A proportional derivative sliding mode control for an overactuated quadcopter

Abstract

Traditional quadcopters suffer from their intrinsic underactuation, which prevents them from tracking arbitrary trajectories. In this study, a step-by-step mathematical modeling of a tilt rotor quadcopter, i.e. a quadcopter with all its four rotors are allowed to be tilted independently around their arms’ extension, is derived. The tilting mechanism converts the classical quadcopter to an overactuated flying vehicle that has full control over its states. The nonlinear dynamical model is derived based on the Newton–Euler formalization. A novel trajectory tracking control scheme is then proposed and developed. The proposed controller combines the proportional derivative linear controller with the nonlinear sliding mode controller. In order to reduce the chattering effect of the sliding mode controller, the discontinuous Signum switching function is replaced by a continuous sigmoidal function. The controller parameters are then tuned with the aid of genetic algorithm as an optimization tool. The genetic algorithm objective function is set so as to get the best step response characteristics. A simulation based analysis is used to proof the system and controller capability in following complex trajectories. Finally, the proposed controller robustness and effectiveness are analyzed. The simulation test results reveal the validity and feasibility of the proportional derivative sliding mode controller. The proposed controller also performed well in the face of modeling imprecision, sensor noise, and external disturbances.

Feedforward neural network emulation of a PID continuous-time controller for quadcopter attitude digital control

“…A process is usually controlled by a standard controller (PID and RST) [21], [22]. An identifier neural network may approximatively learn the controller's inputs and outputs offline as we see in Figure 2.…”

“…QUADCOPTER MODELING Modeling is the first and most significant step in designing an object's control strategy since it helps comprehend body specifications and constraints that limit control command application. Despite its mechanical symmetry, a quadcopter is a non-linear model, for this, the Newton-Euler method was used to model quadcopter [21].…”

Tri-Copter UAV With Individually Tilted Main Wings for Flight Maneuvers

“…Telemetry ground module and telemetry air module are connected by serial communication. [42], [43] that can be used to transfer linear speed and angular speed to the global frame are as follows…”

Trajectory tracking of under-actuated quadcopter using Lyapunov-based optimum adaptive controller

“…To this date, a number of efficient control approaches have been successfully applied on aerospace systems. [2][3][4][5][6][7][8][9] For example, linear controllers such as proportionalintegral-derivative (PID) 10,11 and linear quadratic regulator [12][13][14] and nonlinear control approaches such as fuzzy-adaptive extended Kalman filter, 15 model predictive, 16 θ-D-based nonlinear tracking, 17 immersion and invariance-based adaptive theory, 18 nonlinear L 1 adaptive control, 19 sliding mode controller, 20,21 feedback linearization, 22,23 and backstepping [24][25][26] have been investigated for aerospace systems with fully known dynamics. What is more, several control methods have been developed to tackle the uncertain dynamic model of a dynamic system.…”