time_stamper

This project is currently in development

Timestamping

• Clock frequency: 1 - 10'526'315 hz ~95 nanoseconds
• Every 640 cycles a Timestamp is generated (64 * 10)
• If clock is e.g. 10 hz, it takes 64s to generate a timestamp.

Packages

Package	Installed on	Description
kernel module	Raspberry Pi CM4	Used for hardware timestamping. See kernel module
time_stamper_ros	Raspberry Pi CM4	Used for led control and timestamp generation.
time_stamper_cv	Host	Used to detect real time led state with OpenCV.

Installation

Prerequisites

• Host PC and Raspberry Pi Compute Module 4 with ROS installed.
• Requires custom TimeStamper board with CM4 mounted.
• ROS Camera driver
• Works with ROS Melodic and newer

Raspberry Pi CM4 installation

• Go to catkin workspace cd catkin_ws/src
• Clone this repo with git clone https://github.com/ethz-asl/time_stamper
• Setup, compile and start the kernel module
• catkin build time_stamper_ros
• Start ROS node with roslaunch time_stamper_ros time_stamper_default.launch
• Optional: time_stamper_cv can be removed

Host installation

• Go to catkin workspace cd catkin_ws/src
• Clone this repo with git clone https://github.com/ethz-asl/time_stamper
• Build with catkin build time_stamper_cv
• Source ros env with source ~/catkin_ws/devel/setup.bash
• Start ROS Node with roslaunch time_stamper_cv time_stamper_cv.launch
• Optional: The kernel module and time_stamper_ros can be removed