Researchers at MIT have developed a new bicycle rear wheel—the Copenhagen Wheel—that can capture energy from braking and deliver the power back to provide a boost. The wheel, designed to be easily interchangeable with any standard bicycle’s rear wheel, also offers a variety of extra functions including real-time environmental sensing capabilities.
|A close-up of the Copenhagen Wheel, from MIT’s SENSEable City Lab. Click to enlarge.|
The Copenhagen Wheel differs from other electric bikes in that all components are packaged into one hub. There is no external wiring or bulky battery packs, making it retrofittable into any bike. The hub contains a motor, 3-speed internal hub gear, batteries, a torque sensor, GPRS and a sensor kit that monitors CO, NOx, noise (db), relative humidity and temperature. In the future, riders will be able to spec out a wheel according to riding habits and needs.
|Screenshot of a conceptual environmental monitoring application using crowd-sourced data. Click to enlarge.|
By using a series of sensors and a Bluetooth connection to the user’s iPhone, which can be mounted on the handlebars, the wheel can monitor the bicycle’s speed, direction and distance traveled, as well as picking up data on pollution in the air, and even the proximity of the rider’s friends.
The resulting data can both help the individual rider—for example, by providing feedback on fitness goals—and help the city (if the user opts to share the information) by building up a database of air quality, popular biking routes or areas of traffic congestion.
All of the generating, power assisting, sensing and communications equipment fits inside a plastic housing in the hub of the wheel, which was developed by Carlo Ratti, associate professor of the practice in MIT’s Department of Urban Studies and Planning (DUSP) and director of the SENSEable City Laboratory, and his team.
The whole generating and power-assisting system can be controlled through the pedals, requiring no switches or dials. Pedal backwards, and the regenerative braking is engaged, helping to recharge the system’s batteries; pedal fast, and you get the extra boost of power. “Everything is controlled by your feet,” Ratti explains.
The city of Copenhagen, site of the UN Conference on Climate Change, has been a sponsor of the research (along with the Italian company Ducati, and the Italian environment ministry), and the city has already placed an initial order for some of the innovative bicycle wheels, to be used by city workers.
The system was demonstrated in Copenhagen on 15 December for the benefit of conference attendees, and for a gathering of 400 city mayors from around the world.