Yaw Motion Control Research Articles

Pitch and yaw motion control of 2 DoF helicopter subjected to faults using sliding-mode control

Pitch and yaw motion control of 2 DoF helicopter subjected to faults using sliding-mode control

Motion Control of Capsule Robot Based on Adaptive Magnetic Levitation Using Electromagnetic Coil

In view of the magnetically actuated capsule robot applications in diagnoses of human stomach disease, the challenges that are associated with degrees-of-freedom (DOF), environmental adaptability, and the size of the entire system must be addressed. In this study, a new electromagnetic coil system that is based on adaptive magnetic levitation is presented; it is mainly composed of an independent orientation control electromagnetic coil and a magnetic levitation control electromagnetic coil. The system is designed to perform motion control of the capsule, including 3-DOF levitating translational motion control, and pitch and yaw motion control in levitation. In this manner, it compensates for the lack of previous magnetic levitation systems that were based on electromagnetic coils for the control of the tilt angle of the capsule. With torque-based actuation control, the tilt angle of the capsule can be controlled continuously with an angle increment of no more than 2 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{\circ}$</tex-math> </inline-formula> (within 30 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{\circ}$</tex-math> </inline-formula> ) during levitation. The capsule under the magnetic levitation control, which is based on the fuzzy proportional-integral -derivative controller, can maintain the stability of levitation; the error between the actual capsule position and the required position did not exceed 0.1 mm when the capsule was out of water or completely immersed in it. Moreover, the experiment of the capsule levitating from air to water further verifies the adaptability of the system with regard to the environment; this provides a new examination method for capsule endoscopy. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —This work is caused by the motion manipulation problem of a magnetically driven capsule robot. Most of the existing magnetically driven capsule robots use a rolling or sliding method that fits tightly against the stomach wall, and these forms of motion make it possible to risk missing diagnoses in the examination of gastric diseases, and the maneuverability limits its further application. This paper proposes an adaptive control strategy for a magnetically driven capsule robot based on magnetic levitation motion. It allows the magnetically driven capsule robot to levitate to any position in the stomach for photography and observation without external mechanical support, and this levitation motion is sufficiently stable. In addition, the proposed capsule robot has independent orientation and position control, which has the potential to achieve automated inspection.

A MAS-Based Hierarchical Architecture for the Cooperation Control of Connected and Automated Vehicles

Complex traffic scenarios pose a challenge to the cooperation control of connected and automated vehicles (CAVs). Conventional platoon control or advanced driver-assistance systems only provide an isolated solution due to their inadequacies in systematic perspective. To this end, a multi-agent system (MAS) based distributed control architecture together with a hierarchical controller is proposed for the CAVs cooperation control system. The upper layer considers the potential states of a CAV in the platoon evolution (i.e., vehicle-cruising maneuver and vehicle-following maneuver) and elaborates the transition rules for discrete maneuvering behaviors. The lower layer includes the corresponding motion controller for each CAV. Artificial potential field (APF) combined with the distributed model predictive control algorithm is adopted to realize the integrated longitudinal, lateral and yaw motion control of CAVs. Next, inspired by the Pareto-optimal method for tackling the MAS-cooperation system, an optimal solution strategy is introduced to solve the CAVs cooperation problem from the viewpoint of the control theory. Furthermore, multi-constraints are designed to ensure a safety inter-vehicle spacing between CAVs, while the vehicle stability can also be guaranteed. The simulation results demonstrate that the MAS-based hierarchical control architecture can effectively handle the cooperation control of CAVs in the typical traffic scenarios. The real-time implementation of the proposed controller also proves the feasibility.

PSO-Based Variable Parameter Linear Quadratic Regulator for Articulated Vehicles Snaking Oscillation Yaw Motion Control

In this paper, the seven degrees of freedom (DOF) nonlinear system model of articulated vehicles, including the vehicle dynamics model, tire and hydraulic steering system model, and the linearized ideal reference model, is constructed. A layered stability controller for the articulated vehicle is built. The particle swarm optimization (PSO)-based variable parameter linear quadratic regulator (LQR) for the upper-level yaw torque controller and the lower-level torque distributor based on the principle of the minimum tire utilization are established. The effectiveness of the LQR upper-level yaw torque controller for an articulated vehicle at different speeds and control references are compared and analyzed through feedforward and feedback control. We optimize the parameters in the LQR controller using PSO and verify the improvement in the controller’s performance with optimized parameters. Overall, the effect of front and rear-integrated control is best, followed by rear-based and front-based control. The PSO algorithm to optimize the LQR controller parameters for snaking oscillation control is effective.

