Scaling

How Wheels4Wheels can scale to more parameters, more cities, and more audiences.

Aerial drone view of Tallinn city streets
Aerial view of a city street with buses and traffic

Timeline

Wheels4Wheels has developed in four stages since 2024. From foundational research and building the pipeline, to validating the method in Tallinn and publishing data and tooling open-source. In it's fourth stage, with the method validated, the project focuses on widening features, expanding scope, and promoting adoption.

Stages
StagePeriodGoalDetails
Research & Development2024Develop methodologyFeasibility research

Parameter selection

Sensor evaluation and testing

First version of the pipeline
Tallinn Pilot2025/26Validate method550 km covered across all Tallinn districts

40.5M accelerometer readings processed into 66,088 surface ratings

Validated against existing OSM data and manual mapping

Engaged with OSM community
Public Launch2026Gain public supportFull methodology and dataset published

Processing pipeline released as open source

Project introduced through media campaign

Initiated conversations with map apps
Scaling2026/27Increase adoptionImplementation of more parameters

Expand scope in Tallinn, add new cities

Promote adoption of data by map apps

Scaling Directions

The pilot in Tallinn demonstrated that e-scooter sensor data can reliably map accessibility features such as surface quality. That result validates the approach and opens three directions for scaling.

Directions
  • More Parameters
  • More Cities
  • More Audiences

More Parameters

The pilot validated one parameter – surface quality. The same sensors and the same pipeline can capture more: surface type from vibration patterns, incline from gyroscope and GPS readings, and sidewalk features from onboard cameras. Each additional parameter can feed the Wheels4Wheels pipeline and result in standard OSM tags.

Surface Type

After surface quality, the next parameter is surface type: the accelerometer and gyroscope on Bolt scooters measure wheel vibrations and angular movements to identify pavement characteristics such as asphalt, cobblestone, concrete, or gravel. These readings are processed via the CLI to classify each street segment and automatically generate OSM-compatible surface=* tags.

Five street surfaces side by side: mossy cobblestone, smooth asphalt, loose gravel, packed earth, and cracked asphalt
Five ground surfaces side by side

Incline

Incline is derived from the gyroscope and GPS data, capturing the slope of sidewalks, ramps, and streets. The CLI computes the average and maximum gradients for each segment and can assign the appropriate OSM-compatible incline=* or slope-related tags.

Two Bolt scooter riders on a terrace beside a glass building
Bolt scooter riders beside a glass building
Hendra Raud in her powered wheelchair ascending an asphalt slope
Hendra Raud in her wheelchair on an asphalt slope

Sidewalks, Curbs, Ramps

Onboard cameras capture sidewalks, curbs, ramps, and barriers; GPS pins each image to a location. An AI-based detection pipeline can identify accessibility-relevant features in the images, the CLI can link them to specific street segments to generate or validate for example sidewalk=, barrier=, and wheelchair=* tags – a visual complement to the sensor measurements.

Overhead view of pedestrians on a sidewalk and street
Pedestrians walking across paving and asphalt

More Cities

Because Bolt already operates e-scooters in 270+ cities across Europe, the infrastructure is in place for Wheels4Wheels to be replicated at scale. Every city has its own transport mix, street conditions, and regulations; yet the same e-scooter telemetry sensors and app infrastructure can be deployed without additional hardware. Mapping a new city adds little overhead. Publishing the results to OpenStreetMap makes cities comparable and speeds up the rollout of accessible-route mapping.

People walking and riding Bolt scooters on a promenade
People walking and riding Bolt scooters past cafe tables

More Audiences

While the dataset is designed to benefit wheelchair users, it also supports people pushing strollers, older people using walkers, and others who rely on mobility aids. Looking ahead, the same data can help micro-mobility and even autonomous vehicles plan their routes. The pipeline is built to take on new vehicle types and use cases as they appear.

A stroller photographed against a dark background
Stroller
A walker photographed against a dark background
Walker
An autonomous vehicle photographed against a dark background
Autonomous vehicle