Current Research

Machining Accuracy Improvement Through Visual Control of an Active Display

Principal investigators:

Laine Mears and John Ziegert

Graduate students:

Chan Wong and Carlos Montes

Sponsor:

National Science Foundation

Brief abstract:

The goal of this proposal is to investigate a new class of spatial position measurement systems where the sensing element observes an active target whose properties are dynamically controlled by the user. It is anticipated that digital sensing of a controllable array of pixel elements will allow high-precision position and orientation information to be communicated for the purpose of motion control of simultaneous-axis positioning. Therefore, the objective of this research is to determine if the achievable resolution of such an active image sensing system can be completely defined by the fundamental size of the array element, the true element shape, viewable array size, system magnification and color depth controllable by the user. The approach is to first formulate a physics-based relationship between achievable resolution and the system parameters of interest, and to predict the system resolution over an applicable range of test cases. Experiments will then be performed to observe actual achievable resolution and verify the prediction. After resolution is verified, the system will be tested on a two-axis positioning stage for simultaneous axis closed-loop motion control.

Successful results of this research will enable design of a true closed-loop motion control system for simultaneous axis positioning of multi-degree-of-freedom manufacturing equipment. Such a design has the potential to eliminate the need for complex and expensive axis error mapping, significantly reducing cost and greatly increasing usability and applicability in a number of manufacturing applications.

Impact:

Broader impacts of the research include: fundamental advancements in accuracy and direct control of manufacturing equipment using vision detection of an actively controlled display; intelligent pattern generation for ultrafine position control; analysis and reduction of uncertainty in digital image generation and sensing; optimal architecture of a new class of position sensing; and control of coupled systems with disparate update rates. The proposed embodiment is low cost and has wide applicability for manufacturing equipment positioning over a range of scales for any system requiring multidimensional precision feedback. Results of this work will be disseminated to the engineering community through journal and conference publications.  Additionally, an interactive Web site will be established to track the current state of work and to provide online simulation demonstrations of the fundamental ideas.

Project schedule:

July 2008 to June 2011
Clemson University