#robotics Logs

Jul 29 2020

07:25 AM Samian: 'd like to make a camera version of a scanner. So, you know how a scanner can create an image of a piece of paper it scans? I want that but for 3d stuff.. It's for food on a tray. I want to make a machine that's about the size of a drawer. I put the tray in the drawer and the machine scans a picture of the food on the tray.
07:31 AM Samian: Anyone know how to make such a machine? I was thinking having a series of cameras and using image stiching. But cameras too close to the thing they're taking a picture of causes blur.
07:35 AM Jak_o_Shadows: the approach of using a camera is called photogrammetry
07:35 AM Samian: k
07:36 AM Samian: that's good to know. It gives me a new word to google
07:36 AM Samian: slide in a tray. Press a button. An image of the tray is made. That's what I want
07:36 AM Samian: Is it possible ?
07:37 AM Samian: let me clarify. I'm not trying to make a 3d reconstruction. I 2d image output is what I want.
07:37 AM Samian: but I can't put a tray of food into a scanner. It's not a flat piece of paper. And food put on a scanner... just imagine the mess
07:38 AM ace4016: so you're trying to take a 2D photo/scan of a 3D object that can't sit in a flatbed?
07:38 AM Samian: yes
07:38 AM Jak_o_Shadows: What's the difference between what you want and a camera?
07:39 AM Samian: I don't think a camera can be that close to the object
07:39 AM ace4016: it can with the right lens
07:39 AM ace4016: and focus
07:39 AM Jak_o_Shadows: Or you could have it further away, and zoom
07:39 AM Samian: a tray of food is just an inch high. Imagine a slit where you can slide the tray in, press a button, and a 2d raster image is generated
07:40 AM ace4016: yup, camera with a wide angle or macro lense i believe can do it?
07:40 AM Samian: with a camera, you couldn't have a low profile I don't think. You'd need a tall with the camera mounted at the top pointing down
07:40 AM Samian: macro lens!!!!
07:40 AM Samian: thanks!!!!!!!
07:40 AM Samian: https://www.adorama.com/alc/wp-content/uploads/2017/02/shutterstock_141034498-1024x682.jpg <--- bingo!!
07:41 AM Samian: see how close the cmaera is to the object it's taking a pic of!
07:41 AM Samian: yessss
07:41 AM Samian: thank you ace4016!
07:41 AM ace4016: glad i was of some assistance :P
07:41 AM Samian: So I'll buy a series of cameras with macro lenses and do image stitching!!!!
07:46 AM ace4016: there are some mirror tricks you can use as well if you want to a lowish profile and only one camera
07:56 AM Samian: ace4016 it seems that macro lenses by their nature are pretty big, not super thin like this: https://4.img-dpreview.com/files/p/E~TC4x3S590x0~articles/7077967600/Apple_iPhone-11-Pro_Matte-Glass-Back_091019.jpeg
07:57 AM ace4016: correct
07:57 AM Samian: crap, macro lenses are expensive too. I was they'd sell for no more than $40 bucks a lense
07:58 AM Samian: hmm. I guess I could go for 1 lense/camera and rotate the tray. have a spinner to sit the tray on
08:00 AM Samian: actually, on amazon I'm seeing cheap macro lenses you can clip to iphone cameras.
08:00 AM Samian: that's sort of what I need. a small camera like the iphone camera, and a small macro lense
08:02 AM ace4016: moving the camera means you can use one camera too
08:02 AM ace4016: and it might be easier to move a small camera rather than a tray
08:02 AM Samian: ace4016, yeah but I'd need an x/y gantry system
08:02 AM Samian: right?
08:02 AM Samian: gantry systems aren't cheap I don't think
08:03 AM ace4016: also, planetary scanners exists; SpeedEvil linked you one on amazon :P
08:03 AM ace4016: (in electronics)
04:39 PM Tom_itx is now known as Tom_L
07:00 PM sinned69154 is now known as sinned6915
11:13 PM gaze__: hey suppose I have two rooms, a room full of noisy equipment and another that's pretty quiet
11:14 PM gaze__: and I wanna pass some very thick cables from one room to the other
11:14 PM gaze__: and I don't really know what kinds of cables I'll be using up front... so I can't really make a panel full of bulkheads and seal it.
11:14 PM gaze__: any ideas what I might use to seal the noise off?
11:15 PM gaze__: I was thinking a bristle seal maybe?