Have a look at this... its a good idea I think. http://m.instructables.com/id/How-to-make-a-robot-gripper/

What's it got to pick up? When you say cheap, how cheap? Bear in mind you will get what you pay for. You could build a gripper for the cost of a servo but it wouldn't be worth the cardboard it's made of.

@AAmeralis has posted his claw/arm design, it'll be worth having a look and possibly using some of his ideas. I think it's all covered in the original (huge) Lexi topic.

By cheap I mean the cost of the servo and then low cost materials used to make it.

@vhs896 I have seen this. Its a good idea but the size of it ruins it. It will be moderately sized. 3-6".

Aameralis, I guess more so i'm looking for ideas so what you come up with is good to post.

http://jjshortcut.wordpress.com/2010/04/19/my-mini-servo-grippers-and-completed-robotic-arm/

vhs896, this is actually pretty much what I wanted! Thanks! Although, I'm still open to suggestions.

lol, it's the stuff i have been looking at for ideas

http://www.thingiverse.com/thing:2414

http://www.thingiverse.com/thing:2433

http://www.thingiverse.com/thing:2415

There's lots of ways to make grippers and the material can vary from abs plastic , wood or even sheet metal. It's going to come down to what your comfortable working with as far as materials. Dont cheap out. You will probably spend 100 dollars on a well made gripper including the servos , wire , and materials used. If you are ok with 3d printing you can print one and add servos but it will still be a similar cost. The little things seem to add up.

Well, I found plans for an arm made of foam board(re-enforced) and I'm planning on doing a similar build to prannav's foam omnibot. So I was looking for an idea for the gripper so that the robot could pick up light-weight things. I didn't want to go and buy the 60 dollar grippers from ebay and the idea vhs896 gave me is basically the grippers on ebay but made of low cost durable material.

The most I have spent on any of my robots is well. Just on the ez-b and servos. The rest I like to use junk or free stuff. And I'm poor... lol

If you want it to work and look half decent I would take @aameralis up on his offer to knock up something for you and have it 3D printed. Or use it as a subject to get in to 3d cad and designing stuff for 3d printing.

To be honest, a lot (or probably all to be brutally honest) of the claw designs I've seen online are complete junk and not worth bothering with. If it needs to actually pick up something I don't think any of those linked to would do a satisfactory job.

Can we see some of the claws that you have made and tested? Like the ones that you say are junk? LoL after all. Its just bran storming here.

SMRT LoL smrt .... I have a crayon in my bran? LoL j/k

I made this gripper at a local fablab. Here's my result:

www.fablabamersfoort.nl/en/fabpublication/servo-claw

It only uses one servo and it's surprisingly effective at picking up objects.

That is sweet looking. I love it.

@Vhs like I said I'm only trying to brainstorm here. I haven't built any grippers yet.

@Niek, That's very interesting. I'm starting to make a mis-mash in my head of all these different claws.

@Rich, I would be tempted to use @Aameralis's offer but what I am attempting to do is make a gripper from basically junk. The gripper wont be picking up anything heavy. Maybe a pencil. Mainly for show but with the ability to do something. Looks aren't necessary, as I find that being able to see the way it works is fine.

@Aameralis, What I'm looking for is a claw with 2 or more movable fingers with a fair bit of surface area per finger. It would preferably run off of 1 servo to drive the fingers but can stretch that. Mainly, if there is any way it could be built using some material rather than 3d printing that would be awesome!

Thanks to all that have posted. If you have an idea or design that your willing to share feel free!

http://www.instructables.com/id/The-Junkclaw-A-junkclaw-made-out-of-junk-to-colle/

lol just somthing.....good idea... the junk bot. lol now my gears are turning......

homemade-terminator

incredible-diy-5-ton-megatron-robot

Sir Elton Junk

vhs, These are interesting sculptures. The 5 ton one especially.

That's what I thought too. Ideas can come from anywhere. If I can find the plans I have for this hand I made from bike chain and ruberbands and fishing line. I will post it.

sparkfun grippers

grippers

Thanks dude! These are interesting designs. Thinking of using all these designs to make my own gripper.

Heres my idea. Using part of the gripper design that's like the one in the shop, and the beetle like gripper rgordon posted I made this. Parts sized and everything. Comments? Changes? Also need to figure out what material to use.

Common guys! What do you think?

Aw dude! This is better, way better. Don't worry, I knew my design wasn't that original. Ill play with this idea. Thanks!

Here's my interpretation.

Huh? Huh? Yes I know the gear on one side needs to be offset a little so the teeth link up with the "fingers" straight. This was a quick job. ill do more to it to make it proper in a bit.

Techno pro. I think that looks good.there might be some play in the teeth of the gears. What about a mini servo for each claw. Or "finger". Its just a thought.

@vhs896, That would work but it's just as easy and cheaper do use the geared setup.

@Aameralis Thanks dude! Ill take a look. If you want, you could try do build the whole mechanism that I have shown.

So, what do you guys think I should make this out of?

Acrylic? A kind of wood?

Dj is making a bigger ez-bit gripper if you want to try that

I'm aware of that. Just thought I would finish this design in case I don't like the new gripper.

@Technopro Check this out micro_gripper_kit

You guys see this gripper on hackaday yesterday?

I'm very tempted to give it a try. I might be able to utilize an old hack I came up with or just use a chapstick or gluestick tube instead.

That could be modified to use the glue stick to pull the points of the fingers in or out. maybe not flexable fingers but still similar concept.