Tracking of a Target Payload via a Combination of Input Shaping, Zero Phase Error Tracking Control, and Fuzzy Logic

2016 ◽  
Author(s):  
Robert Schmidt ◽  
Matthew Begneaud ◽  
Joshua Vaughan
Keyword(s):  
Fuzzy Logic ◽  
Tracking Control ◽  
Phase Error ◽  
Input Shaping ◽  
Membership Functions ◽  
Tracking Accuracy ◽  
Autonomous Surface Vehicle ◽  
Tracking Controller ◽  
Initial Move ◽  
Zero Phase

During crane operation, the task of retrieval and deployment of payloads can be partitioned into two components: the initial move towards the target or deployment location and the retrieval or deployment of the payload. If the payload is not stationary, as is the case in the retrieval of a sea-going vessel, a third component, tracking, must be included. The target payload in this research is an Autonomous Surface Vehicle (ASV) primarily used for surveying. This paper studies the transition between the initial move towards the payload and the initialization of tracking. Input Shaping is used to limit residual vibration caused by the initial move to the ASV. A set of Fuzzy Logic membership functions are then used to transition from the initial move to the tracking portion of the retrieval process. These membership functions map position and velocity error to a gain that is applied to the tracking controller. As the gain increases, the contribution of the tracking controller input is increased. Zero Phase Error Tracking Control is utilized for accurate tracking of the target payload. Through a combination of these control methods, the tracking accuracy is improved.

Tracking Control of Non-Minimum Phase Systems Using Filtered Basis Functions: A NURBS-Based Approach

2015 ◽  
Author(s):  
Molong Duan ◽  
Keval S. Ramani ◽  
Chinedum E. Okwudire
Keyword(s):  
Tracking Control ◽  
Phase Error ◽  
Approximate Model ◽  
Basis Functions ◽  
Minimum Phase ◽  
Tracking Errors ◽  
Model Inversion ◽  
B Spline ◽  
Phase Systems ◽  
Zero Phase

This paper proposes an approach for minimizing tracking errors in systems with non-minimum phase (NMP) zeros by using filtered basis functions. The output of the tracking controller is represented as a linear combination of basis functions having unknown coefficients. The basis functions are forward filtered using the dynamics of the NMP system and their coefficients selected to minimize the errors in tracking a given trajectory. The control designer is free to choose any suitable set of basis functions but, in this paper, a set of basis functions derived from the widely-used non uniform rational B-spline (NURBS) curve is employed. Analyses and illustrative examples are presented to demonstrate the effectiveness of the proposed approach in comparison to popular approximate model inversion methods like zero phase error tracking control.

Precision motion control of permanent magnet linear synchronous motor servo system based on an integrated controller with inertia variation compensation

2012 ◽  
Vol 227 (7) ◽  
pp. 1481-1494 ◽  
Author(s):  
Zhijun Li ◽  
Chengying Liu ◽  
Fanwei Meng ◽  
Kai Zhou
Keyword(s):  
Permanent Magnet ◽  
Motion Control ◽  
Disturbance Observer ◽  
Phase Error ◽  
Servo System ◽  
Tracking Performance ◽  
Tracking Controller ◽  
Integrated Controller ◽  
Feed Forward Controller ◽  
Zero Phase

To achieve high robustness and precise motion control of permanent magnet linear synchronous motor servo system, an integrated controller is presented, including a velocity feed forward controller, a zero phase error tracking controller, a disturbance observer and inertia variation compensator. The velocity feed forward controller and the zero phase error tracking controller are included to improve tracking performance and the disturbance observer is involved to enhance disturbance rejection. However, both the zero phase error tracking controller and the disturbance observer are sensitive to inertia variation which often occurs in servo systems. So, an inertia compensator, which consists of a perfect tracking controller for the current loop and a compensation gain, is proposed to retain tracking performance. Detailed experiments are conducted on a PMLSM servo system to confirm the effectiveness of the integrated controller.

Concurrent Design of Continuous Zero Phase Error Tracking Controller and Sinusoidal Trajectory for Improved Tracking Control

1998 ◽  
Vol 123 (1) ◽  
pp. 127-129 ◽  
Author(s):  
Hyung-Soon Park ◽  
Pyung Hun Chang ◽  
Doo Yong Lee
Keyword(s):  
Continuous Time ◽  
Phase Error ◽  
Phase System ◽  
Pass Filter ◽  
Nonminimum Phase ◽  
Tracking Controller ◽  
Feedforward Controller ◽  
Gain Errors ◽  
High Pass ◽  
Zero Phase

A trajectory control strategy for a nonminimum phase system is proposed. A continuous-time version of the Zero Phase Error Tracking Controller (ZPETC), which is a well-known discrete-time feedforward controller, is considered. In the continuous-time case, the overall transfer function consisting of the ZPETC and the closed-loop plant exhibits high-pass filter characteristics. This introduces serious gain errors between the desired and actual output if the desired output is made directly as the ZPETC’s input. This paper proposes the use of a specially designed sinusoidal trajectory to compensate for the gain errors. The sinusoidal trajectory imparts a synergic effect to tracking performance when combined with the continuous ZPETC. Continuous ZPETC with sinusoidal trajectory is evaluated successfully by applying to a nonminimum phase plant, single link flexible arm.

