Let's Make Robots! | RobotShop

LMRv4 Donor Appreciation Robot

Results: Donor Drawing Winners!

See the LMR Donor Drawing Winners - Seeedstudio Prizes page


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 May 1st, 2012 will be entered into a drawing to win one of five prizes generously donated by Seeedstudio!

We need a cool robot to pick the winners. 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.

RobotGrrl has offered to have the drawing made live on her weekly Robot Party after the May 1st deadline. The drawing will also be recorded for posterity.


  1. The challenger must set up a system that can pick a list of 10 names from a provided list. 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.

Update: Challenge Ends and Winner is Selected


Today is May 1st. Time to pick a winner.

It has been suggested that with two such great entries, why choose? If both contestants are ready and can be available for the Robot Party (this Thursday May 3rd at 8:00 PM Eastern/US), then let's have them both choose!

If there are no objections, I will select the first robot by coin toss. That robot will start the choosing, and will select three winners (1st, 3rd, and 5th) and two alternates (2nd and 4th). The other robot will select two winners (2nd and 4th) and three alternates (1st, 3rd, and 5th).

Update 2012-05-03: The drawing will be very late for RobotFreak (2 AM!), so his robot will not be picking live on the Robot Party, only Nils' machine will. However, RobotFreak will do a random pick of five winners/alternates, and will send me the video. 

BTW, the time will be 2 AM for Nils as well. Let's give him a hand for being so dedicated to stay up and help us celebrate!

Congratulations to both Nils and RobotFreak on really great robots! 


Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Are we supposed to actually build the robot or just give you ideas on how we would do so that you can build it?

Build. The ideas and rules where gathered here.


I know if this might sound silly but do we actually have to build one? The only robot that will actually be random will be one that uses a random number generator. A ball picking robot looks like it is random but people might say that you have placed a particular ball at a particular place or if a blower is used then they might say that you have stopped it so that your favored ball comes at the right place and that it is cheating. If a random number generator is to be implemented in a robot, it will be done in it's software and the hardware will just display the output. I can write a C++ program for you which uses a random number generator and picks the winner. It can have any number of participants as input and give any number of winners as output. The coding will be posted as well so that transparency is maintained. And you guys can enter the data yourself to make it free of any bias that I might have made. I'll make one anyways and you can use it if you want.
We are robot makers. How should we as LMR approach this draw if not with a robot?

Just back from holiday. So far, it looks like Nils is the only one working on a cool challenge robot. Come on, folks! May 1st is just around the corner!

Nils tells me his machine for making the draw is almost working. We are getting really close to the end. 

Won't anyone else get in the spirit and make a robot for the draw? It'd be fun to see what people come up with.

I'm working on a robot for the draw, too. Nothing spectaculary, only a simple robot arm. But it should do the job. The hardware is finished, but no programming has been done yet.