OmniVeyors

Root Repository for the OmniVeyor Robots.

Robot configuration

Hardware Setup

• Remove top panel and rear panel.
• Remove UPS and short the two pairs of wires with two connection blocks (+ with +, - with -)
• Install SSD and PCI-e to USB 3.0 card inside the robot computer. Remove the dedicated graphics card to make room for the USB 3.0 card.
• Install Hokuyo UST-10LX LiDAR, Power the LiDAR from terminals (+12V and GND).
• Install Arduino and custom function button. Button connects to Pin D8 and GND. LED on the button (5V) connects to D11 and GND.
• Install wireless charger. The receiver side of the charger has two power lines and three signal lines. Connect Power Red to Battery + (red), Power Black to Battery - (black). Connect Signal Brown (Control) to Arduino D12, Signal Yellow (Fault) to Arduino D13, and Signal Blue (GND) to Arduino GND.
• Check and set servo motor IDs. Front Right Steer - 1, Front Right Roll - 2, Front Left Steer - 3, Front Left Roll - 4, ..., Rear Right Roll - 8.
• Install RealSense Cameras. Front Left: D435i. Front Right: T265. Rear Right: D435i (optional). Connect the USB cables to the USB 3.0 card. From left to right the order is: T265, No Connection, Rear D435i, Front D435i.

Install Linux System

Recommended: Lubuntu 20.04 or Kubuntu 20.04.

LXQt / KDE + SDDM uses significantly less RAM and CPU resources than the default Gnome desktop in Ubuntu 20.04.

Specific to the ADLink MXC6300 machine on the robot

• Pre-installation: Hold Del key to enter BIOS. Find Advanced > Advanced Power Management > Restore AC Power Loss. Set to Power On.

• Find Chipset > Primary IGFX Boot Display. Set to DP1. Then find Active LFP and set to Int-LVDS. Set the LCD Panel Type to the desired resolution resolution (1920x1080 LVDS for example). This option creates a virtual screen for graphical display when the robot is running headless.

• Insert installation media. Press F4 key to Save and Reset.

• Installation: Hold Del to enter BIOS. In the Save and Exit tab, find the installation media and override boot order.

• Enter live session and install system. In case the virtual screen is recognized as the main screen and you see a blank desktop, use the following key order to invoke monitor setting: Windows, m, o, n, up, Enter In the opened window select Unified View.

Setup Linux System

• This section assumes you have already installed Lubuntu 20.04, or equivalent flavors with SDDM desktop manager.
• Clone this repository to ~/Dev, for example:

  mkdir -p ~/Dev/ros_ws/src
  cd ~/Dev/ros_ws/src
  git clone https://github.com/HaoguangYang/omniveyor.git

• In the ros_ws folder, run the all-in-one setup script:

  cd ..; ./src/omniveyor/systemInitialSetup.sh

• Sit back and relax!

File Structure

ros_ws/src/
      |---omniveyor <This repository>
      |   |---omniveyor_mobility (High-level package for mapping, localization, and navigation)
      |   |---spatio_temporal_voxel_layer (MoveBase plugin for spatio voxel cloud generation and obstacle avoidance)
      |   ----nimbro_network (Multi ROS master communication infrastructure)
      |---omniveyor_common (Common definitions, message types, and definitions across hardware and simulator)
      |---omniveyor_hardware
      |   |---pcv_base (Robot base driver)
      |   |---<Placeholder for future hardware>
      |   ----robot_localization (Odometer filtering tools -- EKF, UKF, etc.)
      ----omniveyor_simulator
          |---omniveyor_gazebo_world (Robot simulator main)
          ----realsense_ros_gazebo (Plugin for Realsense simulation)

Debugging and Troubleshooting

• To debug CAN bus, use candump:

  candump -ax can0

  The documentation for the iPOS motor controller CAN protocol can be found HERE.

• If canbus keeps dropping frames, may need to manually address QoS strategy in /etc/systemd/system/canbus.service:

  # change congestion control method for CAN0 to ensure data packets are not stale under congestion.
  ExecStartPre=... && tc qdisc add dev can0 root handle 1: pfifo_head_drop limit 9

• If you are using Gnome desktop manager, comment out the x11vnc section of the ./systemInitialSetup.sh script, and use the inbuilt Vino server instead. The VNC server is started through Settings > Sharing > Desktop Sharing. Optional enable access of VNC through Windows machines by turning off encryption (NO sudo):

  gsettings set org.gnome.Vino require-encryption false

• If WiFi dongle works below expectation, first make sure it is plugged into a USB2 port instead of a USB3 port. USB3 is known for its excessive interference within the 2.4GHz frequency range. If the port switching still does not solve the issue, you may try to use third-party driver, e.g. Aircrack-ng's RTL 8188EUS driver for better WiFi connection.

