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Simple co-ordinated finger movements by sending the same commands to all motors of the same function in each finger and thumb. The Dexhand is part of the Open Humanoid Robot Project - an #open #alternative to the commercial #humanoid #robots being developed by tech giants like #Tesla #Optimus If you’ve always dreamt of having your own humanoid robot that dream is within reach and uses only 20k USD of components. We are now looking for participants in the production of the first batch of DIY robots to feature 19 DOF hands, series elastic actuator driven arms and an articulated body that can stand, balance and move at over 25 km/h! Want to see if you've got what it takes? The V1 #DexHand is freely published and available for download at The parts can be printed on any extrusion printer and the hand uses less than 300 USD of components. The parasolid CAD model can also be viewed and downloaded for free on the cloud platform Onshape: Designed and tested for high speed printing using a diameter nozzle and layer thickness except for the tendon spools and split parts of the palm sections which benefit from printing at layer thickness or better. Tested in PLA, PETG and CF nylon. ABS is not recommended for the large pieces due to warping. To finish 3d prints to a high standard requires a fine sandpaper or emery board. Diamond coated steel nail files are a handy tool: Though my favourite diamond file is actually intended for maintaining whetstones, just a nice big expanse of diamond dust to use :-) - Amazon US: Additional components required are listed below. Please consider buying via the Amazon links where available to help fund the robot development. The biggest cost item are the 16 slim micro-servos that drive the fingers and thumb. In the US the discount code ROBOTSERVOS will take off 10% from the official Emax webstore: There are 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 standard micro servos are needed for wrist flexion and extension. Feetech SCS2332 - are recommended. 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 standard PWM servo for simplicity they can be substituted by any servo that fits inside the envelope 23.2*12.1*. The trade off is the reduction of the powered range of motion of the wrist to about half. 1 standard servo needed for axial wrist rotation (optional) Feetech SCS15 - or any servo that fits inside the envelope 40*20*. Reduces powered range of motion to about half and the loss of a continuous rotation option. The rest of the components are relatively inexpensive: 2mm diameter steel pins - alternatively cut lengths from a wire coat hanger or in Europe order direct from Otherwise kits are available on Amazon US: M2 screw and washer kits, or also in Europe from Amazon US: M2 brass threaded inserts M2 * 4mm long * Note that the type required has a plain section between the knurled ends to allow attachment of the tendon in the fingertip. Amazon US: Kite or fishing line for finger tendons - Sufix 832 is the best I know of for longevity, the 80lbs breaking strength is stiff enough to thread easily and most readily available on Amazon US: Slightly thicker kiteline for the finger ligaments and wrist tendons. Amazon US: Ball Bearings 6*10*3 - Need 50 for a hand, packs of 10 available which are enough for the sample finger. Amazon US: Ball Bearings 2*6*3 or 2*6*2.5 - Need 6 for the wrist Amazon US: Ball Bearings 15*21*4 - Need 4 for the wrist Amazon US: Ball Bearings 3*8*4 - Need 6 for the wrist Amazon US: M3 * 70mm caphead bolt (grade 12.9 ideally) Available from Amazon US in packs of 10: Follow @therobotstudio Get involved at
