Let's Make Robots!

The Write LMR Challenge

The rules here are simple:

  • Make a robot that one way or the other writes either "letsmakerobots.com", or "LMR" the way you like it.
  • Shoot it on video, enter it as a robot.
  • Best entries will be promoted / used to promote LMR - Fame, envy, marvel, admiration and respect is the prize!

Your robot can shape the letters in clay, burn it on your sisters dog with a laser, build them out of breadcrumbs.. or draw it with a pencil on a piece of paper. Anything goes, as long as the letters are clearly written, and the video shows the progress.

Sample code is VERY welcome - perhaps this can be done simple by a "start-here-robot" - that would be way cool, and with some simple code that others could adapt and try at home!

Make sure that you have plenty of light on the video - best shot outside in daylight - it is going to be featured, so we need it to be sunny ;)

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I've pretty well sorted the font to keep the letters vertical instead of radiating outward from the centre. But in this attempt I did not allow enough time from when the pump first starts to when it's actually writting. It takes about 1/10sec for the water to start flowing. Once I've sorted the new nozles out to increase the pressure I'll probably have to adjust it all anyway.

how about a sensor that detects when the water flows, ie two pins at the nozzle that measures resistance,or one of those switches that have the long metal  bar that will get pushed out of the way from the water? Or is this all just overkill when you can just use a delay?


The time it takes for the water to reach the nozzle is pretty constant. When I changed the code for the two colours I didn't allow for the pumps stopping and starting again. For example, in the video, The R starts up higher than it should because I forgot to add the delay. Once I was on the beach it was too late to change the code.

Partial success! My new font seems ok but the two new nozzles on the cannons have a slightly larger hole which is dropping the pressure. The letters are not as high as they should be. See the video for a sneak preview of SplatBot MkII.


Wow, so nice, so cool!! I have nver seen anything like this.

Let me be the first one to comment "Demolition Man" :)

An arty suggestion: Let the font be in one color, but add a square around the text in color 2. ANd to look really cool, Start by making the square! :)


Can't wait to se the final work, thanks ever so much for sharing progress, it's highly entertaining and inspiring!!

 (I'd really wish it was my project!)

I hope this will inspire your creativity. As for the square, I'll give it a go but I might set it up with a different font for writing on a wall. I don't know how square it'll be after translating it to allow for the radial component. We'll just have to see. I'haven't found a wall that I'm allow to discolour yet. At least the ocean cleans up my mess on the sand.

I considered a wall but as the water runs down it will ruin the letters. The other thing I was considering was visibility. The water shows up well on the road.

I'm now replotting the text to compensate for the radial output.


The top shows the points plotted against servo positions.

The bottom shows how it should hopefully look.

This should make a big improvement on the next video.

This is SplatBot's 9th attempt at writting LMR, the wind wasn't helping so I'll try again on a calmer day. I'm also changing the font to try and compensate for the radial movement of the gun.

very good endeed!   congrats  ;)

perhaps you could try a wall instead of the floor?