Research on automatic parking system based on linear quadratic regulator

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yan Qian ◽  
Zhaoqiang Wang ◽  
Wei Liang ◽  
Chenhui Lu
Keyword(s):  
Feedback Control ◽  
Simulation Analysis ◽  
Feedforward Control ◽  
Linear Quadratic Regulator ◽  
Path Tracking ◽  
Linear Quadratic ◽  
Content Type ◽  
Tracking Controller ◽  
Automatic Parking ◽  
Continuous Curvature

PurposeThe purpose of this study is to solve the problem of path planning and path tracking in the automatic parking assistant system.Design/methodology/approachThis paper first uses the method of reverse driving to confirm few control points based on the constraints of the construction of the vehicle and the environment information, then a reference path with free-collision and continuous curvature is designed based on the Bézier curve. According to the principle of the discrete linear quadratic regulator (LQR), a tracking controller that combines feedforward control and feedback control is designed.FindingsFinally, simulation analysis are carried out in Simulink and CARSIM. The results show that the proposed method can obtain a better path tracking effect when the parking space size is appropriate.Originality/valueAccording to the principle of the discrete LQR, a tracking controller that combines feedforward control and feedback control is designed.

Path tracking control of 4-wheel-steering autonomous ground vehicles based on linear parameter-varying system with experimental verification

2020 ◽  
pp. 095965182093457
Author(s):  
Peng Hang ◽  
Xinbo Chen
Keyword(s):  
Tracking Control ◽  
Linear Quadratic Regulator ◽  
Path Tracking ◽  
Linear Parameter ◽  
Linear Quadratic ◽  
Linear Parameter Varying ◽  
Ground Vehicle ◽  
Tracking Controller ◽  
Road Friction ◽  
Linear Parameter Varying System

In this study, a novel 4-wheel-steering electric vehicle is proposed as an autonomous ground vehicle. It aims to study the path tracking control algorithm of the 4-wheel-steering autonomous ground vehicle for intelligent driving.. Path tracking model is built for path tracking controller design based on a single track model. Besides, the linear parameter-varying system model is constructed to make the path tracking controller adaptive to different longitudinal velocities and road friction coefficients. Furthermore, a linear quadratic regulator controller for path tracking is designed and stability analysis is carried out. To eliminate the error caused by disturbance, feedforward control is combined with a linear quadratic regulator controller. To verify the path tracking performance of the designed controller, numerical simulations are carried out based on a high-fidelity and full-vehicle model constructed in CarSim. Moreover, real road experiments are performed. Both the simulation results and experiment results show that the designed controller has good path tracking performance. In addition, the path tracking controller shows good robustness to deal with different longitudinal velocities and road friction coefficients.

Autopilot design for an aircraft by using Luenberger observer design

2018 ◽  
Vol 90 (5) ◽  
pp. 858-868 ◽  
Author(s):  
Muhammad Taimoor ◽  
Li Aijun ◽  
Rooh ul Amin ◽  
Hongshi Lu
Keyword(s):  
Design Methodology ◽  
Research Work ◽  
Linear Quadratic Regulator ◽  
Observer Design ◽  
Linear Quadratic ◽  
Content Type ◽  
Luenberger Observer ◽  
Level Flight ◽  
Aerial Vehicle ◽  
The Cost

Purpose The purpose of this paper is to design linear quadratic regulator (LQR) based Luenberger observer for the estimation of unknown states of aircraft. Design/methodology/approach In this paper, the LQR-based Luenberger observer is deliberated for autonomous level flight of unmanned aerial vehicle (UAV) which has been attained productively. Various modes like phugoid and roll modes are exploited for controlling the rates of UAV. The Luenberger observer is exploited for estimation of the mysterious states of the system. The rates of roll, yaw and pitch are used as an input to the observer, while the remaining states such as velocities and angles have been anticipated. The main advantage of using Luenberger observer was to reduce the cost of the system which has been achieved lucratively. The Luenberger observer proposes sturdiness at the rate of completion to conquest over the turmoil and insecurities to overcome the privileged recital. The FlightGear simulator is exploited for the endorsement of the recital of the Luenberger observer-based autopilot. The level flight has been subjugated lucratively and has been legitimated by exploiting the FlightGear simulator. The authenticated and the validated results are offered in this paper. Microsoft Visual Studio has been engaged as a medium between the MATLAB and FlightGear Simulator. Findings The suggested observer based on LQR ensures the lucrative approximation of the unknown states of the system as well as the successful level flight of the system. The Luenberger observer is used for approximation of states while LQR is used as controller. Originality/value In this research work, not only the estimation of unknown states of both longitudinal and lateral model is made but also the level flight is achieved by using those estimated states and the autopilot is validated by using the FlightGear, while in most of the research work only the estimation is made of only longitudinal or lateral model.

