Research Article An Electromechanical Pendulum Robot Arm in Action: Dynamics and Control A. Notué Kadjie, P. R. Nwagoum Tuwa, and Paul Woafo Laboratory of Modelling and Simulation in Engineering, Biomimetics and Prototypes, Department of Physics, Faculty of Science, University of Yaound´ e I, P.O. Box 812, Yaound´ e, Cameroon Correspondence should be addressed to Paul Woafo; pwoafo1@yahoo.fr Received 22 June 2017; Revised 18 October 2017; Accepted 8 November 2017; Published 5 December 2017 Academic Editor: Francesco Pellicano Copyright © 2017 A. Notu´ e Kadjie et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te authors numerically investigate the dynamics and control of an electromechanical robot arm consisting of a pendulum coupled to an electrical circuit via an electromagnetic mechanism. Te analysis of the dynamical behavior of the electromechanical device powered by a sinusoidal power source is carried out when the efects of the loads on the arm are neglected. It is found that the device exhibits period-n T oscillations and high amplitude oscillations when the electric current is at its smallest value. Te specifc case which considers the efects of the impulsive contact force caused by an external load mass pushed by the arm is also studied. It is found that the amplitude of the impulse force generates several behaviors such as jump of amplitude and distortions of the mechanical vibration and electrical signal. For more efcient functioning of the device, both piezoelectric and adaptive backstepping controls are applied on the system. It is found that the control strategies are able to mitigate the signal distortion and restore the dynamical behavior to its normal state or reduce the efects of perturbations such as a short time variation of one component or when the robot system is subject to noises. 1. Introduction Pendulum motion-driven systems have been intensively studied recently by both industries and research institutes because of their applications in diferent felds [1–10]. Some of these studies concern the analysis of the dynamical states and the development of control strategies to stabilize the dynamical state to a prescribed state. Tese pendulum models comprise the downward pendulum [5], horizontal pendulum [6], inverted pendulum [7], spherical pendulum [8], the fexible pendulum [9, 10], the pendulum excited by an RLC circuit based on nonlinear shaker [11], and rotating pendulum [12]. When the pendulum is coupled to an electrical part (electromechanical pendulum), its applications with and without control are more interesting in robotics and other felds of engineering. Tis is due to some particular dynamical states (periodic, quasiperiodic, and chaotic states) that the electromechanical pendulum can generate because of intrinsic angular nonlinearity or due to natural or imposed nonlinearities in the electrical part [5, 9–12]. Te working state of a system with particular dynamics can be modifed because of the interaction with its envi- ronment or the application of some constraints or control laws. In this line, recent years have seen the development of various control strategies applied on electrical, mechan- ical, electromechanical, and even biological systems: some examples are the adaptive control [13], active control [14], the classical and active-backstepping controls [15, 16], and the sliding mode control [17]. An interesting contribution dealing with chaos control of a double pendulum arm powered through an RLC circuit is reported in [11] where the authors used the state-dependent Riccati equation control and the nonlinear saturation control techniques to suppress chaos in the dynamics of the double pendulum arm. Due to its impor- tance for engineering and robotic applications, the control of pendulum motion has been intensively studied using various approaches, including passivity-based control [18], nonlinear control [19, 20], sliding mode control [21], motion control of two pendulums [22], and bifurcation control [23]. In this work, the dynamics and the control of an elec- tromechanical pendulum with rigid and constant length Hindawi Shock and Vibration Volume 2017, Article ID 3979384, 13 pages https://doi.org/10.1155/2017/3979384