In this paper, a recently proposed assistive controller, called output feedback assistive control method (OFAC), is applied to a single axis stage. The OFAC method employs inherent properties of series elastic actuators (SEAs) to provide assistance to compliantly actuated systems without requiring any information about contact forces, systems accelerations or their future paths. Therefore, there is no need to extra controversial sensors, e.g. load cells and accelerometers, and a more reliable control system with lower costs is obtained. Modifying the system modeling to include dry friction effect, the practical performance of the OFAC method is further evaluated in this study. The OFAC method is implemented on a single axis stage which is designed to have a linear SEA as a supplementary force source. The experimental results clearly indicate the effective performance of the OFAC method in practical conditions.

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