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INTER

LOCK

By Alpha31

Hana Benko, Laasya Aki, Dhiren Narne, Adithya Ravichandran

STEELHACKS XIII

2026

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The planning problem

  • Street changes are expensive, disruptive, and difficult to test before deployment.�
  • Cities often rely on historical crash records, traffic counts, and static models.�
  • Those approaches are poorly suited to evaluating rare near-miss interactions, temporary construction, weather conditions, and emerging AV traffic before a change is built.

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STEELHACKS XIII

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2026

  • Lane or intersection closures during construction
  • Signal timing and road redesigns
  • Heavy rain, snow, or traffic surges

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  • Pedestrian safety and wait times
  • Mixed human + autonomous traffic
  • Before/after tradeoffs in safety and throughput

What they need plan for

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What planners actually need to test

  • Lane or intersection closures during construction
  • Signal timing and road redesigns
  • Heavy rain, snow, or traffic surges

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Interlock is a scenario simulator for real Pittsburgh streets.

Real Pittsburgh Data

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SUMO & Monte Carlo

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Interactive 3D

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AI Voice

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  • Pittsburgh traffic, crash, road, and weather data
  • Stored in Tiger Data for simulation + analysis
  • SUMO models vehicles, pedestrians, and signals
  • Monte Carlo compares baseline vs. changed scenarios
  • Three.js visualizes real intersections and simulation replays
  • Users test construction, infrastructure, and AV scenarios
  • Gemini explains results and scenario tradeoffs
  • ElevenLabs enables voice interaction

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Tech Stack

Python & SUMO Engine

Executes microscopic traffic flow modeling and Monte Carlo simulations to derive speed, delay, and near-miss metrics.

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Data

Physics Engine

System Architecture

Analytics + Voice

  • Ingest real Pittsburgh crash, traffic-count, road-design, and weather data
  • Tiger Data / PostgreSQL stores normalized real-world data and high-frequency simulation results
  • Local data calibrates traffic demand and baseline conditions
  • Python + SUMO/TraCI simulate individual vehicles, pedestrians, signals, and road changes
  • Monte Carlo trials compare baseline vs. modified scenarios
  • Measures speed, delay, throughput, pedestrian wait, and Time-to-Collision conflict metrics

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  • FastAPI connects the interface to the engine
  • ElevenLabs provides the voice interface and reads scenario/street information aloud
  • Gemini interprets natural-language requests and translates them into model/scenario changes (only say this if this integration is actually working)

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Data

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Data

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Demo!

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Limitations & Next Steps

  • Currently focused on a small number of Pittsburgh intersections
  • Some traffic conditions are approximated where local data is limited
  • Near-miss metrics estimate risk, not actual future crashes
  • Autonomous vehicles are represented with simplified driving behavior
  • Future work: connect many intersections into larger city-wide simulations

STEELHACKS XIII

2026

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Hana Benko

Dhiren Narne

Adithya Ravichandran

Laasya Aki

Thank you!

hbenko@andrew.cmu.edu

dsnarne@andrew.cmu.edu

adithyar@andrew.cmu.edu

laki@andrew.cmu.edu