Computation of common normals between wheel and rail surfaces

Computation of contact points between the wheel and rail is a fundamental problem in dynamic simulation of trains. To compute these contact points, one needs to locate the common normals. The objective of this study is to develop an efficient method to compute common normals between a pair of wheel and rail surfaces. To achieve this objective, two basic problems are addressed. The first is to devise a procedure to estimate all common normals. The second problem is to use the estimates found as the initial guess in an iterative scheme to accurately compute the location of common normals. The efficacy of the proposed approach is also evaluated.