Dead IMU AGAIN

Pedals2Paddles · May 14, 2016

You may recall last month, one of the IMUs in my Solo died. It was a month old and failed. 3DR replaced the solo under warranty rather quickly, so I was ok with it. Now, a month later, the same thing is happening. I went out this afternoon to fly and was greeted with "Calibration Error" again. Same thing as last time. No amount of restating or factory resetting is fixing it. I opened a ticket with 3DR again, but of course have to wait for Monday.

Why are my IMUs failing???? Is this a thing, or am I the only one this happens to?

RichWest · May 14, 2016

Pedals2Paddles said:
Why are my IMUs failing???? Is this a thing, or am I the only one this happens to?

Must be your magnetic personality....

I only know of a handful commenting that their IMU failed, your one of them.

Pedals2Paddles · May 14, 2016

Must be! How are these IMU constructed and what could be damaging them?

SPP · May 14, 2016

Very strong magnet ?

pete · May 15, 2016

thanks for the tip, I've been carrying this strong magnet packed next to my Solo for over a month now, luckily no issues with IMU.

that magnet is really "vicious", when I put it on my car, I need both hands and little bit of fight to get it off.

on the other hand, I do have another brand new Solo back at home that came with faulty IMU out of the box, never flown that one, couldn't pass the pre-flight checks as the level calibration failed every time. I didn't get a chance to deal with it yet until I get back home but I don't like the idea of sending it from Australia to San Diego and receiving refurbished second hand Solo instead of a brand new that I paid for. it's bit annoying as I bought it as a spare Solo for peace of mind in case I lose or crash my original one on the trip and I thought it was worthwhile extra investment/insurance considering the cost of the trip.

is it possible to replace IM unit on a Solo ? IMU is part of the Pixhawk, right ? Swapping the Pixhawk should solve the problem, or am I missing something ?

service manual suggests on page 42 that Pixhawk is replacement part available for purchase, there are even instructions in the same manual on how to replace it.
https://3dr.com/wp-content/uploads/2015/10/Solo_Service_V3a_10_30.pdf

SPP · May 15, 2016

IMU is a solid state, IC shape , something like this ..........

10DOF IMU MPU6050 HMC5883L BMP180 - CSG Shop

Inertial measurement unit - Wikipedia, the free encyclopedia

An inertial measurement unit (IMU) is an electronic device that measures and reports a body's specific force, angular rate, and sometimes the magnetic field surrounding the body, using a combination of accelerometers and gyroscopes, sometimes also magnetometers. IMUs are typically used to maneuver aircraft, including unmanned aerial vehicles (UAVs), among many others, and spacecraft, including satellites and landers.

Indeed there are two magnetometers in Solo, not the digital compass one.......... IMU and FMU use.