I purchased the Pololu IMU and integrated it into the robot over the last few days. I was able to get the magnetometer and the accelerometers to work quickly with the supplied code. But I had issues with the gyro. After re-reading everything, I discovered that the gyro code provided is not a standalone gyro not the gyro on the IMU. They are the same part, but the I2C address is different. Quickly changing the address had that part up and running as well. Now I need to start the calibration process. I have hacked an old record player/turntable to calibrate the gyros. The accelerometers I can calibrate using the gravity vector (available anywhere gravity can be found). The magnetometers I can calibrate using the supplied code and check against a true north vector (from a sun shot) corrected by my local magvar.
Progress has been rather slow due to visitors and other home issues. This weekend is also shot due to a mini vacation. Summer is quickly passing by. Hope I make enough progress to stay on schedule with data collection before the snow starts to fly.
Hi Skye!
I recently got the IMU v2 from pololu. I couldn’t get the gyro working either. Above you mentioned that you were able to get it to work after changing the I2C address, I’m wondering what address did you use? And how did you figure out that the address is different from the one given by them? Thanks!
Gerry
It has been a while since I figured out this problem, but I think I figured it out from analyzing the datasheets and the schematic. The code on the Pololu site was for the individual sensors. When they put the two on the same board, the address conflicted and they moved one. Of course they did not mention this on the product page. If you send me an email to Skye at FLL-FREAK dot com, I will send you my updated code. In the mean time, I will try to find time to clean it up and post it on my website.
Here is the code. Inside this stuff will be the addresses I used for each part.
http://www.fll-freak.com/misc/IMU.zip