Affiliation: | (1) Department of Cybernetics, University of Reading, PO Box 225, RG6 6AY Whiteknights, Reading, UK;(2) Department of Mechanical and Electrical Engineering, Aston University, Aston Triangle, B4 7ET Birmingham, UK;(3) Center for Engineering Research Technikon Natal, PO Box 953, 4000 Durban, South Africa |