Robotics Invention System v1.0
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Challenge 1: Outback Tracker

  The Challenge is to make a robot with touch sensor
  control that can complete an obstical course.

Design:

  * needs two touch sensors
  * needs two motors
  * moves forward and backwards
  * turns

  The best base for this robot is the Pathfinder design
  which can easily turn on the spot as well as move forward
  and backwards.

  In designing the sensor cluster, the design needed two
  large bumpers for the front of the robot which will
  release the touch sensors when pressed and need to be
  independent of one another as well as both being able to
  be pressed at the same time.

  My sensor cluster has two vertically aligned bumper pads
  which release the touch sensors when pressed and are held
  closed by rubber bands. Its light and simple and doesn't
  foul easily on obstacles.

Programming:

  Program Outback Tracker to respond to touch by:

  * moving forward when both sensors are pressed
  * turning on one motor when one sensor is pressed
  * stopping when neither sensor is pressed

  Using the example program provided, I set the touch
  sensor watchers to reverse and turn the robot whenever
  each sensor is released, turning the robot away from an
  obsticle. I made two macros for the reverse and turning
  commands just to keep the code simple and can be reused
  in other robots.

  In order to make the robot stop when both sensors are
  released, each sensor watcher checks the status of the
  other sensor when pressed. If the other sensor is also
  released it will simply stop, otherwise the robot will
  reverse and turn away from the obsticle.

Comments:

  This robot performed well when sent out into the house on
  its own, being able to bump its way around the house
  'feeling' its way along skirting boards and furnature.

  The only problem with this program is that if it gets
  caught in a corner it can bump back and forth forever.

  Perhaps a further improvement on this program is to
  randomly change the amount of turn it does when it
  reverses away from an object. This would allow it to
  search out from an obsticle in a wider pattern than a
  fixed turning angle (prevents it bouncing repeatedly back
  and forth off two sides of a corner).

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AraKaraath halfDragon                arakaraath@hotmail.com