Wireless buttons halt London buses
Date: 20th August 2012
Topic: Switching On
Passengers aboard London’s new Eco-Routemaster hybrid buses can activate stop signals using their bodies as a source of energy, through energy-harvesting wireless technology. The act of pressing the bell-push generates enough electrical power for a wireless module to activate a remote stop signal for the driver.
The wireless bell push system, manufactured by UK company BMAC, is in tune with the green concept of the new London buses which, with their diesel hybrid technology, are among the most environmentally friendly vehicles of their kind.
Conventional push-buttons need to be connected to the signal receiver at the bus driver’s position via metres of cable, but the BMAC functions with a miniaturized energy converter from EnOcean. This small, battery-less module has a lifetime of more than 300 000 switching cycles. The radio signal is unique to each stop button, ensuring that there is no interference with other buttons in the bus or other buses nearby.
The energy harvesting wireless technology saves up to 100 metres of cabling, as well as installation effort, and it eliminates the need to replace defective cables, which can be time-consuming.