Excellent control of flexible systems via control of the actuator-system interface

Many control strategies have been proposed for the common situation of an actuator attempting to control the end-point of a flexible mechanical system. It is here proposed that the best approach is to focus not on controlling the end point, nor on modeling/measuring the flexible system, but on the actuator-system interface, first to understand it, then to measure the two-way motion there, and finally to manage this motion. This leads to superb control. It is rapid, robust, energy efficient, unusually generic, and computationally light. It needs only modest sensing, only generic knowledge of the flexible system dynamics, and makes modest demands on the actuator dynamics. It can easily get the entire system to stop dead exactly at target, with slight vibration in transit.