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Pi Noon: The Right Stuff

Pi Noon, 2018

Aim of the challenge

  • To burst your opponent’s balloons.

Control Method

  • Remote-controlled

Time Limit

  • 3 minutes per duel


  • Two robots will face off against each other in a non-destructive duel which will test the driving skills of the operator and the manoeuvrability of the robot.
  • Robots will be armed with a pin on the end of a metal wire and must use this pin to burst balloons attached to the other robot.
  • For Schools/Kids Clubs, there will be 3 balloons per robot.
  • For the second day, Beginners will be provided with 5 balloons, Intermediates 4 balloons and Advanced 3 balloons. By using this ‘handicapping system’, we hope to even the playing field!
  • The duels will take place inside an arena with a short wall around the edge to prevent robots from leaving the arena.
  • Competitors are NOT allowed to enter the arena at any time (although judges can when the robots are static).  Robots must be driven to the edge if adjustments to the wire attachment is required.  Entering the arena may result in the loss of the duel.
  • You must not intentionally ‘spin on the spot’; you will receive a warning if the judge deems you are doing so, with a second warning resulting in forfeiting the duel.
  • In the event of neither robot winning the duel outright after 3 minutes, the challenge judge will make a decision based on control and ‘aggression’.
  • Intentional damage to another robot will result in disqualification. It is up to the driver of each robot to ensure that no damage is caused.
  • The decision of the judge is final.
    • Please don’t argue – remember, this is supposed to be fun.
    • It is recommended that someone from your team records your duel, for example with a mobile phone, so that the judge can benefit from the photographic evidence if the popping is ‘close’.
  • Due to the number of competitors, some robots may receive a ‘bye’ to the next round. This will be at random and announced well in advance of the competition.

The ‘Attachment’

  • Your robot must be able to hold a wire approx 3mm (measured to be 2.95mm, but you should allow at least 3.1mm) in diameter, 1cm off the ground.
  • We will provide a 1cm plastic cube for the judges to use to ensure the distance from the ground is consistent.
  • We recommend (but do not mandate) using an electrical connector block for the attachment. We can provide one free-of-charge for you to use.
  • The following is a diagram of the attachment attached to an example robot followed by a photograph (click to embiggen) of the real thing:

  • You can see rough renders of the new attachment below and you can download a zipped SVG of the attachment here. Our attachments will be cut out of wood, rather than perspex, to reduce the weight above the robot.
  • The wire must be attached to the front of your robot, in the centre without anything further forward than it.
    • The wire will be about the weight of a half coat hanger.
    • The wire will be shorter than previous years in an attempt to avoid over-balancing smaller robots.
    • The wire must be fixed so that it is not angled in relation to the floor. i.e. the wire must be 90 degrees perpendicular to the floor. This is to ensure that the height of the two sets of balloons are approximately the same.
    • The wire will be fixed onto your robot, by the judges, before each duel.
    • The wire will only be on the robot during the duels in which you take part.
    • If the wire falls off the robot then you will be allowed to re-attach it up to a maximum of 2 times.
    • If the wire falls off a 3rd time, you will be judged to have lost the round.
    • Only the competition judge may enter the arena to retrieve the robot and attachment.


  • The winner of each duel will be awarded 50 points, and will gain entry into the next round.
  • 40 points will be awarded as a result of a ‘bye’ or ‘no show’.
  • 125 bonus points will be awarded to the winner of the grand final – i.e. First place.
  • 100 bonus points will be awarded to the runner-up of the grand final. i.e. Second place.
  • 50 bonus points will be awarded to the winner of the 3rd-place final. i.e. Third place.
  • 25 bonus points will be awarded to the runner-up of the 3rd-place final. i.e. Fourth place.


  • The ‘attachment’ may cause robot instability by shifting the centre of gravity upwards. Be aware of this when designing your robot. You might think about adding optional weight to the rear of your robot to balance it, for example.
  • It is essential to ensure that the attachment holder (e.g. an electrical terminal block) is held securely onto your robot. Tape is not recommended as the wire tends to swivel in place.
  • You do not have to use the attachment holder supplied by PiWars, however we strongly recommend ensuring that the attachment doesn’t allow the wire to ‘spin’ as it makes the centre of gravity shift and makes aiming very difficult.
  • There may be spiked obstacles in the arena, although the central pyramid from 2018 will not be used.
  • Here is a video of the 2018 final:

Ask Questions and Discuss

You can discuss this challenge and ask questions on the discussion forum or via Discord chat.