• Jaú posted an update 5 months, 2 weeks ago

    Dear Community
    I am building the InMoovs right arm for the graduation project at my highshool in Zurich, switzerland. More specifically my goal is to control the arm via two devices. The first one is the EEG-headset “MIndWave” from the company “NeuroSky”, which measures the electrical signals in the brain and can hence tell whether the person wearing it is mentally focused or rather relaxed. The other device is a armband which measures the muscle activity at the forearm and is able to distinguish five different hand gestures. By receiving the signals from these two devices with an arduino board I hope to achieve some sort of contactless control over the InMoovs arm. Right now I am facing a hardware problem though which most likely will inhibit the development of my project.
    When trying to connect the right forearm to the right bicep i realized that I had neither of the two bolts, needed to connect “EllbowShaftGearV1” and the two “LowArmSidesV1” ‘s.
    In the pictures attached to this post one should see the two bolts I am talking about. One of the bolts seems to made from a polyetherimide material, presumably PLA or ABS so I assume that there is an STL somewhere. Could anyone tell me where I can find this STL file for that bolt in the picture attached in the post? The second bold seems to be made of metal. Is this a customized bolt or a standard one which I could order somewhere? If it is the former, does anyone know the physical measurements and the material of it?
    I would be really happy if someone could enlighten me with their experience and knowledge.
    Thanks in advance!

    • It is very important to use the Hexagon socket head cap screws – zinc-plated – DIN 912 – 12.9 screws, they have to be 12.9, because of of the distortion of the parts and the torque set on them through the gears and servos.

      But all jokes aside, they are just regular M8 bolts, nothing special. With a bit of research you should be able to find that out. On those joints there cant be printed bolts, that would not be logical. So just go to your local hardware store and buy some bolts.

      • Well okay then I will have them manually manufactured by a special craftsmen we have in town with zinc-plated titanium.:D

        No man thank you a lot! I guess I didn’t saw the forest because all of the trees, as we swiss describe the phenomenon of overseeing something rather obvious:)