Architecture

Deadeye consists of software and hardware that together provide a vision processing system for FRC robots. The main system components are identified in the block diagram below. In addition to the main vision processing pipeline shown in red, we have an adminstration dashboard in blue, and miscellaneous services in yellow.

Although typically used on a Jetson Nano Developer Kit, the Deadeye server software (vision process daemon and admin dashboard web server) can be installed on any Linux system with the appropriate C++ compiler and development libararies installed.

Software

The Deadeye system has several components that run on a vision coprocessor, client roboRIO and web browser. They communicate over the network and require a running NetworkTables server.

Camera Pipeline Daemon

The main vision processing process running on the vision coprocessor that manages up to five cameras and associated target processing pipelines. Each running instance is identified by a unit ID: A, B, C...

Communication is via NetworkTables for configuration and control via the web admin dashboard server and the Java client library and via UDP for streaming targeting data to the Java client library. It also provides an on-demand camera video stream directly to the web admin dashboard client over TCP.

It runs as a systemd service named deadeye-daemon.service.

Java Client Library

A Java client libary (javadocs) used by FRC roboRIO robot code to control and communicate with the camera pipeline daemon running on the vision co-processor. Communication to other components is via NetworkTables for configuration and control and to the camera pipeline daemon directly via UDP for streaming target data.

See the Quickstart for installation and usage instructions.

Web Admin Dashboard Server

A Python web service running on the Nano that is the backend for the web admin dashboard client, that configures and controls the camera pipeline daemon.

Communication with the camera pipeline daemon is via NetworkTables and with the web admin dashboard client via a websocket using the Socket.IO protocol.

It runs as a systemd service named deadeye-admin.service.

Web Admin Dashboard Client

The web-based adminstration dashboard run on a developer's computer used to control, configure and monitor the camera pipeline daemon.

It communicates with the web admin dashboard server over websockets and streams camera preview video directly from the camera pipeline daemon over TCP as MJPEG.

It can be loaded by connecting with a web browser to port 5000, for example, http://10.27.67.10:5000/.

Shutdown Service

A background service running on the Nano that watches for a shutdown button press and performs a clean shutdown if it pressed for three or more seconds.

It runs as a systemd service named deadeye-shutdown.service.

Hardware

Deadeye software is designed to interact with cameras, lights and a shutdown switch attached to the Jetson Nano.

Camera

Any camera(s) supported by the Nano can be used. Deadeye supports up to five attached cameras per unit. Our default camera is a Raspberry Pi Camera Module V2 connected to the J13 camera connector.

Lights

Our default vision processing pipeline relies on bright green LED illumination reflected by retro-reflective target tape back to the camera.

We drive the green LEDs using a LUXdrive A009-D-V-1000 BuckBlock LED driver module.

Each camera can have its own light driver circuit and has GPIO output assigned per table below.

Shutdown Switch

The shutdown service daemon checks GPIO pin 7 of the Nano J41 header every second and will initiate a system shutdown if the input is pulled high by the shutdown switch for three consecutive seconds.