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:
Feb. 21, 2012
Filed:
Jul. 05, 2007
Yuhong Zheng, Ann Arbor, MI (US);
Yuhong Zheng, Ann Arbor, MI (US);
Kelsey-Hayes Company, Livonia, MI (US);
Abstract
A method for adapting a closing boundary for a proportional spool valve includes generating or detecting a pressure command signal. Next a pressure error is obtained by subtracting an actual wheel brake pressure from its pressure command. Then a modified pressure error is calculated a modified pressure error is calculated in such a way that steady state pressure errors resulting from mismatched feedforward term, control deadzone and other factors are subtracted from measured pressure error to leave the only error to be that due to boundary deviation. An estimator is then used to estimate an apply boundary deviation or a release boundary deviation of the spool valve, as appropriate. A boundary table is updated using the resultant boundary deviation estimate.