A DIY Book Scanner In Every Hackerspace /DIY Kit

[Misty]

This is GORGEOUS, Dan. Really fantastic. I'm looking forward to this.

As always, if there's some way I can help out.

[dtic]

This is so great. A lot of smart new design features. I do think a lot of hackerspaces (and others) will get one.

Have you tried some designs with the mechanical triggering automated (based on the book modules upward movement)? If so, what's your take on it?

I imagine that strain from pulling the handbrake is a bigger risk than strain from raising/lowering the module, given the neat counterbalancing. A challenge is to get a autotrigger to work reliably given that
1. different books differ in "height" (= thickness) and
2. the same book varies in "height" when you're scanning different parts of it.

Problem 1 seems easy to solve through a one time per book calibration of the trigger part. Problem 2 could be trickier. Maybe the platen could be made to move 1 cm upwards/downwards when pushed/not pushed by the manually lifted book module. That platen motion could be transferred to mechanical camera triggering. That could solve problem 2.

[rob]

Your cutouts only need the notches in one direction so that a square part will fit. This will give more bearing surface and make it a lot stronger..!

Nice catch -- there are a bunch of those double fillets in the file. When I create the 4'x4' files, I'll see if I can correct those. I kind of like corner fillets myself, but dogbones are fine.

--Rob

[jck57]

This is so great. A lot of smart new design features. I do think a lot of hackerspaces (and others) will get one.

Have you tried some designs with the mechanical triggering automated (based on the book modules upward movement)? If so, what's your take on it?

I imagine that strain from pulling the handbrake is a bigger risk than strain from raising/lowering the module, given the neat counterbalancing. A challenge is to get a autotrigger to work reliably given that
1. different books differ in "height" (= thickness) and
2. the same book varies in "height" when you're scanning different parts of it.

Problem 1 seems easy to solve through a one time per book calibration of the trigger part. Problem 2 could be trickier. Maybe the platen could be made to move 1 cm upwards/downwards when pushed/not pushed by the manually lifted book module. That platen motion could be transferred to mechanical camera triggering. That could solve problem 2.

You could have an over-travel mechanism that allows the pull down handle to go a bit farther down after the book hits the platen. There could be a spring loaded lever holding the handle that attaches to the pull-down crossbar. Cables from this linkage run to the shutter pressers. An over-travel trigger wouldn't care if the book was thick or thin. An added benefit is the over-travel spring will tend to limit the pressure on the platen. If you pull down till you hear or feel the click of the shutters you'll never pull too hard.

[jck57]

The economically functional focus of this design is ideal. The ingeniously elegant execution is a success, not because it's done but because it's in the place where the core idea is so solid, further revision will naturally evolve.

[daniel_reetz]

I made it to LA (my new temporary home) and I am going to spend some time answering questions today. Love the discussion going on here.

[GaryK]

.

[rob]

There's a bug in the fixture (yellow) part: one of the fixtures needs to be reflected vertically.

The part:

part.png (1.32 KiB) Viewed 1680 times

The fixture which needs to be reflected:

fixture.png (983 Bytes) Viewed 1680 times

[rob]

I noticed in your drawings that you have a 1/4" wide groove for the glass and it looks like it's only held in at the ends.
What's the story with this?

If I recall correctly, you put the glass in the grooves and then put a shim in to hold the glass in place. This way you can take the shim out, spread the glass out (to account for spiral-bound books) and reshim.

[rob]

I was also thinking about simplifying some of the design. Basically just leaving more material for strength. It will
probably be a little more stable when using it upside down for paperbacks. Keeping it from racking.

I think Corel Draw probably can't do Dog-Bone and T-Bone fillets. Of course, neither can Illustrator.