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Zero to Robot

  • Introduction
  • Step 1: Building your Robot
    • Introduction to FRC Robot Wiring
  • Step 2: Installing Software
    • Offline Installation Preparation
    • Installing the FIRST Driver Station
    • WPILib Installation Guide
    • Python Installation Guide
    • Next Steps
  • Step 3: Preparing Your Robot
    • Imaging your Systemcore
    • Programming your Radio
    • Using the OpenMesh OM5P Radio
  • Step 4: Programming your Robot
    • Creating your Test Drivetrain Program (Java/C++/Python)
    • Running your Test Program

Control System Overviews

  • Hardware Component Overview
  • Software Component Overview

Programming Basics

  • What is WPILib?
  • 2027 Overview
    • Known Issues
    • New for 2027
    • Quick Start for Returning Teams
    • 2026 Game Data Details
    • Removed features
  • VS Code Overview
    • Visual Studio Code Basics and the WPILib Extension
    • WPILib Commands in Visual Studio Code
    • Creating a Robot Program
    • 3rd Party Libraries
    • Building and Deploying Robot Code
    • Viewing Console Output
    • Debugging a Robot Program
    • Importing Last Year’s Robot Code
  • Dashboards
    • Choosing a Dashboard
    • Glass
      • Introduction to Glass
      • Establishing NetworkTables Connections
      • Glass Widgets
      • Widgets for the Command-Based Framework
      • The Field2d Widget
      • The Mechanism2d Widget
      • Plots
    • AdvantageScope
    • Elastic
    • Troubleshooting Dashboard Connectivity
  • Telemetry
    • Telemetry: Recording and Sending Real-Time Data
    • New for 2025: Robot Telemetry with Annotations (Java Only)
    • Recording Faults with Persistent Alerts
    • On-Robot Telemetry Recording Into Data Logs
    • Downloading & Processing Data Logs
    • Third-Party Telemetry Libraries
  • RobotPy Python Programming
    • Python Installation Guide
    • Installing the FIRST Driver Station
    • pyproject.toml usage
    • RobotPy subcommands
      • Deploy Python program to roboRIO
  • Hardware APIs
    • Motors APIs
      • Using Motor Controllers in Code
      • PWM Motor Controllers in Depth
      • Using the WPILib Classes to Drive your Robot
      • Repeatable Low Power Movement - Controlling Servos with WPILib
    • Pneumatics APIs
      • Operating Pneumatic Cylinders
      • Generating and Storing Pressure
    • Sensors
      • Sensor Overview - Software
      • Accelerometers - Software
      • Gyroscopes - Software
      • Encoders - Software
      • Analog Inputs - Software
      • Analog Potentiometers - Software
      • Digital Inputs - Software
      • Programming Limit Switches
    • Miscellaneous Hardware APIs
      • Addressable LEDs
  • CAN Devices
    • Using CAN Devices
    • Pneumatics Control Module
    • Pneumatic Hub
    • Power Distribution Module
    • Third-Party CAN Devices
    • FIRST CAN Device Specifications
  • Basic Programming
    • Git Version Control Introduction
    • The C++ Units Library
    • The Java Units Library
    • Joysticks
    • Coordinate System
    • Setting Robot Preferences
    • Robot Project Deploy Directory
    • Reading Stacktraces
    • Treating Functions as Data
    • Get Alliance Color
    • Java Garbage Collection
    • Using Utility Mode
  • Support Resources
  • FRC Glossary

