PDA

View Full Version : Aperture Fan Cover



renaissance_modder
10-17-2005, 01:57 PM
Hello, long time lurker, first time poster. I'm relatively new to the modding scene, been lurking around forums like this one for a long time, but never done anything more severe than case painting. I must say that the work done by the members of this site is some of the best I've ever scene and I figure if anyone can help me become fully immersed in the modding scene it'll be this group. Okay enough with the brown nosing on to my question.

I would like to create an aperture style fan cover for the side panel of my case.

http://www.scphoto.com/assets/images/aperture.gif

I would like for it to open whenever the case is powered up and close again when it is powered off. Does anyone have any recommendations for materials to use to build something like this? How would you recommend automating it? Lastly does any one know where I might be able to find a diagram of the inner workings of an aperture? (I did a google search but couldn't find any images or docs that detail how they work the way the do.)

I appreciate any assitance anyone can offer thanks.

slaveofconvention
10-22-2005, 10:14 AM
Quite a challenge you've set yourself. I can't answer all of your questions, but I can give you some pointers.

How to open and close it - probably the best option will be to use a small servo motor similar to the ones used to control the steering on radio controlled cars.

How to make it open and close on startup and shutdown - On startup is pretty easy - you could use a relay to power the servo - using something like the power LED power to activate the servo - I'm not sure, however, how you could make it close again, although I suppose you could spring-load it or something so the power being on keeps it open and when the power goes off, the spring would close it - not sure what that'd do to the health of the servo though, it'd be constantly trying to open when the PC was on, and the springback would be forcing it to move without power.

As for the actual iris design, sorry, can't help at all there :(

Have a look at the Doom City project on here though - that has a door that opens on startup and closes on shutdown (if my memory serves)

snefan
10-24-2005, 03:36 PM
i've played with servo motors in school and having them trying to turn all the time will burn them out pretty fast.

turning them manually (or with a spring) shouldnt be a problem tho.

you have to come up with a way to make it turn then stop so you dont damage the servo.

crazybillybob
10-24-2005, 08:45 PM
I posted a Link to a USB to Servo controllor here but it got lost with the upgrade. So here it is again.

this is a link to Phidgets (http://www.phidgets.com/index.php?module=pncommerce&func=categoryview&CID=7&KID=) They have a Servo controllor that plugs into a USB port for about $28us, you can controll it with simple code and use it in a startup script or shutdown script to open and close when the pc boots.

Servo's are not motors, they work on Timed pulses, This way you can position it precisley every time. If you put stright DC on one it may twich but you'll burn it up after a short time!.

Here's a link for the shutters....their not cheap ($100+ us)
Edmund Optics (http://www.edmundoptics.com/onlinecatalog/DisplayProduct.cfm?productid=1373)


Good Luck!
Crazybillybob

Rankenphile
10-25-2005, 12:32 AM
Okay, I've been thinking about this one for a while, because I'm fascinated.

I came up with a VERY rough idea of how it MIGHT work, and drew it in about 30 seconds to basically describe the concept. Here's what I thought.

http://rankenphile.com/images/servo_diag1.jpg

If the servo were to turn the crank (circle bit) and push/pull the runners (top and bottom bit), which had small pole arms (blue bits) attached to the apperture shutters, you could conceiveably have them open and close. THis would take a TON of trial-and-error testing if I were to do it, and I would play around with lots of balsa/plastic sprue and a cardboard apperture before I attempted to build it, but theoretically, it SHOULD work, unless I am missing something.

Anyone else want to chime in and tell me why I'm wrong?

wingman358
10-25-2005, 01:58 AM
Alright, I was looking for some schematics on google, but didn't have any luck. I looked on eBay to see if there were any cheap apertures I could buy so I could investigate them. I gave up on that idea when I came across a picture which immediately illustrated the design. I've tried to simplify the design in the image I made below. Hope you can understand it (with my l33t MSpaint skillz)...

http://img500.imageshack.us/img500/4430/aperturenew9ki.png

Ascoates
10-25-2005, 08:55 AM
So from that diagram your saying it twists to the left and as it does twist the blades are pulled away?

