imu内参标定，allan方差分析，imu-utils

# imu_utils A ROS package tool to analyze the IMU performance. C++ version of Allan Variance Tool. The figures are drawn by Matlab, in `scripts`. Actually, just analyze the Allan Variance for the IMU data. Collect the data while the IMU is Stationary, with a two hours duration. ## refrence Refrence technical report: [`Allan Variance: Noise Analysis for Gyroscopes`](http://cache.freescale.com/files/sensors/doc/app_note/AN5087.pdf "Allan Variance: Noise Analysis for Gyroscopes"), [`vectornav gyroscope`](https://www.vectornav.com/support/library/gyroscope "vectornav gyroscope") and [`An introduction to inertial navigation`](http://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-696.html "An introduction to inertial navigation"). ``` Woodman, O.J., 2007. An introduction to inertial navigation (No. UCAM-CL-TR-696). University of Cambridge, Computer Laboratory. ``` Refrence Matlab code: [`GyroAllan`](https://github.com/XinLiGitHub/GyroAllan "GyroAllan") ## IMU Noise Values Parameter | YAML element | Symbol | Units --- | --- | --- | --- Gyroscope "white noise" | `gyr_n` | <img src="https://latex.codecogs.com/svg.latex?{%5Csigma_g}"> | <img src="https://latex.codecogs.com/svg.latex?{%5Cfrac%7Brad%7D%7Bs%7D%5Cfrac%7B1%7D%7B%5Csqrt%7BHz%7D%7D}"> Accelerometer "white noise" | `acc_n` | <img src="https://latex.codecogs.com/svg.latex?{%5Csigma_a}"> | <img src="https://latex.codecogs.com/svg.latex?{%5Cfrac%7Bm%7D%7Bs^2%7D%5Cfrac%7B1%7D%7B%5Csqrt%7BHz%7D%7D}"> Gyroscope "bias Instability" | `gyr_w` | <img src="https://latex.codecogs.com/svg.latex?{%5Csigma_b_g}"> | <img src="http://latex.codecogs.com/svg.latex?\frac{rad}{s}&space;\sqrt{Hz}" title="\frac{rad}{s} \sqrt{Hz}" /> Accelerometer "bias Instability" | `acc_w` | <img src="https://latex.codecogs.com/svg.latex?{%5Csigma_b_a}"> | <img src="http://latex.codecogs.com/svg.latex?\frac{m}{s^2}&space;\sqrt{Hz}" title="\frac{m}{s^2} \sqrt{Hz}" /> * White noise is at tau=1; * Bias Instability is around the minimum; (according to technical report: [`Allan Variance: Noise Analysis for Gyroscopes`](http://cache.freescale.com/files/sensors/doc/app_note/AN5087.pdf "Allan Variance: Noise Analysis for Gyroscopes")) ## sample test <img src="figure/gyr.jpg"> <img src="figure/acc.jpg"> * blue : Vi-Sensor, ADIS16448, `200Hz` * red : 3dm-Gx4, `500Hz` * green : DJI-A3, `400Hz` * black : DJI-N3, `400Hz` * circle : xsens-MTI-100, `100Hz` ## How to build and run? ### to build ``` sudo apt-get install libdw-dev ``` * download required [`code_utils`](https://github.com/gaowenliang/code_utils "code_utils"); * put the ROS package `imu_utils` and `code_utils` into your workspace, usually named `catkin_ws`; * cd to your workspace, build with `catkin_make`; ### to run * collect the data while the IMU is Stationary, with a two hours duration; * (or) play rosbag dataset; ``` rosbag play -r 200 imu_A3.bag ``` * roslaunch the rosnode; ``` roslaunch imu_utils A3.launch ``` Be careful of your roslaunch file: ``` <launch> <node pkg="imu_utils" type="imu_an" name="imu_an" output="screen"> <param name="imu_topic" type="string" value= "/djiros/imu"/> <param name="imu_name" type="string" value= "A3"/> <param name="data_save_path" type="string" value= "$(find imu_utils)/data/"/> <param name="max_time_min" type="int" value= "120"/> <param name="max_cluster" type="int" value= "100"/> </node> </launch> ``` ### sample output: ``` type: IMU name: A3 Gyr: unit: " rad/s" avg-axis: gyr_n: 1.0351286977809465e-04 gyr_w: 2.9438676109223402e-05 x-axis: gyr_n: 1.0312669892959053e-04 gyr_w: 3.3765827874234673e-05 y-axis: gyr_n: 1.0787155789128671e-04 gyr_w: 3.1970693666470835e-05 z-axis: gyr_n: 9.9540352513406743e-05 gyr_w: 2.2579506786964707e-05 Acc: unit: " m/s^2" avg-axis: acc_n: 1.3985049290745563e-03 acc_w: 6.3249251509920116e-04 x-axis: acc_n: 1.1687799474421937e-03 acc_w: 5.3044554054317266e-04 y-axis: acc_n: 1.2050535351630543e-03 acc_w: 6.0281218607825414e-04 z-axis: acc_n: 1.8216813046184213e-03 acc_w: 7.6421981867617645e-04 ``` ## dataset DJI A3: `400Hz` Download link: [`百度网盘`](https://pan.baidu.com/s/1jJYg8R0 "DJI A3") DJI A3: `400Hz` Download link: [`百度网盘`](https://pan.baidu.com/s/1pLXGqx1 "DJI N3") ADIS16448: `200Hz` Download link:[`百度网盘`](https://pan.baidu.com/s/1dGd0mn3 "ADIS16448") 3dM-GX4: `500Hz` Download link:[`百度网盘`](https://pan.baidu.com/s/1ggcan9D "GX4") xsens-MTI-100: `100Hz` Download link:[`百度网盘`](https://pan.baidu.com/s/1i64xkgP "MTI-100")