A Time Domain Method for Estimating Forces Applied to an Unrestrained Structure

Abstract

A new method for the estimation of forces applied to a structure is presented. This time domain technique uses the structures response time history and returns an estimate of the applied force time history. This technique allows near-real-time estimation of input forces for non-collocated sensor/actuator pairs for multi-input/multi-output systems. Two examples are presented. The first is a single-input/single-output one-dimensional spring/mass chain in which a remote accelerometer is used to estimate an input force at one end. In the second example, the technique is used to estimate six docking forces and moments between the Space Shuttle and the Russian MIR Space Station during a numerical simulation of a docking event.