Two-wheel future

Troubled US auto giant General Motors has joined forces with Segway to demonstrate a new type of vehicle that could change the way we move around in cities.

The PUMA (personal urban mobility and accessibility) prototype that the companies have jointly developed is an electrically powered two-seater that has only two wheels.

Weighing in at around 136kg, the prototype integrates a lithium-ion battery, a digital energy management system as well as dual electric wheel motors.

It maintains its balance through an array of angular rate sensors and accelerometers that determine the orientation and motion of the vehicle.

As it leans forward, the balance sensor assembly responds by requesting power to the motors to drive the wheels forward to maintain its balance.

Built to carry two passengers, it can travel at speeds of up to 56km/h, with a range of up to 56km between recharges.

Based on its current battery configuration, it costs less than 68 pence in electricity to recharge.

Segway would not reveal what such a vehicle might cost, simply saying that should the prototype ever be brought to market, it would probably cost less than most current small cars.