Anticipatory Postural Adjustments for Balance Control of Ball and Beam System

Abstract

Designing a robust controller for nonlinear unstable system involves major constraints such as nonlinearity, disturbance and uncertainity. Therefore, a control strategy realization for such unstable systems generally explores interests among scientific community. The objective of the present study was to design a control strategy of anticipatory postural adjustments for balancing of ball and beam system. Due to the characteristics like unstable, nonlinear and double-integrating, the ball and beam system is commonly considered as a benchmark control operation for estimating several control strategies. Although a PID, i.e. proportional–integral–derivative controller, can be developed for stable system, for double-integrating unstable system, it is very less common. In order to control the ball’s position, a PID controller as non-model-based control strategy was presented in this study. To obtain the dynamics of ball and beam system, Euler–Lagrangian approach is used. The system’s prototype was built using UV sensor as feedback network; servomotor as an actuator; and Arduino microcontroller as PID controller. Simulation models such as set-point tracking and disturbance rejection analysis of ball and beam system are performed using MATLAB/Simulink in order to evaluate the performance of proposed system. The outcomes revealed that the proposed system provides increased stability and reduced percentage of error. Along with these, transient response is also improved and the system is more robust against disturbance.