Using two servovalves to improve pneumatic force control in industrial cylinders

• Type: Article in International Scientific Journal
• Date: 2013

Authors

João Falcão Carneiro (Author) FEUP; F. Gomes de Almeida (Author) FEUP

Journal

Title: International Journal of Advanced Manufacturing Technology

Vol. 66 No. 1-4

Pages: 283-301

ISSN: 0268-3768

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 13 Citations

ISI Web of Science

Scopus - 18 Citations

COMPENDEX

Scientific classification

FOS: Engineering and technology > Mechanical engineering

Other information

Authenticus ID: P-005-28X

DOI: 10.1007/s00170-012-4324-8

Abstract (EN): Pneumatic actuation systems present several advantages like low cost, high force/volume ratios, and the absence of significant heat or magnetic field generation. However, its use in complex control tasks is hindered by their highly nonlinear behavior. This drawback is caused not only by the nonlinear behavior of phenomena like friction but also by the large variation of some of the system proprieties with the system state. One of such proprieties is the fluidic stiffness of the actuator, which may suffer significant changes with the piston velocity when the pressure dynamics of both actuator chambers are coupled due to the use of only one servovalve. This dependency can be eliminated if the pressure (or pneumatic force) inside each chamber is independently controlled using two servovalves. In this paper, two pneumatic force allocation strategies are proposed and analyzed. In the first one, the stiffness of the actuator becomes independent of the pneumatic force reference. In the second one, the pneumatic forces are devised to avoid early pressure saturation of the cylinder chambers. Based on an experimental test rig, both strategies are compared against each other and against the use of only one servovalve.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 19