Author Topic: Wiring Project [Updated Photos]  (Read 2512 times)

Armor Gnome

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Re: Requesting Help (small wiring project)
« Reply #15 on: August 21, 2012, 10:37:54 pm »
On the original cradle the four outer pins are raised to 'make' the gnd connection before the +'ve, as you have suggested AG should do.

Perhaps the pin floats on a convex bubble above its' contact, kind of like joystick D-pad or old keyboard?  If that is the case then it is achieving gnd first AND normally open functionality like I plan to do on the circuit, all at the pin level.  That is an great idea for me to add into my build.

My android phone *does* charge if I simply connect gnd and +5v.

I am no electronics expert by a long shot but I read a really good article on the way power to USB is handled.  There is a minimal amount of voltage available on the line (sorry I forget the exacts) until the device requests more power from the bus.  So the host does not power the USB port fully unless there is some logic at the connected device level to request it.  This is why when stealing power off a USB port you wire two pin feeds together (again forgot the specific colors but I believe its white and green) this gives you a closed connection which tells the bus something is attached and provides level 2 of its available 3 power levels to the 5v line.  I am guessing here because I don't have the article infront of me but it was something like: +1.5v constant, +3.5v when something contacts all pins, +5v when the device requests all available power.  This understanding was helpful when understanding how USB hubs function, because some devices ask for the power they need and others request full power as soon as attached.   
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phenigma

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Re: Requesting Help (small wiring project)
« Reply #16 on: August 21, 2012, 11:24:05 pm »
Perhaps the pin floats on a convex bubble above its' contact, kind of like joystick D-pad or old keyboard?  If that is the case then it is achieving gnd first AND normally open functionality like I plan to do on the circuit, all at the pin level.  That is an great idea for me to add into my build.

It's floating on a spring, or similar, and is not N/O, it is connected all the time.

J.

Armor Gnome

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Re: Requesting Help (small wiring project)
« Reply #17 on: August 22, 2012, 01:12:59 am »
Makes sense the more I think about it.  If all pins are rigid and hot, with a floating extended gnd, you would need the gnd always available for that pin.  It would then be first touched on insertion and last broken on device removal.  To add my switch idea I would need to make all pins floating and active, with my +ve rigid.  To really complicate things I could have all pins rigid hot, all gnd floating hot, and +ve shorter than the rest of the pins and floating N/O - solder the height difference onto the orbiter pads and I could assure +ve would be first to break on removal and last to connect on insertion.  Or all pins rigid, 4 +ve floating high N/O and 1 gnd floating high not switched. Gnd touches first, then all but +ve and then +ve switches closed, on removal +ve breaks first, then all but gnd, and last would be the 1 floating gnd.

How I finally wire it is going to depend on availability of floating pins.  If I locate 18 always active floating pins cheap then all I need to do is clip height on all but gnds.  If floating pins are hard to come by or expensive to buy each then I use rigid pins for 17 contacts and a floating pin for 1 gnd.  It may seem excessive but I still don't like the idea of +ve and gnd available for anything to cross or get bit by.  (I doubt many here realize it but I am in the occupational health & safety field)  It's only 12v but to me it's not quite right unless its disabled when not in use.

Here is my new current build idea

Quote
| |                                           | |         side view of the receiving portion of the dock
| |                                           | |                                
| |  [ ][][][ ]-[ ][][][ ]-[ ][][][ ]  | |         floating perforated board like vera riding on springs - showing the alignment pins non electrical which guide the webpad down
| |                                    i      | |         showing my one floating always on gnd pin "i"
| |     | | |       | | i         i | |      | |         showing my rigid pins, the "i" being +ve on N/O contact switches
| |     | | |       | | |        | | |      | |
                         |        |                       contact point for +ve

... I have way too much fun formating!  The only thing I couldn't show was the springs which would just guide the perforated board up and down.
« Last Edit: August 22, 2012, 01:36:37 am by Armor Gnome »
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phenigma

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Re: Requesting Help (small wiring project)
« Reply #18 on: August 22, 2012, 02:21:24 am »
You ARE having way too much fun!  ;-)  Let me know if there is anything else I can help with/provide.

J.

PS, keep having fun!

Armor Gnome

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Re: Wiring Project [Updated Photos]
« Reply #19 on: August 22, 2012, 09:29:48 pm »

  I have the webpad sitting in clay attempting to pull a mold for my pin guides and alignment posts.  While that sets I decided to scrap the old cradle design and came up with an all new one.  After building a basic 3 angle view I was able to take point measurements and count pixels to get my dimensions.  Would have been a lot easier if I used something other than GIMP but use what you have.

