ASPE Logo  




ASPE Meetings

 2010 Summer Topical Meeting
 25th ASPE Annual Meeting
 2011 Spring Topical Meeting

Quick Links

 Join ASPE Group on LinkedIn
 Precision Engineering Journal
 ASPE Proceedings
 Corporate Sponsorship
 Announcements

 

Precision Engineering is the Future of Manufacturing

Here is the first issue of our new quarterly newsletter which will remind you of important precision engineering principles and keep you informed of upcoming activities.

Our goal of the ASPE is to assist in your technical growth, to advance your career and to ultimately advance manufacturing in America.

We look forward to your comments and welcome your participation in upcoming ASPE events.

Tom Dow, Executive Director ASPE

 

Precision Tips

PATTERN #1: Repeatability*

Manufacturing advances are based upon increased levels of accuracy. To achieve acceptable accuracy, repeatability must be improved via minimizing a machine or instrument's response to stresses and influences.

Improving repeatability requires identifying and minimizing all known influences and stresses, for example thermal, seismic, friction, air turbulence, acoustic, varying mass loads, etc. First by measuring repeatability as these are systematically added back in, and second by improving repeatability via redesign or by applying environmental isolation until acceptable repeatability is achieved.

With repeatability established systematic errors are then reduced via three basic approaches to achieve accuracy:

 Reduction: Isolating the system by brute force or redesign to reduce sensitivity.
 Correction: Calibrate the system once and apply a correction routine with each action.
 Compensation: Measure and correct errors in real time through an appropriate model.

PATTERN #1: Design for repeatability; compensate and correct for system errors to achieve accuracy.

Next pattern: ISOLATION

*Based on "Patterns for Precision Instrument Design", a classic ASPE tutorial by C. Teague, C. Evans and later D. Swyt. It uniquely identifies 12 foundational mechanical concepts or patterns driving precision in fabrication, assembly and metrology.


The American Society for Precision Engineering promotes the future of manufacturing in America by advancing precision engineering; though supporting education; and encouraging the development and application of precision principles.

ASPE, founded in 1986, is a non-profit organization.

Click here to learn more about ASPE.