Just started: Fraction Cracker - measurements conversion tool

[vik_fc]

Hello everyone,

Yesterday I'm started Kickstarter campaign:
https://www.kickstarter.com/projects/angelinvent/fraction-cracker-advanced-measurements-conversion-tool

It's allows you convert fractions in their decimals; feet and inches to meters and millimeters as well with only two knobs.





Any feedback and suggestions would be greatly appreciated.

Thank you.

[ivaylo]

Solving fractions is nice, but it would be a really powerful tool and you could probably charge more if it did:

• thousands of an inch math and metric conversions (important for this forum)
• data entry in metric (got the impression it’s imperial only now)
• other units, not only length
• allows for firmware updates (couldn’t tell)

Otherwise your goal seems a bit high, hope you hit it. Good luck!

[vik_fc]

Thank you ivaylo.

Correct, imperial system is main for Fraction Cracker.

thousands of an inch math and metric conversions (important for this forum)
data entry in metric (got the impression it’s imperial only now)
other units, not only length
allows for firmware updates (couldn’t tell)

Yes, conversion metric to mils (and vice versa) is good idea, thanks. Same about metric data entry.
I thought to add other units, such as weight - this may be useful.

About updates - I'm not sure, because it will increase complexity for end user (I want to keep it simple as possible).

[vk6zgo]

Sorry, it might have become a big seller in 1969, but its time had passed!

You can pick up pocket calculators secondhand at swapmeets which do that & more, or have a "App"on a smartphone.
I can't see why only two knobs is a big selling point, unless you need to use it wearing heavy gloves.

[vik_fc]

Big seller in 1969? Based on transistors and core rope memory or what?   
And there's no app or calculator on the market with similar input interface...

[vk6zgo]

Big seller in 1969? Based on transistors and core rope memory or what?   

Read this & weep!
http://www.vintagecalculators.com/html/history_of_electronic_calculators.html

And there's no app or calculator on the market with similar input interface...

Perhaps there is a reason for this...

[jpanhalt]

1) None of the "Play" video buttons work in your link.

2) Going from fraction to decimal is simple.  Any calculator does that.  The example implies your device can also go from decimal to fraction.  Is that true?  What granularity?   For example, can you enter "0.081300813" and get the correct fraction or series of fractions?

3) As one who has worked with fractions and the imperial system for a long time, I can tell you that many times, an odd fraction, say 35/64 is represented as 1/2 + 3/64 or even 1/2 + 1/32 + 1/64 and so forth.   I believe that system dates way back in time.   It is convenient for the worker, because the measuring device being used may only be divided to 1/16ths or 1/32nds.  So, a pretty good estimate can be made.  Can your device do that?

[bitwelder]

A proposal for the Mk2 version:
- incorporate the sensor from e.g. a laser meter so that it's possible to input directly lengths.

[vik_fc]

1) None of the "Play" video buttons work in your link.

Looks like it was some troubles on Kickstarter. Now it's working.

2) Going from fraction to decimal is simple.  Any calculator does that.  The example implies your device can also go from decimal to fraction.  Is that true?  What granularity?   For example, can you enter "0.081300813" and get the correct fraction or series of fractions?

Yes, you can. The question is how fast and simple it will be.
Minimum granularity (or count step) equal 0.015625" which is 1/64". You also can choose 1/8 (0.125), 1/16 (0.0625) or 1/32 (0.03125) steps.
Every time, when fraction (-s) are changed, also is updating number of feet/inches (first row), decimal part of fraction (second), fractions itself (middle), meters (fourth) and millimeters (the last one).

3) As one who has worked with fractions and the imperial system for a long time, I can tell you that many times, an odd fraction, say 35/64 is represented as 1/2 + 3/64

You can always scroll one or two steps up/down and get closest eighth or sixteenth fraction.  How it works:

- incorporate the sensor from e.g. a laser meter so that it's possible to input directly lengths.

I agree with that.

[PlainName]

Cool bit of kit, this. I just can't think of an actual use for it, so for me it would be shelfware after exhausting the job distraction abilities of it.

What would be excellent (though, sadly, not enough on its own to warrant a play with this) would be imperial decimal to imperial units conversion. By that I refer to, for instance, weighing scales (or apps) that 'do' metric or Imperial, but the Imperial is invariably like "10.3 st" rather than the proper "10st 4lb".

[mariush]

I don't like the way it looks.

It's too thick (hard to put in a pocket to carry around) and too wide - i get it that you want to use two fingers to spin those wheels but still.
It's not like it can stay on the desk like that, you have to lift it to move those wheels around and when you're on your feet at a desk you'd probably want to lay the thing flat so that the screen points up.
Are those wheels tactile, do you feel some resistance when advancing a 1/8th? Some click, audible feedback etc ? How well do those work with gloves on? How about dust going into the device ?

A multimeter or phone style format would seem to make more sense and maybe you'd be able to use just 4 buttons and a mode / set button to keep costs lower ...  < ... >   mode   < .... >  or a couple dpads  ( left - right changes value, up down changes measurement unit, middle = reset )
ex https://www.digikey.com/product-detail/en/panasonic-electronic-components/EVQ-Q3AA15/P12330SCT-ND/593493

with a more phone/multimeter style look, maybe you could design  ruler on the edge or something like that and have a second purpose, or maybe have a measuring tape come out from the edge

With a 16:9 format, you could squeeze a 320x240 oled or even higher resolution lcd monitor and have bigger text


As is, the box is big enough you'd easily fit buttons ...  the classic  0  to 9 and a dot and 2-3 other buttons would be enough.
push button for first number , push button for 2nd number  ... use dot to go between the parts of the number  ex type  1.1.16  to enter 1 1/16  or  ..4 to change the 1 1/16 to 1 1/4

Guaranteed it would be faster than moving that wheel with super fine control and double checking yourself when you see those fractions change.

Look at your keyboard numeric pad ... have all the things you need there... 0..9 , +,- , * , / ,  num lock can become select number (first or second) ... people are used to that layout.

Less moving parts, cheaper, microcontroller can start up on keypress and less accidental turn on in your pocket or less damage prone if you bump into something while the thing is on your waist depending on button size and spacing you can press them with gloves, you can make a small sound when pressing the buttons for feedback...

add a white led and some lens at the top and use it as flashlight... you could replace the single aa with 2 AAA rechargeable or a flat lithium that can be recharged through usb once every 2 weeks or a month ... ex https://www.digikey.com/product-detail/en/adafruit-industries-llc/2011/1528-1857-ND/6612469

Looks like it will break in pieces if it falls off a desk on hard cement... how it handles actual construction jobs.  Think rubber corners or something, or add metal inserts for screws on the case.

[free_electron]

i want a mode where i can LOCK the BASE fraction.

Now as you dial it goes 31/64 -> 1/2 -> 33/64. i want to be able to tell it : stay in 64ths and show it as 32/64. or stay in 16ths. or stay in 32nds . It should autolock to the smallest fraction given in a number.
if one is given in 64ths , the other should lock in 64ths as well. The result can scale. but the entry should not. ( or have the option to lock both entry and result , or show result in same fractions as entry , and scaled version. you have a graphical display. should be possible.