scholarly journals Nonlinear Adaptive Line-of-Sight Path Following Control of Unmanned Aerial Vehicles considering Sideslip Amendment and System Constraints

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Zhengyang Cui ◽  
Yong Wang
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Finite Time ◽  
Control Strategies ◽  
Path Following ◽  
Fixed Time ◽  
Control Laws ◽  
Aerial Vehicles ◽  
Path Following Control ◽  
Heading Control ◽  
Cross Track

With growing worldwide interests in commercial, scientific, and military issues, there has been a corresponding rapid growth in demand for the development of unmanned aerial vehicles (UAVs) with more reliable and safer motion control abilities. This paper presents a new nonlinear path following scheme integrated with a heading control law for achieving accurate and reliable path following performance. Both backstepping and finite-time techniques are employed for developing the path following and heading control strategies capable of minimizing cross-track errors in finite-time with elegant transient performance, while the barrier Lyapunov function scheme is adopted to limit turning rates of the UAV for preventing it from capsizing which may be induced by overquick steering actions. A fixed-time nonlinear estimator, based on UAV kinematics, is designed for estimating the uncertainties with sideslip angles caused by external disturbances and inertial motions. To avoid the complicated calculation of derivatives of virtual control terms in backstepping, command filters and auxiliary systems are likewise introduced in the design of control laws. Extensive numerical simulation studies on a nonlinear UAV model are conducted to demonstrate the effectiveness of the proposed methodologies.

Robust fixed-time formation control for quadrotor unmanned aerial vehicles with directed topology

2021 ◽  
pp. 014233122110325
Author(s):  
Shikai Shao ◽  
Yuanjie Zhao ◽  
Xiaojing Wu
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Finite Time ◽  
Formation Control ◽  
Controller Design ◽  
Initial Conditions ◽  
Fixed Time ◽  
Settling Time ◽  
Lyapunov Theory ◽  
Directed Topology ◽  
Aerial Vehicles

Formation control is one of the key technologies for multiple unmanned aerial vehicles (UAVs). Compared with asymptotic or finite-time controllers, fixed-time controller can provide a guaranteed settling time, which does not depend on initial conditions and is an appealing property for controller design. Thus, robust fixed-time formation controller design for quadrotor UAVs under external disturbance and directed topology is investigated in this paper. A multi-variable super-twisting like integral sliding mode surface and a disturbance observer are respectively designed for position and attitude loops to guarantee robustness. Bi-limit homogeneity is utilized to design the whole closed-loop fixed-time controllers. By skillfully using bi-limit homogeneity technique and Lyapunov theory, the comprehensive stability of position and attitude loops is addressed. Finally, the multiple UAVs are utilized to track a pre-planned trajectory in 3D space and simulation results illustrate that the settling time can be reduced about 40% compared with finite-time controllers.

Straight Path Following Control for an Under-Actuated AUV

2014 ◽  
Vol 1030-1032 ◽  
pp. 1543-1549
Author(s):  
Yu Ling Ye
Keyword(s):  
Field Experiments ◽  
Path Following ◽  
Ocean Current ◽  
High Frequency Oscillation ◽  
Sideslip Angle ◽  
Path Following Control ◽  
Heading Control ◽  
Large Scope ◽  
Long Time ◽  
Cross Track

An engineering approach of path following control for the type of under-actuated AUV, such as REMUS, was proposed. The path following control was separated into 2 parts: heading guidance and heading control. The heading guidance was designed based on the cross-track error and line of sight guidance, and sideslip angle was proposed to compensate the disturbance of the ocean current. The turning criterion was proposed when the vehicle approach the waypoint. A PD control algorithm was presented to the heading control and its parameters variable with the speed. Simulation and field experiments data show that the vehicle follows the path accurately in the environment of current and different speed, and the vertical rudder keeps steady without large scope and high frequency oscillation which is fit for the long-time working AUV. Engineers can debug the parameters based on the experiment data efficiently for their explicit physical meaning.

scholarly journals Robust Output Path-Following Control of Marine Surface Vessels with Finite-Time LOS Guidance

2020 ◽  
Vol 8 (4) ◽  
pp. 275
Author(s):  
Lu Wang ◽  
Changkui Xu ◽  
Jianhua Cheng
Keyword(s):  
Output Feedback ◽  
Finite Time ◽  
Hierarchical Control ◽  
Path Following ◽  
Sideslip Angle ◽  
Disturbance Estimation ◽  
Surface Vessels ◽  
Path Following Control ◽  
Heading Control ◽  
Marine Surface

This paper proposes a finite-time output feedback methodology for the path-following task of marine surface vessels. First, a horizontal path-following model is established with unknown sideslip angle, unmeasured system state and system uncertainties. A hierarchical control structure is adopted to deal with the cascade property. For kinematics system design, a finite-time sideslip angle observer is first proposed, and thus the sideslip angle estimation is compensated in a nonlinear line-of-sight (LOS) guidance strategy to acquire finite-time convergence. For the heading control design, an extended state observer is introduced for the unmeasured state and equivalent disturbance estimation, based on which an output feedback backstepping approach is proposed for the desired tracking of command course angle. The global stability of the cascade system is analyzed. Simulation results validate the effectiveness of the proposed methodology.

Adaptive Finite Time Path-Following Control of Underactuated Surface Vehicle With Collision Avoidance

2019 ◽  
Vol 141 (12) ◽  
Author(s):  
Jawhar Ghommam ◽  
Lamia Iftekhar ◽  
Maarouf Saad
Keyword(s):  
Finite Time ◽  
Sliding Mode ◽  
Path Following ◽  
Control Laws ◽  
Finite Time Stability ◽  
Time Path ◽  
Path Following Control ◽  
Unknown Disturbances ◽  
Local Path ◽  
Surface Vessel

Abstract This paper considers the finite time path-following control problem for an underactuated surface vessel subject to parametric uncertainties, unknown disturbances, and involving input-control saturation. A finite time command filtered backstepping approach is adopted as the main control framework along with the first-order sliding mode differentiator introduced to compute the derivatives of virtual control laws, and the analytical computational burden in the backstepping control is reduced for the design of the control for the underactuated surface vessel. A rigorous proof of the finite time stability of the closed-loop system is derived by utilizing the Lyapunov method. Furthermore, in order to avoid obstacles, a local path replanning technique is designed based on a repulsive potential function that acts directly on the original desired path. The effectiveness of the proposed strategy is validated through numerical simulations.

Sign in / Sign up

Export Citation Format

Share Document