Accurate physical modeling and synchronization control of dual-linear-motor-driven gantry with dynamic load

Abstract

To achieve high-accuracy tracking of dual-linear-motor-driven (DLMD) gantry, high-level synchronization between redundant actuators is a nonnegligible factor and also a difficult issue to be solved prior. Especially, when both XY axes are simultaneously operating to accomplish complex tasks efficiently, additional coupling effects will be generated by the dynamic load presented on the crossbeam, which makes the synchronization issue more complicated compared to the case with static load. However, due to the absence of an accurate model to fully reveal the complete coupling characteristics, existing approaches to this issue still have inherent limitations. Therefore, this paper focuses on the systematic physical modeling and synchronization control of DLMD gantry with a dynamic load presented on the crossbeam. A complete coupling mathematical model is established firstly, by fully considering two linear motions (X-axis and Y-axis) and also including the additional rotational motion of the crossbeam. Built upon the effective model information, corresponding solutions by compensating the dynamic load effects and actively controlling the rotational dynamic to regulate the internal forces have been proposed, leading to a novel adaptive robust synchronization control method. Comparative experiments are carried out, and the results show the effectiveness and superiority of the proposed method in dealing with synchronization issue subjected to dynamic load effects.

2-DOF MIMO decoupling control of the gantry high performance motion system

“…It can be seen from formula (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) that if the tracking error e is reduced to zero, F = G , the design principle of the feedforward controller F is to approximate the inverse of the controlled object model as much as possible.…”

“…This coupling is nonlinear because it is dependent on Y-position of the stage. Further, the motor force must be transformed into driving force/torque to each degree-of-freedom motion [5,6,7]. Therefore, the special structural design of the gantry high performance motion system increases the complexity of modeling and the design difficulty of motion controller.…”

A tracking control design for linear motor using robust sliding mode learning control

“…From the aforementioned beneficial features, LM has been widely utilized in various applications such as dual stage actuation [2], real nanopositioning system [3], industrial gantry [4], high speed applications [5] to name a few. However, many uncertain factors may significantly degrade the control performance of LM tracking task.…”