Mechanical interférence in Webcam fixing in the poppy head

Technology
1

Hi,

I just finished to assemble all the electronic & mechanical parts in the head and there is an interference between the head of the M2.5 screws to fix the camera support and the webcam board itself

DSC_0047 - copie.jpg1024×678 174 KB

It’s a bit sensitive because the screws are metallics and they touch the webcam pcb, a capacitor is gone away due to this on mine… (still working, probably power filtering) and a short circuit can easily appear…

I fix it using spacers (bic tube 2mm cuts)…

DSC_0046 - copie.jpg1024×678 210 KB

Maybe the support have to be redesigned with higher spacers here and maybe change the screw type (plastic ?).

Note : blue traces are normal loctite threadlocker…

2

Indeed the board touch the M2.5 bolt head but I do not remember it was a problem leading to potential short circuit.

Can you show me which component you think can be damaged ?

3

On my webcam, the component is damaged (now off the board), and I had to :
reduce the head height,
use plastic spacers,

in situation now with spacers

poppy - interference webcam.jpg1024×678 114 KB

Damaged component (capacitor I presume, webcam is still working) indicated with an arrow

poppy - interference webcam - zoom.jpg1024×768 140 KB

I tryied to resolder it with binocular scope but without success, I’m not so confident with SMD under 0603… :relaxed:

4

Ok …

I for me the contact was only with the big capacitor shell. I will create a fix.

Can you give me more info:

  • What is the size of the spacers you added ?
  • If your webcam is still working, can you verify if the head_face part is visible in the camera field ?
5

The “big capacitor shell” is a 12.000 MHz crystal :blush:

I use homemade spacer around 2 mm height, but I had to file down the allen screw head to be sure avoiding contact,

To avoid using spacers and keep the webcam in place, I would prefer use pan head plastic screw but I have not this sort of flat plastic screw

The webcam is still working, and the head_face part is not visible in the camera FOV (neither the screen part)

6

Ok so I opened our Poppy head and indeed the bolt is touching the CMS capacitor.

Instead of offsetting the camera as your spacers do, I moved upward as much as possible (1.5mm) the M2.5 bolt but normally, the bolt head should be juste above the camera PCB.

I created a new release:

Thanks Lionel for raising this embarrassing bug.