Nonlinear control of a quadrotor micro-UAV using feedback-linearization

Abstract

Four-rotor micro aerial robots, so called quadrotor UAVs, are one of the most preferred type of unmanned aerial vehicles for near-area surveillance and exploration both in military and commercial in-and outdoor applications. The reason is the very easy construction and steering principle using four rotors in a cross configuration. However, stabilizing control and guidance of these vehicles is a difficult task because of the nonlinear dynamic behavior. In addition, the small payload and the reduced processing power of the onboard electronics are further limitations for any control system implementation. This paper describes the development of a nonlinear vehicle control system based on a decomposition into a nested structure and feedback linearization which can be implemented on an embedded microcontroller. Some first simulation results underline the performance of this new control approach for the current realization.

Flexible Heuristic Dynamic Programming for Reinforcement Learning in Quad-Rotors

“…The results of the RL controller are compared to a feedback-linearization controller from [71], which acts as a baseline. One simulation run for the feedback-linearization controller has been depicted in Figure 2.12.…”

Receding Horizon Control in Dynamic Environments from Temporal Logic Specifications

“…3) are based on (1) input-output linearization for the quadrotor dynamics [16], and (2) construction of multi-affine vector fields for control-to-facet and invariance in rectangles [2,9]. Due to space limitations, the details are omitted.…”

“…The outer loop first calculates the desired acceleration based on proportional-integral feedback with respect to the velocity setpoint, and then transforms the control outputs into a desired attitude. A feedback linearization approach is used to find the desired attitude by solving the dynamics equations for an orientation and thrust that produces the appropriate motion, while accounting for the non-linear dynamics in the model [16]. The desired attitude is then used as a reference for the inner control loop, designed to stabilize the attitude.…”

Nonlinear tracking and landing controller for quadrotor aerial robots

“…The attitude of the quadrotor is given by the roll, pitch and yaw angle, forming the vector Ω Ω Ω T = (φ, θ, ψ), while the position of the vehicle in the inertial frame is given by the position vector r r r T = (x, y, z). The dynamic model of the quadrotor can be derived by applying the laws of conservation of momentum and angular momentum, taking the applied forces and torques into account (see [6]). The thrust force generated by rotor i, i = 1, 2, 3, 4 is…”

“…Many of the proposed control systems are based on a linearized model and conventional PID-or state space control while other approaches apply sliding-mode, H ∞ or SDRE control [4], [5]. Recently, a new nonlinear control algorithm has been proposed by the author which is based upon a decomposition of the overall controller into a nested structure of velocity and attitude control, see [6]. The controller has the advantage of an easy implementation and proven stability while taking the nonlinearities of the dynamics directly into account.…”