Using MiniIMU-9 v5 for heading reference

I have built an autopilot that has been working for 4 years using the IMU-9 v3. In rough water the tilt compensation is inadequate. I just purchased the IMU-9 v5. I have run the examples and the board works fine. The Pololu library used with the v3 included code to provide a gyro - accelerometer stabilized heading. That level of code does not seem to exist for the IMU-9 V5.

Am I overlooking something or am I correct in concluding that the Pololou Resources no longer support an attitude and heading reference system (AHRS) for the IMU-9 V5?

Do you have suggestions on how to make a AHRS from the IMU-9 V5.

You might try the RTIMULib AHRS. It works very well and I think it will work for that sensor – my experience with it is documented in this post: State of the art AHRS for $25

Thank you for the info. I’ll see if I can use that library with the IMU V5 sensors.


We are planning on releasing a version of the existing AHRS software that works with the AltIMU-10 v5 soon.


I took a look at RTIMULib and it does not appear to support the exact sensors used in the IMU-9 V5. However, similar models are supported and I don’t think it would be difficult to modify the code appropriately. If you decide to go that route and need help, let me know, although I don’t have an IMU-9 V5 to test it with.

Jim, Thank you for the offer. I would like some help. Looking at the RTIMUlib I see it supports a mode operating on a PC but I don’t know what run environment I need to use to use RTIMUlib. Once I get past that I could test my Pololu IMU-9 V3 which I think the RTIMUlib supports. Then I could try to use the V5 but would probably need help to modify RTIMUlib. Here is a preliminary calibration using the Calibrate example with data copied to Excel.

Ranges are pretty close but I was quite surprised by the variability of the offset.

Jack Edwards


Sorry, but I don’t understand your post. If you want to use RTIMULib with your sensor, you would do that with an Orangutan or other ATMega328 processor board, using the Arduino environment. Have another look at my post on getting it running with the altimu10.

To make RTIMULib work with the newer sensors would probably require changes in the part of the code that directly reads data from the sensor.


Sorry looks like I missed your most recent post. Previous post came to my email inbox. But this one didn’t. I’ll take another look at your original post and see if can follow your example more closely.

Jack Edwards

We updated the MinIMU-9 -AHRS program to work with the v5 IMUs.