ftc-decode

name: ftc-decode description: Expert knowledge about FTC DECODE game (2025-2026 season). Use when planning autonomous strategies, understanding scoring rules, discussing field layout, working with artifacts, pattern matching, gate mechanics, or optimizing game-specific robot behaviors.

FTC DECODE Game Skill

This skill provides comprehensive knowledge about FTC DECODE, the 2025-2026 FIRST Tech Challenge game season. Use this when planning strategies, programming autonomous routines, or making game-specific decisions.

Game Concept

DECODE is a competition where two alliances of two teams each compete to:

1. Score artifacts (purple and green balls) into their alliance's goal
2. Build patterns on the classifier ramp matching the obelisk's motif
3. Return to base before time expires for endgame bonuses

The game features a randomized element through an obelisk that determines one of three color patterns (GPP, PGP, or PPG) for bonus points.

Game Phases

Autonomous Period (30 seconds)

Robots operate independently with pre-programmed instructions. Scoring opportunities:

• Leave: 3 points (moving completely off launch lines)
• Classified artifacts: 3 points each (artifacts through goal and onto ramp)
• Overflow artifacts: 1 point each (artifacts bypassing ramp/classifier)
• Pattern matching: 2 points per correctly positioned artifact

Teleop Period (2 minutes)

Driver-controlled gameplay with continued scoring plus additional opportunities:

• All autonomous scoring continues (leave, classified, overflow, pattern)
• Depot scoring: 1 point per artifact positioned over depot zone
• Partial base return: 5 points (robot partially in base zone)
• Full base return: 10 points (robot fully supported by base zone tile)

Endgame Requirements

Base return must occur before match time expires:

• Partial return: Robot touching base zone but also supported by other field elements
• Full return: Robot only supported (directly or transitively) by the tile in the base zone

Field Layout

The playing field is approximately 144" × 144" and includes:

Goals (2 - one per alliance)

• Triangular opening at top for artifact entry
• Archway exit where artifacts emerge
• Connected to classifier mechanism
• Located on opposite sides of field for each alliance

Classifiers (2 - one per alliance)

Attached to each goal with three components:

1. Square: Collection area beneath goal
2. Ramp: 9 indexed positions for pattern building (3×3 arrangement)
3. Gate: Push-to-open mechanism that releases classified artifacts

Obelisk (1 - outside field)

• Triangular prism positioned outside playing field
• Displays one of three patterns via rotation
• Randomized before match starts
• Defines the motif for pattern scoring

Loading Zones (2 - one per alliance)

• Areas where human players can manage artifacts
• Used for staging artifacts for robot pickup
• Location for human player interaction during match

Base Zones (2 - one per alliance)

• 18" × 18" areas for endgame parking
• Robots must return here for base points
• Two levels of achievement: partial and full return

Launch Zones (multiple per alliance)

• Triangular areas from which robots can propel artifacts
• Starting positions for autonomous period
• Multiple options for strategic positioning

Game Elements: Artifacts

Total: 36 artifacts

• 24 Purple (P) artifacts
• 12 Green (G) artifacts

Specifications:

• Gopher ResisDent balls
• Approximately 5 inches in diameter
• Two distinct colors for pattern building
• Can be controlled, transported, and scored

Control Limit: Maximum 3 artifacts in simultaneous robot possession

Scoring Breakdown

Autonomous Period (30 seconds)

Maximum theoretical autonomous: ~150+ points (with perfect execution)

Teleop Period (2 minutes)

All autonomous scoring continues PLUS:

Ranking Points

Teams earn bonus ranking points (RP) for achieving thresholds:

• Movement threshold (leave points)
• Goal scoring threshold (classified + overflow)
• Pattern completion threshold (pattern matching)

Ranking points determine tournament seeding and advancement.

Pattern Mechanics

The Three Motifs

The obelisk reveals one of three patterns before each match:

1. GPP - Green, Purple, Purple
2. PGP - Purple, Green, Purple
3. PPG - Purple, Purple, Green

Pattern Application

The selected motif is repeated 3 times to create a 9-position pattern on the ramp:

Example - GPP motif selected:

Ramp positions (3×3 grid):
[1][2][3]
[4][5][6]
[7][8][9]

Pattern:
[G][P][P]
[G][P][P]
[G][P][P]

Position indexing: Check official manual for exact ramp position numbering.