An automatic system for a helicopter autopilot performance evaluation

2019 ◽  
Vol 91 (6) ◽  
pp. 880-885 ◽  
Author(s):  
Antoni Kopyt ◽  
Sebastian Topczewski ◽  
Marcin Zugaj ◽  
Przemyslaw Bibik
Keyword(s):  
Performance Evaluation ◽  
Flight Control ◽  
Automatic System ◽  
Control Algorithm ◽  
Linear Quadratic Regulator ◽  
Algorithm Analysis ◽  
Evaluation Methodology ◽  
Reference Trajectory ◽  
Linear Quadratic ◽  
Content Type

Purpose The purpose of this paper is to elaborate and develop an automatic system for automatic flight control system (AFCS) performance evaluation. Consequently, the developed AFCS algorithm is implemented and tested in a virtual environment on one of the mission task elements (MTEs) described in Aeronautical Design Standard 33 (ADS-33) performance specification. Design/methodology/approach Control algorithm is based on the Linear Quadratic Regulator (LQR) which is adopted to work as a controller in this case. Developed controller allows for automatic flight of the helicopter via desired three-dimensional trajectory by calculating iteratively deviations between desired and actual helicopter position and multiplying it by gains obtained from the LQR methodology. For the AFCS algorithm validation, the objective data analysis is done based on specified task accomplishment requirements, reference trajectory and actual flight parameters. Findings In the paper, a description of an automatic flight control algorithm for small helicopter and its evaluation methodology is presented. Necessary information about helicopter dynamic model is included. The test and algorithm analysis are performed on a slalom maneuver, on which the handling qualities are calculated. Practical implications Developed automatic flight control algorithm can be adapted and used in autopilot for a small helicopter. Methodology of evaluation of an AFCS performance can be used in different applications and cases. Originality/value In the paper, an automatic flight control algorithm for small helicopter and solution for the validation of developed AFCS algorithms are presented.

Analytical and Experimental Evaluation of Various Active Suspension Alternatives for Superior Ride Comfort and Utilization of Autonomous Vehicles

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Ivan Cvok ◽  
Mario Hrgetić ◽  
Matija Hoić ◽  
Joško Deur ◽  
Davor Hrovat ◽  
...  
Keyword(s):  
Autonomous Vehicles ◽  
High Performance ◽  
Ride Comfort ◽  
Simulation Analysis ◽  
Linear Quadratic Regulator ◽  
Active Suspension ◽  
Vertical Acceleration ◽  
Linear Quadratic ◽  
Seat Suspension ◽  
Road Disturbance

Abstract Autonomous vehicles (AVs) give the driver opportunity to engage in productive or pleasure-related activities, which will increase AV’s utility and value. It is anticipated that many AVs will be equipped with active suspension extended with road disturbance preview capability to provide the necessary superior ride comfort resulting in almost steady work or play platform. This article deals with assessing the benefits of introducing various active suspensions and related linear quadratic regulator (LQR) controls in terms of improving the work/leisure ability. The study relies on high-performance shaker rig-based tests of a group of 44 drivers involved in reading/writing, drawing, and subjective ride comfort rating tasks. The test results indicate that there is a threshold of root-mean-square vertical acceleration, below which the task execution performance is similar to that corresponding to standstill conditions. For the given, relatively harsh road disturbance profile, only the fully active suspension with road preview control can suppress the vertical acceleration below the above critical superior comfort threshold. However, when adding an active seat suspension, the range of chassis suspension types for superior ride comfort is substantially extended and can include semi-active suspension and even passive suspension in some extreme cases that can, however, lead to excessive relative motion between the seat and the vehicle floor. The design requirements gained through simulation analysis, and extended with cost and packaging requirements related to passenger car applications, have guided design of two active seat suspension concepts applicable to the shaker rig and production vehicles.

scholarly journals Driverless Bus Path Tracking Based on Fuzzy Pure Pursuit Control with a Front Axle Reference

2019 ◽  
Vol 10 (1) ◽  
pp. 230 ◽  
Author(s):  
Lingli Yu ◽  
Xiaoxin Yan ◽  
Zongxu Kuang ◽  
Baifan Chen ◽  
Yuqian Zhao
Keyword(s):  
Feedforward Control ◽  
Forward Direction ◽  
Front Axle ◽  
Path Tracking ◽  
Tuning Method ◽  
Tracking Controller ◽  
Pursuit Control ◽  
Pure Pursuit ◽  
The Stability ◽  
Fuzzy Parameter

Currently, since the model of a driverless bus is not clear, it is difficult for most traditional path tracking methods to achieve a trade-off between accuracy and stability, especially in the case of driverless buses. In terms of solving this problem, a path-tracking controller based on a Fuzzy Pure Pursuit Control with a Front Axle Reference (FPPC-FAR) is proposed in this paper. Firstly, the reference point of Pure Pursuit is moved from the rear axle to the front axle. It relieves the influence caused by the ignorance of the bus’s lateral dynamic characteristics and improves the stability of Pure Pursuit. Secondly, a fuzzy parameter self-tuning method is applied to improve the accuracy and robustness of the path-tracking controller. Thirdly, a feedback-feedforward control algorithm is devised for velocity control, which enhances the velocity tracking efficiency. The proportional-integral (PI) controller is indicated for feedback control, and the gravity acceleration component in the car’s forward direction is used in feedforward control. Finally, a series of experiments is conducted to illustrate the excellent performances of proposed methods.

