用evo工具评估SLAM轨迹

转载：https://blog.csdn.net/A_L_A_N/article/details/88708979

evo github 地址：https://github.com/MichaelGrupp/evo

不同格式的轨迹文件及相互转换：https://github.com/MichaelGrupp/evo/wiki/Formats

问题汇总：https://github.com/MichaelGrupp/evo/issues?q=is%3Aissue+is%3Aclosed

1、安装 evo

1. sudo apt install python-pip

2. pip install evo --upgrade --no-binary evo

出现问题： 

1. Could not install packages due to an EnvironmentError: [Errno 13] Permission denied: '/usr/lib/python2.7/dist-packages/dateutil/relativedelta.pyc'

2. Consider using the `--user` option or check the permissions.

解决：

pip install evo --upgrade --no-binary evo --user

2、测试

1. cd ~/alan_dataset/EuRoC/mav0/state_groundtruth_estimate0

2. evo_traj euroc data.csv --plot

出现问题：

1. name: data

2. infos: 19753 poses, 91.747m path length, 98.760s duration

3. /usr/lib/python2.7/dist-packages/matplotlib/font_manager.py:273: UserWarning: Matplotlib is building the font cache using fc-list. This may take a moment.

4. warnings.warn('Matplotlib is building the font cache using fc-list. This may take a moment.')

5. [ERROR] Unhandled error in evo.main_traj

6. Traceback (most recent call last):

7. File "/home/jinshan.lan/.local/lib/python2.7/site-packages/evo/entry_points.py", line 90, in launch

8. main_module.run(args)

9. File "/home/jinshan.lan/.local/lib/python2.7/site-packages/evo/main_traj.py", line 342, in run

10. from evo.tools.plot import PlotMode

11. File "/home/jinshan.lan/.local/lib/python2.7/site-packages/evo/tools/plot.py", line 36, in <module>

12. import mpl_toolkits.mplot3d.art3d as art3d

13. File "/usr/lib/python2.7/dist-packages/mpl_toolkits/__init__.py", line 2, in <module>

14. __import__('pkg_resources').declare_namespace(__name__)

15. File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 2927, in <module>

16. @_call_aside

17. File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 2913, in _call_aside

18. f(*args, **kwargs)

19. File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 2940, in _initialize_master_working_set

20. working_set = WorkingSet._build_master()

21. File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 637, in _build_master

22. return cls._build_from_requirements(__requires__)

23. File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 650, in _build_from_requirements

24. dists = ws.resolve(reqs, Environment())

25. File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 834, in resolve

26. raise VersionConflict(dist, req).with_context(dependent_req)

27. ContextualVersionConflict: (numpy 1.11.0 (/usr/lib/python2.7/dist-packages), Requirement.parse('numpy>=1.12.0'), set(['pandas']))

28.  

29. [ERROR] evo module evo.main_traj crashed - no logfile written (disabled)

解决：

pip install numpy --upgrade --user

运行结果：

3、将 EuRoC 数据集中 .csv 文件形式的 groundtruth 转换为 TUM 形式的轨迹文件

evo_traj euroc data.csv --save_as_tum

TUM 形式的轨迹文件格式：

每行8个数，用空格分隔，包含时间戳（单位：秒）、位置和旋转（四元素表示）

timestamp x y z q_x q_y q_z q_w

4、多轨迹显示（轨迹未对齐）

（a）上面将 EuRoC 数据集中 MH_04_difficult 序列的 groundtruth(.csv文件) 转换为 TUM 形式的轨迹文件，文件名为 data.tum

（b）通过双目 ORBSLAM 跑 MH_04_difficult 数据集得到 TUM 形式的轨迹文件，文件名为 FrameTrajectory_TUM_Format.txt

见：ORB_SLAM2 & VI-ORBSLAM 相关（#alan#）

将两个 TUM 形式的轨迹文件放入同一个文件夹 (test_evo) 中

1. cd ~/Desktop/test_evo

2. evo_traj tum FrameTrajectory_TUM_Format.txt --ref=data.tum -p

运行结果：

 

5、计算绝对位姿误差（轨迹对齐）

evo_ape tum data.tum FrameTrajectory_TUM_Format.txt -va --plot

运行结果：

    

绝对轨迹误差：APE（Absolute Trajectory Error）

gt（groundtruth）为真实轨迹;est(estimate):估计轨迹

绝对轨迹的误差为每个位姿李代数的均方根误差（Root-Mean-Squared Error,RMSE）

绝对平移误差（Average Translational Error）

trans括号表示内部变量的平移部分。

参考：

知乎：一种评估SLAM系统参数的实用工具

使用 evo 工具评测 VI ORB SLAM2 在 EuRoC 上的结果

视觉SLAM十四讲第二版