107-systems / l3xz

Home of L3X-Z, a mixed electric/hydraulic hexapod robot.

L3X-Z

This is the digital home of L3X-Z (lɛɡz), a mixed electric/hydraulic hexapod robot.

All software components are built to leverage ROS2 Humble Hawksbill.

All real-time intravehicular communication is provided via Cyphal / CAN using 107-Arduino-Cyphal.

Video

Articles

• A. Entinger (2023, January). Building a legged robot in 80 days: Lessons learned, tears shed, blood spilled.

How-to-build

cd $COLCON_WS/src
git clone https://github.com/107-systems/l3xz
cd $COLCON_WS
source /opt/ros/humble/setup.bash
colcon build --packages-select l3xz

How-to-run

L3X-Z Hexapod Robot

cd $COLCON_WS
. install/setup.bash
ros2 launch l3xz robot.py

Control Station

cd $COLCON_WS
. install/setup.bash
ros2 launch l3xz control.py

Repositories

Host Software

• l3xz_joy: ROS PS3 joystick driver for feeding l3xz_teleop node.
• l3xz_teleop: Teleoperation for L3X-Z via PS3 joystick and ROS topics.
• l3xz_mapping: L3X-Z mapping stack.

Robot Software

• l3xz_system_monitor: This packages supervises the state of all of L3X-Z ROS sub-systems.
• ros2_cyphal_bridge: Interface between ROS and L3X-Z's Cyphal connected components.
• ros2_dynamixel_bridge: Interface between ROS2 and L3X-Z's Robotis Dynamixel servos.
• l3xz_gait_ctrl: Gait controller for the L3X-Z electric/hydraulic hexapod robot.
• l3xz_head_ctrl: Head controller for the L3X-Z electric/hydraulic hexapod robot.
• l3xz_pump_ctrl: Hydraulic pump controller for the L3X-Z electric/hydraulic hexapod robot.
• l3xz_valve_ctrl: ROS package for controlling L3X-Z's valve block.
• l3xz_frontend: Web based frontend for L3X-Z.

Firmware

• l3xz-aux-ctrl-firmware: Firmware for the L3X-Z auxiliary controller (OpenCyphalPicoBase).
• l3xz-leg-ctrl-firmware: Firmware for the L3X-Z leg controller (l3xz-leg-ctrl-hardware).
• l3xz-radiation-sensor-firmware: Firmware for the L3X-Z radiation sensor (OpenCyphalPicoBase).
• l3xz-valve-ctrl-firmware: Firmware for the L3X-Z radiation sensor (OpenCyphalServoController12).
• l3xz-pressure-sensor-firmware: Firmware for the L3X-Z pressure sensor (OpenCyphalPicoBase).

Hardware

• l3xz-leg-ctrl-hardware: L3X-Z Hexapod leg controller hardware design files.
• RS485-Power-Injector: Provide battery power to RS485 devices.
• CAN-Power-Injector: Provide power via CAN to all L3X-Z CAN devices.
• PowerPole-Distributor-12: 12 - way power distribution board with Anderson PowerPole® connectors.

CAD

• l3xz-cad: L3X-Z Hexapod hardware design files (3D model, printed parts, etc.).

"Dragonbeard" pan/tilt color/thermal imaging head

• ROS: l3xz_openmv_camera: ROS driver for OpenMV camera.
• CAD: l3xz-hw-pan-tilt-head: CAD files for L3X-Z's pan/tilt color/thermal imaging head.
• Docker: l3xz-sw-pan-tilt-head: Software bundle for deployment on the Raspberry Pi Zero 2 of the pan/tilt head.

Configuration

Network Configuration ENRICH 23

Component	IP
L3X-Z Raspberry Pi 4 (Ethernet)	192.168.88.4
L3X-Z Pan/Tilt Head	192.168.88.5
L3X-Z Raspberry Pi 4 (WiFi)	192.168.88.6
L3X-Z Control PC (Ethernet)	192.168.88.9
L3X-Z Control PC (WiFi)	192.168.88.10
L01S Robot	192.168.88.101
L01S Control	192.168.88.102

• Edit /etc/network/interfaces:

auto wlan0
allow-hotplug wlan0
iface wlan0 inet static
address 192.168.88.6
netmask 255.255.255.0

• Check this script for keeping WiFi connected:

#!/bin/bash

SSID=$(/sbin/iwgetid --raw)

if [ -z "$SSID" ]
then
    echo "`date -Is` WiFi interface is down, trying to reconnect" >> /home/pi/wifi-log.txt
    sudo ifconfig wlan0 down
    sleep 30
    sudo ifconfig wlan0 up
fi

echo "WiFi check finished"

Network Configuration ELROB 22

Component	IP	Notes
MikroTik "Base Station"	192.168.88.2 (Bridge-IP)	(station bridge, nv2, pre-shared-key, l...)
MikroTik "Robot"	192.168.88.1 (Bridge-IP)	(bridge, nv2, pre-shared-key, l...)
Robot Rasperry Pi (Ethernet)	192.168.88.5
Control PC (Ethernet)	192.168.88.3
Note: MikroTik RBMetal5SHPn.

