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

R. E. Reid; M. Youhanaie

doi:10.1115/1.3230907

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

Journal of Energy Resources Technology ◽

10.1115/1.3230907 ◽

1983 ◽

Vol 105 (2) ◽

pp. 222-229 ◽

Cited By ~ 1

Author(s):

R. E. Reid ◽

M. Youhanaie

Keyword(s):

Limit Cycle ◽

Computer Time ◽

Steering System ◽

Simulation Studies ◽

Time Domain Simulation ◽

Steering Control ◽

Wide Range ◽

Calm Water ◽

Automatic Steering ◽

Limit Cycle Behavior

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.

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

Journal of Energy Resources Technology ◽

10.1115/1.3230921 ◽

1983 ◽

Vol 105 (3) ◽

pp. 318-324 ◽

Cited By ~ 3

Author(s):

R. E. Reid ◽

B. C. Mears ◽

D. E. Griffin

Keyword(s):

Computer Simulation ◽

Time Domain ◽

Energy Losses ◽

Simulation Studies ◽

Steering Control ◽

Ship Steering ◽

Captive Model Tests ◽

Automatic Steering ◽

Computer Simulation Studies ◽

Hydrodynamic Data

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.

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Two-Stage Lane Keeping Control Algorithm for Lane Sensing Inaccuracy Handling

Volume 13: Transportation Systems ◽

10.1115/imece2013-65892 ◽

2013 ◽

Author(s):

Jin-Woo Lee ◽

Bakhtiar B. Litkouhi ◽

Hsun-Hsuan Huang

Keyword(s):

Steering System ◽

Poor Quality ◽

Smooth Transition ◽

Steering Control ◽

Two Stage ◽

Detection Range ◽

Active Safety Systems ◽

Automatic Steering ◽

The Subject ◽

Lane Keeping

The Lane Keeping Assist (LKA) system is a safety feature that applies an automatic steering torque to the vehicle steering system to keep the subject vehicle in its lane. Like many other active safety systems, the LKA systems may often experience a performance issue in real road situations. The common LKA performance issues are mainly due to poor quality of the front camera’s curvature data and sudden drops of camera’s detection range. To overcome these issues, this paper proposes a two-stage lane keeping control. In this approach, the LKA has two independent algorithms running with a coordination. In the coordination layer, the secondary lane keeping (LK) control has the authority to override the primary LK control if the primary LK fails to maintain the subject vehicle in the current lane due to the above issues. The key aspect of this system is the accurate timing of the secondary LK’s override over the primary LK. The coordination logic between the primary and the secondary LK control, and smooth transition between the controls are also important performance measures. The determination algorithm of the LK initiation and termination plays a key role in achieving the objectives of LKA fail handling. This paper describes these algorithms as well as the path planning and the steering control algorithms. Several vehicle tests were carried out on curved roads. The results show successful and smooth transition from the primary to the secondary LK layer.

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Limit cycle behavior of pipelined recursive digital filters

IEEE Transactions on Circuits and Systems II Analog and Digital Signal Processing ◽

10.1109/82.287006 ◽

1994 ◽

Vol 41 (5) ◽

pp. 351-355 ◽

Cited By ~ 5

Author(s):

Kyung Hi Chang ◽

W.G. Bliss

Keyword(s):

Limit Cycle ◽

Digital Filters ◽

Recursive Digital Filters ◽

Limit Cycle Behavior

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A novel path tracking approach considering safety of the intended functionality for autonomous vehicles

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211020535 ◽

2021 ◽

pp. 095440702110205

Author(s):

Huiran Wang ◽

Qidong Wang ◽

Wuwei Chen ◽

Linfeng Zhao ◽

Dongkui Tan

Keyword(s):

Autonomous Vehicles ◽

Autonomous Vehicle ◽

Coordinated Control ◽

Steering System ◽

Front Wheel ◽

Path Tracking ◽

Hierarchical Architecture ◽

Automatic Steering ◽

The Stability ◽

Control Layer

To reduce the adverse effect of the functional insufficiency of the steering system on the accuracy of path tracking, a path tracking approach considering safety of the intended functionality is proposed by coordinating automatic steering and differential braking in this paper. The proposed method adopts a hierarchical architecture consisting of a coordinated control layer and an execution control layer. In coordinated control layer, an extension controller considering functional insufficiency of the steering system, tire force characteristics and vehicle driving stability is proposed to determine the weight coefficients of automatic steering and the differential braking, and a model predictive controller is designed to calculate the desired front wheel angle and additional yaw moment. In execution control layer, a H∞ steering angle controller considering external disturbances and parameter uncertainty is designed to track desired front wheel angle, and a braking force distribution module is used to determine the wheel cylinder pressure of the controlled wheels. Both simulation and experiment results show that the proposed method can overcome the functional insufficiency of the steering system and improve the accuracy of path tracking while maintaining the stability of the autonomous vehicle.

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Differential steering-based electric vehicle lateral dynamics control with rollover consideration

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651819855810 ◽

2019 ◽

Vol 234 (3) ◽

pp. 338-348

Author(s):

Hui Jing ◽

Rongrong Wang ◽

Cong Li ◽

Jinxiang Wang

Keyword(s):

Electric Vehicles ◽

Measurement Problem ◽

Low Cost ◽

Steering System ◽

Front Wheel ◽

Steering Control ◽

Lateral Velocity ◽

Lateral Dynamics ◽

Vehicle Rollover ◽

Differential Steering

This article investigates the differential steering-based schema to control the lateral and rollover motions of the in-wheel motor-driven electric vehicles. Generated from the different torque of the front two wheels, the differential steering control schema will be activated to function the driver’s request when the regular steering system is in failure, thus avoiding dangerous consequences for in-wheel motor electric vehicles. On the contrary, when the vehicle is approaching rollover, the torque difference between the front two wheels will be decreased rapidly, resulting in failure of differential steering. Then, the vehicle rollover characteristic is also considered in the control system to enhance the efficiency of the differential steering. In addition, to handle the low cost measurement problem of the reference of front wheel steering angle and the lateral velocity, an [Formula: see text] observer-based control schema is presented to regulate the vehicle stability and handling performance, simultaneously. Finally, the simulation is performed based on the CarSim–Simulink platform, and the results validate the effectiveness of the proposed control schema.

