SUMMARY We propose an inchworm‐type microactuator which uses levitation caused by vertical vibration. The vertical vibration is generated by a piezoelectric actuator. The inchworm usually consists of thrust elements and clamp elements. The proposed inchworm‐type microactuator however does not use any clamp elements. Three levitation elements are connected with two thrust elements which are stacked piezoelectric actuators. The levitation element consists of a mass, a piezoelectric actuator, and a plate. The vertical vibration of the piezoelectric actuator lifts the levitation elements and eliminates the friction. By controlling the phase of the horizontal and vertical piezoelectric actuators, the inchworm moves in a linear direction. The levitation height and the position of the inchworm are measured, and experimental results show the feasibility of the proposed inchworm. The mechanism described in this paper is effective in a precise positioning system in a clean room.

No abstract

No abstract

This paper proposes a new intelligent control method for autonomous mobile robots to acquire appropriate actions based on a real-time action search. In the proposed method, information criterion on the virtual environment is defined based on Kullback-Leibler divergence, which measures quality of the environmental information used for the action search. The robot searches suitable actions based on the environmental information whose quality is improved step by step. By applying the proposed method, the trade-off between calculation amount and information quality is taken into account, and the search process converges faster. The proposed method is applied to the moving obstacles avoidance problem, and its usefulness is verified through some simulation results.

No abstract