Cyphal Configuration

How-to-config via yakut

Install and configure yakut:

. setup_yakut.sh

Dump all write-able registers into cyphal-config-raw.yaml:

y rl 11,12,13,14,15,16,20,30,40,50,60 | y --yaml rb --only=mp > config/cyphal-config-raw.yaml

Format the YAML file for better human readability via pyyaml:

pip install pyyaml
python -c "import sys,yaml;yaml.dump_all(yaml.load_all(sys.stdin, yaml.Loader), sys.stdout)" < config/cyphal-config-raw.yaml | tee config/cyphal-config.yaml

Edit to file for your desired network configuration and write back:

y rb --file=config/cyphal-config.yaml

Store configuration into persistent storage and restart.

y cmd 11,12,13,14,15,16,20,30,40,50,60 store
y cmd 11,12,13,14,15,16,20,30,40,50,60 restart

l3xz-leg-ctrl-firmware

Port ID	DSDL Type	Node ID	Type	Description
1001U	uavcan::si::unit::angle::Scalar_1_0	11	Pub	Left/Front Femur Angle Actual / rad
1002U	uavcan::si::unit::angle::Scalar_1_0	11	Pub	Left/Front Tibia Angle Actual / rad
1003U	uavcan::primitive::scalar::Bit_1_0	11	Pub	Left/Front Tibia Tip Switch
1004U	uavcan::si::unit::angle::Scalar_1_0	12	Pub	Left/Middle Femur Angle Actual / rad
1005U	uavcan::si::unit::angle::Scalar_1_0	12	Pub	Left/Middle Tibia Angle Actual / rad
1006U	uavcan::primitive::scalar::Bit_1_0	12	Pub	Left/Middle Tibia Tip Switch
1007U	uavcan::si::unit::angle::Scalar_1_0	13	Pub	Left/Back Femur Angle Actual / rad
1008U	uavcan::si::unit::angle::Scalar_1_0	13	Pub	Left/Back Tibia Angle Actual / rad
1009U	uavcan::primitive::scalar::Bit_1_0	13	Pub	Left/Back Tibia Tip Switch
1010U	uavcan::si::unit::angle::Scalar_1_0	14	Pub	Right/Back Femur Angle Actual / rad
1011U	uavcan::si::unit::angle::Scalar_1_0	14	Pub	Right/Back Tibia Angle Actual / rad
1012U	uavcan::primitive::scalar::Bit_1_0	14	Pub	Right/Back Tibia Tip Switch
1013U	uavcan::si::unit::angle::Scalar_1_0	15	Pub	Right/Middle Femur Angle Actual / rad
1014U	uavcan::si::unit::angle::Scalar_1_0	15	Pub	Right/Middle Tibia Angle Actual / rad
1015U	uavcan::primitive::scalar::Bit_1_0	15	Pub	Right/Middle Tibia Tip Switch
1016U	uavcan::si::unit::angle::Scalar_1_0	16	Pub	Right/Front Femur Angle Actual / rad
1017U	uavcan::si::unit::angle::Scalar_1_0	16	Pub	Right/Front Tibia Angle Actual / rad
1018U	uavcan::primitive::scalar::Bit_1_0	15	Pub	Right/Front Tibia Tip Switch

l3xz-aux-ctrl-firmware

Port ID	DSDL Type	Node ID	Type	Description
2001U	uavcan::primitive::scalar::Bit_1_0	20	Pub	Emergency Stop
2002U	uavcan::primitive::scalar::Integer8_1_0	20	Sub	Light Mode

l3xz-radiation-sensor-firmware

Port ID	DSDL Type	Node ID	Type	Description
3001U	uavcan::primitive::scalar::Natural16_1_0	30	Pub	Radiation Tick Count

l3xz-valve-ctrl-firmware

Port ID	DSDL Type	Node ID	Type	Description
4001U	uavcan::primitive::array::Natural16_1_0	40	Sub	Servo Pulse Width / us

Zubax Robotics Orel 20

Port ID	DSDL Type	Node ID	Type	Description
5001U	reg::udral::service::common::Readiness_0_1	50	Sub	Readiness
5002U	reg::udral::service::actuator::common::sp::Scalar_0_1	50	Sub	RPM Setpoint

l3xz-pressure-sensor-firmware

Port ID	DSDL Type	Node ID	Type	Description
6001U	uavcan::si::unit::pressure::Scalar_1_0	60	Pub	Hydraulic Circuit #0 Pressure
6002U	uavcan::si::unit::pressure::Scalar_1_0	60	Pub	Hydraulic Circuit #1 Pressure

l3xz's Issues

[Feature Request] Remove automatic launch of L3XZ cameras from this ROS node.

⚡ Feature Request

Instead of starting the L3XZ OpenMV cameras within this node the launch shall happen within the robot-local launch file.