Smartphone app promises crowdsourced road roughness index and fuel efficient routing

By Michael Brenneis

The ability of smartphones to collect reams of data is significantly expanding crowdsourcing opportunities. An accelerometer is used by smartphones to change screen orientation or count footfalls, among other uses. But it is also capable of recording the force of acceleration—resulting from movement or gravity—100 times per second. And the movements it detects can be quite small. A new app developed by researchers associated with the MIT Concrete Sustainability Hub is harnessing this flood of data to measure road roughness in a way that could have far-reaching effects.

The Carbin app is gearing up to crowdsource data from its users, and full functionality is expected later in March 2019. The developers hope eventually to layer the collected roughness data onto interactive maps, and use routing algorithms to direct drivers onto smoother, fuel-saving routes.

In simple terms the International Roughness Index (IRI) represents the motion of a vehicle’s suspension orthogonal to the road surface over a given distance. Vehicles consume more fuel traveling on rougher roads. Given enough data points, the Carbin algorithm can isolate road roughness, as well as tire and suspension issues, by removing the baseline noise of the vehicle itself. The app can calculate a road’s IRI, or determine the percentage of fuel consumption attributable to the roughness of the road.

The application of this technology could be widespread. Truck fleets could be routed to the smoothest road surface, conserving fuel and increasing profit margins. Tire condition could be monitored and under-inflated or damaged tires identified before they cause a problem. Municipalities may be able to get a better picture of the state of their roads without resorting to costly studies or relying on spotty visual inspection.

Roads are designed to accommodate the use that is predicted. As with other crowd-sourcing apps such as Waze, which routes vehicles to avoid congestion—even onto residential streets not designed for increased traffic—Carbin could have unintended consequences. Routing vehicles onto less degraded roads, not designed for increased traffic, could speed up their degradation. But Carbin CEO Jake Roxon has a broader purpose in mind. He says the app “will be able to consider these factors in rerouting the traffic so to minimize the overall degradation rate of the network, thus contributing to enhancing the network performance and [diminishing] the associated environmental impact.”

Michael Brenneis is an Associate Researcher at SSTI.