Automatic Steering Control Research Articles

Automated Steering Control Systems Design for Passenger Vehicle in Consideration of Vehicle Parameters' Uncertainties

Advanced safety vehicle (ASV) assists drivers' manipulations to avoid traffic accidents. In this paper, a control system for ASV is designed to avoid obstacles using an automated steering system. The control system is based on a visual feedback and the system model is built in consideration of dynamics of the lane and vehicle using an LFT description. The controller is designed by μ-synthesis such that the control system is robust against uncertainties for vehicle parameters. The performance of the designed control system is examined by numerical experiments for obstacle avoidance.

Experimental Study on Application of DGPS-based Position Information to Automatic Driving Control

Experimental studies are conducted for investigating the possibility of automatic driving control systems based on absolute position information. Implementation of such control system requires a methodology of measuring the absolute position, and a control algorithm. In this paper, an accurate and real-time estimation of the absolute position by use of DGPS (Differential Global Positioning System) and sensors on a controlled vehicle is proposed. Automatic steering controller, automatic evasive controller, and a method of relative position measurement of neighboring vehicles are also proposed as application of position information to automatic driving control. Experiments are conducted using sedan-type vehicles. Experimental results validate the proposed estimation and control system, and provide the perspective of enhancing the automatic driving control system by use of the absolute position information.

Robust automatic steering control for look-down reference systems with front and rear sensors

This paper describes a robust control design for automatic steering of passenger cars. Previous studies showed that reliable automatic driving at highway speed may not be achieved under practical conditions with look-down reference systems which use only one sensor at the front bumper to measure the lateral displacement of the vehicle from the lane reference. An additional lateral displacement sensor is added here at the tail bumper to solve the automatic steering control problem. The control design is performed stepwise: an initial controller is determined using the parameter space approach in an invariance plane; and this controller is then refined to accommodate practical constraints and finally optimized using the multiobjective optimization program. The performance and robustness of the final controller was verified experimentally at California PATH in a series of test runs.

Course Tracking Control Algorithm Using Visual Information

SUMMARY Automatic steering control algorithm has been proposed, which uses the motion of objects in a visual image (Optical Flow) obtained from an ITV camera looking ahead in the situation without forward vehicles. This algorithm is improved to be applicable to the situation in which the forward tracking course is invisible owing to the interfarence of the forward vehicles. The adjustment of the control parameters against the change in vehicle speed is confirmed by the computer simulation experiments.

Analysis of Automatic Steering Control for Highway Vehicles with Look-down Lateral Reference Systems

SUMMARY In this paper, steering control for passenger cars on automated highways is analyzed, concentrating on look-down reference systems. Extension of earlier experimental results for low speed to highway speed is shown to be non-trivial. The limitations of pure output-feedback of lateral vehicle displacement from the road reference are examined under practical constraints and performance requirements like robustness, maximum lateral error and comfort. The in-depth system analysis directly leads to a new alternative design direction which allows to preserve look-ahead reference systems for highway speed automatic driving.

Carrier-Phase DGPS for Closed-Loop Control of Farm and Construction Vehicles

Operating heavy equipment can be a difficult and very tedious task. Control of an agricultural tractor requires the continuous attention of the driver, and farmers often work long hours during critical times of planting and harvesting. Loaders and other ground vehicles are frequently used in situations that are unpleasant or even hazardous for a human operator. This paper explores the use of carrier-phase DGPS as the sole position and attitude sensor in closed-loop control of farm and construction vehicles. A land vehicle optimal control system was designed and simulated using realistic plant, sensor, and disturbance models. To validate this simulation, a GPS-equipped electric golf cart was driven to high accuracy under automatic steering control. Golf cart experimental data were examined in post-processing to determine the feasibility of on-line system identification with GPS.

An automatic steering control algorithm using optical flow

An automatic steering control algorithm is presented, which uses motion of objects in a visual image (Optical Flow) obtained from an ITV camera looking ahead. Computer simulation experiments are performed in order to evaluate the algorithm.

