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General project discussion / help
Did you make a robotic coffee pot which implements HTCPCP and decafs unauthorized users? Show it off here!
By Valor958
#163976
I have several ideas for a computer case mod I am working on, and am trying to determine the feasability. Out of all the places I've visited, this seems to be the best resource for the level of customization I'm working in. Many case mods are very in depth, but I'm a bit different in the type of mod I'm doing. Many have said it's akin to 'putting the Batman suit on a computer', and I wouldn't say that's far off. I've browsed the internet for 3 years while I've developed this idea, and tried to squirrel away finances, and no one has done anything like this, so I'll reveal things as needed. I want to retain my idea before others copy it after.

One of the two ideas I have for a secure way to access my computer using biometrics is to hide away a fingerprint scanner. One idea was modifying a drive bay, which is fairly easy in the end, except for programming that scanner, but that's later. My idea here i'm working on is a push button roll top cover. Basically, I push a button, and a servo turns a cog with the roll top slats on it to roll it back, revealing the scanner, and possibly a near laser for flair. Again, that would be later after i get the basics functional.

For the roll top, my first idea was dissecting an old cd-drives motor and control and just reversing the controls. So, instead of the motor rolling out a drive when the button is pressed, it rolls back the slats. Like a roll top desk :)

Reading on here, it appears I might be better served getting the components from here and doing it myself. So, I would need a control board for the basic instruction set, a motor, basic wiring where needed, the cog attached to the motor, and track attached to slats.

How feasible does this seem? Compared to some projects, it seems fairly elementary, but it's all Greek to me, so I'm searching out help.

There would be low resistance on the track and I would use the best quality bearings on the track slide so as to not stress the motor. The slats shouldn't weigh much, but I don't have a weight yet. IF i can match the rest of my case, the slats will have a santoprene skin on them.
By Mee_n_Mac
#164108
No good ones.

When I envision a roll top, I don't see a servo having enough travel to roooooll. Instead I envision a cable (or 2) tied to the front and back of the visible slats. Hidden away, the cable is wound around a capstan which can be commanded to rotate both CW and CCW by a DC motor. It pulls the slats, from the back or front, into position. Limit switches tell the controller when to turn the H bridge off.

Some sort of drawing or even an animated GIF, with some dimensions, would help. I'm not "seeing it" in my minds eye.
By Valor958
#164151
Yeah, pardon my lack of proper terminology... I'm so new to this I'm relearning what proper names are and using general 'noob terminology' to describe actual parts. Servo was definitely not the right word lol.

The way you described it was basically how I see it. I'm working on a sketch in Sketchup Pro right now. I'm only using that since I already had a full model of my case, so it has all the work done for me already, except for my mods. I'm not sure I could do a rudimentary drawing in paint to really help 'see it' :\ But maybe I'll try. Problem being I don't know the right signs and such to show it off, but i'll give it the old college try :D

So, trying to talk more detail: Yes, a capstan or even just a gear set would work fine for that same design. I had an idea using the gear set from an old cd-drive, but i think it would end up more complicated than I need. Your idea using the capstan instead is what I'd originally envisioned, but didn't know how to work out. So, the cable would be attached to the slats themselves so when it moved CW or CCW the slats are pulled 'open' or 'closed'. The limit switches I also didn't know how to get put in place, so I need to figure that out as well.

Here are some 2D prints from Sketchup with some dimensions and notation. - I apologize for the huge pics, but spoiler tags don't work and can't get thumbnails working either :\ Not my night tonight lol

Image
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By Mee_n_Mac
#164194
Just to see if I'm on the same page ... I see a 139 x 128 mm that is the reading area. The AL slats cover that area when not in use and are dragged away and disappear under some cover. I've made An animated gif to illustrate the motion of the slats (red) coming out of hiding. The problem is to ensure equal pulls on both tracks (end of slats) so the slats don't jam.
(click on to open and animate)
rooltop.gif
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By Valor958
#164282
Yes, that's my basic idea right there. That top 139x128 area is the recessed top to a HAF932. In the pic below, I've highlighted the area fuscia for detail:
Image

So the slats would go inside, along the top of the case. So not quite at the right angle as shown, but probably almost an S shape. The slats would rest on a rail to be guided, and the pull cord (with teeth on it necessary to hold it in place) would rest on that rail.

So, what all do you think I would need to make it work? I'm no expert on programming, but i have a knack for it once I get into the flow of things. Logic based systems come fairly easily to me once I take time to examine them and work with them. It'll take me a good bit of time though, since this level of programming is like Greek to me atm.

Thanks for all the help, and any more to come! This is an idealized project for me and I would love to see it come to fruition.
By Mee_n_Mac
#164289
Can we assume the slats slide Left<->Right across the case top, covering the magenta area when closed and retracting into the case in the red outlined region (to left and vertically down) ? A lot depends on how much open volume there is in that region of the case. If all the slats were glued to a thin felt backing (w/little to no spacing btw the slats) you might get away by pushing/pulling them all from the center of the leftmost end slat.
(click on to open)
PCcasetop1.jpg
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