Pattern Scoring Strategy

• Each artifact correctly positioned: +2 points (autonomous or teleop)
• Artifacts must be in correct position AND correct color
• Can complete pattern incrementally throughout match
• Strategic decision: balance pattern scoring vs overflow scoring

Gate Mechanics

The gate is a robot-activated, push-to-open mechanism:

Functionality

• Located at the bottom of the classifier ramp
• Releases classified artifacts when opened
• Allows artifacts to exit and potentially be re-scored
• Can be used strategically for cycling

Strategic Considerations

• Timing: When to open gate for artifact release
• Cycling: Re-scoring artifacts for additional points
• Denial: Keeping gate closed to maintain pattern
• Opponent interaction: Gate can affect both alliances' strategies

Strategic Concepts

Autonomous Strategy

High-priority goals:

1. Leave - Easy 3 points, required for ranking points
2. Classified artifacts - 3 points each, builds toward pattern
3. Pattern positioning - Additional 2 points per correct placement
4. Speed vs accuracy - Balance quantity of artifacts vs pattern correctness

Autonomous autonomous considerations:

• Pre-load artifacts for scoring
• Path planning to loading zones or pre-placed artifacts
• Vision detection for pattern identification
• Precision placement for pattern matching

Teleop Strategy

Scoring priorities:

1. Continue pattern building - 5 points per artifact (3 classified + 2 pattern)
2. Overflow scoring - 1 point fallback if pattern complete
3. Depot scoring - 1 point for simple placement
4. Prepare for endgame - Position for base return

Time management:

• First 90 seconds: Maximize artifact scoring
• Last 30 seconds: Position for base return
• Final 10 seconds: Execute full base return if possible

Endgame Strategy

Base Return Options:

• Partial return (5 pts): Easier, robot touching base but can be supported by other elements
• Full return (10 pts): Harder, robot ONLY supported by base zone tile (directly or transitively)

Risk vs Reward:

• Going for full return risks missing partial return window
• Partial return is safer but worth half the points
• Consider alliance partner coordination

Pattern vs Overflow Decision

Pattern scoring (classified + pattern match):

• 3 points (classified) + 2 points (pattern) = 5 points per artifact
• Requires precision and correct color placement
• Limited by pattern positions (9 total)

Overflow scoring (classified only):

• 1 point per artifact (if bypasses ramp)
• OR 3 points per artifact (if classified but no pattern bonus)
• Easier, higher throughput
• Unlimited capacity

Decision factors:

• Pattern completion status
• Robot precision capabilities
• Time remaining
• Artifact colors available

Integration with pedroPathing

When planning autonomous paths for DECODE:

Field Coordinates

Define key positions in your autonomous:

// Example positions (adjust to actual field measurements)
val startPose = Pose(9.0, 9.0, Math.toRadians(0.0))
val goalPose = Pose(120.0, 120.0, Math.toRadians(45.0))
val loadingZone = Pose(12.0, 60.0, Math.toRadians(-90.0))
val basePose = Pose(18.0, 18.0, Math.toRadians(0.0))

Common Autonomous Patterns

Pattern 1: Score pre-load + pickup + score

SequentialCommandGroup(
    FollowPedroPath(pathing, paths.startToGoal),
    ScoreArtifact(spiceRack, shooter),  // Score pre-load
    FollowPedroPath(pathing, paths.goalToLoading),
    IntakeArtifact(intake, spiceRack),  // Pick up from loading
    FollowPedroPath(pathing, paths.loadingToGoal),
    ScoreArtifact(spiceRack, shooter),  // Score second artifact
    FollowPedroPath(pathing, paths.goalToBase)  // Park for leave points
)

Pattern 2: Parallel intake while driving

ParallelRaceGroup(
    FollowPedroPath(pathing, paths.startToArtifact),
    RunIntake(intake)
).andThen(
    FollowPedroPath(pathing, paths.artifactToGoal),
    ScoreArtifact(spiceRack, shooter)
)

Vision Integration

Use Limelight for pattern detection:

// Detect obelisk pattern before autonomous
val detectedPattern = limelight.getMotif()  // GPP, PGP, or PPG