LQG Control Design for Vehicle Active Anti-Roll Bar System

2014 ◽  
Vol 663 ◽  
pp. 146-151 ◽  
Author(s):  
Noraishikin Zulkarnain ◽  
Hairi Zamzuri ◽  
Saiful Amri Mazlan
Keyword(s):  
Ride Comfort ◽  
Simulation Analysis ◽  
Control Strategies ◽  
Dynamic Modelling ◽  
Linear Quadratic Regulator ◽  
Vehicle Body ◽  
Linear Quadratic ◽  
Linear Quadratic Gaussian ◽  
Roll Rate ◽  
External Forces

The objective of this paper is to design a linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) controllers for an active anti-roll bar system. The use of an active anti-roll bar will be analysed from two different perspectives in vehicle ride comfort and handling performances. This paper proposed the basic vehicle dynamic modelling with four degree of freedom (DOF) on half car model and are described that show, why and how it is possible to control the handling and ride comfort of the car, with the external forces also control strategies on the front anti-roll bar. By simulation analysis, the design model is validity and the performance under control of linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) controller are achieved. Both two controllers are modeled in MATLAB/SIMULINK environment. It has to be determined which control strategy delivers better performance with respect to roll angle and the roll rate of half vehicle body. The result shows, however, that LQG produced better response compared to a LQR strategy.

Dynamics and control of a flexible rotating clamped-free beam by SDRE strategy

2019 ◽  
Vol 91 (7) ◽  
pp. 1018-1026
Author(s):  
Vinicius Piro Barragam ◽  
Andre Fenili ◽  
Ijar Milagre da Fonseca
Keyword(s):  
Riccati Equation ◽  
Numerical Solutions ◽  
Linear Quadratic Regulator ◽  
Flexible Beam ◽  
Problem Solution ◽  
Integration Step ◽  
Linear Quadratic ◽  
Planar Case ◽  
Content Type ◽  
Practical Implications

Purpose The purpose of this paper is the dynamic analysis of the coupled rotation and vibration motion of a system containing a central rigid body to which is attached a flexible beam. Design/methodology/approach The methodology includes the Lagrange’s formulation by using the extended Hamilton’s Principle in conjunction with the assumed modes method to describe the system of equations by ordinary differential equations. The first unconstrained mode of vibration was considered as the solution for the transversal displacement. Such mode emerges as the eigenvalue problem solution associated to the dynamics of the system. The control strategy adopted is a nonlinear analogy of the linear quadratic regulator problem as the Riccati equation is solved at every integration step during the numerical solutions. This strategy is known as state-dependent Riccati equation. Findings By means of computational simulations, it was found the relation between controlled motion and inertia ratio. Research limitations/implications This work is limited to planar case and fixed hub. Practical implications Practical implications of this work realize the design of lighter yet dexterous structures. Originality/value The contribution of this paper is the position and vibration control of a flexible beam accounting for nonlinearity effects and the fact that the structure to where it is clamped has a comparable inertia.

Vehicle direct yaw moment control system based on the improved linear quadratic regulator

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xianyi Xie ◽  
Lisheng Jin ◽  
Guo Baicang ◽  
Jian Shi
Keyword(s):  
Linear Quadratic Regulator ◽  
Objective Evaluation ◽  
Linear Quadratic ◽  
Vehicle Handling ◽  
Content Type ◽  
The Road ◽  
Direct Yaw Moment Control ◽  
Yaw Moment Control ◽  
Moment Control ◽  
Yaw Moment

Purpose This study aims to propose an improved linear quadratic regulator (LQR) based on the adjusting weight coefficient, which is used to improve the performance of the vehicle direct yaw moment control (DYC) system. Design/methodology/approach After analyzing the responses of the side-slip angle and the yaw rate of the vehicle when driving under different road adhesion coefficients, the genetic algorithm and fuzzy logic theory were applied to design the parameter regulator for an improved LQR. This parameter regulator works according to the changes in the road adhesion coefficient between the tires and the road. Hardware-in-the-loop (HiL) tests with double-lane changes under low and high road surface adhesion coefficients were carried out. Findings The HiL test results demonstrate the proposed controllers’ effectiveness and reasonableness and satisfy the real-time requirement. The effectiveness of the proposed controller was also proven using the vehicle-handling stability objective evaluation method. Originality/value The objective evaluation results reveal better performance using the improved LQR DYC controller than a front wheel steering vehicle, especially in reducing driver fatigue, improving vehicle-handling stability and enhancing driving safety.

Sign in / Sign up

Export Citation Format

Share Document