fischertechnik ROBOTICS ADVANCED, Руководство пользователя

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TXT
Discovery Set
ROBOTICS
41
How does the robot find its way around the playing field?
Maybe you have wondered how the robot finds its way around the
playing field using the stripe codes on the sideboards. As a matter
of fact, this is not a simple operation, but it works according to the
following principle.
In fact the robot is capable of determining its position on the playing
field to an accuracy of approximately 2 cm and an angle of approx. 5
degrees based on the sideboards. For this purpose the robot measures
the height of the sideboards at various points and uses this height to
calculate the distances and then finally the angle and absolute position.
This process is known as triangulation.
The sideboards always have 3 black stripes with 2 white stripes in
between. One of the black stripes is wider than the other stripes. This
allows the robot to recognize which sideboard is which. All totaled there
are 5 different sideboard patterns, one for each side of the playing field
and one for the goal.
Moreover the robot uses the counting pulses from the encoder motors
to calculate the position and angle between triangulation operations.
This process is known as odometry. Odometry is more precise for
short times and distances. However it has the disadvantage that errors
accumulate in the course of time. For this reason the data obtained by
odometry is corrected using the data from triangulation.
The soccer robot program has two subroutines for these calculations:
the triangulation and odometry subroutines. If you would like, take a
closer look at them. But don't be alarmed! They look pretty complicated;
and they are.
If everything looks too theoretical for you, don't worry. Simply use the
program provided, be amazed at how it works and make a bet with your
friends, how many times the robot will have to try before making a goal.