// Adjust scoring strategy based on pattern
when(detectedPattern) {
    Motif.GPP -> scoreGreenFirst()
    Motif.PGP -> scorePurpleFirst()
    Motif.PPG -> scorePurpleFirst()
}

Codebase Integration

Subsystems Used for DECODE

From common/subsystems/:

1. Drivetrain - Navigate field, approach goals and loading zones
2. Odometry - Track position for autonomous navigation
3. Shooter - Launch artifacts into goal (if using shooter mechanism)
4. SpiceRack - Index and manage artifacts with color detection (green/purple)
5. Intake - Collect artifacts from field and loading zones
6. Limelight - Detect obelisk pattern (GPP, PGP, PPG) and AprilTags for localization
7. Turntable - Aim toward goal (if needed for scoring)

Color Detection

SpiceRack already includes color detection for DECODE artifacts:

// From Constants.kt and codebase
ARTIFACT_GREEN  // Green artifact detection
ARTIFACT_PURPLE // Purple artifact detection

Use this to:

• Identify artifacts before intake
• Sort artifacts for pattern matching
• Verify correct artifact before scoring

Pattern Matching Logic

Implement pattern verification:

data class Pattern(val positions: List<ArtifactColor>) {
    companion object {
        val GPP = Pattern(listOf(GREEN, PURPLE, PURPLE, GREEN, PURPLE, PURPLE, GREEN, PURPLE, PURPLE))
        val PGP = Pattern(listOf(PURPLE, GREEN, PURPLE, PURPLE, GREEN, PURPLE, PURPLE, GREEN, PURPLE))
        val PPG = Pattern(listOf(PURPLE, PURPLE, GREEN, PURPLE, PURPLE, GREEN, PURPLE, PURPLE, GREEN))
    }
}

fun getRequiredColor(pattern: Pattern, position: Int): ArtifactColor {
    return pattern.positions[position]
}

Quick Reference

Scoring Values

• Leave: 3 pts
• Classified: 3 pts
• Overflow: 1 pt
• Pattern match: 2 pts (per artifact)
• Depot: 1 pt
• Partial base: 5 pts
• Full base: 10 pts

Key Numbers

• Match duration: 2:30 (30s auto + 2:00 teleop)
• Total artifacts: 36 (24 purple + 12 green)
• Control limit: 3 artifacts
• Base zone: 18" × 18"
• Field size: 144" × 144"
• Artifact diameter: ~5 inches
• Pattern positions: 9 (3×3 grid)

Three Patterns

1. GPP - Green, Purple, Purple (repeated 3×)
2. PGP - Purple, Green, Purple (repeated 3×)
3. PPG - Purple, Purple, Green (repeated 3×)

Priority Checklist

• Leave starting zone (+3 pts, required for RP)
• Detect obelisk pattern (vision/manual)
• Score pre-loaded artifacts
• Collect and score additional artifacts
• Build pattern on ramp for bonus points
• Return to base before time expires (+5 or +10 pts)

Common Questions

Q: Can we score artifacts in opponent's goal? A: Check official manual - typically no, only alliance-specific goals.

Q: What happens if we control more than 3 artifacts? A: Penalty - see official manual for violation consequences.

Q: Do pattern points apply in both autonomous and teleop? A: Yes, pattern matching scores 2 additional points per correctly placed artifact in both periods.

Q: Can we move artifacts from ramp back to field? A: Yes, using the gate mechanism to release classified artifacts.

Q: Is there a penalty for entering opponent's zones? A: Check official manual for zone restrictions and penalties.

Resources

• Official Manual: https://ftc-resources.firstinspires.org/ftc/game/cm-html/DECODE_Competition_Manual_TU17.htm
• FTC Resources: https://ftc-resources.firstinspires.org/
• Game Updates: Check for Technical Updates (TU) regularly
• Forum: FTC Community forums for rule clarifications
• This Project's Vision: common/subsystems/Limelight.kt for pattern detection
• Color Constants: common/Constants.kt for ARTIFACT_GREEN and ARTIFACT_PURPLE

Version

This skill is based on:

• Competition Manual Version: TU17 (Technical Update 17)
• Season: 2025-2026 DECODE
• Last Updated: January 2026

Check for game updates and technical updates throughout the season for rule changes or clarifications.