# Difference in IMU characterization - 42688 p on voxl

Source: https://forum.modalai.com/topic/2008/difference-in-imu-characterization-42688-p-on-voxl
Category: Flight Core and Legacy VOXL (https://forum.modalai.com/category/9/flight-core-and-legacy-voxl)
Tags: voxl-flight
Posted: 2023-03-28 21:14:58 UTC by Jagatpreet Singh Nir
Replies: 1 · Views: 1253

## Jagatpreet Singh Nir · 2023-03-28 21:14:58 UTC

I was trying to understand the noise characteristics of the IMU - ICM 42688p on Modal AI M500 drone that has a VOXL  board . I am trying to find the best IMU that I can use for my VIO application. I have  another board with the same IMU - ICM42688p on it.

I collected stationary data for several hours on VOXL board and DK42688 board that I ordered and then plotted the allan deviation plot as shown in the figure. I am getting very different results for Allan deviation between VOXL and DK42688 board. 
For comparison I also plotted Allan deviation of VN100 IMU (https://www.vectornav.com/products/detail/vn-100). 

Can someone explain why the VOXL-IMU0 has more noise? Are there any settings which need to be done so that I get a similar behavior from DK42688p board?![comparison_voxl_icm42688p_vn100.png](https://forum.modalai.com/assets/uploads/files/1680038141020-comparison_voxl_icm42688p_vn100.png)

## Reply by Chad Sweet (ModalAI staff) · 2023-03-29 05:12:55 UTC

You should compare the settings as configured in the code [here](https://gitlab.com/voxl-public/voxl-sdk/services/apq8096-imu-server). We provide the code so you can fork and implement your own configuration if needed