Simplified Realization of Zero Phase Error Tracking

2020 ◽  
Author(s):  
Masayoshi Tomizuka ◽  
Liting Sun
Keyword(s):  
Transfer Function ◽  
Tracking Control ◽  
Control Method ◽  
Feedforward Control ◽  
Phase Error ◽  
Time Varying ◽  
Time Transfer ◽  
Simple Implementation ◽  
Tracking Time ◽  
Zero Phase

Abstract Zero phase error tracking (ZPET) control has gained popularity as a simple yet effective feedforward control method for tracking time varying desired trajectories by the plant output. In this paper, we will show that the zero-order hold equivalent of continuous time transfer function, i.e. pulse transfer function, naturally has a property to realize zero phase effort tracking. This property is exploited to realize a simple implementation of zero phase error tracking control. The effectiveness of the proposed approach is demonstrated by simulations.

Sine phase compensation combining an amplitude phase controller and a discrete feed-forward compensator for electro-hydraulic shaking tables

2017 ◽  
Vol 40 (11) ◽  
pp. 3377-3389 ◽  
Author(s):  
Ge Li ◽  
Gang Shen ◽  
Zhen-Cai Zhu ◽  
Xiang Li ◽  
Wan-Shun Zang
Keyword(s):  
Control Strategy ◽  
Phase Error ◽  
Phase Delay ◽  
Shaking Table ◽  
Response Signal ◽  
Feed Forward ◽  
Amplitude Attenuation ◽  
Tracking Controller ◽  
Phase Deviation ◽  
Zero Phase

This article presents a novel control strategy on an electro-hydraulic shaking table under the acceleration control combining an amplitude phase controller and a zero phase error tracking controller with a discrete feed-forward compensator. Because of the electro-hydraulic system’s nonlinearity, phase delay and amplitude attenuation exist in the acceleration response signal inevitably when the electro-hydraulic shaking table system is excited by a sine vibration signal. Moreover, the phase delay of the electro-hydraulic shaking table is composed of phase deviation and actuator delay. For improving the acceleration tracking accuracy, an amplitude phase controller is employed to compensate the phase deviation and amplitude attenuation by introducing weights to adjust the reference signal. Meanwhile, the discrete feed-forward compensator is applied to compensate the actuator delay. As an offline compensator, the zero phase error tracking controller is employed to compensate the phase delay of the response signal and improve the convergence speed of the proposed controller. Overall, the proposed control strategy combines the merits of these three controllers with better tracking performance demonstrated by simulation and experimental results.

scholarly journals Optimal tracking control of a trajectory planned via fuzzy reactive approach for an autonomous mobile robot

2018 ◽  
Vol 15 (1) ◽  
pp. 172988141876062 ◽  
Author(s):  
Khaled Akka ◽  
Farid Khaber
Keyword(s):  
Fuzzy Logic ◽  
Mobile Robot ◽  
Objective Function ◽  
Tracking Control ◽  
Autonomous Mobile Robot ◽  
Linear Quadratic ◽  
Optimal Tracking ◽  
Tracking Controller ◽  
Scenarios Simulation ◽  
Simulation Results

This article deals with the design of an optimal tracking controller for a wheeled mobile robot. The tracking control can be performed to track either a given or a planned trajectory. In our study, an improved linear quadratic tracker is adopted to track a path planned using an improved reactive approach that combines the dynamic window with the fuzzy logic to make the robot movement toward the target faster, smoother, and safer whatever the complexity of the environment. The fuzzy logic is used to dynamically adjust the weights of the terms included in the dynamic window objective function according to different environmental scenarios. Simulation results of the path planning and the tracking control prove that the proposed approaches are significantly superior to the conventional ones.

Feedforward Tracking Controller Design Based on the Identification of Low Frequency Dynamics

1993 ◽  
Vol 115 (3) ◽  
pp. 348-356 ◽  
Author(s):  
E. D. Tung ◽  
M. Tomizuka
Keyword(s):  
High Speed ◽  
Linear Models ◽  
Controller Design ◽  
Phase Error ◽  
Low Frequency ◽  
Reference Trajectory ◽  
Accurate Identification ◽  
Tracking Controller ◽  
Feed Drive System ◽  
Zero Phase

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.

Sign in / Sign up

Export Citation Format

Share Document