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VOXL ToF Sensor User Guide

Table of contents

  1. Requirements
  2. Hardware
  3. Guide
    1. Connect to VOXL Over Wi-Fi
    2. Start roscore on VOXL
    3. Conifugre Cameras on VOXL
    4. Configure ROS On Desktop
    5. Launch ToF Node on VOXL
    6. Launch RViz on Desktop

VOXL ToF

Requirements

Hardware

  • Ensure VOXL/VOXL-Flight is powered off
  • Connect to VOXL/VOXL-Flight connector J3 as shown

VOXL ToF Install

Guide

Below describes a method to quickly validate the hardware connections and system.

Connect to VOXL Over Wi-Fi

  • Setup and connect VOXL/VOXL-Flight as an access point
  • SSH onto the target:
ssh root@192.168.8.1
oelinux123

Start roscore on VOXL

On VOXL:

# view network information
ifconfig
  • This will give you the IP address of the VOXL, configure ROS with this:
export ROS_IP=IP-ADDR-OF-VOXL
source /opt/ros/indigo/setup.bash
roscore &
  • This will print a line that should read something like this: ROS_MASTER_URI=http://AAA.BBB.CCC.DDD:XYZUV/
    • Note: The HTTP address will be different

Conifugre Cameras on VOXL

On VOXL:

  • Ensure the environment variables are setup by runnin the following commands:
bash
setprop persist.camera.modalai.tof 1
voxl-configure-cameras
  • Select the option that best fits your setup, For camera-id please check here
    • Note: for standalone testing, you can select option 5 tof + tracking
  • Update environment:
exec bash

Configure ROS On Desktop

On Linux desktop:

  • Find IP address
# view network information
ifconfig
  • Configure ROS environment variables, where the ROS_MASTER_URI is what you saw on the VOXL when you ran roscore & in the above step
export ROS_IP=IP-ADDR-OF-PC
export ROS_MASTER_URI=http://AAA.BBB.CCC.DDD:XYZUV/
  • source variables, where xxxxxx is the ROS version you have installed
source /opt/ros/xxxxx/setup.bash

The 2 transforms (for both laser scan and point cloud) are in the tof.launch file

  • Open your .rviz file (by default in /home/xxx/.rviz/default.rviz or /opt/ros/xxx/share/rviz/default.rviz)
vi /home/xxx/.rviz/default.rviz

or 

vi /opt/ros/xxx/share/rviz/default.rviz
  • Locate a “Global Options:” node
  • Change the “Fixed Frame:” field from “/map” to “/base_link”

Launch ToF Node on VOXL

roslaunch /opt/ros/indigo/share/voxl_hal3_tof_cam_ros/launch/tof.launch
  • Ensure the ROS node launches OK:

ToF Node

Launch RViz on Desktop

  • On the host computer, run RViz
rviz
  • On the leftmost column click on the “Add” button
  • In the pop-up options click on “Image”
  • Change Display Name to “IR-Image”
  • In the left column under “IR-Image” tab select type in Image Topic as /voxl_ir_image_raw
  • Click on the “Add” button again
  • In the pop-up options click on “Image”
  • Change Display Name to “Depth-Image”
  • In the left column under “Depth-Image” tab select type in Image Topic as /voxl_depth_image_raw
  • “Add” PointCloud2 with Topic as “/voxl_point_cloud”
  • “Add” LaserScan with Topic as “/voxl_laser_scan”

ToF Visualized