061 Feedforward tracking controller design for high-speed motion control

Several methodologies are proposed for identifying the dynamics of a machine tool feed drive system in the low frequency region. An accurate identification is necessary for the design of a feedforward tracking controller, which achieves unity gain and zero phase shift for the overall system in the relevant frequency band. In machine tools and other mechanical systems, the spectrum of the reference trajectory is composed of low frequency signals. Standard least squares fits are shown to heavily penalize high frequency misfit. Linear models described by the output-error (OE) and Autoregressive Moving Average with eXogenous Input (ARMAX) models display better closeness-of-fit properties at low frequency. Based on the identification, a feedforward compensator is designed using the Zero Phase Error Tracking Controller (ZPETC). The feedforward compensator is experimentally shown to achieve near-perfect tracking and contouring of high-speed trajectories on a machining center X-Y bed.

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Robust Digital Tracking Controller Design for High-speed Positioning Systems

1993 American Control Conference ◽

10.23919/acc.1993.4793339 ◽

1993 ◽

Cited By ~ 47

Author(s):

S. Endo ◽

M. Tomizuka ◽

Y. Hori

Keyword(s):

High Speed ◽

Controller Design ◽

Positioning Systems ◽

Tracking Controller ◽

Digital Tracking

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Flatness-Based Aggressive Formation Tracking Control of Quadrotors with Finite-Time Estimated Feedforwards

Applied Sciences ◽

10.3390/app11020792 ◽

2021 ◽

Vol 11 (2) ◽

pp. 792

Author(s):

Zhicheng Hou ◽

Gong Zhang ◽

Wenlin Yang ◽

Weijun Wang ◽

Changsoo Han

Keyword(s):

Motion Control ◽

Finite Time ◽

Attitude Control ◽

Tracking Control ◽

Controller Design ◽

High Order ◽

Experimental Results ◽

Formation Tracking ◽

Tracking Controller ◽

Formation Pattern

In this paper we address a decentralized neighbor-based formation tracking control of multiple quadrotors with leader–follower structure. Different from most of the existing work, the formation tracking controller is given in one loop without distinguishing the motion control and attitude control by means of the theory of flatness. In order to achieve an aggressive formation tracking, the high-order states of the neighbors motion are estimated by using a proposed extended finite-time observer for each quadrotor. Then the estimated motion states are used as feedforwards in the formation controller design. Simulation and experimental results show that the proposed formation controller improves the formation performance, i.e., the formation pattern of the quadrotors is better maintained than that using the formation controller without high-order feedforwards, when tracking an aggressive reference formation trajectory.

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