Instructions Circuit Diagram

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Detailed explanation
Starting from stillstand, the YETI starts rotating the feet servo clockwise
as seen from the front side. These rotations will result in two move-
ments:
Inarstphasetherigthsideofthefeetservoisrising,pullingtheouter
side of the right foot upwards. This action might bend the body to the
right, but this movement is impossible as long as the main part of the
weight is still resting on the inner side of the right leg.
At the same time the left side of the feet servo is lowering, pressing the
outer side of the left foot downwards. This action is lifting the left leg
upwards, bending the body to the right and transferring the main part of
the weight to the right foot.
If YETI raises his right foot a little bit too much, the left foot will bend
YETI’s body over the equilibrium point, causing the robot to fall down to
the right side. YETI must raise his right foot just high enough to prevent
the left leg from pushing him beyond the equilibrium. The closer the
body reaches the equilibrium, the greater percentage of the weight is
resting on the right foot and the easier the robot is able to move his left
foot.
At this point the legs servo is activated. The legs servo moves YETI’s
left leg forward as far as possible. While moving the left foot forward
from behind, the body will also be bended up to a position halfway the
left foot, but still following the line of the right foot. YETI is still balancing
on his right foot. As soon as the left foot has reached its ultimate
position, the robot raises the outer side of the left foot and
simultaneously presses the outer side of the right foot downwards.
These actions will move the body and its weight as well (including the
equilibrium point) from the right foot to the left one. Again we must be
careful to prevent YETI to move too far to the left, which would result in
falling down.
The movement phases will symmetrically be repeated for each
single leg.