RP1 droid
Just for fun
Since getting my Ender 3 printer I had been looking for something fun that I could design and print from start to finish. When I came across a bearing that could print fully functional with no supports it gave me an idea. After sketching around in my notebook I decided to create a little spherical droid that reminded me of a mix between BB-8 and the giant robot from The Incredibles.
The cutaway of my final CAD model shows some of the mechanical details required to make this robot work. It took a couple prints to tune in the details for the ball and ‘C’ joints in the legs. I wanted there to be enough friction that the legs would stay in the position I placed them and hold the weight of the model, but there still needed to be enough clearance to snap together. The ‘eye’ feature also required some consideration of tolerances and alignment.
When those details were finished I thought it would be fun to do some decent renderings. I wanted to create some visuals that would show the little droid in the environment and appearance that I had imagined it.
Below you can see the progress of the first print attempt. The larger parts turned out well, but some of the smaller components needed to be revised. The bearing needed to be printed separately without supports. I also needed to adjust the design of the part to receive on of the magnets that would hold the model together.
Not all of the ‘arms’ turned out in the first print. I had to slow down the flow rate to around 50 percent in order to get good bed adhesion on the first few layers.
RP1 closes up into a sphere that fits into the palm of your hand.
Three magnets hold the head to the base. One is placed in the bearing. The other two are used to index the open and closed positions along the central shaft.
All-in-all this was a very fun little project. The final print turned out well and the renderings help complete the process of imagination. After a few small tweaks I plan to put the model on Thingiverse for others to try.
