Parking Meters That Prefer Cards Over Coins

More often than not, paying for a parking spot is a tedious affair: either you have to (hope that you) have enough coins on you, or you are confronted with a ticket machine whose designers were led more by the technical constraints inside the machine, than by the requirements of the user standing in front of it.

The experience with the parking meters in San Francisco is quite different: while the meters do accept coins, they also have a slot for pre-paid parking cards, which are available in $20 and $50 varieties.

Card in, observe, card out, done

To pay for your parking spot, you insert the card into the corresponding meter. At first, the display will show the current balance on the card for a few seconds, and then change to show the parking duration.

As long as you leave the card in the meter, the parking duration will increase in 7 or 8 minute increments (think “rounded 1/8-hour chunks:” 8, 15, 23, 30, 38, etc). The pace at which this happens is slow enough so you can easily follow along, and yet it is fast enough so you don’t feel like you have to excessively wait for the machine.

Once the meter displays your desired parking duration, you pull out the card, and you’re done. (On the next photo, note the chip symbol next to the card slot, indicating the orientation in which the card needs to be inserted.)

After I had taken the photos for this article, I realized that 38 minutes were not quite enough for what I was planning to do1, so I inserted the card again to see whether I could top up the meter, and it worked just fine.

Also works with parking ticket vending machines

In most cases, a dedicated meter is mounted right next to the corresponding parking spot. In others, you will have to pay at a vending machine, which adds a few extra steps, both in terms of walking up to the machine, as well as using it. Overall, though, this is the simplest and most convenient way to pay for car parking that I have encountered so far.

If you’re going to visit San Francisco and decide you want to buy one of these cards, you can find them at drugstores — I bought mine at the cosmetics(!) counter at a Walgreens — or via mail order directly from the San Francisco Municipal Transportation Authority.

Update 2010-10-07: Lars Feyerabend made an interesting comment about the chip symbol on the parking meter’s front panel:

I think the arrow is ambiguous. Representing the card or does it point to the side of the slot the chip should be at?

My intuitive interpretation of the symbol was that its arrow indicates the side that the chip should be on when inserting the card, i.e., the slot’s “south-western” edge.

Then again, the following picture was taken before the three others shown above, and as you can see, I was about to insert the card with the wrong side up. I had simply ignored the symbol altogether.

After musing over Lars’ comment, I wonder whether the chip symbol is as helpful for first-time users as I originally assumed. The good news is, though, that the meter will display an error message if you insert the card the wrong way, and does not fail silently.

  1. This being San Francisco, it did, of course, have something to do with eating out, and I hate being rushed when having good food. ↩

Making Toilet Paper Rolls Easier to Use

This just in from the Department of Usability Improvements in The Most Unusual Places: the manufacturer of this toilet paper has come up with an ingenious design for indicating where the roll “starts:” at the point where the end of the paper trail is glued on, this roll sports a little fold.

This fold makes it easy to see where the roll starts, and pulling on the fold conveniently breaks the glue bond.

What’s more, the fold can also be easily found by groping around for it. This not only makes it easier to use for the vision-impaired, but also improves its usability when used in one of the enclosed multi-roll dispensers often found in public restrooms.

The Bubble Cursor in Action

Anand Kulkarni has developed an interesting and fun demo of the bubble cursor, a UI concept conceived by Tovi Grossman and Ravin Balakrishnan.

Standard mouse pointers usually have just a single-pixel “hot spot.” It is this single pixel’s position that determines which UI element receives the click when the user presses a mouse (or trackpad, etc.) button. Because of the hot spot’s tiny size, it requires precision to hit a specific target on screen, especially if the target is small, too.2

Grossman and Balakrishnan address this problem by expanding the cursor’s “hot spot” to a circular “hot area.” The area’s size dynamically adapts to the cursor’s position in relation to nearby UI widgets so that, at any given time, exactly one widget is selected as the click target.

Grossman’s and Balakrishnan’s 2005 CHI paper (1.1MB PDF) explains the idea in detail and contains research which shows that the bubble cursor is consistently more effective than single-pixel and fixed-size area cursors.

Thanks to Anand’s JavaScript-based demo, you can try out the bubble cursor hands-on.

Unfortunately, though, you cannot disable or modify the area indicator around the cursor. It would be interesting to see whether changing the area indicator influences the feel of using the bubble cursor and, if so, in what way. I’d especially like to try out the demo without any visual feedback except highlighting of the current click target.

Found via Nat Torkington’s Four short links: 23 September 2010

Update 2010-10-05: Stuart Knightley has implemented the bubble cursor as a JavaScript bookmarklet that works with just about any webpage, so you can test this interaction concept in a real-life setting. As an extra feature not included in Kulkarni’s demo, this bookmarklet lets you toggle the display of the cursor’s click area.

  1. That’s Fitt’s Law at work again, of course. ↩