Let's Make Robots!

LMRv4 Donor Appreciation Robot II


As most of you know, we are running a fundraiser to help cover costs for developing LMRv4. Visit our Donation Page for more info.

Anyone who makes a donation before June 15, 2012 will be entered into a drawing to win one of five prizes generously donated by Adafruit!

Adafruit Rocks!

Motor party add-on pack for ArduinoStarter Pack for Arduino (Includes Arduino Uno R3)Adafruit Motor/Stepper/Servo Shield for Arduino kitMintyBoost KitTV-B-Gone Kit


We need another cool robot to pick the winners. Sure, we could use Nils' machine or RobotFreak's robot, but where's the fun in that?

So here is your challenge.

The robot must be able to make random selections from a pool of names. There are five prizes, and just in case we want to pull 5 alternate winners. So we need 10 names picked.

The rules for the drawing will be that the first name picked gets their choice of the prizes, the second name picked gets their choice of the remaining, etc. So the robot challenge must be able to support that.

The drawing will be made live after the challenge deadline. The drawing will also be recorded for posterity.


  1. The challenger must set up a system that can pick a list of 10 numbers representing our donors. The list of names will probably be on the order of a few hundred.
  2. The system must provide a way to determine the order in which the names were picked.
  3. The system must be fair. (This may seem easy but it is hard to create a physical random number generator with a uniform distribution.)
  4. The system must use an autonomous robot as part of the process of picking a name. E.g., if a dice is used, a robot must throw the dice, or read the dice, or BE the dice :).
  5. The system must be as transparent as possible. E.g.. A robot printing out a name on a lcd is not very transparent unless you can show how the code works step by step as the choice is made.

OK. Get those thinkers thinking and make it happen! To be considered, you will need to post a link to a video as a comment to this challenge page. The video must show that your robot can meet the requirements in the rules above.

The winner will be selected by Nils and myself.

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Nils and RoboFreak set the standard the last time. I hope we come up with something out of this world to do the selection this time. Best of luck to everyone who it trying!!

So, why not give it a try yourself?

I already have a plan to make a True Random Number Generator but due to personal problems I can't start on any projects before 2nd of June (even my first project for which I have been brainstorming for over 2 months is delayed). So I'm out of the running for this time atleast.... :(

I haven't seen anyone stepping up to this challenge, but I am making an entry myself. Here's a hint...




My official entry into the challenge. This will be picking our donation winners, unless someone runs a dark horse last minute entry.

Robot Page: http://letsmakerobots.com/node/32962

Video: http://www.youtube.com/watch?v=auiep6AW-dc&hd=1