering, Zhejiang University of Technology
Hangzhou, Zhejiang, China

July 5, 2016
October 31, 2016
Online released:
March 15, 2017
March 20, 2017
iterative learning control, initial iterative control signal, trajectory primitive, optimal matching and combining algorithm, combined primitive sequence

The initial iterative control signal is often adopted a zero or a certain value in the conventional iterative learning control (ILC) system, and an ILC process needs to renew again as long as the desired trajectory is changed. In this paper, the NURBS (Non-Uniform Rational B-Splines) model is used for describing all trajectory primitives and the desired trajectory. It is studied that the problem of the initial iterative control signal is extracted in ILC, which presents a method of extracting the initial iterative control signal based on the trajectory primitive optimal matching and combining algorithm. Firstly, the definition of the similarity index between the two different spacial trajectories is introduced. Secondly, an optimal matching and combining algorithm is designed under a certain similarity index, which is used to find two or more combined primitive sequences with space patterns similar to the desired trajectory. Thirdly, the initial iterative control signals of the desired trajectory are extracted by using the control information of the combined primitive sequences. Finally, the simulation is carried out to demonstrate the effectiveness of the present method.

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Last updated on Mar. 24, 2017