Page 256 - Robots Androids and Animatrons : 12 Incredible Projects You Can Build

11.3 Tripod gait, second move,
shifting weight

235
11.4 Tripod gait, third move

We will build a walker robot that imitates a tripod gait. The walker
outlined in this chapter requires a minimum of three servo motors.
There are numerous hexapod and quadrapod walker designs that
require greater freedom of movement per leg. Greater freedom of
movement per leg means more independent drivers per leg. If one
is using servo motor drivers, this can be achieved using two, three,
or four servo motors per leg.
The need for so many servo motors (drivers) is because each leg
on the walker needs to have a minimum of two axes (degrees) of
freedom. One to move up or down and the second to move (swing)
forward and back.

Three-servo walker
The walker robot we will make is a compromise in design and con-
struction, but requires only three servo motors. Even so, using just
three servo motors, it is a true tripod gait walker. Our walker uses
three lightweight HS300 servo motors [42-ounce (oz) torque] and
a 16F84-04 microcontroller.

Team LRN Walker robots