The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 08, 2021
Filed:
Sep. 27, 2018
Fisher Controls International Llc, Marshalltown, IA (US);
Christopher S. Metschke, Ames, IA (US);
Michael R. Fontaine, Marshalltown, IA (US);
Kenneth W. Junk, Marshalltown, IA (US);
David L. Smid, Marshalltown, IA (US);
FISHER CONTROLS INTERNATIONAL LLC, Marshalltown, IA (US);
Abstract
A control loop for a double-acting pneumatic actuator is configured to generate two control signals, one for each of the two pneumatic chambers for the purpose of controlling the actuator position in view of operating constraints on the chamber pressures or the stiffness of the actuator. A numerical indicator of the stiffness may be computed in a variety of ways, for example, as the average of the two chamber pressures. In one embodiment a numerical indicator of stiffness is treated as an output of the system along with the position of the actuator. A multi-input multi-output control loop with position and pressure feedback may be used to simultaneously control the position and the stiffness of the actuator.