Abstract
We have been investigating how to use microorganisms for bio-micromachines. We succeeded to rotate φ0.5mm micro impeller by motion controlled Paramecium. The Paramecium was controlled by the weak electrical field by applying their negative galvanotaxis. In our previous paper, we succeeded controlling paramecium very stably for over 100 laps along the star-shaped target route in the vertical plane. The overrun on the downward route, however, was larger than that on the upward route in the vertical plane. It was caused by the difference of the swimming speed on each of routes. In this paper, we developed a new motion control algorithm to decrease this overrun. In our former algorithm, the change timing of the target point was decided by the previous change timing and the previous turning point. In the new algorithm, we change this adjusting method to refer the same target point of the past laps using smoothing value calculated by the integral of the equal ratio attenuation. By using this adjustment method, we succeeded to decrease the overrun. We also investigated the transportability of the object by using motion controlled paramecium in the vertical pool. We found that paramecia often cause their avoiding reaction when they hit object made of hard material. In the case of the object made of soft material, paramecia can push more often and more easily. Therefore, we decided to change the target object from hard plastic to soft gel. We succeeded to transport and drop a gel oval sphere to the target place by manually controlled paramecium in the vertical plane pool.
