okvis_cg

okvis ros wrapper and the core code is the modified version of okvis-1.1.3

OKVIS(Open Keyframe-based Visual-Inertial SLAM) tracks the motion of an assembly of an Inertial Measurement Unit (IMU) plus N cameras (tested: mono, stereo and four-camera setup) and reconstructs the scene sparsely. This is the Author’s implementation of the [1] and [3] with more results in [2]. There is currently no loop-closure detection / optimisation included, but we are working on it.

Code

• ethz-asl/okvis (Github)
• ethz-asl/okvis_ros (Github)

Doc

• https://ethz-asl.github.io/okvis/

Papers

• [1] Stefan Leutenegger, Simon Lynen, Michael Bosse, Roland Siegwart and Paul Timothy Furgale. Keyframe-based visual–inertial odometry using nonlinear optimization. The International Journal of Robotics Research, 2015.
• [2] Stefan Leutenegger. Unmanned Solar Airplanes: Design and Algorithms for Efficient and Robust Autonomous Operation. Doctoral dissertation, 2014.
• [3] Stefan Leutenegger, Paul Timothy Furgale, Vincent Rabaud, Margarita Chli, Kurt Konolige, Roland Siegwart. Keyframe-Based Visual-Inertial SLAM using Nonlinear Optimization. In Proceedings of Robotics: Science and Systems, 2013.

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Build

• okvis

  cd okvis
  mkdir build & cd build
  cmake .. & make -j4

• okvis_ros

  mkdir -p ws_okvis/src
  cd ws_okvis/src
  git clone xxx
  cd ..
  catkin_make -j3

Run

without ROS

• MH_01_easy Dataset

  ./okvis_app_synchronous \
      path/to/okvis/config/config_fpga_p2_euroc.yaml \
      path/to/MH_01_easy/mav0/

  or

  cd okvis & bash run_with_mav0.sh

with ROS

• MH_01_easy Dataset:

  rosrun okvis_ros okvis_node_synchronous \
      path/to/okvis_ros/okvis/config/config_fpga_p2_euroc.yaml \
      path/to/MH_01_easy.bag

  or

  roslaunch okvis_ros okvis_node_synchronous.launch rviz:=true [mono:=true] bag:=<bag-file-path>

• MYNTEYE-S1030 (Stereo + IMU)

  roslaunch okvis_ros okvis_node_mynteye.launch rviz:=true

results

• run with MH_01_easy dataset (without ROS)

• run with MH_01_easy dataset (with ROS)

• run with MYNTEYE-S1030 (Stereo+IMU, with ROS)

Supported Camera and Distortion models

• pinhole camera model (pinhole) [fu fv pu pv]
  • equidistant [k1 k2 k3 k4]
  • radialtangential (plumb_bob) [k1 k2 r1 r2]
  • radialtangential8 (plumb_bob8)
  • none

Outputs and frames

In terms of coordinate frames and notation,

• W denotes the OKVIS World frame (z up),
• C_i denotes the i-th camera frame
• S denotes the IMU sensor frame
• B denotes a (user-specified) body frame.

The output of the okvis library is the pose T_WS as a position r_WS and quaternion q_WS, followed by the velocity in World frame v_W and gyro biases (b_g) as well as accelerometer biases (b_a).

HEALTH WARNING

If you would like to run the software/library on your own hardware setup, be aware that good results (or results at all) may only be obtained with appropriate calibration of the

• camera intrinsics,
• camera extrinsics (poses relative to the IMU),
• knowledge about the IMU noise parameters,
• and ACCURATE TIME SYNCHRONISATION OF ALL SENSORS.