Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form

A Practical Method for Friction Compensation in Rapid Point-to-Point Motion

Bucci, Brian Arthur (2011) A Practical Method for Friction Compensation in Rapid Point-to-Point Motion. Doctoral Dissertation, University of Pittsburgh. (Unpublished)

Primary Text

Download (1MB) | Preview


Rapid point-to-point motion of a servo mechanism has obvious industrial applications. Due to their low cost, simplicity, application flexibility, and position stability, rolling element bearings are often a good choice for servos used in such processes. As industrial processes begin to require nanometer tolerances, settling time of a servo after a step motion has significant impact on process throughput. For most servo problems, linear systems theory works well to describe and predict servo response. However, on the sub-micrometer length scale, friction causes the servo to become a highly nonlinear system. Thus, a linear representation of the system that works well to describe and predict system performance on a larger length scale, does not work for sub-micrometer displacements. This leads to servo settling times that are much longer than would be predicted by linear systems theory. While methods of friction compensation, such as feedforward and friction observers, have been investigated in other efforts, they may not be entirely appropriate for the point-to-point motion problem. Further, the apparent frictional parameters of the servo mechanism appear to change in a way that is not easily quantifiable. Analysis of previous methods of friction compensation is often based on the assumption of perfect model matching and the unavoidable error between the actual friction process and the modeled friction process can have large negative impact on the efficacy of these previous methods. Thus, this work aims to design a friction compensation method that realistically considers uncertainty in the friction process and performs robustly with one simple parameterization of the algorithm.


Social Networking:
Share |


Item Type: University of Pittsburgh ETD
Status: Unpublished
CreatorsEmailPitt UsernameORCID
Bucci, Brian
ETD Committee:
TitleMemberEmail AddressPitt UsernameORCID
Committee ChairVipperman, Jeffreyjsv@pitt.eduJSV
Committee MemberCole, Danieldgcole@pitt.eduDGCOLE
Committee MemberLudwick,
Committee MemberClark, Williamwclark@pitt.eduWCLARK
Committee MemberMao, Zhi-Hongshm4@pitt.eduSHM4
Date: 27 June 2011
Date Type: Completion
Defense Date: 13 January 2011
Approval Date: 27 June 2011
Submission Date: 27 March 2011
Access Restriction: No restriction; Release the ETD for access worldwide immediately.
Institution: University of Pittsburgh
Schools and Programs: Swanson School of Engineering > Mechanical Engineering
Degree: PhD - Doctor of Philosophy
Thesis Type: Doctoral Dissertation
Refereed: Yes
Uncontrolled Keywords: bearings; friction; friction control; nonlinear control; point-to-point motion
Other ID:, etd-03272011-152630
Date Deposited: 10 Nov 2011 19:33
Last Modified: 15 Nov 2016 13:37


Monthly Views for the past 3 years

Plum Analytics

Actions (login required)

View Item View Item