auto page turner prototype

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dtic
Posts: 464
Joined: 06 Mar 2010, 18:03

Re: auto page turner prototype

Post by dtic »

Thanks again, very cool but let's pause any parts sending for now. I really want to avoid branching out more right now and new parts also means new possibilities to think through... So for now my sole aim is to just get through the electronics steps as easily as possible. Then I can get back to the much more fun stuff: remaining mechanical parts, coding the Arduino and timing all actions.
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daniel_reetz
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Re: auto page turner prototype

Post by daniel_reetz »

OK. The rated drive voltages for the 2003/2004 are 5-30V; your 18V power supply falls neatly in the middle of that range. Your stepper, though small, could be geared/pulleyed to lift the platen. I think it's a good combination, though you'll probably want to stick a piece of metal on the top of the driver chip to keep it cool.
dtic
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Joined: 06 Mar 2010, 18:03

Re: auto page turner prototype

Post by dtic »

Ok have ordered both 2003/2004 chips now. I have counterweighted the platen and it needs little force to move so I'll test this setup first: stepper -- spool -- wire -- pulley -- platen. I'm a bit worried about the drawer slides jamming or at least giving irregular friction that will jam things or mess up the timings. Hard to tell before I test it.
dtic
Posts: 464
Joined: 06 Mar 2010, 18:03

Re: auto page turner prototype

Post by dtic »

I got around to this project again. I have the stepper working, with a spool added. But it can't handle the weight/friction involved in lifting the platen (even with counterweighting). The stepper frequently "stutters". I tried tweaking the spool, the rod etc but no go. As software autodewarping is improving so rapidly I'll pause on platens altogether and only aim for full "platenless" page turning automation.

(BTW, is there some handy way to temporarily but tightly connect a stepper cogwheel to a spool, rod etc? I've used epoxy and a custom drilled wooden plug for each test setup so far, which is cumbersome. I'd like some "universal adapter" that can quickly connect/disconnect stepper cogwheels and rods of various dimensions. Is there such a thing and does it have a technical term?)
(BTW2, if I'd keep working at platen automation then I'd try using an electric screwdriver as motor. Just a suggestion, if anyone reading this is going for platen automation.)

Going platenless opens up new possibilites. For example, might there be alternatives to using the V-shaped tray for the book?

I did a very quick test with book placed flat on its back. A stepper powered rod with wheels "drives" over the book until it is halted. In halted position the wheels instead moves the underlying book page i.e. turns the page and then rolls back to its starting point to the left of the book. The idea was fun and it worked pretty well when moving through the steps manually. But in the automated tests the jointed arms wobbled and got disaligned, which halted the rod. Maybe more rigid arms to hold the rod would help, but it looks tricky to solve. Another risk is that the rodwheel might crease the next page when rolling back to the left. So overall that setup isn't going to work I think.
rodwheel.jpg
rodwheel.jpg (117.27 KiB) Viewed 10202 times
So, I'm sticking to the previous system with an arm pulling the page to the left. But any suggestions on other platenless ways to automate page turning are very welcome.
sailor
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Joined: 04 Mar 2014, 00:53

Re: auto page turner prototype

Post by sailor »

Hello Everyone
I am new to the forum and new to the whole topic and try to read up on it before I might start a concept. Just 2 thoughts that came to mind while reading this thread:

Book cradle: I think it should be easily moving left to right to allow the platten to center the book freely. Low friction will be very important to be gentle to the book. To lock the cradle (after platten down / centered / scanned) one or two simple electro magnets with rubber tips mounted underneath would fix the cradle in position until pageturning is complete. They would released when the platten is half way down.

Sticky (double) page: would perhaps a videocam setup monitoring the process be a solution? Some kind of recognizing software looking for more than one line (page) in a frontal super high contrast view. There could be a short interruption between finger 1 and finger 2 action and if the camera senses an issue the process is halted and a alarm goes off.

Of course, everything totally theoretical from a total newbie.
dtic
Posts: 464
Joined: 06 Mar 2010, 18:03

Re: auto page turner prototype

Post by dtic »

Hi sailor and welcome,
Nice idea with the low friction moving cradle base plus magnets. The timed magnet lock means one more mechanical component to add though. I'm for now focusing on an automatic platenless scanner (and so need not worry about the cradle base) but I'm curious to see anyone else try it.
Re videocamera: that would need some really smart software and I'm not sure if there's any software close to that available. I think a better page pulling arm would solve any double page turning problems. After browsing a few robot gripper videos on youtube I note that many industrial heavy load robots have foam suction/vacuum grippers. I've searched but not found any miniature versions of those that would work well with arduino project. Say one with coin sized contact area and just enough suction to grab one sheet of paper. Maybe one of the usb vacuums for cleaning your computer keyboard could work? The suction needs only to be applied for a few seconds. Tubing would be easy I think. But I have no idea on where to find a very small foam suction part. Anyone heard of any part that could work?

BTW, here is one amazingly fast robot I came across. Look at it go! http://www.youtube.com/watch?v=0-Kpv-ZOcKY
Anonymous1

Re: auto page turner prototype

Post by Anonymous1 »

Heh, I think you might be getting another prototype. I've been working on a LEGO book scanner for a few weeks now (slowly; I have the cradle done), and the main reason was for page turning. Just to see if it works.
sailor
Posts: 3
Joined: 04 Mar 2014, 00:53

Re: auto page turner prototype

Post by sailor »

Hello dtic
Thanks for your welcome. There are some professional companies out there with all sizes of vacuum pods. The machine in your video uses one of the small ones..... the multiple page pickup is a real issue if you go vacuum: the vacuum can bleed through your page and create, together with the movement of the first page an area of low pressure that might lift the next page!

The video solution would not work reliably with this scenario. I don't have a solution for that (yet).

When using the foam "finger" the page get moved while applying some pressure to the underlying page. The finger should only move enough to create a bow and a second device goes into that space and makes the actual turn.
With this setup, a second page moved by accident, would most likly create a slightly different bow and a camera with very high contrast setting could detect that there is more than one curved line. I am not a programmer at all, but this kind of detection program should be reasonably creatable. Imagine the cars in the DARPA challenge have to see the street, obstacles, other cars, streetsign and much more......

It is interesting to think about solutions even if I can't find the time to tinker with the reality of it..... but I will continue to read and to participate once in a while here, when wI believe I have something meaningful to contribute.
TomHorsley
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Joined: 30 Jan 2011, 10:39

Re: auto page turner prototype

Post by TomHorsley »

I was wondering about auto page turning and am trying to decide if it might work better with an upside down platen using gravity to do some of the work. Shove the book up one side of the platen to make an opening for a roller or thumb, pull the page out enough to clear the top of the platen, and let it go, and presto, it falls down the other side of the platen.

No plans to implement this myself any time soon, just random brainstorming. I'm still waiting on my cameras so I can start on my first basic scanner once I convince myself the SDM software works with the cameras.
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