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The robot

 The robot on October the 1st 1999
First meeting after the rules are published ! We have decided there the general outline of our robot.

  Simplicity => Small modules

In view of the distance between the members of the team (at most 500 km), in view of our finances (no sponsors for the moment), in view of the equipment we have (yes, we're gonna buy a soldering iron!), making many small modules seemed to us easier than a unique big robot.

Thus, we will make a main robot quite restricted and many MIO (*) aimed at blowing up the balloons.

The MIOs may be realized separately.

(*) MIO = Mobile or Immobile Object , word used to talk about the modules that do not carry the opponent's beacon. The main robot has to carry this beacon.

  The theme => the carrousel

We have been inspired by the theme of the competition (the Fun fair) to make our main robot.

It will look like a carrousel (a real one with horses turning around! so lovely :-) ). At the bottom of the carrousel, the area will be divided in 8 parts. In 6 of these 8 parts, a MIO will be placed. The 2 remaining parts are reserved for the carrousel propulsion. At the beginning of the match, the 2 MIOs in front of the inclined planes will leave the main robot. The carrousel will rotate of 45 degrees and 2 other MIOs will leave and so on. After dropping all the MIOs, the carrousel will go down the hill to leave the departure area as the rules mention.

The carrousel is therefore the most difficult mechanic part of our robot.

  Some technical choices
  • The mind
    The robot and the MIOs will be driven by a PIC or a 68HC11.
    Regarding our tests on Laughing Pic (see explanation in the technical database), a PIC seems to be powerful enough for simple acts.

  • The start
    A light sensor is a simple way to start the MIOs leaving the carrousel. We have to specify where this sensor will be placed so that the modules start all with the same principle.

  • The sensors
    It will be interesting to have MIOs different from each other. This will besides increase our chances of success. We would like to put on our modules different sensors : Infrared beacons, line follow-up (2 balloons are accessible with this method), side follow-up (3 accessible balloons), etc...

  • Boom the balloons !
    To blow up the balloons, the tests we made showed us that needles require a certain speed and that the balloons may move and draw aside. We will therefore prefer a "hot spot" system. We tested on a balloon and it seems to work pretty well! We have now to find what will burn the balloon. A resistive wire?
  1st prototype made after the meeting
Prototype châssis
Prototype of the frame of a small module



Prototype passage colline
Climbing the hill
The modules frame :
  • Aim
    Build a frame prototype to see if a MIO made with a servo-motor is viable.

  • Restraints
    -max size 15*15*15 cm (fixed by the rules)
    -has to fit in a sector of the carrousel
    -ground clearance of 2.5cm or adjustable to be able to pass the hills (not taken into account in this proto)
    -fast enough to cross the playing ground in less than 1:30 min ;-)
    -enough torque to climb the hill.

  • Realization
    The frame is made with aluminium bars, a ball at the front, 2 servo-motors fixed at the rear, and small plastic wheels.

  • Tests carried on
    The board of Laughing Pic (see in the Technical DB) is put on the frame. Tests of the speed on a flat area, rotation, hill climbing, crossing the ditch... have been made.

  • Conclusions
    The torque is enough. The mobility seems OK. But neither the speed, nor the adherence are satisfying. The MIO is to slow and spins in the turns. Bigger wheels, more flexible, seem essential. But the room lacks and we may need to have only 6 parts instead of 8. Nothing is decided yet, next on the following Fribotte meeting !

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Last modified on January 30th 2000