The Copenhagen Wheel - Smartphone linked Electric bicycle technology

Superpedestrian, a Cambridge-based start-up, started making the Copenhagen Wheel available for preorders on Tuesday.

According to the company, shipping begins spring 2014. For those following the development of the Copenhagen Wheel, this is news, as the wheel, which is designed to turn ordinary bicycles into smart electric hybrids, first made its debut in 2009 at the UN Climate Change Conference.

A key feature of the device is that it can compensate with additional power whenever needed.

Riding with the Copenhagen Wheel in place, the user can capture the energy dissipated while braking and cycling and save it for times when a boost is needed.

The device is powered by a removable 48-volt lithium battery. The battery charge time is four hours, according to the site.

The device is offered in 26-inch bicycle wheel size but the company said it plans to add more wheel sizes in future releases.

The company also said that, while presently selling only the wheel, it will soon sell both the wheel and bikes already equipped with the Copenhagen Wheel.

All actuation of the wheel is automatic by way of the pedals, through sensing and control algorithms.

When the rider pedals harder, such as when going uphill, the Copenhagen Wheel pushes with increasing power.

The product gets especially interesting when used along with a smartphone though the wheel can work without a phone.

With the phone, the Copenhagen Wheel becomes a personal trainer with feedback on exercise goals and fitness, and as a reporter, telling the user about traffic congestion and pollution levels.

The company uses a Bluetooth 4.0 wireless protocol.

The "earlybird" price is listed as $699.