Photos: The bus that doesn't need a driver

Look no hands

Most passengers would react in horror if their bus veered across the road while the driver sat back, hands off the steering wheel.

But scientists from the University of California, Berkeley, have steered a high tech bus, seen here, using nothing but magnets.

The 60-foot research bus was demonstrated along a one-mile stretch of East 14th Street in San Leandro, specially embedded with a series of magnets for the test.

Sensors and processors on board the bus detected the magnets in the pavement and controlled the steering based upon the information they received.

The automated steering drove with a level of accuracy that puts human drivers to shame, pulling into stops within one centimetre of the kerb.

Researchers say such precision docking would help shave precious seconds off of the time to load and unload passengers at each stop, adding up to shorter journeys.

The ability to more precisely control the movement of the bus also reduces the width of the lane required for safe travel from 12 feet to 10 feet, researchers say.

Photo credit: UC Berkeley

The California Department of Transportation (Caltrans) has provided $320,000 to fund this Automated Bus Guidance System demonstration project, conducted by the California Partners for Advanced Transit and Highways (PATH) program based at UC Berkeley.

The test marks the first use of magnetic guidance technology to steer buses on a public road, seen in action here, and UC Berkley researchers say that driverless vehicles have taken a leap towards becoming reality.

Wei-Bin Zhang, PATH transit research program leader at UC Berkeley, said in a statement: "We have seen increasing interest among transit agencies in this technology because of its potential to bring the efficiency of public bus service to a level approaching that of light rail systems, but at a much lower overall cost."

Photo credit: UC Berkeley

Sensors mounted under the bus measured the magnetic fields created from the roadway magnets, which were placed beneath the pavement surface, one metre apart along the centre of the lane.

The information was translated into the bus's lateral and longitudinal position by an on-board computer, which then directed the vehicle to move accordingly.

With the vehicle travelling at 60 mph, data from 27 metres of roadway was read and processed in one second. The accuracy of the system can be seen by the closeness to the kerb here.

Zhang added that the system is robust enough to withstand a wide range of conditions, including rain or snow.

Researchers also said that magnetic guidance technology allows for a bus to safely follow closely behind another.

Extra vehicles, much like extra cars on light rail trains, could be added during peak commute times.

Photo credit: UC Berkeley

California PATH researchers have been studying magnetic guidance systems, such as the one embedded in the pavenment here, as a means of controlling vehicle movement for nearly 20 years, with significant funding from Caltrans and the US Department of Transportation.

They have shown it controlling a platoon of passenger cars speeding along busy roads in Southern California, as well as running industrial vehicles such as snowplows and tractor trailers in Northern California and Arizona.

Photo credit: UC Berkeley

Test track experiments with the technology have demonstrated full vehicle control - including braking and accelerating - creating a "auto-pilot" system for the bus. Despite the computer's involvement, the driver can resume manual control of the bus at any time.

With modification of surrounding pavements, as seen here, the system could be integrated into traditional bus routes, or used as part of more advanced bus systems, which could include a dedicated lane for the automatic vehicles.

Photo credit: UC Berkeley

The magnetic bus system compares favourably in price with light rail, coming in at about $278m for a possible automated bus system in California compared to the $2bn cost of a light railway network.

The automated bus guidance system project will receive funding from the US Department of Transportation and Californian transport bodies as it becomes part of the federal Vehicle Assist and Automation Program.

Here is a cross section of a core from the pavement with the magnet embedded in it.

Photo credit: UC Berkeley