Volvo has spent a decade designing a radar-and-camera system called Pedestrian Detection that, hidden in the grille of a car, can recognize human beings up ahead and step on the brakes if the driver doesn't.
This innovation is designed to work in city traffic, at speeds of up to about 25 kilometers per hour (approximately 16 miles per hour).
That isn't a totally arbitrary figure - as Dr. Stephen Watkins at the U.K. National Health Service has said:
A pedestrian hit by a car at 40 mph has a 95% chance of being killed, at 30 mph this becomes 50% and at 20 mph it becomes 5%.
So 20 mph is plenty, when it comes to pedestrian safety. And aren't we all pedestrians at some point?
Human beings have chased speed since the beginning of time though human bodies aren't designed to go faster than about 15 miles per hour, or to easily withstand the forces of acceleration (to say nothing of the effect of crashing at high speeds).
Thus Slow Food, a great movement to help us appreciate the time it takes to craft and eat healthy, traditional and delicious foods, has also arrived for cars, for bikes, and for cities.
Simon and† Garfunkel said it best back in the 59th Street Bridge Song in 1966:
Slow down,
you move too fast
you've got to make the morning last
just kicking down the cobblestones
looking for fun and feeling groovy.
These days, nobody's feeling groovy, but cities and towns are starting to realize the value of calming traffic to safer, and by extension, higher quality-of-life speeds. Portsmouth, U.K., is Britain's first town to set a 20 mph speed limit through all residential roads.
According to World Streets writer Rory McMullan, the shift has reduced speeds, traffic accidents, and traffic casualties.
No word yet on whether Portsmouthians are feeling any more groovy, however.
For more articles by Graham Hill click here.
Read more about the positive effects of traffic calming at TreeHugger:
Cardboard Kids Slow Down Drivers
Should Cyclists Be Allowed to Blow Through Stop Signs
The Traffic Calming Chicane
Street Films' Animation Explains Diverters as Traffic-Calming Measure
Biking Boris Battles Death (Unknowingly) and Other City Cycling Tidbits