While the Apple Pencil is designed as a sketching tool for creative professionals, MacRumors reader Simon Gladman has created three Swift demo apps that show the accessory being used for three unconventional purposes -- as a weight scale, controlled synthesizer and 3D controller for image editing.

PencilScale


PencilScale, based on Goodman's Plum-O-Meter, is an experimental app that uses a homemade harness to turn the Apple Pencil into an electronic scale that is highly sensitive, but not incredibly accurate.

The experiment works by subtracting the touch's force from a base weight, which is "set as the current touch force when the 'zero' button is pressed," and multiplying it by 140 for a very rough weight in grams.

PencilSynth


PencilSynth is an AudioKit-powered synthesizer that can be controlled by the Apple Pencil depending on its orientation and position.

  • Apple Pencil's horizontal position on the screen controls frequency

  • Apple Pencil's vertical position on the screen controls the modulating multiplier

  • Apple Pencil's altitude angle controls the carrier multiplier

  • Apple Pencil's azimuth angle controls the modulation index

PencilController


PencilController is an experimental image processing app that uses the Apple Pencil as a controller for the fine setting of parameters on Core Image filters.

The demo has three image filtering modes:

  • Hue/Saturation - Apple Pencil's azimuth angle controls hue and its altitude angle controls the saturation

  • Brightness/Contrast - Apple Pencil's altitude angle along North/South controls contrast and the angle along West/East controls brightness

  • Gamma/Exposure - Apple Pencil's altitude angle along North/South controls exposure and the angle along West/East controls gamma

Gladman explains that "the app uses a spring loaded pattern, so the user needs to hold down one of the mode keys in the bottom left of the screen to stay in the filtering mode."

The source code for all three projects is available on GitHub.

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Top Rated Comments

FlexMonkey Avatar
123 months ago
I know this is sounds cool. But come on guys I'm tired of hearing this non-sense use of technology. There is abviously a much better device for such thing and it doesn't cost a lot of money to have one. I'm talking about the scale and somebody did it on iPhone 6S 3D Touch too. It's because you can it doesn't mean you have too.
Hi!

I'm actually the same guy that did the "Plum-O-Meter" for weighing things on an iPhone :)

Of course there are better devices, but I'm interested in experimenting, tinkering and playing then seeing what results. Actually, using the Pencil as a controller works really well for the fine adjustments in the image processing app and the fact the it has five degrees of freedom makes it a unique input device for the audio app.

Without some left field thinking, we'd all be using abacuses!

Cheers!

Simon
Score: 16 Votes (Like | Disagree)
Waxhead138 Avatar
123 months ago
Aren't the phrases "Highly Sensitive" and "Not Incredibly Accurate" a bad combination under pretty much any circumstance?

.....As a side note, those two phrases remind me of almost every girlfriend I've ever had, the first phrase typically causing the second.... ;)
Score: 7 Votes (Like | Disagree)
teslo Avatar
123 months ago
I know this is sounds cool. But come on guys I'm tired of hearing this non-sense use of technology. There is abviously a much better device for such thing and it doesn't cost a lot of money to have one. I'm talking about the scale and somebody did it on iPhone 6S 3D Touch too. It's because you can it doesn't mean you have too.
yeah, why would anyone ever want to do things?

i, for one, am witnessing exactly what i'd hope would start happening upon the release of a new device: tinkering, feedback, and constructive criticism. i'm sorry you're tired, i hear energy drinks are all the rage nowadays.
Score: 6 Votes (Like | Disagree)
Makosuke Avatar
123 months ago
Aren't the phrases "Highly Sensitive" and "Not Incredibly Accurate" a bad combination under pretty much any circumstance?
Nope, from a scientific terminology perspective, that actually makes perfect sense.

Accuracy, scientifically speaking, is how close to the real value a measurement will produce.

Precision (aka sensitivity) is how small of a quantity you can measure, accurately or otherwise.

And repeatability is how close to the same value taking the same measurement at two different times will produce, accurately, precisely, or otherwise.

So: An accurate scale will tell you something weighs 502 grams when it weighs 502 grams. A precise scale will tell you that something weighs 498.93 grams, although it might actually weigh 502.00 grams if the scale is not also accurate. And a repeatable (and precise) scale will tell you that something weighs 498.93 grams every time you weigh it, although if it's not also accurate it might really weigh 502 grams.

This particular "scale", silly or otherwise, will give you a lot of digits of precision on the weight measurement, so it's quite precise. It however isn't calibrated at all, so the accuracy is bad. No idea whether it's repeatable or not.
Score: 5 Votes (Like | Disagree)
nagromme Avatar
123 months ago
Think what you could do with 3 pencils! You could control that synthesizer with one, and jam the other 2 in your ears until the racket stops.
Score: 4 Votes (Like | Disagree)
joueboy Avatar
123 months ago
I know this is sounds cool. But come on guys I'm tired of hearing this non-sense use of technology. There is abviously a much better device for such thing and it doesn't cost a lot of money to have one. I'm talking about the scale and somebody did it on iPhone 6S 3D Touch too. It's because you can it doesn't mean you have too.
Score: 3 Votes (Like | Disagree)

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