20kandroid - open source Humanoid robot project to build a full-size humanoid robot for $20k

An overview of the complete humanoid robot I'm presently putting together from existing prototypes from previous projects - like the balancing wheeled legs, the parametric face or the dexterous hand and arm project.

Even at low volumes this android can be put together for under 20k USD!

The #cad for the arm and hand is freely and publically available down to a parasolid level at:

The forearm and hand can operate as a stand-alone unit allowing unlimited axial rotation for rotational tasks like scrubbing.

Some notes on printing:

Designed and tested for high speed printing using a 0.6mm diameter nozzle and 0.4mm layer thickness except for the tendon spools and split parts of the palm sections which benefit from printing at 0.3mm layer thickness or better.

Test printed in CF nylon with 0.6mm nozzle and 0.4mm layer for structural components.

To finish 3d prints to a high standard requires a fine sandpaper or emery board.

The part links below will open to product pages that are related to building high quality robots.

Please consider buying via the Amazon links where available to help fund the robot development.

Though my favourite diamond file is actually intended for maintaining whetstones:

Additional components required are listed below.

The biggest cost item are the servos:

16 slim microservos like the Emax ES3301 (approx $6.6) are needed for a total of approx 100 - 200 bucks.

The hand in the video uses Emax ES3302 but any slim micro servo that fits inside the envelope of 23.2*9.2*24.1 will do.

Emax themselves make four variants at this size with plastic or metal gears and using either digital or analog control technology.

ES3301 (approx $6.6)
ES3302 (approx $9.2)
ES3351 (approx $8.5)
ES3352 (approx $12)

2 micro servos needed for wrist flexion and extension:

These are serial bus driven servos over allowing a greater range of controlled rotation.

They cost around 35 bucks each plus delivery.

If you prefer to use a traditional servo for simplicity they can be substituted by any servo that fits inside the envelope 23.2*12.1*28.5mm.

The trade off is the reduction of the powered range of motion of the wrist to about half.

1 standard size servo needed for axial wrist rotation:

The rest of the components are relatively inexpensive:

Otherwise kits are available on Amazon:

M2 brass threaded inserts M2 * 4mm long * 3.5mm
Note that the type required has a plain section between the knurled ends to allow attachment of the tendon in the fingertip.

Kite or fishing line for tendons and ligaments - Sufix 832 is the best I know of for longevity, the 80lbs breaking strength is stiff enough to thread easily and most readily available in the US.

Ball Bearings 6*10*3 - Need 50 for a hand, packs of 10 available which are enough for the sample finger.

Ball Bearings 2*6*3 or 2*6*2.5 - Need 6 for a wrist.

Ball Bearings 8x3x4 - Need 6 for a wrist.

Ball Bearings 15*21*4 - Need 4 for a wrist.

ptfe tubing 2mm OD 1mm ID, sold for 3dprinters.

[themagnushjort]

Interesting.
Looks kinda scary though, I would make it more stylized to avoid the uncanny valley but I'm not the person making this :)

[AssBurgerHD]

Really tight design, why the two seperate beams instead of one? Sorta a Segway ish design