Future car doors could ‘sense’ approaching cyclists

New technology ready for use by end of year

'Intelligent' car doors could sense approaching cyclists and prevent collisions like this

A new car door has been developed which will not open if a potential impact – such as an approaching cyclist – is detected.


The prototype looks like a normal door, but with an extra metal bar running through its centre. The magic component is the “haptic” – technology that gives tactile feedback in combination with ultrasonic sensors.

The bar moves freely and doesn’t affect the door’s movement unless inbuilt sensors detect a nearby obstacle at the same time as an accelerometer detects an attempt to open the door. The door’s swing is then restricted by a linear motor attached to the bar.

To make the system more user-friendly, the amount of door resistance is in proportion to the proximity of an object. This means that the closer a cyclist or other vehicle gets to the door, the harder it will be to open it.

Designed by Michael Graf of BMW and Michael Strolz of the University of Munich, the prototype still needs some work –  the ultrasonic sensors used to spot dangers have a limited field of view so the next version will use cameras that can span 180°.

Once the cameras are fitted, says Strolz: “We will be able to sense the complete workspace of the door and detect people walking by the car or cycling towards it.”

The technology could be fitted to production models within a year, but BMW have yet to make any decision on whether to roll it out.

A spokesman for the Royal Society for the Prevention of Accidents gave general support for the role of ‘active’ technology in making the road environment safer.

He said: “The use of sensors like this is starting to give vehicles the potential to make observations as well as the driver. More and more technology is going into active safety that prevents accidents rather than traditional passive measures like airbag and seatbelt designs that help after an accident.”


Some ‘active’ technology is already on the market – for example, parking and blind-spot sensors.