• qterminal may be swapped by xterm in some occasions during the installation of ros-noetic-fkie-multimaster. If you feel uncomfortable, do:

  sudo mv /usr/bin/xterm /usr/bin/xterm.old && sudo ln -s /usr/bin/qterminal /usr/bin/xterm

• Deprecated, Use with Caution This repository includes a bootup script, such that the SSH and VNC ports of the cart are mapped to a Virtual Private Server with static IP. To enable the automatic bootup sequence, add the following line in crontab -e:

  @reboot sleep 30; cd /home/cartman/Dev/Mobile_Manipulation_Dev/; sh ./onBoot.sh

  WARNING: The program will run 30s after the machine is booted up. Plugging in a joystick will mobilize the robot. Refer to autorun.py (under src/pcv_base/scripts) for series of commands it executes.

Compile and run the code:

catkin_make -DCMAKE_BUILD_TYPE=Release

Then run the launch files in pcv_base and omniveyor_mobility packages.

Deprecated Automatic run procedure is defined in the autorun.py, which structures a move of the robot as a "task", as defined in the pcv_base/scripts folder:

autorun.py --(imports)--> task --(imports)--> payload
                            |----(calls)--> launch
                            |----(uses)--> resources

Base Station configuration

A base station is the computer that wirelessly connects to all active robots, issuing commands to the robots and monitoring their status. Two approaches of interconnecting multiple robots are provided -- through native ROS setup, and through the nimbro_network package.

Connect to the robot with Remote ROS Master

export ROS_MASTER_URI=http://$ROBOT_IP:11311
export ROS_IP=$(ip route get 1 | awk '{print $(NF-2);exit}')

If rostopic list works but no message comes through, check:

• Router is resolving local hostnames (try ping $ROBOT_HOSTNAME.local to verify $ROBOT_HOSTNAME.local is reachable).
• ROS_IP or ROS_HOSTNAME setting on the robot side. Refer to ROS Network Setup.

Connect to the robot with nimbro_network

On the base station side:

roslaunch omniveyor_mobility multi_robot_p2p_onHost.launch

On the robot side:

roslaunch pcv_base multi_robot_p2p.launch

Multi-Robot Working Example:

Network setup

Host, Robot 1, Robot 2, and Robot 3 are all connected to the same WiFi Access Point. Assume the IP addresses of the robots and hosts are under 192.168.254.96/26, with the robot addresses start from 192.168.254.101.

Operation Procedures

N.B. Replace 192.168.254.10X with actual node IP

1. Power up robots

For new setup:

2. ssh into one of the robot: ssh [email protected]

3. on robot: cd Dev/omniveyor_newsetup && source devel/setup.bash

4. on robot: roslaunch omniveyor_mobility build_map.launch map_save_period:=30

5. on host: Connect the joystick and then cd omniveyor_ws && source devel/setup.bash

6. on host: roslaunch omniveyor_mobility remote_teleop_on_host.launch node_id:=X

7. on host (optional for visualization): source devel/setup.bash && export ROS_MASTER_URI=http://192.168.254.10X:11311 && export ROS_IP=$(ip route get 1 | awk '{print $(NF-2);exit}') && roslaunch omniveyor_mobility visualization.launch

8. on robot: to enable motors rostopic pub -1 /control_mode std_msgs/Byte "data: 1"

   on host: teleop the robot with joystick until test area is covered. Exit launch file started in step 4;

   on robot: to disable motors rostopic pub -1 /control_mode std_msgs/Byte "data: 0"

9. copy folder on robot omniveyor_newsetup/src/omniveyor/omniveyor_mobility/resources/maps/ to peer robots. Use sftp [email protected] and then put -R / get -R the maps folder

For each robot, place robot at mapping origin:

10. ssh into robots: ssh [email protected]

11. on robot: cd Dev/omniveyor_newsetup && source devel/setup.bash

12. on robot: roslaunch omniveyor_mobility robot_remote_teleop_pos_feedback.launch

13. on host: Connect the joystick and then cd omniveyor_ws && source devel/setup.bash

14. on host: roslaunch omniveyor_mobility multi_robot_remote_teleop_on_host.launch

    Then, follow instructions on the terminal to enable robots and drive individual robots (Modes 0...2) until positioning covariance converges.

15. on host (optional for visualization): source devel/setup.bash && export ROS_MASTER_URI=http://192.168.254.10X:11311 && export ROS_IP=$(ip route get 1 | awk '{print $(NF-2);exit}') && roslaunch omniveyor_mobility visualization.launch

16. Enter Mode 3 and drive three robots simultaneously in formation.

Cleanup:

18. on robot: Ctrl + C on all three robots

Simulator Configuration

A gazebo-based simulator is included in the meta-package. Please refer to the README of OmniVeyor_Gazebo_World repository.