Optimal LQ feedforward tracking with preview: Practical design for rigid body motion control

• Main Authors: Matthew O T Cole, Theeraphong Wongratanaphisan
• Format: Journal
• Published: 2018
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84897713204&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/45054
• Institution: Chiang Mai University

For reference-tracking motion control, preview-based linear quadratic (LQ) design methods provide an effective means to balance tracking performance with available actuation capacity. This paper considers a control structure for which the optimal feedforward controller is independent of the feedback controller. In this way, explicit implementation formulas for feedforward controllers are derived that can be applied to a range of rigid-body motion systems. Key aspects of the optimal LQ solutions are identified, particularly how the choice of design weightings affect steady-state error for polynomial tracking. A redesign procedure for finite preview-time is proposed that preserves exact polynomial tracking properties and control bandwidth of the optimal solutions. Comparative experimental results are presented for a motor-driven linear motion stage. © 2013 Elsevier Ltd.