Author(s): Christopher Chan

Overview

EGM stands for ephemeral grid mapping (I will try to come up with better names next time). EGM_class is the name of the package, and the name of the class used as the nodelet. EGM_ns is the name of the C++ namespace used for the project. This nodelet subscribes to a lidar point cloud, stereo point cloud and a sonar polygon message and outputs the a set of polygons that will be processed by the virtual bumper node. Full report describing code and findings is available at:

https://docs.google.com/document/d/1T3X65S8JkSBpmvoSFQGFBKfZ1-tISEBzRHocDmxHMqA/edit?usp=sharing.

Demo of this code is available at:

https://www.youtube.com/watch?v=K7GaomP2tZw

Subscribed Topics

• /lidar (sensor_msgs::PointCloud2)

  Lidar pointcloud from Velodyne.

• /stereo (sensor_msgs::PointCloud2)

  Realsesne pointcloud.

• /sonar (zio_obstacle_msgs/ObstaclesStamped)

  Obstacle polygons from sonar array.

Published Topics

• /obstacles (zio_obstacle_msgs/ObstaclesStamped)

  A set of obstacle polygons to be processed by the virtual bumper node.

• /grid_map_fused (grid_map_msgs/GridMap)

  For visualizing grid cells that were determined to be obstacles.

Parameters

The full list of parameters that can be tuned is listed in EGM_bumper/config/param.default.yaml.

Install dependencies

$ sudo apt-get install ros-kinetic-grid-map

$ cd your_workspace/src
$ git clone https://gitlab.acfr.usyd.edu.au/zio/zio_obstacle.git
$ catkin build virtual_bumper
$ catkin build zio_obstacle_msgs

To Build

$ cd your_workspace/src
$ git clone https://gitlab.acfr.usyd.edu.au/c.chan/egm_bumper.git
$ catkin build EGM_class --cmake-args -DCMAKE_BUILD_TYPE=Release

To Run (on local machine)

Download a bag listed in egm.launch from RCOS and change the default path in egm.launch.

Terminal 1:

$ export PLATFORM_NAME=zio-003
$ roslaunch zio_description zio_description.launch 

Terminal 2:

$ roslaunch EGM_class egm.launch 

To Run Testing with Gamepad (on EV)

Connect gamepad to EV and go into gamepad mode on EV.

$ sudo systemctl start zio-gamepad-teleop.service

Connect ethernet from laptop to EV. Change ROS master and launch EGM bumper on your laptop (don't forget to source your workspace).

$ export ROS_MASTER_URI=http://zio-nuc:11311  
$ roslaunch EGM_class egm.launch bag_play:=false

Run the following commands in another terminal on your laptop (don't forget to source your workspace). Make sure you change virtual_bumper.yaml according to your needs.

$ export ROS_MASTER_URI=http://zio-nuc:11311 
$ cd (Path to EGM_bumper)/scripts
$ rosparam delete zio/virtual_bumper
$ rosparam load virtual_bumper.yaml zio/virtual_bumper
$ rostopic pub -1 zio/virtual_bumper/reload_parameters std_msgs/Empty '{}'

Bugs and Other Probelms

Let me know if there's anything that was unclear or if there are some bugs that need to be changed.