FYI - Battery Tray and IMU

RichWest · Nov 1, 2015

Learned a lesson over this weekend's efforts to test a mod on my bird.

I was having some erratic flights, the bird was resonating while in a hover. Not severe enough to make it fly badly, but enough to notice all was not well.

My mod required that I access the guts often, underneath the battery tray. To help speed up the tweaking of the mod and then flight test, I only installed two of the four screw holding the battery tray area. It appears this was enough to allow vibration to resonate into the IMU. Which in turn caused the motors to compensate ever so slightly, basically a fight of flight.

Lesson, use all four screws to install the battery tray. These screws are holding the main board which is holding the IMU.

Good Luck!

Maddog · Nov 1, 2015

RichWest said:
Learned a lesson over this weekend's efforts to test a mod on my bird.

I was having some erratic flights, the bird was resonating while in a hover. Not severe enough to make it fly badly, but enough to notice all was not well.

My mod required that I access the guts often, underneath the battery tray. To help speed up the tweaking of the mod and then flight test, I only installed two of the four screw holding the battery tray area. It appears this was enough to allow vibration to resonate into the IMU. Which in turn caused the motors to compensate ever so slightly, basically a fight of flight.

Lesson, use all four screws to install the battery tray. These screws are holding the main board which is holding the IMU.

Good Luck!

Thanks- one of mine stripped out and I haven't been using it. Now to figure out how to best repair it.

erikgraham · Nov 1, 2015

Maddog said:
Thanks- one of mine stripped out and I haven't been using it. Now to figure out how to best repair it.

What got stripped? If it's just the screw, get a replacement at the hardware store.

Maddog · Nov 2, 2015

erikgraham said:
What got stripped? If it's just the screw, get a replacement at the hardware store.

Nope- the board it screws in to.

Guy Canavaggio · Nov 3, 2015

Same vibration, same error , found a mod where vibration absorbent rubber 3/16 thick is placed between the batrery tray and the main board thus making the bottom of the battery tray touch the rubber and secure the main board absorbing vibration . IT WORKS....

RichWest · Nov 3, 2015

Guy Canavaggio said:
Same vibration, same error , found a mod where vibration absorbent rubber 3/16 thick is placed between the batrery tray and the main board thus making the bottom of the battery tray touch the rubber and secure the main board absorbing vibration . IT WORKS....

Can you provide further details about the type of absorbing rubber?

Jubalr · Nov 3, 2015

RichWest said:
Can you provide further details about the type of absorbing rubber?

This is what was referenced by Ian. I picked some up and it works well..
http://www.amazon.com/gp/product/B006YJ82W4?psc=1&redirect=true&ref_=oh_aui_detailpage_o06_s00

User Name · Nov 3, 2015

Maddog said:
Nope- the board it screws in to.

Do you know if it's one that screws into metal, or just plastic? If it's just plastic, you could carefully put some epoxy in the hole (not fill it, just try to coat the sides, let it dry nice and hard and retap some threads. If it's metal, you could find a screw one size larger and, if needed, tap the threads to that size. If it's a metric screw, you can sometimes go to an inch screw to get one in between standard .5 mm metric sizes and vice versa.

Guy Canavaggio · Nov 3, 2015

This is the mod.

Duro Sheet (moon gel) Mod | 3D Robotics Drone Forum

Guy

Maddog · Nov 3, 2015

User Name said:
Do you know if it's one that screws into metal, or just plastic? If it's just plastic, you could carefully put some epoxy in the hole (not fill it, just try to coat the sides, let it dry nice and hard and retap some threads. If it's metal, you could find a screw one size larger and, if needed, tap the threads to that size. If it's a metric screw, you can sometimes go to an inch screw to get one in between standard .5 mm metric sizes and vice versa.

I think its the PC board. Either way, thats a great idea- I hadn't thought of that! Thanks, I'll try that.