Firky

Lego Technic Grab / Claw / Gripper

45 posts in this topic

The mans a genius. I like this I'm glad I asked now :)

Thanks

Firky

Share this post


Link to post
Share on other sites

Sadly I don't have enough parts today to try the offsetting.

Lol what? :laugh:

Guys, do it like this:

*snip*

Also its a higher gear ratio this way.

Now that's genius, I've never worked with gears that aren't aligned along a 90° axis. Nice :thumbup:

Share this post


Link to post
Share on other sites

Lol what? :laugh:

Yh erm. My lego collection went from thousands of pieces to about 100 pieces.

Its on the up again now tho.

Share this post


Link to post
Share on other sites

Guys, do it like this:

28-8.png

Also its a higher gear ratio this way.

Hi zblj

This is looking good for a robot arm wrist joint, the 8 tooth pinion even fitted first time in LDD. I hope you do not mind I have added a possible up, down to the wrist. No linkage yet to opperate.

Wrist.lxf

Share this post


Link to post
Share on other sites

The 8t to 28t gear combination I found to be very useful when driving the old 28t differencials.

Share this post


Link to post
Share on other sites

All designes are welcome. I find that often my ideas need a bit of a push or I make things far to complicated and miss the obvious. I've never worked with 28 tooth before I didn't even see that lego turntable in LDD before I'm going to work on a smaller wrist design than I've used before trying to keep the weight down.

If you look on youtube for "firky2010" you will see my designs for a robotic arm.

Share this post


Link to post
Share on other sites

Here is a quick mock up of my current goal for the wrist. I used a similar set up with the larger turntables. But this time I'm trying to keep weight down and would like to put the motors in the forearm. So I need to route all drives from the wrist to the forearm

The next challenge will be getting the drive for the grab out of one side and the drive for the rotation out of the other.

mini Wrist idea.lxf

Share this post


Link to post
Share on other sites

Here is a video of the same design but fitted with a motor to reduce the amount of drives that need to be routed to the forearm. its by no means the final design but its a rough idea of what I'm trying to get to.

Thanks

Firky

Share this post


Link to post
Share on other sites

Looks good.:sweet:

Edited by Alasdair Ryan

Share this post


Link to post
Share on other sites

@ firky: Do you have all of the necessary parts to build it in real life?

Share this post


Link to post
Share on other sites

@ DLuders thanks for embedding the vid. I couldnt get it to work. Sadly not at the moment I will have order most of the parts in the video. I was also thinking about getting a L motor instead of the M motor. as it has far more fixing holes. also the 24 tooth black gear will be changed for a clutch gear.

I've also attached the design to this post.

mini Wrist idea 2.lxf

Share this post


Link to post
Share on other sites

I use yellow farm bricks. It may not be the cheapest. But every thing is well packed and the delivery is fast.

Share this post


Link to post
Share on other sites

I've done a similar design of spherical wrist, but using the big turntable as I don't own those small turntables (but I should definitely get some they look very useful!)

all the motor are attached outside the structure.

soon I will post some preliminary video of the whole 6 axis arm NXT controlled

Share this post


Link to post
Share on other sites

So guys my Lego pieces arrived today.

So I build up what I designed in LDD

5cdfb4af0aeb4e6882c4748e16377ab8.jpg

ed8596ad7907c965a25cebc5ba7b62aa.jpg

ea355084f72ace1266be2fe8c4642531.jpg

898a8d24f0ff6b6c6607d09ab22e53cb.jpg

There isn't enough room to use the clutch gear as I had planned so I think I'm going to use direct drive from the motor ( I can only hope this does not destroy the grab ). Only draw back to this is that the actual motor blocked the centre holes of both mini turn tables making it much harder to route the rotational drive to the forearm.

Thanks

Firky

Share this post


Link to post
Share on other sites

Do you think you could whip up a .lxf file for these claw designs? They look extremely promising!

EDIT: I was able to reverse-engineer the third claw from the photos posted. Here's my mockup in LDD:

0e1Fp.png

I colored the parts that wouldn't connect easily in bright colors. When assembling it in real life, all you have to do is connect those colors! I've included the original model and a design that I modified to attach an M-motor easily.

Download the .lxf here: https://dl.dropbox.com/u/84375076/firkygrabber.lxf [All credit goes to Firky for the original re-make!]

Edited by Phoxtane

Share this post


Link to post
Share on other sites

@Phoxtane Great job with LDD. I really need to learn how to use it. the mount for the M motor is good. But wouldn't suit the current needs when using a mini turn table.

Thanks

Firky

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.