A boundary gradient search technique and its applications in design centering

A boundary gradient search technique is introduced. The technique generates a sequence of points on the boundary of the feasible region converging to a fixed point. The gradient of the boundary at this fixed point has a prespecified directional ratio. The boundary search technique is exploited in a modification of the ellipsoidal technique for design centering. This modification allows the use of double-sided ellipsoidal sections instead of single-sided ellipsoidal sections. It improves the speed of convergence of the ellipsoidal technique. Also, a computationally inexpensive technique of determining the gradient of the gain constraints is introduced. Practical examples are given to demonstrate the new technique.