Model Fish Robot, PPF-06i

Model Fish Robot, PPF-06i

September 11, 2000 by Koichi Hirata

Model Fish Robot, PPF-06i

The model fish robot named PPF-06i is controled by a micro-computer. As the first step of the development of autonomous robots, the PPF-06i has been developed.

Basic Structure of the PPF-06i

The purposes of the PPF-06i are, (i) Swimming of the fish robot using R/C servomotors controled by a micro-computer, (ii) Simple control by sensors. In order to change the program on the micro-computer easily, the micro-computer is located above side of the fish robot. Thus, the fishlike propulsive device (tail fin) is located below side of the hull.
Two serbomotors move a tail peduncle and a tail fin respectively. The servomotors, a battery and touch sensors (micro switch) are located in the wood hull. Any waterproofed seal is not needed, because the servomotors are connected to the tail peduncle and fin over the hull. The tail peduncle and fin are made by hard wood.

Touch Sensor

Touch sensors are set on the hull. When the sensors are felt any force, their signals are sent to the micro-computer. The fish robot can avoid the obstacles by the suitable program, though the program has not prepared yet.
Also, I confirmed the function of the touch sensors with the swimminf fish robot, but the sensors did not work well. The installation and structure of the sensors are needed to reform and reconsider.

Conclusion

It was confirmed that the PPF-06i swims with swimming speed of about 0.1 m/s using the micro-computer. Also, it was confirmed that the PPF-06i turns with turning diameter of about 1 m, when the tail swings to one side during the turning. I think that one of the above purposes, (i) Swimming of the fish robot using R/C servomotors controled by a micro-computer, was achieved approximately.
On the other side, another of the purposes, (ii) Simple control by sensors, has not been achieved. I gave up the control of the PPF-06i. Because, the PPF-06i does not have good dynamics performance, so I thought that the development of the new fish robot is better.

Let's build the Fish Robot! (Wood Hull Processing)
Movie of PPF-06i (MPEG, 1.2 MB)

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