Visual Inertial SLAM

Implementation of Monocular Simultaneous Localization and Mapping (SLAM) using inertial sensors. This implementation used OpenCV 3.2 and ROS Kinect.

VI-SLAM is a free and open source licensed under the GPL-3.0 License.

Table of Contents

• Requirements
• Getting Started
• Directory Layout
• License

Requirements

• OpenCV 3.2 and extra modules.
• ROS Kinetic.

Getting Started

From a fresh Ubuntu 16.04 LTS, install the following dependencies:

OpenCV 3.2

Refer to OpenCV.

ROS Kinetic

Refer to ROS Kinetic installation instructions.

Building VI-SLAM

Clone VI-SLAM repository in the /src folder of your catkin workspace:

cd <catkin_ws_directory>/src
git clone https://github.com/MecatronicaUSB/vi-slam.git
cd ..
catkin_make

Usage

General datasets

Run VI-SLAM on a dataset of images with known camera calibration parameters and image dimensions and sampling rate of camera and IMU.

Modify the calibration.xml file in /calibration folder to specify the instrinsic parameters of the camera of the dataset to use.

    -d <directory of images files>                  
    -c <directory of calibration.xml file>          (<vi-slam directory>/calibration/calibration.xml)
    -s <number of starting frame>                   (Default: 0)

Modify the vi_slam.launch file in /launch folder to specify the directory of files
(Refer to /calibration/calibrationEUROC.xml for proper configuration of the .xml file).

    <!-- Images dimensions (Input) -->
    <in_width  type_id="integer"> W </in_width>       (Input dimentions of images)
    <in_height type_id="integer"> H </in_height>      (Replace W: width, H: height)

    <!-- Images dimensions (Output) -->
    <out_width  type_id="integer"> W </out_width>     (Output desired dimentions of images)
    <out_height type_id="integer"> H </out_height>    (Replace W: width, H: height)

    <!-- Calibration Values of Dataset -->
    <calibration_values type_id="opencv-matrix">      (Intrinsic camera parameters)
    <rows>1</rows>                                    (Replace fx fy cx cy)
    <cols>4</cols>
    <dt>f</dt>
    <data>
        fx  fy  cx  cy </data></calibration_values> 

    <!-- Distortion coefficients -->
    <rectification type_id="opencv-matrix">          (Distortion parameters, optional)
    <rows>1</rows>                                   (Replace k1 k2 k3 k4)
    <cols>4</cols>                                   (If not: 0  0  0  1)
    <dt>f</dt>  
    <data>
        k1  k2  k3  k4 </data></rectification>

Run VI-SLAM for general datasets:

roslaunch vi_slam vi_slam.launch

EUROC dataset

Currently, VI-SLAM supports ground-truth visualization along with VI-SLAM results for EUROC MAV datasets. For these datasets, corresponding calbration.xml files are located in the /calibration folder.

EUROC

For EUROC MAV datasets, modify the arguments of the vi_slamEUROC.launch file in /launch folder to add the directory of the files.

    -d <directory of images files>                  (<EUROC directory>/mav0/cam0/data/)
    -c <directory of calibrationEUROC.xml file>     (<vi-slam directory>/calibration/calibrationEUROC.xml)
    -s <number of starting frame>                   (Default: 0)
    --EUROC <directory of ground-truth poses file>  (<EUROC directory>/mav0/vic0/data.csv)

Run VI-SLAM for EUROC datasets:

roslaunch vi_slamvi_slamEUROC.launch

Software Details

• Implementation done in C++.
• Using Rviz as visualization tool.

Directory Layout

/src

Core .cpp files of VI-SLAM.

/include

Libraries .h files of VI-SLAM.

/launch

VI-SLAM launch files for easy ROS Kinetic execution.

/calibration

Calibration files. Includes calibration for EUROC datasets. It can be modified for local datasets.

License

Copyright (c) 2019 Luis Lujano ([email protected]).

Release under the GPL-3.0 License.