The Formula for Perfect Parallel Parking

Here’s a problem that may be harder than P vs. NP for some people: parallel parking. Looking for a chance to “show how we can apply mathematics to understanding something that we all share,” mathematician Simon Blackburn of University of London’s Royal Holloway College developed a formula that tells you exactly how much extra length (beyond the length of your car) you need to have to even consider parallel parking in a given space. Blackburn’s formula is fairly comprehensive, taking into consideration the following variables:

r is the radius of my car’s kerb-to-kerb turning circle, l is my car’s wheel-base (the distance between the centres of the front wheel and the corresponding back wheel), k is the distance from the centre of the front wheel to the front of the car, and w is the width of one of the parked cars: the one near the front of my car once I’ve parked.

(As most American readers have probably already guessed, ‘kerb’ is British for ‘curb’.) The story indeed has wide appeal, as the formula has seen mention in places as various as NPR, Fox News, the NY Daily News, and of course outlets in Britain like the Telegraph. Dr. Blackburn’s original paper can be found here.