cptl_ros

ROS driver to manage and publish Signal Phase and Timing (SPaT) information on single Connected Portable Traffic Light (CPTL) system in CAVAS ecosystem.

The cptl_ros package has been tested under ROS Kinethic and Melodic on Ubuntu 16.04, Ubuntu 18.04 and Raspberry Pi 64bit OS. The driver is compatible with Jetson Nano and Raspberry Pi 4B hardware.

Latest releases:

Driver version	CAVAS_ecosystem supported	CPTL hw/sw supported
v1.1	v1.0 or newer	V2.1 or newer
v1.0	v1.0 or newer	V2.1 or newer

WARNING: GPIO output pins are device/protocol specific and must be verified or modified according to the hardware in-use. This driver requires BCM2835-compatible processor to run properly.

Dependencies

• Broadcom BCM2835 v1.60 library (link)
• ROS Kinetic (link) or Melodic (link)
• cavas_msgs (link)
• std_msgs (link)

Installation and Configuration

Install BCM2835 v1.60 C library or visit https://www.airspayce.com/mikem/bcm2835/ for latest version:

mkdir ~/BCM2835 && cd ~/BCM2835
wget http://www.airspayce.com/mikem/bcm2835/bcm2835-1.60.tar.gz
tar zxvf bcm2835-1.60.tar.gz 
cd bcm2835-1.60/
sudo ./configure
sudo make && sudo make check && sudo make install

The infrastructure will publish SPaT information in the form of cavas_msgs::SPaT. The package cavas_msgs contains all the messages required accross CAVAS ecosystem. To install cavas_msgs, simply clone and install cavas_ecosystem core package:

source /opt/ros/$ROS_DISTRO/setup.bash
cd ~/catkin_ws/src
git clone https://github.com/zlg9folira/CAVAS_ecosystem.git && cd ..
catkin_make --only-pkg-with-deps cavas_ecosystem

Finally, download and install cptl_ros driver:

cd ~/catkin_ws/src
git clone https://github.com/zlg9folira/cptl_ros.git && cd ..
catkin_make --only-pkg-with-deps cptl_ros

Usage

To launch the driver, simply run the following command on the CPTL infrastructure:

roslaunch cptl_ros cptl_3phase.launch

User-defined parameters

• id_: The unique ID of the infrastructure (default 0)
• total_phase_number_: Number of signal phases supported by traffic light (default 3)
• infra_class_: Target signal class of the infrastructure, e.g., pedestrian', 'vehicle (default vehicle)
• duration_red_: Timing in seconds for red signal (default 10)
• duration_amber_: Timing in seconds for amber (yellow) signal (default 4)
• duration_green_: Timing in seconds for green signal (default 10)
• gpio_out_red_: Pin number connected to red signal relay switch (default 16)
• gpio_out_amber_: Pin number connected to amber (yellow) signal relay switch (default 14)
• gpio_out_green_: Pin number connected to green signal relay switch (default 12)
• infra_latitude_: Latitude coordinate of the infrastructure (default 0.0)
• infra_longitude_: Longitude coordinate of the infrastructure (default 0.0)
• run_for_ever_: Flag variable to set for infinit cycle count for SPaT (default true)
• topic_prefix_: Naming convention for SPaT ROS topic prefix (default /infra/cptl_)
• frame_: Naming convention for SPaT ROS topic frame ID (default cptl)

Note: ROS topic naming convention follows the given infrastructure ID. It means that if id_ is set to 0, then SPaT messages will be published on /infra/cptl_0 topic.

Advertised Topic(s)

• /infra/cptl_0 (cavas_msgs/SPaT) containing global position, current phase, next phase, time to next phase, etc., for particular CPTL system.

Meta

Credit:

Foad Hajiaghajani - UB CAVAS