Let's Make Robots!

repBug, 3d printed hexapod


Hello everyone !

After spending more than a year tinkering with my 3d printer, I am finally moving on to printing some fun stuff: hexapods! 

 

So these are the very early stage of repBug a reprapped mini hexapod:

Some features:

- open source design (will post the link to the github repository soon)

- parametric (modelled in openscad)

- relatively cheap (<200 euros, all included, hopefully)

- showcase the advantages of 3d printing

Some more details :
muscle: HXT900 micro servos ->9 grams each (X21)
brain : RaspberryPi or BeagleBone -> 30 g
skeleton: small 3d printed parts (PLA plastic), sturdy yet light ! -> 10 g per leg
eyes: small cheap chinese webcam , without casing ->3g

 

Overall design (far from final)

openscad view of prototype

 

 


 

Update 02/09/2012

First print tests :


 


 

Update 10/09/2012

3d printed parts
- I moved on to fully 3d printed servo couplings: all the parts that would require servo horns have now a toothed inner profile, and it works !! So this means : no more forcing leg parts onto shaft and damaging them, aswell as a lot of weight and complexity gained ! 
- redesigned /refined almost all the parts, making them as lightweight as can be, while still keeping them sturdy (usually 5 mm thick)
- created and printed a "testing rig" : just a few printed pieces and a piece of wood, to suspend a leg duo for movement tests 

Electronics:
- in the pictures you can also see the RaspberryPi that is going to be used as "brains" for size reference
- instead of going with a Pololu Maestro
(http://www.pololu.com/catalog/product/1356)I decided to use two  +Adafruit Industries  16-Channel PWM driivers (https://www.adafruit.com/products/815)
while this will take up a bit more room, and will require more hand tuning it gives me 32 channels for half the price ! 
- had a very big "do'h" moment when I realized I don't have enough rigid cables for prototyping even two servos :)

dual leg test rig


Comment viewing options

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

Collected! When I'll get my 3D printer, for sure I'll build those legs! Thanks for sharing!

I'm curious about building a hexapod with the little 9g servos (using the same in a current project) and printed parts (just recently got access to a reprap).Good choice of colour for your prints, I was using the same/similar (orange PLA from faberdashery) last night to print something for the house. Please keep us updated and post a video of repBug's first steps.

Looking forward to see your process.