Using circuit scribe to reduce the cables?

Technology
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Hello guys, take a look at this:

Do you think it would be interesting to use this in order to draw the electrical connections ON the Poppy skeleton instead of cables. (small wires can be used to connect the extremities of the skeleton to the motor connectors for example). This could maybe reduce the weight, and give an artistic look to the robot, with the lines looking like veins maybe?
Also I am wondering if reducing hanging cables with this would not improve the repeatability by reducing the harmonics during the motion of the robot, since cables can move/ oscillate but this ink is static with respect to the Robot chassis.

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This is a good idea! We haven’t tried this yet, but it is a promising approach to get rid of cable problems.

The cables are so light that the harmonic problem you mentioned does not exist. However cables tend to wind up around articulations. With a lot of engineering we came up with good solutions for that but having the robot “cable free” would be a big improvement.

I am not sure how ink will stick on the 3D printed part. You can also consider conducting 3D printing filament. I saw this paper a while ago: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0049365
It looks like this site sells it: http://www.makergeeks.com/coabs3dfi10.html but the material has too high resistance to replace wires directly…

Another interesting project on printing electronics: http://www.cartesianco.com/, the resulting flexible circuit may be “glued” on the robot parts.

Finally, if replacing wires happen to work out fine, we could even consider getting rid of Molex connectors. The connectivity could be done directly on contact between the motors and the 3D printing parts (something like this). But there is a long journey before this :slight_smile:

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Sounds great! I just sent an Email to ask if the pen will write on 3D printed parts, as I understood, the ink would probably stick, the main issue is in the ball-pen not the ink. http://www.electroninks.com/faq/

If it works, we can imagine using a combination of both, the 3D printed ink on the extremeties of the parts just for connection points since it has high resistance. And then draw the lines between the points with the ink. As a result, no wires! Add to that a batterie and wifi and we’ll get a truly Wireless Poppy :smiley:

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To complete there is also maybe a problem with the current, it is not sure it will be possible to have 2-3A in such wire.

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Great idea! However, another issue is that you will still have to go over the robot’s articulations.

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True, I think for the current it should be okay, it depends on the surface but on a solid one I read that a line can conduct up to 800mA, so unless the 2-3A are going in one single line there should be a solution here. But going through the robot’s articulations seems tricky indeed…