[Solved] Brain2 faulty MPU sensor
Brain2 has developed very annoying habit of slowly tilting the swashplate on elevator axis, making the helicopter more and more "tail heavy" in flight.
I started digging and logged inputs and outputs on all avaliable axes while holding the gyro firmly on the bench, without any movements or other inputs.
The elevator gyro keeps sensing arotation all the time, which is being compensated by growing amount of elevator output, which can be seen on the graph below
Is there a way of re-calibrating the sensor to bring this unit back to life?
And second quiestion - as original MPU6000 is not available anymore - can it be replaced with MPU6050? (Does Brain use I2C interface or spi?)
As we have always explained, the behaviour of the flight control unit when the model is stationary on the bench and cannot rotate on any of the three axes is completely different from the behaviour in flight when the model is able to rotate freely on all three axes.
When the model is clamped on the table every smallest signal generated by vibration, oscillation, flexing of the plastic skids or even sound (beep generated by the ESCs on motor windings) or by the "noise" of the transmitter potentiometers, is progressively increased in an attempt to rotate the model, but being clamped this does not happen and the signal continues to be increased in an attempt to start rotating the model. This 'continuous amplification' of the signal does not happen in flight.
Anyway, please can you send the configuration file of your Flight Control unit?
Why are you concerned about sourcing the components used in our flight control units?
Are you a manufacturer of other flight control units?
Are you a competitor?
Do you intend to make your own flight control unit?
Don't worry, I have no intention of manufacturing another FBL, there's already a lot of them and I wouldn't have an idea how to do it 😉
All I wanted to do is repair my Brain2. I can't source new, original InvenSense MPU6000 cause all shops say it's obsolete, although MPU6050 is easily attainable. That's why I asked if it can be replaced by 6050. (Interface is the only difference between them as far as I know - 6000 uses spi and i2c, while 6050 uses i2c only)
This was a faulty gyro, no doubt. When I changed "uni orientation" to "top left, wires back" this strange behavior switched to rudder axis.
And this unit made the helicopter fly unpredictable - it wasn't stable on elevator axis and pulled backwards ( when in "top up, wires front" orientation).
I found a damaged Brain1 and swapped it's MPU to this Brain2. Now with the "new" senor it seems to be working fine - it's been standing on te bench turned on for almost an hour now and no strange behaviors are present anymore. Of course it will be test-flown in the smallest, lightest and less powerful helicopter I have. And I'll never sell/give it to anyone.
I guess the case is solved then.
OK, although as we wrote the phenomenon you experienced was due to something else, but if you consider that you have already solved your problem for sure, better for everyone.
We consider this thread solved and closed.