LAUSR

In this work, the design of a novel the flexure-linked dual-drive H-gantry is first introduced. Compared to conventional stacked X–Y tables, the advantages of this gantry are on decoupled X–Y actuation, better mechanical reliability, larger driving force, and shorter response time. However, after deriving its reduced-order dynamical model, it is found that the precision of the end-effector is significantly affected by the position dependent torque caused by the inter-parallel-axes driving forces on the fixed inertia frame and coupling forces from the pair of flexures. These form barriers that limit precision positioning and tracking performance over a large workspace. Thus, in the following part, a robust integral of signum of error (RISE) control with novel jerk adaptation is proposed on top of the standard proportional-integral-derivative (PID) and feedforward scheme. Compared with some prior RISE schemes with gain adaptation, the proposed scheme yields bounded robust gain in the presence of noisy velocity estimation. Real-time experiments on the actual testbed indicate that both improvement of motion precision and prevention of resonant mode excitation over a large workspace are successfully achieved in the proposed scheme.