In this paper, a novel aerial manipulation paradigm, namely an aerial continuum manipulation system (ACMS) is introduced. The proposed system is distinct from the conventional aerial manipulation systems (AMSs) in the sense that instead of conventional rigid-link arms a continuum robotic arm is used. Such an integration will enable the benefits of continuum arms especially in cluttered and less structured environments. Despite promising advantages, modeling and control of ACMS involve several challenges. The paper presents decoupled dynamic modeling of ACMS arm using the modified Cosserat rod theory. To deal with the problem of complexity and high level of modeling uncertainties, a robust adaptive control approach is proposed for the position control of ACMS and its stability is proven using Lyapunov stability theorem. Finally, the effectiveness of the proposed scheme is validated in a simulated environment.

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Quadcopters, hexa-copters and multi-rotor unmanned aerial vehicles (UAV) in general have become one of the most common types of vertical takeoff and landing (VTOL) aerial vehicles where the thrust vectors of all the rotors are usually parallel. These UAVs are typically under-actuated meaning that the number of actuators is less than the degrees of freedom of the vehicle and because of that they cannot achieve holonomic motion. Recently, new designs for multi-rotor UAVs are proposed where the thrust vectors of the rotors are not necessarily parallel, and the rotors can have specific orientations with respect to the body of the vehicle. These new designs can achieve holonomy by manipulating thrust forces and moments of individual rotors which results in independent control of attitude and position of the UAV. In this paper, modeling of forces and moments of rotors is presented first. Second, translation and rotation model of the vehicle is presented, followed by nonlinear optimal control design for attitude and position of the vehicle. Attitude controller is designed according to the state dependent Riccati equation (SDRE) in nonlinear optimal control. Using input-state feedback linearization technique, we simplify the problem and then an analytical solution-utilizing quaternion parametersfor the SDRE is presented. Similarly, a linear quadratic regulator (LQR) for controlling the speed and position of the vehicle is designed. In addition, using Lyapunov theory, proofs for global asymptotic stability of all controllers are provided. Finally, simulations verifying the results are presented.

Aerial continuum manipulation systems (ACMSs) were newly introduced by integrating a continuum robot (CR) into an aerial vehicle to address a few issues of conventional aerial manipulation systems such as safety, dexterity, flexibility and compatibility with objects. Despite the earlier work on decoupled dynamic modeling of ACMSs, their coupled dynamic modeling still remains intact. Nonlinearity and complexity of CR modeling make it difficult to design a coupled ACMS model suitable for practical applications. This paper presents a coupled dynamic modeling for ACMSs based on the Euler–Lagrange formulation to deal with CR and the aerial vehicle as a unified system. For this purpose, a general vertical take-off and landing vehicle equipped with a tendon-driven continuum arm is considered to increase the dexterity and compliance of interactions with the environment. The presented model is independent of the motor’s configuration and tilt angles and can be applied to model any under/fully actuated ACMS. The modeling approach is complemented with a Lyapunov-wise stable adaptive sliding mode control technique to demonstrate the validity of the proposed method for such a complex system. Simulation results in free flight motion scenarios are reported to verify the effectiveness of the proposed modeling and control techniques.

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