Integrated Adaptive Steering Stability Control for Ground Vehicle with Actuator Saturations

During a steering manoeuvre in a ground vehicle, both yaw motion and roll motion can occur simultaneously, and their dynamics can be coupled, as the roll motion is generalized directly from the tires’ lateral force under steering. Hence, it is of significance to analyze them as an integrated plant in the vehicle steering stability control problem. Furthermore, the actuator saturation of yaw control cannot be neglected, as vehicles often steer at a high velocity or on low-friction roads. In this paper, an integrated steering dynamics model is established considering the coupling between the roll motion and lateral motion, then a novel nonlinear adaptive controller is proposed to stabilize the steering motion considering the actuator saturation of yaw motion control. Simulation results indicate that the designed integrated controller is effective in improving the performance of both the yaw rate tracking error and ride comfort taking into account vehicle parameter uncertainties and actuator saturation; the steering stability of ground vehicles can consequently be guaranteed.

The cascade optimal control of steer by wire system using hardware in the loop simulations

This paper aims to further improve the performance of the control system on the steer by wire (SbW) of vehicle steering system, by presenting the development of optimal control system strategy for lateral motion and yaw motion which is arranged in a cascade so that the vehicle can always be maintained on the desired trajectory. The control system strategy to be developed is fuzzy logic control (FLC) as a lateral motion control and proportional integral derivative (PID) control as a yaw motion control, and to obtain an optimal control system, the modified-quantum particle swarm optimization (MQPSO) optimization method is used. The simulations are carried out using hardware in the loop simulations (HILS) which involve hardware, namely; motor stepper actuator and rotary encoder to determine and monitor the direction of the front wheels which are applied to the vehicle dynamics model in a real time. HILS test results show that vehicle movement can be maintained according to the desired trajectory (double lane change) with an average continues-root mean square (C-RMS) error of 0.015366 for lateral motion and 0.014967 for yaw motion, the average C-RMS error is greater 23.75% for lateral motion and 28.18% for yaw motion against the results of the software in the loop simulations (SILS) test.

An Innovative Pose Control Mechanism for a Small Rudderless Underwater Vehicle

Current and conventional pose (position and orientation) control of a small underwater vehicle is achieved by using rudders (yaw motion control) and elevators (pitch motion control), but these suffer from non-linear, indirect and complex control issues. This paper proposes an innovative pose control mechanism for small underwater vehicles. The mass shifter mechanism is designed and fabricated to control pitch and yaw motion with a single propeller only. The center of mass of the underwater vehicle is altered by moving a pair of counterweights on fixed tracks. The pitch and yaw are achieved by controlling the position of the counterweight pairs. The proposed system is designed, fabricated and tested in a real underwater environment for proof-of-concept. The result shows a simpler, more efficient and more effective pose control mechanism than conventional technology.

Fault-Tolerant Control of Multirotor UAVs by Control Variable Elimination

This article presents to develop a fault-tolerant control (FTC) to cope with defective thrust systems in multirotor unmanned aerial vehicles (UAV). Faults can occur for a number of reasons in flight, including defective motor performance and damaged propellers. The faults deform both the thrust and torque outputs that could result in the UAV crashing and causing secondary accidents. The FTC method in the article is developed to reconfigure thrust systems using the optimal control when significant degrees of failure occur in a number of defective motors. Orientation control could be abandoned to maintain the controllability of altitude when the control output loss cannot be compensated for because of motor saturation. Specifically, yaw motion control is sacrificed, resulting in a rapid rotation and divergence of position control. The divergence can be resolved by a feed forward control loop on the roll and pitch angles. Both simulations and experiments are implemented to demonstrate the performance of the FTC. The results indicate that the proposed FTC can be implemented to minimize accidents from failures of main thrust systems.

An integrated control strategy of path following and lateral motion stabilization for autonomous distributed drive electric vehicles

This article proposes an integrated control strategy of autonomous distributed drive electric vehicles. First, to handle the multi-constraints and integrated problem of path following and the yaw motion control, a model predictive control technique is applied to determine optimal front wheels’ steering angle and external yaw moment synthetically and synchronously. For ensuring the desired path-tracking performance and vehicle lateral stability, a series of imperative state constraints and control references are transferred in the form of a matrix and imposed into the rolling optimization mechanism of model predictive control, where the detailed derivation is also illustrated and analyzed. Then, the quadratic programming algorithm is employed to optimize and distribute each in-wheel motor’s torque output. Finally, numerical simulation validations are carried out and analyzed in depth by comparing with a linear quadratic regulator–based strategy, proving the effectiveness and control efficacy of the proposed strategy.

