Abstract
This paper presents an direct design scheme of model reference adaptive control (MRAC) for pneumatic servo system with additive external forces. In this design scheme, the controller contains the mechanism which can eliminate the constant disturbances caused by additive external forces. As the result, the proposed design scheme works well in the presence of the constant disturbances. The effectiveness of the proposed design scheme of MRAC has been confirmed by experiments carried out using the existent pneumatic servo system.