Our previous paper showed the adhesion state can be checked by analyzing the data obtained by laser displacement meter. However, the following problems happen. 1) The endeffector must be located at the specific point where laser displacement meter can measure oscillation. 2) The adhesion state can not be checked if something blocks the light/laser or the target leaves measuring point. 3) The total system becomes very large. Then, this paper firstly presents a method for checking the adhesion state by piezo-transducer. Next, to achieve more precision manipulation, we propose a method to move the endeffector with a more precision step. Adding DC input to the input for oscillating the endeffector for relaxing adhesion forces, we control the endeffector movement relaxing adhesion forces. Based on this method, we propose a method for checking the adhesion state more accurately and automatically. The first mode resonance frequency shifts with the increase of the amount of pushing the object by the endeffector. Using the amount of shift, we develop a method for checking the adhesion state.