Im using my limited knowledge to guess that the blades will obviously have to be hidden behind the case side panel.

If thats the case couldn't you use a small pully system for this to work, like i said I have limited to no knowledge about any of this stuff. Am probably just repeating what people have said in a really basic way.

Im guessing that the pullies could be thin metal rods of some sort.

Saying that if metal rods were to be used then there could be a problem with them getting in the way an making it look a mess.

Again from looking at the diagram the yellow dots in the blue and red ring allow for movement (again am thick :) )why would the red ring need to allow pivoting?

Unless the rings themselves actually twist around which I have just realised they do..

Im not to sure how this will work, wont there be strain on the pivot points.

Rankens idea seems like a good one, im guessin from his diagram that the top bars will move backwards pulling the bars up, whcih to me could me that they will have to possibly be some sort of pivoting allowed on the top bar to reduce any strain tht might be produced.

Anyway I think ive chatted rubbish now for long enough dont you :p

snefan
10-25-2005, 09:59 AM
I posted a Link to a USB to Servo controllor here but it got lost with the upgrade. So here it is again.

this is a link to Phidgets (http://www.phidgets.com/index.php?module=pncommerce&func=categoryview&CID=7&KID=) They have a Servo controllor that plugs into a USB port for about $28us, you can controll it with simple code and use it in a startup script or shutdown script to open and close when the pc boots.

Servo's are not motors, they work on Timed pulses, This way you can position it precisley every time. If you put stright DC on one it may twich but you'll burn it up after a short time!.

Here's a link for the shutters....their not cheap ($100+ us)
Edmund Optics (http://www.edmundoptics.com/onlinecatalog/DisplayProduct.cfm?productid=1373)


Good Luck!
Crazybillybob
yes i know they aint motors and work on timed pulses (1-2ms on then 10ms wait :p ), i just didnt know how to put it in english. soz :rolleyes: :)

also that usb controller is a good idea.

i asked my teacher and he said you can use the same port you would connect a printer on and just code some neat thing :)

btw whats the brown thing? it looks like a doughnut! :D

renaissance_modder
10-25-2005, 01:57 PM
Alright, I was looking for some schematics on google, but didn't have any luck. I looked on eBay to see if there were any cheap apertures I could buy so I could investigate them. I gave up on that idea when I came across a picture which immediately illustrated the design. I've tried to simplify the design in the image I made below. Hope you can understand it (with my l33t MSpaint skillz)...

http://img500.imageshack.us/img500/4430/aperturenew9ki.png

Thanks wingman this is exactly what I needed! Thanks to the posts that vanished after the upgrade I had pretty much determined how they worked and have been trying to work up a CAD drawing but I was having trouble getting it to line up and work correctly. Now I know why, my fin design was wrong. I plan to work something up in poster board and will post some pics on what I create soon.

Thanks for the feedback, everyone.

wingman358
10-25-2005, 04:18 PM
Thanks wingman this is exactly what I needed! Thanks to the posts that vanished after the upgrade I had pretty much determined how they worked and have been trying to work up a CAD drawing but I was having trouble getting it to line up and work correctly. Now I know why, my fin design was wrong. I plan to work something up in poster board and will post some pics on what I create soon.

Thanks for the feedback, everyone.

No problem, renaissance modder.

Just to let you know, the picture of the aperture blade in my previous post is from a camera. The blades in a camera aperture overlap each other (like so (http://static.howstuffworks.com/gif/camera2.jpg)). You would need to take that into consideration if you were going to be making your blades using that design.

Ascoates
10-28-2005, 12:12 PM
I just thought of summet, were all thinking about if the aperture has to be made.

Couldnt an old camera one be recycled with a small servo fitted to it?

Or would this be going bk to the burn out problem?