A Stewart platform manipulator (SPM) is employed for multi-axis vibration control of a slender structure, using the concept of flow source-based vibration control. In order not to reach motion limit of the manipulator system, a hybrid dynamics associated with the flexible and desired SPM error dynamics is also proposed as the control object. It is experimentally shown that the flexible vibration and the base motion of the test structure can be effectively controlled by the SPM. (C) 2001 Elsevier Science Ltd. All rights reserved.