Shop OBEX P1 Docs P2 Docs Learn Events
Cutting Board Clock — Parallax Forums

Cutting Board Clock

JasonDorieJasonDorie Posts: 1,930
edited 2011-04-18 13:50 in Robotics
This is one that I've been working on for a while, but finally got around to putting some time into it (no pun intended).

The goal is to produce something that, when laid on its back, is a rounded but featureless white slab of cutting board plastic. When stood on edge, the display enables, showing the current time by lighting channels cut into the material from the inside. I'm pretty sensitive to light when trying to sleep, so I wanted something that would dim to almost nothing in darkness, but still be readable. I also wanted the numbers to fade instead of just changing, because that would be cool.

So far I have the front face and the LED board prototyped, and a rough draft of the control software running, including the ambient light detection.

I'm using Kye's DS1307 driver for the real time clock module, and a PASM driver I wrote for the pair of TLC-5940 LED dimmer chips (based largely on Brilldea's RGB painter code). The ambient light sensor is a green LED, wired backwards and using the RCTime code from the PEKit labs. The clock face and the LED driver board were cut using my home-built CNC router.

Photos are attached, and there's a short YouTube clip of it running. The video & pics of the display look really weird - in person the display is much "softer" looking, and doesn't have the strange halo effect present in the pics.

Video: http://www.youtube.com/watch?v=AuJiisMgn-A
IMG_7081.jpg
1024 x 765 - 67K
IMG_7079.jpg
1024 x 765 - 87K
IMG_7082.jpg
1024 x 765 - 92K
IMG_7083.jpg
1024 x 765 - 100K
IMG_7084.jpg
1024 x 765 - 153K

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-02-26 07:20
    Jason, what a cool idea! Those numerals are almost ghostly in appearance. I hope you'll be able to post a video of it in action when you're finished.

    -Phil
  • ctwardellctwardell Posts: 1,716
    edited 2011-02-26 07:30
    Jason, I really like that, neat idea.

    I've used a few cutting boards as material for robot parts, most of it machines very nicely with woodworking tools.

    C.W.
  • HumanoidoHumanoido Posts: 5,770
    edited 2011-02-28 03:52
    Jason, nice job! That's a very surrealistic display. I'm looking forward to seeing the final code and schematics.
  • JasonDorieJasonDorie Posts: 1,930
    edited 2011-02-28 14:06
    Thanks, guys. It actually turned out better than expected - I cut the PCB with my cnc router, but was expecting to make enough mistakes to have to do it again. Turns out I got it basically right the first time, even though this was my first board of any complexity.

    I think I want to try making the next one all SMT, and include the Prop, eeprom, regulators, and everything else all on one board, then have BatchPCB print them for me. I've soldered TSOP chips, but nothing smaller - I think it's about time I started.

    For this version, I have to make a schematic for the Prop side of things and tidy up the code a bit. I'm also having some issues tuning the brightness controls - The response of the RCTime function is non-linear, and I suspect that may also be the case for the LED and CDS cell I'm using, so I'm going to have to come up with something to map the output range of the RCTime function to a range of brightness values for the display. Once I have that a little more solid I'll try to post it all.
  • Matt GillilandMatt Gilliland Posts: 1,406
    edited 2011-03-26 14:38
    Jason- that's awesome! It's amazing what you can do with a cutting board :)

    Plus, in spite of erco's anti-plastic rants, you couldn't do that with plywood!
    - Matt
  • ercoerco Posts: 20,256
    edited 2011-03-26 16:03
    Heaven only knows what you polyethylene lovers could make out of THIS!
    http://cgi.ebay.com/Koku-All-in-One-Cutting-Board/270694029356?_trksid=p1468660.m2000037
    robochassis.jpg
    800 x 461 - 81K
  • JasonDorieJasonDorie Posts: 1,930
    edited 2011-03-27 00:37
    Matt - It is actually possible to do it out of wood, you just have to make sure that the lighting holes are cut very close to the front surface so the remaining material is thin enough for the light to shine through. I'm planning to do a smaller one that way.

    I finally got a function to map RCTime values to brightness in a way I like, so once I add daylight savings handling and the ability to set it I'll post an update.
  • ercoerco Posts: 20,256
    edited 2011-03-27 08:21
    JasonDorie, YOU DA MAN!