A Measuring Technology Applied the Latest High Technology ；An Example of Automatic Steering Control on Shield Tunnel Construction

A Measuring Technology Applied the Latest High Technology ；An Example of Automatic Steering Control on Shield Tunnel Construction

9436341 Proposal of an automatic steering control algorithm appling optical flow: Ken-ichi Yoshimoto (Univ. of Tokyo), Masatoshi Sakatoh (Honda), Makoto Takeuchi (Nissan), Hideki Ogawa (Tokyo Marine), pp. 137–140, 10 figs., 2 refs

9436341 Proposal of an automatic steering control algorithm appling optical flow: Ken-ichi Yoshimoto (Univ. of Tokyo), Masatoshi Sakatoh (Honda), Makoto Takeuchi (Nissan), Hideki Ogawa (Tokyo Marine), pp. 137–140, 10 figs., 2 refs

Visual control of an autonomous vehicle (BART)-the vehicle-following problem

The authors consider the problem of vehicle-following including automatic steering and speed control of an autonomous vehicle following the motion of a lead vehicle. A visual control system for vehicle-following is presented. The system consists of the following modules: image processing, recursive filtering, and a driving command generator. First, the range and heading signal of the lead vehicle are obtained by visually identifying a unique tracking feature on the lead vehicle. Based upon this information, appropriate steering wheel and speed commands for driving are generated, which are then downloaded and executed on a microprocessor controller. The visual control system was tested on BART (Binocular Autonomous Research Team), a testbed vehicle developed at Texas A&M University for autonomous mobility. Successful full-scale test runs have been accomplished for speeds up to 20 mi/h. >

Roadway Electrification and Automation Technologies

This paper explains how the new technologies of roadway electrification and automation can be applied to help alleviate the severe transportation/environmental/energy problems facing our major metropolitan areas. The necessity of a complete system solution that encompasses these three problem areas simultaneously is emphasized. While the roadway‐electrification technology is targeted at the environmental and energy problems, the automatic steering and longitudinal control technologies serve to enhance mobility and safety in our urban motor transportation system. The vehicle control technologies offer the potential for dramatic increases in roadway capacity, which can significantly reduce travel times in congested urban regions. The significant synergism among the three technologies means that coordinated development and implementation will be significantly more beneficial than an approach that focuses on only one or two of the three technologies.

The development of the turntable combine harvester for improving turnability and operation efficiency

A turntable combine harvester was constructed based on theoretical computations and its performance in saving time for turning during harvesting operations was evaluated. Theoretical discussion was developed with a comparison between the prototype combine harvester and a commercial one from the view points of the total required time for completing the harvesting operation per unit area of the field with any shape ratio of the length to the width, and the total required distance which the combine travels. The cutting width, travelling speed, specification of the combine harvester and the shape ratio of the paddy field were chosen as the variables to estimate the total required time and distance. Both the time and distance were used to evaluate how the turntable combine harvester is superior to a commercial one. Automatic steering control was developed and tested in the experiment. The recommended shape and the function as a rice combine harvester were proposed.

最適自動操舵装置

This paper describes an Adaptive Automatic Steering Control System which has recently been developed by Nippon Kokan K.K. in cooperation with Yokogawa Hokushin Electric Corporation.The purpose of the system is to optimize both the course-keeping and course-changing ability of ship's autopilots under diverse operational and environmental conditions.The control systems for course-keeping and course-changing are distinctly different:(1) Course-Keeping ControlAn on-line parameter optimization procedure, based on the Hill-Climbing Method, is used in order to minimize the propulsion losses due to steering.(2) Course-Changing ControlModel Reference Adaptive Control (MRAC) is used in order to improve the transient characteristics during course changes, which makes it possible to assign the desired characteristics by a reference model.Full-scale sea trials have been carried out with this system, which show a great advantage for both economical steering ability and improved maneuverability.