API Docs

  • WPILib Java API Docs
  • WPILib C++ API Docs
  • WPILib Python API Docs

Software Tools

  • Driver Station
    • FRC Driver Station Powered by NI LabVIEW
    • Driver Station (Operator Console) Best Practices
    • Driver Station Log File Viewer
    • Driver Station Errors/Warnings
    • Driver Station Timing Viewer
    • Manually Setting the Driver Station to Start Custom Dashboard
  • Robot Simulation
    • Introduction to Robot Simulation
    • Simulation Specific User Interface Elements
    • Glass Widgets
    • Widgets for the Command-Based Framework
    • The Field2d Widget
    • Plots
    • Physics Simulation with WPILib
    • Device Simulation
    • Drivetrain Simulation Tutorial
      • Drivetrain Simulation Overview
      • Step 1: Creating Simulated Instances of Hardware
      • Step 2: Creating a Drivetrain Model
      • Step 3: Updating the Drivetrain Model
      • Step 4: Updating Odometry and Visualizing Robot Position
    • Unit Testing
  • OutlineViewer
  • WPIcal

Advanced Programming

  • Vision Processing
    • Vision Introduction
      • What is Vision?
      • Strategies for Vision Programming
      • Identifying and Processing the Targets
      • Read and Process Video: CameraServer Class
    • Vision with WPILibPi
      • A Video Walkthrough of using WPILibPi with the Raspberry Pi
      • Using a Coprocessor for vision processing
      • Using the Raspberry Pi for FRC
      • What you need to get the Pi image running
      • Installing the image to your MicroSD card
      • The Raspberry PI
      • Using CameraServer
      • Thresholding an Image
      • Morphological Operations
      • Working with Contours
      • Basic Vision Example
    • AprilTag Introduction
      • What Are AprilTags?
    • Vision on the RoboRIO
      • Using the CameraServer on the roboRIO
      • Using Multiple Cameras
      • CameraServer Web Interface
  • Command-Based Programming
    • Commands v2 Programming
      • What Is “Command-Based” Programming?
      • Commands
      • Command Compositions
      • Subsystems
      • Binding Commands to Triggers
      • Structuring a Command-Based Robot Project
      • Organizing Command-Based Robot Projects
      • The Command Scheduler
      • A Technical Discussion on C++ Commands
      • PID Control in Command-based
      • Motion Profiling in Command-based
      • Combining Motion Profiling and PID in Command-Based
  • Kinematics and Odometry
    • Introduction to Kinematics and The ChassisSpeeds Class
    • Differential Drive Kinematics
    • Differential Drive Odometry
    • Swerve Drive Kinematics
    • Swerve Drive Odometry
    • Mecanum Drive Kinematics
    • Mecanum Drive Odometry
  • NetworkTables
    • What is NetworkTables
    • NetworkTables Tables and Topics
    • Publishing and Subscribing to a Topic
    • NetworkTables Instances
    • NetworkTables Networking
    • Listening for Changes
    • Writing a Simple NetworkTables Robot Program
    • Creating a Client-side Program
    • Migrating from NetworkTables 3.0 to NetworkTables 4.0
    • Reading Array Values Published by NetworkTables
  • Path Planning
    • Choreo
  • Systemcore
    • Systemcore Introduction
    • Imaging your Systemcore
    • Systemcore Web Dashboard
    • roboRIO FTP
    • roboRIO User Accounts and SSH
    • roboRIO Brownout and Understanding Current Draw
  • Advanced GradleRIO
    • Using External Libraries with Robot Code
    • Setting up CI for Robot Code using GitHub Actions
    • Using a Code Formatter
    • Gradlew Tasks
    • Including Git Data in Deploy
    • Using Compiler Arguments
    • Profiling with VisualVM
    • JVM Runtime error
  • Advanced Controls
    • A Video Walkthrough of Model Based Validation of Autonomous in FRC
    • Advanced Controls Introduction
      • Control System Basics
      • Picking a Control Strategy
      • Introduction to DC Motor Feedforward
      • Introduction to PID
      • PID Introduction Video by WPI
      • Introduction To Controls Tuning Tutorials
      • Tuning a Flywheel Velocity Controller
      • Tuning a Turret Position Controller
      • Tuning a Vertical Arm Position Controller
      • Tuning a Vertical Elevator with Motion Profiling
      • Common Control Loop Tuning Issues
    • Filters
      • Introduction to Filters
      • Linear Filters
      • Median Filter
      • Slew Rate Limiter
      • Debouncer
    • Geometry Classes
      • Translation, Rotation, and Pose
      • Transformations
    • System Identification
      • Introduction to System Identification
      • Creating an Identification Routine
      • Running the Identification Routine
      • Loading Data
      • Viewing Diagnostics
      • Analyzing Data
      • Additional Utilities and Tools
    • Controllers
      • PID Control in WPILib
      • Feedforward Control in WPILib
      • Combining Feedforward and PID Control
      • Trapezoidal Motion Profiles in WPILib
      • Combining Motion Profiling and PID Control with ProfiledPIDController
      • Bang-Bang Control with BangBangController
    • Trajectory Generation and Following with WPILib
      • Trajectory Generation
      • Trajectory Constraints
      • Manipulating Trajectories
      • Transforming Trajectories
      • LTV Unicycle Controller
      • Troubleshooting
    • State-Space and Model Based Control with WPILib
      • Introduction to State-Space Control
      • State-Space Controller Walkthrough
      • State Observers and Kalman Filters
      • Pose Estimators
      • Debugging State-Space Models and Controllers
    • Controls Glossary
  • Convenience Features
    • Scheduling Functions at Custom Frequencies
    • Event-Based Programming With EventLoop

