Abstract
In this paper, we investigated to drive a seesaw by position controlled downward flow of the Euglena's bioconvection. The position of the downward flow was controlled by applying Euglena's phototaxis to the scanning blue laser beam. Formally, we succeeded to drive a seesaw by electrically position controlled downward flow of the Tetrahymena's bioconvection. In this paper, we aimed to reproduce the laser control version of this seesaw driving by using Euglena. We have already confirmed that if the experiment is done in the horizontal planar pool, we could make any shapes of Euglena group and we could also assemble simple mechanical parts by pushing the part by Euglena group. In this study, we first investigated the basic conditions to control the bioconvective downward flow by irradiating the scanning blue laser. The results, however, showed that to generate and to control a steady bioconvective downward flow was very difficult due to the Euglena's poor swimming performance. We reduced the friction of the seesaw and introduce the arc shaped scanning to guide the Euglena located at around the pool side into the bioconvective flow. By using this scheme, we could drive the seesaw up to one reciprocating motion.