Rudder Roll Damping Autopilot Using Dual Extended Kalman Filter–Trained Neural Networks for Ships in Waves

The roll motions of ships advancing in heavy seas have severe impacts on the safety of crews, vessels, and cargoes; thus, it must be damped. This study presents the design of a rudder roll damping autopilot by utilizing the dual extended Kalman filter (DEKF)–trained radial basis function neural networks (RBFNN) for the surface vessels. The autopilot system constitutes the roll reduction controller and the yaw motion controller implemented in parallel. After analyzing the advantages of the DEKF-trained RBFNN control method theoretically, the ship’s nonlinear model with environmental disturbances was employed to verify the performance of the proposed stabilization system. Different sailing scenarios were conducted to investigate the motion responses of the ship in waves. The results demonstrate that the DEKF RBFNN–based control system is efficient and practical in reducing roll motions and following the path for the ship sailing in waves only through rudder actions.

Oscillatory Yaw Motion Control for Hydraulic Power Steering Articulated Vehicles Considering the Influence of Varying Bulk Modulus

In this investigation, a detailed hydraulic steering system of articulated steer vehicles (ASVs) and a 12-DOF ASV model are developed for vehicle dynamics performance research. The real-time changing characteristic of oil bulk modulus is considered. Field test and multibody dynamics model by Adams/View software are compared with the established mathematical model, respectively, to verify the correctness of the model at low speed and high speed. The snaking and oscillatory area is confirmed to reveal the influence of varying bulk modulus on the stability of ASV. To improve the stability of ASV, the direct yaw moment control system and driving force distribution system are designed with the application of the optimal control theory. The upper level controller calculates the expected yaw moment by feedforward and feedback compensatory strategies. Different from zero-sideslip control in most studies, an Ackermann-based sideslip angle is used for feedforward compensatory gain derivation and reference model design. The lower level controller distributes the driving force for each wheel aiming at the optimal utilization rate of tires. High-speed weave test by sinusoidally steering for loaded ASV is simulated to verify the effectiveness of the control algorithms.

Integral backstepping control for trajectory and yaw motion tracking of quadrotors

SUMMARYThis work presents a novel trajectory tracking, hovering, and yaw motion control for quadrotors subject to unknown modeling uncertainties and disturbances. Nonlinear equations of motion are used to model the quadrotor's motion without any simplifying assumptions. An integral backstepping control is developed by defining the tracking errors, their integral, and their first through third time derivatives as the system states. The resulting surge force and roll and pitch moments are shown to asymptotically stabilize the error states subject to bounded disturbances and modeling uncertainties. Similarly, a yaw moment is derived through integral backstepping that simultaneously stabilizes yaw motion errors. The controller performance in simultaneous trajectory and yaw motion tracking is verified through both simulations and experiments.

Vehicle motion control under equality and inequality constraints: a diffeomorphism approach

This study addresses the problem of vehicle lateral and yaw motion control when both equality and inequality (i.e., bilateral and unilateral) constraints are involved. By using the Udwadia–Kalaba approach, the explicit equation of vehicle motion with equality constraints is established, and the corresponding control inputs can be obtained from the equation. The equality constraints aim to render the vehicle to move along the desired trajectory. However, as the initial conditions of vehicle motion may take values leading the vehicle to violate the road-bound lines, it is necessary to impose an additional constraint to constrain the vehicle to move within the road-bound lines, which is an inequality constraint. As the inequality constraint cannot be handled by the original Udwadia–Kalaba approach, a creative diffeomorphism approach is proposed to integrate the inequality constraint into the equality constraints, and thus it creatively enables the Udwadia–Kalaba approach to deal with both equality and inequality constraints. By solving the equation established based on the Udwadia–Kalaba approach and diffeomorphism approach, the control inputs that can render the vehicle to move along the desired trajectory without violating the road-bound lines are obtained. The effectiveness of the proposed method is demonstrated by numerical simulation results.

Design and Analysis of a New Torque Vectoring System with a Ravigneaux Gearset for Vehicle Applications

The purpose of this research is to develop a new torque vectoring differential (TVD) for vehicle applications and investigate its effect on vehicle dynamic control. TVD is a technology that is able to distribute the engine torque to the left and right driving wheels at different ratios so that the yaw motion control can be realized. Attention has been paid to this technology in recent years because of its potential to improve the vehicle performance and driving safety. In this study, a new TVD design with a Ravigneaux gearset was developed. This new design is able to use only one pair of gearsets to generate two different speed ratios, and the weight and volume of the system can be reduced. To execute the research, current TVD designs were analyzed and their design principles were clarified. Next, a new TVD design with Ravigneaux gearset was proposed. Then the connecting manner and the gear ratio of the Ravigneaux gearset were discussed. The dynamic equation of the system was then derived and the operation of the system was simulated in a MATLAB program. Further simulation was performed with a vehicle dynamic model in SimulationX to demonstrate the effect of the new system. The results of this study show the potential of building a new TVD with a Ravigneaux gearset and can be helpful for further system development.

