S Cam and Shoe Roller Contact Point: An Iteration Procedure

The determination of the points of contact between an S cam and brake shoe rollers cannot be determined explicitly by mathematical methods. An iteration procedure is developed which allows the points of contact to be determined for any cam rotation. A mathematical proof is given which verifies the iteration procedure for one of the two cases examined. Examples for a brake are worked out which show how the iteration procedure converges on the actual contact points.