Page 296 - Amphibionics : Build Your Own Biologically Inspired Robot

Amphibionics 07 3/24/03 9:13 AM Page 275
Chapter 7 / Turtletron: Build Your Own Robotic Turtle
The robot exhibited four modes of operation described below.
1. Search. The room is at low light level or darkness. The robot
responds by searching for a light source. The steering motor
is on full speed and the drive motor is at half speed.
2. Move. The robot found light. The robot responds by turning
the steering motor off and the drive motor on at half speed.

3. Dazzle. The robot encounters bright light. The robot
responds by setting the steering motor to half speed, while
the drive motor is reversed.

4. Touch. The robot hits an obstacle. The robot responds by
setting the steering motor to full speed, with the drive motor
reversed.

In the 1950s, W. Grey Walter wrote two Scientific American articles
(“An Imitation of Life,” May 1950; “A Machine That Learns,”
August 1951) and a book titled The Living Brain (Norton, New York,
1963). Walter reported, “The strange richness provided by this
particular sort of permutation introduces right away one of the
aspects of animal behavior—and human psychology—that
Machina Speculatrix is designed to illustrate: the uncertainty, ran-
domness, free will or independence so strikingly absent in most
well designed machines.”
Although the robot we will be building is turtle-like, it is not
intended to recreate any of the experiments of W. Grey Walter,
although you could easily implement the sensors and program the
microcontroller to do so.

Mechanical Construction of Turtletron

The parts needed for the mechanical construction of the turtle
robot are listed in Table 7.1.

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