Paralello-Parking: The Geometry of the Curb

If only Fermat had lived to the age of the automobile, he too might have grappled thusly:

How much extra length (above the length of your car) do you need to parallel park?

Maths (as they say in the U.K.) professor Simon Blackburn, working on behest of Vauxhall, has cracked the code (study can be downloaded at his page). Though much of it was beyond me — I suffer from horrible innumeracy — I was happy to learn about such things as “The Ackermann Linkage” (Ludlum-esque, that!). The footnotes also reveal that Blackburn is not the first to take a calculator to the curb — or kerb.

(Horn honk to Nathan)

This entry was posted on Monday, December 14th, 2009 at 3:48 pm and is filed under Parking, Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

4 Responses to “Paralello-Parking: The Geometry of the Curb”

  1. Jeff Says:

    Here’s a link to coverage with a bit of an explanation.

  2. David Says:

    Does he contrast it with how much space you’d need to do head-in parallel parking? Some people don’t seem to get that.

  3. Rich in CO Says:

    Answering David, above.
    The calculations are for the minimum distance required to clear the bumper of the front car and get the two curb-side wheels against the curb in one backing motion. As the author points out, you can’t get the rear wheels against the curb by driving forward (unless you mount the curb with the front wheel) so different criteria would have to be used for the pulling in forward version. It is clear to those of us who think geometrically that, with the steerable wheels at the front, quite a lot more space is required to parallel park using only forward motion than backing in . . . That and a space somewhat shorter than the calculated value can be parked in using a single pull forward with the steering on the opposite lock (as long as the rear wheels are permitted to be “near” rather than “against” the curb).

  4. fluffy_mike Says:

    This looks suspiciously like PR regurgitated as news. In a typical example a (no doubt, otherwise worthy) professor is paid to put their name to a formula that will become newsworthy in order to provide exposure for a particular company, in the case above: Vauxhall cars.

    Previous examples include…

    formula for saddest day of the year (Privilege Insurance)

    formula for happiest day of the year (Walls ice cream)

    equation for beer goggles (Bausch & Lomb)

    The accuracy of the maths and the desire to educate the public fall way short of the primary importance of exposing the name of the sponsor. The best thing to do when encountering such a story is to walk away.

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