Page 42 - LEGO MINDSTORMS - Robotics Invention System-2 Projects

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Robot 2 • Funky Chicken Techno-Walker

Most common forms of transportation rely on wheels to move. However, most
living beings do not have wheels; we use legs! Naturally, as we design robots to
be some limited imitations of ourselves, we would like some of them to be able
to “walk.” Walking has many advantages over wheels: A walker can adjust to
many different terrains, climb up stairs, and climb down stairs, just to name a
few. But even the most advanced robotic walker in the world can only barely
accomplish these feats that we as humans perform every day without thinking.
This is a simple robot that mimics the basic patterns of walking. This
model is a walker, but not a complex one. It cannot walk up stairs, handle ter-
rains, or even turn. Robots that can do those things require a tremendous
number of motors, joints, and complex programs to control it. It has two legs,
each of which make the correct walking motions. In order to achieve the correct
timing for both the legs, the two legs are rotationally offset and joined by one
axle. This allows one motor to drive two legs creating two motions! This model
relies on completely mechanical solutions to solve the walking problem. But it
can walk forward and does so with a minimum of parts and requirements.
There is no programming needed to get this model to walk correctly.
Since we are using only one motor to drive the entire model, the model
cannot be too heavy. The heaviest elements of any robot in real life or LEGO
are usually the batteries. We can solve this problem easily here by not attaching
the RCX to the body of the model. When you are finished with the model,
simply connect the wires from the motors to the RCX brick to make the model
walk. Be sure to use long connecting wires from the motors to the RCX brick.
Short wires will work but long wires will allow your walker to walk more
freely.

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