The basic shape is cut from stacked foam blocks and hand carved to my drawings.  Keep in mind everything is undersized in these photos so that when I go over the foam with clay I can add everywhere and get the geometry exact.  The design I am using is pretty basic but if the lines are not straight and angles don't match then I wasted my time and would have been better off sticking with the cigarette box. :)

The next set of photos for the cradle body should be clay, fired clay, mold, and then first pass attempt.  On the electronics side I am stalled for parts so it's likely I will have a color molded cradle with all my finishing touches waiting on guts.  The design is actually pretty universal and would work with slight modifications for ipad/iphone, nokia 800/900 and phone, etc.  Once the mold is made it really is no trouble to make small changes in opening sizes to fit other devices.  I just dremel away glass for bigger phones and add glass for smaller phones.  I love tinkering so as stated earlier no charge.  Linuxmcecompatible has this exact unit or message me about customizing something for a different device.  My own builds are simple based on broken-wallet-ness but I would love to get some of my ideas out of my head and into someone's living room.

Foam only - Devices resting comfortably

Fairly happy with the shape of the foam, keep in mind the final product is in places going to be 3/8 thicker.  The angle of the devices is almost perfect though and I was impressed by how well foam was able to keep a line.  Total measurements currently = 10.5" tall, 11.5" wide, 7" deep.  The orbiter sticks up about 0.5 inches above the backrest so its viewable area starts approximately 5.5" from the base and because of its lean back extends to about 10.5" from the base.  Configuration was set for desktop use next to a 22-25" monitor.  Depending on how you sit it should fall just below eye-level and just about perfect placement for button presses.

Empty Foam Template

This shot shows the angles of my design a little better.  You can also see the area I left myself for adding electronics, which will be critical when customizing these.  The relief cut into the backrest is for the external battery of the wedpad, it can get warm sometimes so I didn't want to box it in completely.  Even in foam the cradle is very stable, I have a slight lean back to my devices but they sit low enough to not cause an issue.  The base of the unit that houses the opening for a USB port will actually support an up to 3/4" wood bottom plate.  If it so much as wobbles after that I would shocked. 

Easy configuration options from here I may add to other pulls on this mold.  Adding an LCD alarm clock instead of a phone, adding a powered USB hub internally to make this a 4-port charging station for multiple users, adding an easy open back panel for hiding things such as chargers for rechargeable batteries, I would LOVE to get my hands on Squeezebox dimensions to put audio playback just below a full orbiter UI.  Of course I have my old crappy parts and weird projects that will find their way into these... integrated wireless AP, old receiver/amplifier parts to power audio from the core, add a chumby-sized orbiter below and a standard small LCD screen above from an embedded MD (no messing with touchscreen support, and keep full screen media with orbiter functions below, extend the base depth wise and add a compatible networked phone...

Finally, I haven't uploaded any of my finished model renderings because I have some little extras in mind that I would rather "Taaa Da!" than try to describe.   
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l3mce

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Re: Wiring Project [Updated Photos]
« Reply #20 on: August 23, 2012, 02:45:05 am »
Awesomesauce.

You make me want to make things again.
I never quit... I just ping out.

JaseP

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Re: Wiring Project [Updated Photos]
« Reply #21 on: August 23, 2012, 03:05:00 am »
He makes me want to spend money that I really shouldn't (and probably can't)  on a Makerbot or a Solidoodle...

And L3ME... You DO make things!!! ... Just sayin'

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Armor Gnome

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Re: Wiring Project [Updated Photos]
« Reply #22 on: August 23, 2012, 03:51:49 am »
... Well I hope it can be saved.  If not I have more foam and my dimensional drawings. 

Typically for something like I this I would finish off my wooden/foam/wire-mesh/whatever with DuraBond 90 in a few thin fast coats and be done with it.  I have worked with clay before but only for small parts where I shaped the part out of a solid block.  Using clay as a covering was an entirely different process that took me a while to get the hang of.  Instead of nice thin coats shaping sharp edges this wet clay I used actually worked best when applied an inch think and then dug back down to the shape I wanted.  I never did get the hang of a nice sharp line so deviated from my plans and added some slow curves.  - an hour later and it resembled a vase, an hour after that a standard fair clay pot.  Once I caught on to the idea of carving into excess clay for straight edges I was running out of steam.  Tomorrow I will decide if I like what I see, any chance anybody wants an ashtray/pot/vase?

l3mce - My classes are all on-line so combined with a LMCE hobby its pretty typical for me to have a string of bed-computerchair-bed days.  The day spent building something was a nice break that will let me get back to some template creation and C++ practice exorcises while I work on the wiring here at my desk/test bench.


I am aware that just because the device I am placing on top of this thing is supported under LMCE, this thread is not forum relevant.  Thank you for allowing me to post about it.  Because of feedback received I am going in a completely different direction electronically that without a doubt will make the difference between a working cradle and a pile of fiberglass and solder.
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