Abstract: In this paper,an approach that directly registers the exciting force produced by a moment actuator is described.A model of the dynamic performance of the magnetostrictive rod moment actuator is also proposed.Factors that influence t c1532.ctx the output moment of the actuator are discussed and a theoretical basis is established so that the mechanical design can beimproved.The purity and frequency characteristics of output moment of a prototype have been measured and results are in agreement with theoretical analysis.The reciprocal relationship is assessed,and causes of measurement errors are discussed.