Accelerometer not calibrating

[Alobidat]

Hi all,

Please excuse my newbie questions.

I am trying to upgrade my quad from a KK v5.5 controller (able to fly with no problems) to Multiwii using Arduino Mega 2560 R3 + custom shield and the following sensors:

1- 10DOF(axis) IMU L3G4200D+ADXL345+HMC5883L+BMP085 sensor module
2- GPS Module MT3329 SKM53

I uploaded the Multiwii code to my arduino after updating the config.h to enable my sensors and to define my XQuad
I finished wiring all sensors, ESCs and receiver, and can connect to MultiwiiConf version 2.0 and was able to calibrate my TX ranges.

I got reading in the Config GUI for my GPS, sensors and TX commands.
Status led (13) in the board is flashing in different rates all the time

Do I need to do any other setup?

Now I have two problems,

1- The Acc reading are crazy, and using the calibrating will bring all values to 0 for few seconds then crazy reading again.
2- When powering up the ESCs will ARM automatically (I am assuming telling from the beeps) which is wrong, also I could not make the motors to start.

I believe I am missing something or maybe my setup is not correct to begin with.

Any Ideas or things to look at?

Thanks.

[Alobidat]

Correction: I am using the latest code version 2.1.

[tovrin]

in the GUI, do you see any I2C errors? if so, check your soldering.
when powering on your quad using the LI-PO your ESCs will beep signifying their settings. this is normal.

your motors wont arm if the flight controller isnt working right.

post a screenshot of your GUI, and maybe a picture of your flight controller assembly.

[Alobidat]

It looks like I had a bad IMU, or I just damaged it, grrrr.

Waiting for my alternative.

[NikTheGreek]

Can you provide us a pic of those "crazy readings" !!

[chris ables]

Nik did you read this in the faq ? The ACC values are stuck to +/-400
This is one of the most common issue with ACC.
The accelerometers need to be calibrated at least once via the RC sticks combination (low throttle + pitch stick low + yaw full left).
Once this step is done, the accelerometer neutral value is stored in the EEPROM.
Without this step, the accelerometer values won’t correspond to anything, and sometimes there are anarchical bars in the GUI.
The values are typically 0/0/200 or 0/0/250 or 0/0/512 after a good calibration, depending on the ACC type.
( im also posting you something on the trimming post you have )

[doughboy]

It looks like I had a bad IMU, or I just damaged it, grrrr.

Waiting for my alternative.

unless you see it smoke, I don't think the imu can be damaged easily, so its likely a connection (like pullup resistors) issue. as someone else asked, if you see I2C errors, then your connection is bad. You should get absolutely 0 i2c error at all times.

since you wired it yourself, does the 10dof come with built in level converter? it does not have to have built in level converter, as long as the scl and sda lines are pulled up to 3.3v, you can set AVR to not use internal pullups and it will work fine.

[bill516]

I've got one of those types imu's and I had to change the address of the sensor, this might be a long shot as I am the only one with this problem that I know of. Click on the sensors tab then go down to the l3g4200d gyro, its about two thirds the way down the page. It probably says #define L3G4200D ADDRESS 0x69 and change it to read 0x68, save it and load the sketch to your board. If you have i2c errors has as already been mentioned then you wont get any sense from the GUI.

[justk1w1]

Alobidat,

Been through a couple of these problems:
1. Acc Crazy? Not sure how you have connected the Sensor board and whether you are using the I2C Gps, but I found that I had to put a level converter on the I2C bus to ensure the stability of the bus. I'm actually using the Mega and a I2c GPS (leostick) and a I2C sonar (cheap sonar that I have converted to a I2C Sonar and hacked and updated the tiny_gps code to support just the sonar without the GPS)
If you are getting I2C errors then one of the guys wrote a I2C_spy sketch (think it is a part of ardupilot) which you can upload to determine all the devices on the I2C bus - very handy little tool
2. ESC beeping? - I'm assuming that all you are getting here is a single beep every second or so - if this is the case then the ESC's that you have got do not support the 490Hz refresh rate that is now currently mandatory in 2.1 - I initially reverted back to MW2.0 with the patch for 200Hz esc while I waited for the new ESC's to arrive - I had to actually buy new Esc's, but the alternative to this would be to flash the Esc's that you have with SimonK firmware (if they are supported). While the ESC's are beeping you will not be able to arm the motors.