Improved Process Control in Camshaft Grinding Through Utilization of Post Process Inspection With Feedback

Abstract:

In order to take full advantage of the introduction of computer numerical control technology in camshaft grinding and post-process inspection, a closed loop control scheme is proposed. This strategy makes use of post-process inspection results to modify the commanded part geometry used in the grinding program. The commands are modified in order to minimize the lobe contour and relative timing errors. It is shown that using a control strategy comprised of feedforward and feedback elements, substantial improvements in cam contour accuracy can be attained. A system capable of automated reduction of inspection results, application of statistical methods, transformations between different coordinate systems, and production of modified commanded part geometry is presented. This system requires no off-l;ine calibration or learning of grinding machin positioning errors. Additionally, it offers advantages over such techniques, in that it is able to automatically adapt to changing process conditions. the sytem is general in nature and may be used for any camshaft design. Through application of this system, the time required to bring a new part into tolerance is greatly reduced. With such a system used to minimize contour errors, it is no longer necessary to optimize grinding parameters based on these errors. Rather, grinding parameters can be manipulated to optimize other important factors, such as metal removal rates and the corresponding process time. Implementation of this system on existing computer numerically controlled (CNC) equipment is inexpensive. It requires only software necessary to produce the modified part geometry and limited hardware for file transfer. The required hardware is inexpensive and readily available.

Dissertation Discovery Company and University of Florida are dedicated to making scholarly works more discoverable and accessible throughout the world. This dissertation, "Improved Process Control in Camshaft Grinding Through Utilization of Post Process Inspection With Feedback" by timothy mark Dalrymple, was obtained from University of Florida and is being sold with permission from the author. A digital copy of this work may also be found in the university's institutional repository, IR@UF. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation.