Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
SLIDING MODE CONTROLLER OF A COMPACT HYDRAULIC SERVOVALVE DEVELOPED FOR AN IN-PIPE CLEARANCE ROBOT
Submission Author:
Gabriel Squizani Manske , RS
Co-Authors:
Gabriel Squizani Manske, Eduardo André Perondi, Celso Luís Teixeira, Henrique Mendel, Hugo Francisco Lisboa Santos
Presenter: Gabriel Squizani Manske
doi://10.26678/ABCM.COBEM2021.COB2021-0309
Abstract
Obstruction of underwater oil pipes is a recurrent problem that results in time and economic losses for companies in the offshore petroleum extraction field. The Annelida robot consists in a wall-pressing inchworm type robot designed for inspection and cleaning of underwater oil pipes, also called risers. The robot moves inside the risers driven by a hydraulically actuated locomotive, based in a double-action actuator, whose “legs” connect internally to the pipe walls by means of a self-locking mechanism. The main actuator of the locomotives is powered by a compact electro valve with a regenerative circuit, specially designed for current application. The valve is a spool type, operated by a nonlinear solenoid. In this paper, the mechanical dynamics of the spool valve and its solenoid behavior are modelled. Further, a feedback linearization strategy is applied to compensate the solenoid nonlinearity, and a sliding mode controller is designed and applied to control the valve spool trajectory. These strategies were combined to guarantee a robust control of a system with high nonlinearities. The dynamic model and the proposed controller are applied in simulations and the results compared with that of a standard PID controller. The simulations results show that the sliding mode with feedback linearization controller is able to effectively control the spool system, even in the presence of nonlinearities in the solenoid, and that its behavior, when comparing by means of transitory parameters, is similar to that of a PID controller. Also, an experimental setup was built using a prototype of the hydraulic valve specifically designed and manufactured for this application. Experiments were conducted with the valve disconnected from a hydraulic unit, operating it in its opening and closing motion in open loop, aiming to evaluate the proposed dynamic model of the valve. The data obtained show that the dynamic behavior of the valve prototype presents is similar to that of the mathematical model used in the simulations. With the model evaluated, the proposed control strategy is considered apt to be implemented and tested in the valve prototype.
Keywords
Feedback Control, Hydraulic Valve Control, Hydraulic Regenerative Circuit, Pipe Clearance Robotics, Digital Control