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Modeling Unsteady Flow of a Lean Partially Premixed Flame on a Dry Low NOx Combustion System

Volume 1B: Combustion, Fuels and Emissions ◽

10.1115/gt2013-94969 ◽

2013 ◽

Author(s):

Salvatore Matarazzo ◽

Hannes Laget ◽

Evert Vanderhaegen ◽

Jim B. W. Kok

Keyword(s):

Gas Turbine ◽

Limit Cycle ◽

Gas Turbines ◽

Premixed Flame ◽

Computational Domain ◽

Pressure Oscillations ◽

Combustion Dynamics ◽

Partially Premixed ◽

Partially Premixed Flame ◽

Limit Cycle Behavior

The phenomenon of combustion dynamics (CD) is one of the most important operational challenges facing the gas turbine (GT) industry today. The Limousine project, a Marie Curie Initial Training network funded by the European Commission, focuses on the understanding of the limit cycle behavior of unstable pressure oscillations in gas turbines, and on the resulting mechanical vibrations and materials fatigue. In the framework of this project, a full transient CFD analysis for a Dry Low NOx combustor in a heavy duty gas turbine has been performed. The goal is to gain insight on the thermo-acoustic instability development mechanisms and limit cycle oscillations. The possibility to use numerical codes for complex industrial cases involving fuel staging, fluid-structure interaction, fuel quality variation and flexible operations has been also addressed. The unsteady U-RANS approach used to describe the high-swirled lean partially premixed flame is presented and the results on the flow characteristics as vortex core generation, vortex shedding, flame pulsation are commented on with respect to monitored parameters during operations of the GT units at Electrabel/GDF-SUEZ sites. The time domain pressure oscillations show limit cycle behavior. By means of Fourier analysis, the coupling frequencies caused by the thermo-acoustic feedback between the acoustic resonances of the chamber and the flame heat release has been detected. The possibility to reduce the computational domain to speed up computations, as done in other works in literature, has been investigated.

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A fault tolerant control design for automatic steering control of ground vehicles

2012 IEEE International Conference on Control Applications ◽

10.1109/cca.2012.6402714 ◽

2012 ◽

Cited By ~ 3

Author(s):

Afef Fekih ◽

Shankar R. Seelem

Keyword(s):

Fault Tolerant ◽

Control Design ◽

Fault Tolerant Control ◽

Ground Vehicles ◽

Steering Control ◽

Automatic Steering

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Limit-Cycle Analysis of Three-Dimensional Flexible Shaft/Rigid Rotor/Autobalancer System With Symmetric Rigid Supports

Journal of Vibration and Acoustics ◽

10.1115/1.4032718 ◽

2016 ◽

Vol 138 (3) ◽

Cited By ~ 5

Author(s):

DaeYi Jung ◽

H. A. DeSmidt

Keyword(s):

Limit Cycle ◽

Three Dimensional ◽

Design Parameters ◽

Rigid Rotor ◽

Modal Shape ◽

Flexible Shaft ◽

Flexible Mode ◽

Automatic Balancing ◽

Rigid Supports ◽

Limit Cycle Behavior

In recent years, there has been much interest in the use of automatic balancing devices (ABD) in rotating machinery. Autobalancers consist of several freely moving eccentric balancing masses mounted on the rotor, which, at certain operating speeds, act to cancel rotor imbalance. This “automatic balancing” phenomenon occurs as a result of nonlinear dynamic interactions between the balancer and rotor wherein the balancer masses naturally synchronize with the rotor with appropriate phase to cancel the imbalance. However, due to inherent nonlinearity of the autobalancer, the potential for other undesirable nonsynchronous limit-cycle behavior exists. In such situations, the balancer masses do not reach their desired synchronous balanced positions resulting in increased rotor vibration. To explore this nonsynchronous behavior of ABD, the unstable limit-cycle analysis of three-dimensional (3D) flexible shaft/rigid rotor/ABD/rigid supports described by the modal coordinates has been investigated here. Essentially, this paper presents an approximate harmonic analytical solution to describe the limit-cycle behavior of ABD–rotor system interacting with flexible shaft, which has not been fully considered by ABD researchers. The modal shape of flexible shaft is determined by using well-known fixed–fixed boundary condition due to symmetric rigid supports. Here, the whirl speed of the ABD balancer masses is determined via the solution of a nonlinear characteristic equation. Also, based upon the analytical limit-cycle solutions, the limit-cycle stability of three primary design parameters for ABD is assessed via a perturbation and Floquet analysis: the size of ABD balancer mass, the ABD viscous damping, and the relative axial location of ABD to the imbalance rotor along the shaft. The coexistence of the stable balanced synchronous condition and undesirable nonsynchronous limit-cycle is also studied. It is found that for certain combinations of ABD parameters and rotor speeds, the nonsynchronous limit-cycle can be made unstable, thus guaranteeing asymptotic stability of the synchronous balanced condition at the supercritical shaft speeds between each flexible mode. Finally, the analysis is validated through numerical simulation. The findings in this paper yield important insights for researchers wishing to utilize ABD in flexible shaft/rigid rotor systems and limit-cycle mitigation.

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