Angular control of differential shape-memory alloy spring actuator for underactuated dynamic system

Abstract

This article dwells on two technical aspects, the design and implementation of an upgraded version of the differential shape-memory alloy–based revolute actuator/rotary actuating mechanism for stabilization and position control of a two-degree-of-freedom centrally hinged ball on beam system. The actuator is configured with differential and inclined placement of shape-memory alloy springs to provide bidirectional angular shift. The shape-memory alloy spring actuator occupies a smaller space and provides more extensive reformation with justifiable actuation force than an equally able shape-memory alloy wire. The cross or diagonal architecture of shape-memory alloy springs provides force amplification and reduces the actuator’s control effort. The shape-memory alloy spring–embodied actuator’s function is exemplified by the highly dynamic underactuated custom-designed ball balancing system. The ball position control is experimentally demonstrated by cascade control using the control laws that have been unattempted for shape-memory alloy actuated systems; the ball is positioned with linear (integer-order and fractional-order) proportional–integral–derivative controllers optimized with genetic algorithm and particle swarm optimization at the outer/primary loop. Angular control of the shape-memory alloy actuated beam is obtained with nonlinear (integer-order and fractional-order sliding mode control) control algorithms in the inner/secondary loop.

Robust Approach for Global Stabilization of a Class of Underactuated Mechanical Systems in Presence of Uncertainties

“…Te proof is simple. Taking V � (1/2)σ 2 1 as Lyapunov for ( 16), and then using (17), the derivative _…”

“…Tese strategies are also suitable for the class of UMSs that are approximate inputoutput linearizable, for example, the Cart-Pole and the Balland-Beam system, but they cannot be applied to the whole class of UMSs. A systematically unique design strategy is usually used for such systems such as IWP [13], TORA [14], the Furuta Pendulum [15], the Overhead Crane [16], and the Beam-and-Ball [17] due to complex dynamics. In literature, a design framework is also proposed which enclose systems in a specifc class, e.g., controlled Lagrangian [18], equivalent-input disturbance [19], sliding mode [20], energy-based [21], IDA-PBC [22], output feedback stabilization [18], dynamic surface control [23], and adaptive approaches [14].…”

Trajectory tracking control of parallel manipulator actuated with shape memory wire

“…The development of a 3-DOF parallel manipulator with an SMA spring was proposed by Pishbin et al (2017) and Ranjith et al (2018). The one-dimensional model of a ball and plate called ball and beam was developed using SMA wire by Sunjai et al (2015) and SMA spring by Banu Sundareswari et al (2020, 2022). The proposed work is designed to depict the viability of shape memory alloy wire actuators for actuating multiple revolute joint structures, such as a parallel manipulator that is implemented for dynamic ball balancing applications.…”