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

Requirements

• VOXL or VOXL-Flight with VOXL System Image 2.3.0 or newer
• VOXL ToF Sensor (available here)
• Linux with Rviz
• Setup ROS on Host PC
• Setup ROS on VOXL

Hardware

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

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
  • In RViz choose Fixed Frame toption as /base_link instead of map
  • Open your .rviz file (by default in /home/xxx/.rviz/default.rviz)

vi /home/xxx/.rviz/default.rviz

• Change the “Fixed Frame:” option from “map” to “base_link”
  • Global Options: Fixed Frame: /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:

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”