    Matt: Do you see? JD simply used polythylene as a first pass prototype, to hone his skills for the "real deal":

    WOOD! :)

    I'll have more words on the subject in a couple days.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-03-27 08:42
    Jason Dorie wrote:
    It is actually possible to do it out of wood, you just have to make sure that the lighting holes are cut very close to the front surface ...
    Or drill them all the way through and cover the front surface with a very thin veneer. The back part could still be plastic, and erco would be none the wiser! :)

    -Phil
  • ercoerco Posts: 20,256
    edited 2011-03-27 10:55
    PhiPi: Friend or Fiend? Only "time" will tell...
  • bennettdanbennettdan Posts: 614
    edited 2011-03-28 00:57
    Jason very nice I have seen a clock some time ago made with wood (link below) but I like Phil's idea also but either way it is a cool way to tell time.. maybe even a scrolling caller ID from your phone also..
    http://www.instructables.com/id/Solid-Wood-Digital-Clock/
  • ercoerco Posts: 20,256
    edited 2011-03-29 01:10
    Why settle for a clock OR a cutting board OR a robot when you can have all 3?
    robotclockcuttingboard2.jpg
    900 x 900 - 68K
  • Matt GillilandMatt Gilliland Posts: 1,406
    edited 2011-03-29 08:14
    @ Jason - awesomeness!

    @ Phil - always the prolific peace-maker, always the calming influence in a sea of erco's diatribes.

    @ erco - the jury has deliberated, argued, contemplated and came to their verdict...
    You sir have entirely too much cellulose in your veins - so much so, that I am vanquished. I lay my plastic sword down, and kneel before your plywood throne!
    -Matt
  • ercoerco Posts: 20,256
    edited 2011-03-29 08:33
    @Matt: No Sir! There is no win, there is no lose, there is no vanquish. Like Batman & Joker, you and I are destined to do this for all eternity here in Forum City. And like Harvey Dent, JasonDorie was my ace in the hole; his ingenious cutting board clock project has reignited my dastardly plywood plans.
  • Matt GillilandMatt Gilliland Posts: 1,406
    edited 2011-03-29 10:01
    @ Jason- again, well done!

    @ erco - Game-on, then sir! However, I must warn you that Phil is Forum-issioner Gordon, and together we shall spar with you well into eternity - well, maybe through the end of next week anyway.

    @ Jason too - if you do fall to erco's Dark side (plywood-atosis), there is hope. Yes, erco is lost, but there is antidote if you catch it early enough :-)

    touche'! swooosssh. (sound of *plastic* sword being put into scabbard)...
    -Matt
  • ercoerco Posts: 20,256
    edited 2011-03-29 13:30
    Better cellulose than cellulite. Touch
  • vaclav_salvaclav_sal Posts: 451
    edited 2011-04-18 11:40
    Little OT.

    Can someone please identify the actual chemical material of this cutting board?

    I am looking for lowest dissipation material in 10 to 30 MHz range.
    I have narrowed it down to Lexan ( Plexiglass) or LDPE (low density polyethylene).
    Ideally I would prefer just to buy the stuff about 1/2 inch thick.
    I think cutting board is too flimsy for my usage.


    Here is a link to some common plastics.
    http://members.tm.net/lapointe/Plastics.htm

    Sorry Erco, I cannot use wood - I am dealing with RF of several kV .This is not a typo - that is kilovolts for real.
    Vaclav
    .
  • PublisonPublison Posts: 12,366
    edited 2011-04-18 11:48
    Most cutting boards are made of HDPE (High Density Polyethylene). Some cheap ones, just out of PE (polyethylene)
  • JasonDorieJasonDorie Posts: 1,930
    edited 2011-04-18 11:51
    This particular material is HDPE (high density polyethylene) purchased from Tap Plastics in 3/4" sheets (they also have 1/2", 1/4", and 1" I think).
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-04-18 11:51
    Vaclav,

    How about starting a new thread for your question?

    -Phil

    Addendum: Oh, I see Jason answered, so I guess he doesn't mind the intrusion. Have you considered a composite, like linen/phenolic or glass/epoxy?
  • vaclav_salvaclav_sal Posts: 451
    edited 2011-04-18 12:11
    Thanks for reply. I checked Tap Plastic and they would sell 12''x12''x.5'' for $12 . That is resoanble.
  • JasonDorieJasonDorie Posts: 1,930
    edited 2011-04-18 12:11
    The thread veered off long ago with Erco and Matt. :) And no, I don't mind at all.
  • vaclav_salvaclav_sal Posts: 451
    edited 2011-04-18 12:20
    Still OT
    The fellow I am working with on the project - small transimtting loop antenna - did not recommned any material using epoxy. Too much RF losses.
    For what it's worth - neiter Plexiglass or polyethylene are UV resistant. But my atnenna projects usually do not last more than three years anyway.
    Just to be forum safe - the antenna will be remotely controlled ( tuning ) and rotation ( compass ) with BS2e.
    I am sure it will be a challenge to keep the BS RF safe.
    Vaclav
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2011-04-18 13:50
    vaclav_sal wrote:
    ... small transimtting loop antenna ...
    Okay, now you've really got my attention! This is something I've been wanting to try, too. Could you start a thread about this in the wireless section so we can discuss the design?

    Thanks,
    -Phil
Sign In or Register to comment.