Yaw Motion Control of Electromagnetic Guidance System for High-Speed Maglev Vehicles

In an attractive-type high-speed magnetic levitation (maglev) train, separate electromagnets are used for lateral guidance. For the guidance system, a U-shaped electromagnet that uses transverse flux has been designed and analyzed. Electromagnets counterbalance centrifugal forces during curving as well as under all operating conditions so that the clearances between on-board magnets and the guideway surface can be maintained within an allowable range. Because of the rigidity of the bogie, coupling effects exist among the magnets that are controlled independently. This study incorporates bogie yaw motion into control law for adjusting the voltages applied to magnets to provide constant clearance control. The effects of bogie yaw motion on guidance control performance are investigated experimentally using a full-scale vehicle.

Lyapunov exponents-based stability analysis and integrated control of rollover mitigation and yaw stabilisation of ground vehicles

Yaw stabilisation and rollover prevention are two key factors in safety of vehicles. Designing a controller that can address both of the safety concerns and evaluating the performance of such a control system using a proper stability analysis tool is of interest. The complexities in dynamics of vehicles, such as tyre dynamics, make the stability analysis of such systems more challenging. In addition, maintaining both of the above objectives, the yaw motion control and rollover mitigation, is contradictory when a vehicle experiences high lateral accelerations. In this research, a T-S fuzzy controller is proposed which prioritises the concern that must be addressed at each time instant based on the state of the vehicle. The controller compromises between the two contradictory objectives of tracking a desired value for the yaw rate and maintaining the rollover index within a limit to ensure wheel lift-off does not occur. A novel method using the concept of Lyapunov exponents is employed to perform system and structural stability analysis. Results of the stability analysis together with simulations demonstrate the advantages of the proposed controller.

차량 전복 방지를 위한 롤 및 요 운동 제어기의 성능 비교

This article presents a comparison among several yaw and roll motion controllers for vehicle rollover prevention. In the previous research, yaw and roll motion controllers can be independently designed for rollover prevention. Following this idea, several yaw and roll motion controllers are designed and compared in terms of rollover prevention. For the yaw motion control, PID, LQR, SMC (Sliding Mode Control) and TDC (Time-Delay Control) are adopted. For the roll motion control, LQR, LQ SOF (Static Output Feedback) control, PID, and SMC are adopted. To compare the performance of each controller, simulation is performed on a vehicle simulation package, CarSim<TEX>$^{(R)}$</TEX>. From simulation, TDC and LQ SOF are the best for yaw and roll motion control, respectively.

Semi-active H∞ control of high-speed railway vehicle suspension with magnetorheological dampers

In this paper, semi-active H∞ control with magnetorheological (MR) dampers for railway vehicle suspension systems to improve the lateral ride quality is investigated. The proposed semi-active controller is composed of a H∞ controller as the system controller and an adaptive neuro-fuzzy inference system (ANFIS) inverse MR damper model as the damper controller. First, a 17-degree-of-freedom model for a full-scale railway vehicle is developed and the random track irregularities are modelled. Then a modified Bouc–Wen model is built to characterise the forward dynamic characteristics of the MR damper and an inverse MR damper model is built with the ANFIS technique. Furthermore, a H∞ controller composed of a yaw motion controller and a rolling pendulum motion (lateral motion+roll motion) controller is established. By integrating the H∞ controller with the ANFIS inverse model, a semi-active H∞ controller for the railway vehicle is finally proposed. Simulation results indicate that the proposed semi-active suspension system possesses better attenuation ability for the vibrations of the car body than the passive suspension system.

An investigation into the structures of linear quadratic controllers for vehicle rollover prevention

This paper presents a comparison between structures of linear quadratic controllers for vehicle rollover prevention. Three types of linear quadratic controller, namely a linear quadratic regulator, a structured controller and a separated controller, are compared. These controllers can control yaw and roll motions. The point is whether the yaw motion and the roll motion can be controlled separately for effective rollover prevention. The separation between a yaw motion controller and a roll motion controller is captured by using structured and separated controllers. Simulations on the vehicle simulation software CarSim® are performed to show that a structured controller and a separated controller are equivalent to a linear quadratic regulator for vehicle rollover prevention.

Variable field-of-view machine vision based row guidance of an agricultural robot

A novel variable field-of-view machine vision method was developed allowing an agricultural robot to navigate between rows in cornfields. The machine vision hardware consisted of a camera with pitch and yaw motion control. Guidance lines were detected using an image-processing algorithm, employing morphological features in a far, near and lateral field of view, and the robot was guided along these lines using fuzzy logic control.The method was tested while the vehicle successfully traveled through a distance of 30m towards the end of a crop row in three replications. To evaluate the guidance performance, RTK-GPS data were collected, showing a maximum guidance error of 15.8mm and stable navigational behavior.