Vehicle dynamics

About: Vehicle dynamics is a research topic. Over the lifetime, 12909 publications have been published within this topic receiving 204091 citations.

A Novel Null-Space-Based UAV Trajectory Tracking Controller With Collision Avoidance

Abstract: A new trajectory tracking controller with collision avoidance is proposed in this paper for unmanned aerial vehicle (UAV) navigation. A positive potential function is designed to take into account the movement of obstacles. Thus, the controller with potential function guarantees that the UAV moves through areas of potentials close to zero to ensure safe navigation in dynamic and unknown environments. Such a controller was designed with hierarchical objectives using a behavioral-based approach. A null-space-based controller is adopted, whose main objective is to ensure that the collision avoidance is achieved, whereas other objectives are projected onto the null space. Collision avoidance and trajectory tracking controllers generate reference velocities sent to a dynamic compensator to guarantee the tracking of such velocities, thus characterizing a cascade controller. Stability of the entire closed-loop nonlinear system is demonstrated through Lyapunov's theory. A low-cost indoor framework with just one RGB-D sensor, which is a combination of a RGB (red-green-blue) camera with a depth sensor based on infrared light was used to estimate the positions of the UAV and obstacles. Simulation and experiments are run using a Parrot AR.Drone quadrotor and considering a person as a dynamic obstacle for an AR.Drone quadrotor, and some of their results are reported to validate the proposed controller.

Gain-scheduled controller design based on descriptor representation of LPV systems: application to flight vehicle control

Abstract: This paper is concerned with a synthesis method of gain-scheduled controllers based on descriptor representations of LPV systems and its application to design of flight vehicle control. By representing a linear parameter-varying system in the descriptor form, parameter-dependent LMI to seek a gain-scheduled controller are formulated so that they have simple structure with respect to the parameter. A gain-scheduled controller is computed directly via an explicit formula in terms of the variable of LMI for LPV descriptor systems. This synthesis procedure is applied to design of flight vehicle control to satisfy multiple control specifications under large variation of the airspeed. Dynamics of the vehicle is modeled as an LPV descriptor system and a gain-scheduled controller is obtained by solving the proposed LMI. Control performance is improved by employing parameter-dependent Lyapunov matrices.

Fixed-Time Control With Uncertainty and Measurement Noise Suppression for Hypersonic Vehicles via Augmented Sliding Mode Observers

Abstract: Uncertainty and measurement noise are main obstacles that limit the tracking control performances of flexible air-breathing hypersonic vehicles (FAHVs). In this article, we propose a novel fixed-time convergent nonsmooth backstepping control scheme for FAHV via augmented sliding mode observers (ASMOs) to overcome these obstacles. The ASMOs are first designed for the FAHV dynamics by employing the measured states corrupted by noises as inputs. On one hand, the ASMOs can simultaneously estimate the uncertainties and filter out the measurement noises. On the other hand, the observation error of each ASMO can be convergent within a fixed time independent of its initial observation error. Then, based on the estimation results, the altitude and velocity tracking controllers are developed by using fixed-time nonsmooth backstepping technique. Afterwards, a Lyapunov-based stability analysis is given to illustrate the fixed-time convergence of the closed-loop signals of the FAHV control system. Finally, comparative simulations are conducted to illustrate the superiority of the proposed control scheme.

Yaw rate and side-slip control considering vehicle longitudinal dynamics

Abstract: Most conventional vehicle stability controllers operate on the basis of many simplifying assumptions, such as a small steering wheel angle, constant longitudinal velocity and a small side-slip angle. This paper presents a new approach for controlling the yaw rate and side-slip of a vehicle without neglecting its longitudinal dynamics and without making simplifying assumptions about its motion. A sliding-mode controller is used to develop a differential braking controller for tracking a desired vehicle yaw rate for a given steering wheel angle, while keeping the vehicle’s side-slip angle as small as possible. The trade-off that exists between yaw rate and side-slip control is described. Conventional and proposed algorithms are presented, and the effectiveness of the proposed controller is investigated using a seven-degree-of-freedom vehicle dynamics model. The simulation results demonstrate that the proposed controller is more effective than the conventional one.

A Potential Field Approach-Based Trajectory Control for Autonomous Electric Vehicles With In-Wheel Motors

Abstract: The studies on the autonomous electric vehicle are quite attractive due to fewer human-induced errors and improved safety in recent years. Extensive research has been done on the autonomous steering control of the mobile robot, but study on the on-road autonomous electric vehicle is still limited. This paper proposes a potential field method to achieve the trajectory control of the autonomous electric vehicle with in-wheel motors. Instead of strictly following a desired path, this method can form a steering corridor with a desired tracking error tolerance and the vehicle can be steered smoothly with less control effort. In this paper, the innovative potential filed function is presented first to determine the desired vehicle yaw angle. Then, according to this desired yaw angle, a two-level trajectory controller is proposed to achieve the trajectory control. Simulation results are shown to prove that this suggested trajectory controller can successfully control the vehicle to move within the desired road boundary and improve the handling and stability performance of the vehicle.