Geometry-aware Compensation Scheme for Morphing Drones

Abstract

Recent studies have shown that enabling drones to change their morphology in flight can significantly increase their versatility in different tasks. In this paper, we investigate the aerodynamic effects caused by the partial overlap between the propellers and the main body of a morphing quadrotor during flight. We experimentally characterize such effects and design a morphology-aware control scheme to compensate them. We demonstrate the effectiveness of our approach by deploying the compensation scheme on a quadrotor that can fold its arms around the main body, comparing it against the same controller without the compensation scheme. Experimental results show that our compensation scheme can address the loss of thrust due to the overlap between the main body and the propellers, guaranteeing higher tracking accuracy, without requiring complex and computationally expensive aerodynamical models. To the best of our knowledge, this is the first work counteracting the aerodynamic effects of a morphing quadrotor during flight and showing the effects of partial overlap between a propeller and the central body of the drone.

Motion Control of a Hybrid Quadruped-Quadrotor Robot

“…The individual thrust f i provided by a single rotor without morphing is given by Equation ( 13), where the thrust coefficient called c t is a positive constant. Considering the presence of a morphing case under the actuated thigh servo motors, we reformulate Equation ( 13) as [28]:…”

Design and Control of a Midair-Reconfigurable Quadcopter Using Unactuated Hinges

“…In [3], a vehicle that uses several servomotors to actuate a scissorlike structure that can shrink or expand the size of the vehicle is presented, and in [4], a single servomotor is used in conjunction with an origami structure to enable the arms of a quadcopter to shorten or lengthen during flight. Vehicles that use a central actuator to change the angle of their arms in an X-shape are presented in [5] and [6], and a vehicle that uses four servomotors to change each arm angle is presented in [7] and extended in [8]. In [9] and [10], a quadcopter design is presented that is capable of using one or more actuators to reposition the propellers of the vehicle to be above one another such that the horizontal dimension of the vehicle is reduced.…”

“…is linear with respect to dE CE , ωB BE , and propeller thrust f p i . Recall that f p i can be computed by inverting the mapping given in(8), meaning that dE CE , ωB BE , and f p i are all linear functions of f Σ and τ B . Thus, we find that the torque about hinge i is also a linear function of f Σ and τ B .…”

Nonlinear Robust Control of a New Reconfigurable Unmanned Aerial Vehicle

“…The same controller has been used to control and stabilize reconfigurable quadrotors with exendable arms in the series of references [15][16][17]. To optimize the consumed energy and in order to choice the appropriate configuration for each flight phase, a LQR has been applied to control a reconfigurable UAV for different flight scenarios [18,19]. A conventional PID controller has been exploited by Riviere et al [20], in order to stabilize a quadrotor with variable mechanical structure.…”