A six-degrees of freedom fine motion mechanism

Abstract The purpose of the study is to accomplish the six-degrees of freedom (dof) fine motion mechanism which has the characteristics that each of the six one-dof motions has the same control characteristics, that the number of actuators is the same and least for each one-dof motion and that each one-dof motion does not interfere in the others. First, the paper discusses a design method for the mechanism. Then an experimental mechanism is introduced to justify the design method. Open loop transient characteristics of the six one-dof motions of the mechanism are same, though the interferences are observed between the motions. Finally, the six one-dof motions of the mechanism are controlled with the controllers designed taking only one of the six one-dof motions into account. The same control characteristics of the five one-dof motions as those used for the controller design are realized. Namely, it is shown that a controller for each motion does not need to be designed individually. Both of the state and dynamic interferences were eliminated with the control.