Examples and Tutorials

  • WPILib Example Projects
  • Third Party Example Projects

Hardware

  • Hardware - Basics
    • Hardware Component Overview
    • Introduction to FRC Robot Wiring
    • Wiring Best Practices
    • CAN Wiring Basics
    • Wiring Pneumatics - CTRE Pneumatic Control Module
    • Wiring Pneumatics - REV Pneumatic Hub
    • Status Light Quick Reference
    • Robot Preemptive Troubleshooting
    • Robot Battery Basics
  • Hardware Tutorials
    • Motors for Robotics Applications
    • Sensing and Sensors
    • Pneumatics
    • Power Transmission
  • Sensors
    • Sensor Overview - Hardware
    • Analog Inputs - Hardware
    • Analog Potentiometers - Hardware
    • Digital Inputs - Hardware
    • Proximity Switches - Hardware
    • Encoders - Hardware
    • Gyroscopes - Hardware
    • Accelerometers - Hardware
    • LIDAR - Hardware
    • Triangulating Rangefinders
    • Serial Buses

Romi and XRP Support

  • Getting Started with Romi
    • Romi Hardware & Assembly
    • Imaging your Romi
    • Getting to know your Romi
    • Romi Hardware Support
    • The Romi Web UI
    • Programming the Romi
  • Getting Started with XRP
    • XRP Hardware, Assembly, and Imaging
    • Getting to know your XRP
    • XRP Hardware Support
    • The XRP Web UI
    • Programming the XRP

Robot Networking

  • Networking Introduction
    • Networking Basics
    • IP Configurations
    • Systemcore Network Troubleshooting
    • Windows Firewall Configuration
    • Measuring Bandwidth Usage
  • Networking Utilities
    • Port Forwarding

Contributing

  • Contributing to wpilib-docs
    • Contribution Guidelines
    • Style Guide
    • Build Instructions
    • Draw.io Saving Instructions
    • Translations
    • Top Contributors
    • Top Translators
    • TODO List
  • Developing with allwpilib
    • Overview
    • Styleguide & wpiformat
    • Building with CMake
    • Using Development Builds
    • Maven Artifacts
    • Contributor Guidelines
    • NetworkTables 4 Protocol Spec

Legal

  • Privacy Policy

Issues

  • Report a Documentation Issue
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AprilTag Introduction¶

  • What Are AprilTags?
    • Application to FRC
    • Software Support
    • Processing Technique
    • Usage
    • 2D to 3D Ambiguity
    • Adjustable Parameters
    • Further Learning
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What Are AprilTags?
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Basic Vision Example
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Last updated on Aug 17, 2024