Mario's Lego Robotics Archive


This walker started when I decided to build a robotic version of a model found in the 8891 Idea book (pages 58-69). The central core of the robot actually IS that model, but then I decided to give the robot the possibility to change direction and avoid obstacles, and the result is an additional leg that features a motorized wheel mounted orthogonally to the direction of motion.
The behaviour this robot exhibits is very simple: it walks until one of the bumpers detects an obstacle, then it walks back one step, lower the third wheeled leg, activates the wheel to rotate itself, raise the leg again and resume walking. Warning, this technique doesn't work on thick carpets!

This robot attended a game called "interactions" during the Italian Legofest on Nov. 28 1999.

Left side view. The feet are interlaced, and a bit reinforced if compared to the original model, just to provided better support for the increased weight.
In this picture you can see the rotation sensor I used to detect the phase of the walking legs.

Rear view.

Rear right view. The touch sensor detects when the additional leg is in its up or down position.

Rear left view. Again the rotation sensor is visible, and the motorized wheel at the bottom of the additional leg.

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