Welcome

Welcome to the TCAT Wiki!⚓︎

This site explains how to use the open-source transportation accessibility tools and data developed by the Taskar Center for Accessible Technology (TCAT), especially OS-CONNECT (Washington State's connected pedestrian network dataset) and the TDEI (the infrastructure that stores and serves that data).

What's Your Goal?⚓︎

If you want to…	Use
View	OS-CONNECT Data Viewer — a view-only map; no GIS required
Download	TDEI Portal — manage accounts, API keys, and access controls
Plan	Walksheds — scenario planning, project proposal evaluation, and prioritization
Route	AccessMap — a public routing app, no portal required

User Journeys⚓︎

Choose your path: each one starts with the simplest document and then offers deeper options.

I want to use AccessMap as a resident or advocate

Do you want to find accessible, customized pedestrian routing and share it with others?

Get Started: Use AccessMap

I work for a jurisdiction or agency

Do you want to see what pedestrian infrastructure exists for your area, understand what the numbers mean, and decide what to do next?

Get Started: View the data and get a Jurisdiction Snapshot (PDF)

I want to import my existing data into the TDEI

Do you have existing datasets of sidewalks, curb ramps, bus stops, or other features that you want to get into the TDEI system?

Get Started: Check out our tutorials, guides, and examples: Curb Ramp Data into the TDEI, Core Edges in OSW, Custom Points in OSW, and much more in our Guides List!

Key Takeaways⚓︎

If you remember only three things, remember these:

OS-CONNECT is the dataset — It is a connected pedestrian network for Washington State (sidewalks, crossings, curb ramps, and related features) in the OpenSidewalks schema, organized so it can be used for routing and analysis.

TDEI is the platform — It is where data can be accessed for downloads and APIs, and where tools like AccessMap, Walksheds, AVIV ScoutRoute, and Workspaces connect to the data.

AccessMap is the router — It uses OpenSidewalks Schema-formatted data to provide custom accessible pedestrian routing without requiring specialized tools.

Projects⚓︎

OS-CONNECT — Washington State connected pedestrian network dataset.

TDEI — Platform infrastructure for storing, serving, and integrating transportation accessibility data.

OpenSidewalks — The data standard/schema used to represent pedestrian networks as a connected graph.

Workspaces — Tools for creating and maintaining OSW datasets (via editors like Rapid and AVIV ScoutRoute).

AccessMap — Accessible multimodal routing and trip planning.

Walksheds — Analysis of access to destinations using the pedestrian network.

AVIV ScoutRoute — Mobile app for adding data into the existing pedestrian map. AVIV ScoutRoute enables everyone to make structured, clear, and direct contributions of surveyed data to enhance it or keep it up to date.

Additional TCAT projects are listed on the TCAT website.

Architecture⚓︎

A multi‑tenant data sharing and exchange platform that supports the full lifecycle of transportation datasets, from collection and updates to publication and consumption.

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flowchart LR
    subgraph tools ["Data Generation"]
        ASR([AVIV ScoutRoute])
        RAP([Rapid])
        PRO([Prophet])
        IOS([iOSPointMapper])
    end

    subgraph tdei ["TDEI Core"]
        SVC["Ingestion & Validation
        Schema & Metadata
        Versioning & Lineage
        Quality Checks
        Access Control
        Publishing & Catalog
        APIs & SDKs"]
        TEN["Tenants:
        OS‑CONNECT
        Multnomah, OR
        Columbia, OR
        Montgomery, MD
        Baltimore, MD"]
    end

    subgraph apps ["Data Consumption"]
        AM([AccessMap])
        WS([Walksheds])
        AUD([Audiom])
        CVL([Conveyal])
    end

    ASR --> SVC
    RAP --> SVC
    PRO --> SVC
    IOS --> SVC
    SVC -.-> AM
    SVC -.-> WS
    SVC -.-> AUD
    SVC -.-> CVL

    click ASR "aviv-scoutroute/"
    click RAP "rapid/"
    click AM "accessmap/"
    click WS "walksheds/"
    click AUD "https://www.audiom.net/"
    click CVL "https://conveyal.com/"

    classDef tool fill:#90caf9,stroke:#1565c0,color:#000000
    classDef core fill:#ffe082,stroke:#f9a825,color:#000000
    classDef tenant fill:#ffcc80,stroke:#ef6c00,color:#000000
    classDef app fill:#a5d6a7,stroke:#2e7d32,color:#000000

    class ASR,RAP,PRO,IOS tool
    class SVC core
    class TEN tenant
    class AM,WS,AUD,CVL app

Quick Concepts⚓︎

New to this? If you are unfamiliar with some of this terminology, start with these short explanations to learn the concepts in less than 5 minutes:

Points of Interest (POIs)

A point of interest (POI) is a specific, identifiable location that is relevant to pedestrians or travelers, such as a transit stop, park entrance, business, public facility, or other amenity. In the context of TCAT projects, POIs are used alongside pedestrian network data to analyze access to destinations and services.

Connected Networks

A connected network is a graph of pedestrian infrastructure — sidewalks, crossings, curb ramps, and other paths — where all elements are linked as Nodes, Edges, and Zones forming a complete, traversable network. This is in contrast to disconnected or partial datasets where features exist in isolation.

Why this matters:

Routing — A connected network enables turn-by-turn pedestrian navigation and accessibility-focused trip planning (as in AccessMap), because every path segment connects to the next.
Analysis — Connectivity allows for network-level analyses (such as walksheds), enabling gap detection and equity assessments — computations that require understanding how infrastructure elements relate to one another.

Walksheds

A walkshed is the area reachable via a specified mode of transport from a given location within a specified travel time or distance, considering the actual pedestrian network. Unlike a simple radius, a walkshed accounts for real-world path connectivity, barriers, and infrastructure conditions. The Walksheds tool uses pedestrian network data to compute and visualize these areas, enabling analysis of access to amenities and services.

Learn more

Routing Profiles

A routing profile is a set of preferences and constraints that customize how a pedestrian route is calculated. For example, a routing profile may specify maximum acceptable incline, preference for curb ramps, or avoidance of unpaved surfaces. Tools like AccessMap use routing profiles to generate personalized, accessibility-aware directions based on individual needs.

Learn more

Tutorials, User Manuals, and Guides⚓︎

Looking for step-by-step instructions? Start with our full Guides List or try Ctrl+K Search!