title: Robust force control in a novel electro-hydraulic structure using polytopic uncertainty representation.
abstract: Electro-hydraulic servo systems (EHSS) are used in many industrial applications for position and force control. Force control with a hydraulic actuator is challenging and requires complicated control algorithms used along with high crossover frequency electro-hydraulic valves, even for simple force control tasks. In this paper, a different hydraulic structure is proposed to improve the force tracking quality and increase efficiency in the EHSS. This comes at the cost of a new model with linearization and uncertainty challenges. To address these challenges, a robust H∞ control design approach is followed to control the proposed EHSS. Model linearization uncertainties are approximated by a polytope and a robust controller is designed to keep the system stable and satisfy the H∞ performance conditions within this polytope. Experimental results verify that the objectives of the paper are satisfied after using the proposed system.
authors.affiliation: Mechanical Engineering Department, Amirkabir University of Technology, Tehran, Iran. Electronic address: k_baghestan@aut.ac.ir.
authors.forename: K
authors.initials: K
authors.lastname: Baghestan
authors.affiliation: Mechanical Engineering Department, Amirkabir University of Technology, Tehran, Iran. Electronic address: smrezaei@aut.ac.ir.
authors.forename: S M
authors.initials: SM
authors.lastname: Rezaei
authors.affiliation: Electrical Engineering Department, Amirkabir University of Technology, Tehran, Iran. Electronic address: alit@aut.ac.ir.
authors.forename: H A
authors.initials: HA
authors.lastname: Talebi
authors.affiliation: New Technologies Research Center (NTRC), Amirkabir University of Technology, Tehran, Iran. Electronic address: mzare@aut.ac.ir.
authors.forename: M
authors.initials: M
authors.lastname: Zareinejad
keywords: Electro-hydraulic servo systems; Force control; Polytopic uncertainty