1. Integrated Manufacturing Technologies Institute, National Research Council Canada, 800 Collip Circle, London. Ontario N6G 4X8, Canada
2. Department of Mechanical and Manufacturing Engineering, University of Calgary, 2500 University Drive, N. W., Calgary, Alberta T2N 1N4, Canada
3. Integrated Manufacturing Technologies Institute, Western Laboratory, National Research Council Canada, 3250 East Mall, Vancouver, B. C. V6T 1 W5, Canada