Improved Altitude Control Algorithm for Quadcopter Unmanned Aerial Vehicles

Abstract

Quadcopter unmanned aerial vehicles continue to play important roles in several applications and the improvement of their control performance has been explored in a great number of studies. In this paper, we present an altitude control algorithm for quadcopters that consists of a combination of nonlinear and linear controllers. The smooth transition between the nonlinear and linear modes are guaranteed through controller gains that are obtained based on mathematical analysis. The proposed controller takes advantage and addresses some known shortcomings of the conventional proportional–integral–derivative control method. The algorithm is simple to implement, and we prove its stability through the Lyapunov theory. By prescribing certain flight conditions, we use numerical simulations to compare the control performance of our control method to that of a conventional proportional–derivative–integral approach. Furthermore, we use a DJI-F450 drone equipped with a laser ranging sensor as the experimental quadcopter platform to evaluate the performance of our new controller in real flight conditions. Numerical simulation and experimental results demonstrate the effectiveness of the proposed algorithm.

Autonomous Quadcopter Precision Landing Onto a Heaving Platform: New Method and Experiment

“…In this section, we briefly present the quadcopter dynamics model as it was clearly introduced and verified in many previous studies [30], [33], [34]. Figure 1 illustrates the quadcopter configuration.…”

“…The proposed altitude controller gains are listed in Table 3. It is worth noting that the horizontal position controller is designed using our multi-mode controller already presented in our previous work (see [33]), and the attitude controllers are designed using the PID control law. Since these controllers are beyond the scope of this paper, they will not be presented in this section.…”

Robust Backstepping Trajectory Tracking Control of a Quadrotor with Input Saturation via Extended State Observer

“…In this section, we briefly present the quadrotor dynamics model, as it was clearly introduced and verified in many previous studies [34,43,50,51]. Figure 1 illustrates the quadrotor configuration.…”

Quadcopter Adaptive Trajectory Tracking Control: A New Approach via Backstepping Technique

“…It is undeniable that the conventional proportional-integral-derivative (PID) control is still widely used in a variety of many applications all over the world because it is uncomplicated to be applied and acceptably meet given requirements in many studies [7][8][9][10][11][12][13][14][15]. The authors [16][17][18][19] presented the use of a multi-loop control scheme (i.e., inner-loop and outer-loop) to control quadcopters in specific applications.…”