Wall Hugging Mouse Works
The Wall Hugging Mouse consists of two battery-operated motors, each of
which is connected to its own wheel. Pressing and releasing a wire "whisker"
on the Mouse's left side controls a switch (see diagrams on the next page).
When the whisker is released, as in the diagram on the top, a circuit is
completed with Motor A. Motor A turns on and causes Wheel A to turn. Wheel B
remains stationary, so the Mouse turns in a circle to the left. When the
whisker is pressed, as in the diagram on the bottom, the switch attached to it
breaks the circuit with Motor A and completes a circuit with Motor B, causing
Wheel B to turn. This causes the Mouse to turn to the right. Because of the
way the whisker switch works, only one motor can be on at a time. When one
motor is on, it causes the attached wheel to turn. When one wheel is turning
and the other is not, the Mouse turns in the direction that is the opposite of
the wheel that is turning. In other words, when only the right-hand wheel
turns, the Mouse circles to the left. When only the left-hand wheel turns, the
Mouse circles to the right.
If you place the Mouse in an open area where there is nothing to press
against its whisker, it will simply turn in a circle to the left. If you tape
the whisker to the Mouse’s body, the whisker will stay pressed and the Mouse
will turn in a circle to the right. In short, a pressed whisker produces a
right turn; a released whisker produces a left turn. If you position the Mouse
so that there is a wall (or other surface) on its left that will press against
the whisker, the Mouse will follow along the wall with a jiggling motion.
The Mouse "jiggles" because it starts out with the whisker released and
so turns left toward the wall (with Motor A on, B off) until the whisker
reaches the wall. When the wall presses against the whisker, the motors switch
(A off, B on) and the Mouse starts to turn right, away from the wall. As soon
as it has turned far enough that the whisker is released again, the motors
switch again (B off, A on), producing a left turn. The Mouse now turns back to
the wall, causing the whisker to be pressed again. As it repeats this process
over and over, the Mouse jiggles its way along the wall on its left.