The use of wave filter design in Kalman filter state estimation of the automatic steering problem of a tanker in a seaway

The problem of automatic steering control of a large tanker in a seaway is formulated within the framework of linear quadratic Gaussian (LQG) control theory. Wave disturbances are characterized by shaping filters, and Kalman filters are designed using these disturbance noise models. LQG controllers are designed to minimize a performance criterion commonly thought to be representative of propulsion losses due to steering. Performance of the controllers is determined by simulation results, which apply for deep water and are based on data from scale model tests.

Energy Losses Related to Automatic Steering of Ships in Waves—Part I: Losses Under Conventional Autopilot Control

Results are presented relating to energy losses due to ship steering in waves. Propulsion losses related to yawing and rudder activity of ships during open-seas course-keeping are evaluated. Two representative tankers of 250,000 and 400,000 dwt, and an 880 ft (268 m) long containership are examined, using hydrodynamic data resulting from captive model tests. The approach presented involves time-domain computer simulation studies of the yaw-sway-surge-rudder coupled motions of the ships. Evaluation of losses due to both yawing of the uncontrolled ship and those resulting from yawing and rudder effects in the automatically steered case are made. On the basis of the results presented it is shown that under the action of waves yawing of a ship results in significant energy losses. It is also shown that a substantial increase in energy losses occurs under automatic steering control with commonly accepted autopilot specifications.

Energy Losses due to Limit-Cycle Behavior of a Large Tanker Under Automatic Steering Control

The problem of limit-cycle behavior of a 250,000-dwt tanker in full-load and ballast conditions under automatic steering control in calm water is addressed. The approach presented involves digital computer time domain simulation studies of the yaw-sway-surge-rudder coupled motions of the ship emanating from nonlinearities in the steering system. It is shown that the amplitude of limit cycle in yaw remains, in general, within acceptable limits for open-seas navigation for a fairly wide range of autopilot bandwidths. Propulsion losses resulting from limit-cycle behavior in calm water are shown also to be, in general, small relative to the losses experienced in some conditions in waves. It is shown, however, that whereas increasing bandwidth reduces limit-cycle behavior in calm water, it can be expected to increase propulsion losses in heavy weather. The problem this poses in. design of steering gear controls and autopilot for this type of ship is discussed.

Automatic steering control of rubber-tired group rapid transit vehicles

Automatic steering control of rubber-tired group rapid transit vehicles

Steering Controller Design For Automated Guideway Transit Vehicles

The fundamental lateral performance capabilities of rubber-tired automated guideway transit (AGT) vehicles operating under automatic steering control on exclusive guideways are discussed. Control is achieved by steering the front wheels in response to signals derived from the position errors between the vehicle and a guideway-based reference containing random irregularities. Optimal control techniques are used to synthesize controllers which minimize a performance index consisting of mean square lateral acceleration and tracking error, defining a frontier which limits the performance of vehicles steered by a broad class of controllers. Simple single-sensor proportional steering controllers are found to achieve near-optimum performance for a typical AGT vehicle. The degradations in performance arising from dynamic lags in the steering actuator and operation at off-design speeds are shown.

Steering controller design for automated guideway transit vehicles

The fundamental lateral performance capabilities of rubber-tired automated guideway transit (AGT) vehicles operating under automatic steering control on exclusive guideways are discussed. Control is achieved by steering the front wheels in response to signals derived from the position errors between the vehicle and a guideway-based reference containing random irregularities. Optimal control techniques are used to synthesize controllers which minimize a performance index consisting of mean square lateral acceleration and tracking error, defining a frontier which limits the performance of steering controllers. Simple single-sensor proportional steering controllers are found to offer performance comparable to the optimum for a typical AGT vehicle. The degradations in performance arising from dynamic lags in the steering actuator and operation at off-design speeds are shown.

Swather Edge Guide Steering Control System

ABSTRACT A N automatic steering control A system has been developed for a self-propelled swather. A non-contact sensor placed at the front of the swather produces a signal which is used to control the position of the swather steering wheel. Field tests on various crops have indicated that the system can steer the swather with equal or better accuracy than a human operator.