Building Robots With Lego Mindstorms

Building Robots That Walk • Chapter 15 289

More complex leg geometries are also possible (see Figure 15.14). Designing

legs is almost an art—it requires good intuition, and a lot of patience to test and

improve your initial idea.

Building a Four-Legged Robot

Let’s start by building a robot with four legs in order to demonstrate the center of

gravity principle explained in Figures 15.5 to 15.7.The architecture is very simple,

and symmetrical: keep the COG as close as possible to the center (Figure 15.15).

We built it solely from RIS parts.

Removing the RCX, you’ll notice there’s a single motor which, through two

worm gears, provides motion to the front ...