Three-Point Turns

Apr

24

2014

One of the basic things you learn during driver’s ed is how to make a 3-point turn.

I have a problem with the 3-point turn.

Not doing the turn – the problem is with the name.

First off, here is a little video is made showing how a 3-point turn works. I did an cursory internet search for an animated diagram of 3-point turn, but didn’t find any. So I made one myself. It is not a very polished animation, because I drew the frames individually and pieced them together. I bet the better-looking videos out there use animation-rendering software, which I don’t have because I’m not planning on doing much animation.

animation of a 3-point turn driving maneuver

Now, having watched the video, you can see my problem with the name. Specifically, the number given to the maneuver.
Point #1 is obvious – it’s where the car stops and reverses direction.
Point #2 is also obvious – it’s where the car stops and reverses direction again.
Point #3 – I just made it up. I had to put a third point in there somewhere to make it a 3-point turn, but there is no place it fits.

Where is the third point in a 3-point turn?

I propose it should be called a 2-point turn.

Like this:

diagram of a 2-point turn driving maneuver

There are two natural points that anyone can locate.

Or you could call it a 3-direction turn. To make it sound fancier, we could use 3-vector turn.

diagram of a 3-vector turn driving maneuver

That works, because there are three natural vectors that anyone can locate.

That got me thinking, what would a real 3-point turn look like. I came up with this:

diagram of a real 3-point turn driving maneuver

Now that has three points, but four vectors, so the driver will continue in reverse. Maybe this is good for backing into parking spaces.

Also good for backing into spots is the 1-point turn:

diagram of a 1-point turn driving maneuver

I use that one every day.

And to finish the series, here is a 0-point turn:

diagram of a 0-point turn driving maneuver

I use this one in winter sometimes, but not when my wife or kids are in the car.

and I will turn you around, drive you on, take you up from the remotest parts of the north and bring you against the mountains of Israel.

Ezekiel 39:2

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This little article thingy was written by Some Guy sometime around 6:56 am and has been carefully placed in the Driving category.

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2 Responses to “Three-Point Turns”

  1. Ricky Anderson Says:
    April 24th, 2014 at 8:32 am

    So basically: Driving = Basketball.

  2. Some Guy Says:
    April 24th, 2014 at 11:46 am

    Yes, except travelling is legal.

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