BRAT + mini brackets =?

Sure, I’ll send the DXF files to you tonight. I’d love to get this to work.

Alrighty, added the brackets to the arms, and now it can get up! :smiley:

The sequence still needs to be tinkered with slightly, but here’s a quick video I shot:

youtube.com/watch?v=kO8xjKnfWA4
(my desk is a tad messy… Just focus on the robot… :blush:)

It may just be the serial cable, but it looks like the BRAT is having a hard time getting up.

No, look more closely. The left hand hits the ground when it’s moving to the robot’s back. Like I said, it still needs some work. It’ll get up just fine once I work the kinks out of it.

Looks Great! :smiley:

I totally agree! Great work James!!

Hi James,

Great work with the arms and the Visual SEQ sequence for the Brat. The mini brackets sure made Brat look cool. 8)

Grea work on the sequence moves. The arms work great.

Uhh… Thanks everyone :smiley:

Anyway, I’ve got a prototype for a micro-servo gripper set up. At the risk of sounding like a broken record, it needs some work, but I feel that this is (hopefully) a step in the right direction.

Fully open:

Fully closed:

Attached to the arm:

great work. you prototyped that quick!
having the access to you required parts and machines really pay off. :wink:

the gripper looks really cool.
once again cant wait for an other vid.

:stuck_out_tongue:

Looks great! If you want actual fingertips you can remove the last screw on the tips of each finger. Either way works. I was hoping to keep the bulkyness down but I guess that would make the arm to long I guess. If the gears are to loose that because I was not sure how it would cut using the laser, so I left a little play.

You work fast James! :open_mouth:

The main drawback inherent to the design is the pushrod must push the gripper closed. It would be better if the servo could pull the gripper closed, but there is no easy way to do that with the size and design of the gripper. Looks cool though. 8)

Good job! looks very professional. Can’t wait to see a video. How much weight do you think it could handle?

1, 2, 3…10 servos… :stuck_out_tongue:

What do you use to create the gears?

The laser has a kerf of 5 thou. So actually make them a little tight for a better fit. The assembly isn’t symmetrical, was that on purpose? Thanks for the file. :smiley:

Actually, there’s a total of 18 servos now! :open_mouth:

We’ve effectively just turned the 6 servo BRAT into an 18 servo monster :smiling_imp:
I’m eager to start testing it, since it’s been mostly building thus far. It’s using HS-425s in the legs, so it’ll be nice to see how quickly they fail. Who knows? Maybe they’ll surprise me.

Good idea, I’ll probably have to try that at some point now. The arm is actually not as large as I thought it would be. It’s only about 1/8" longer than the ASB-18 that I had on there before.

Haha, thanks 8)

Wha? You mean I have to shoot another video? I can prototype stuff, but I don’t know about videos… :laughing:

i know you cannot resist showing it off. :laughing:

will be interesting to see what becomes of this. finding out pros and cos of the whole design construct and seeing what works best for it will be very cool.

push it to the limits and see what happends. i dont think we should tackle stairs yet but could see how much It or He, (if you have named it) can LIFT! :wink:

My concearn was the roughness of the cut. I thought if I made it to tight the parts would grind. It makes sense that making them tight the laser would remove enough material providing the right amount of play. I wasn’t sure.

I used emachineshop for the overall design. The software has a very nice gear wizard. After I was finished, I imported it into Viacad 3D to make sure the dimensions are accurate like the ses bolt pattern for example, and then exported again using Viacad. Why? because I don’t know if I trust the accuracy of emachineshops export tools.

As for the symmetrical design, I purposely made the design slanted but I can make it symmetrical if needed.

James assembly looks realy cool. It kinda grows on you the more you look at it.

I started on another design last night to make the gripper close when the control horn is pulled instead of close when pushed. I can also make the frame straight instead of slanted if desired, and I have also made the gears mesh tighter to cut down on the slop. If there are any suggestions let me know.

I’ll have it finished tonight after work.

Ok I tried a few designs and this one will close when pulled and open when pushed. The extra gear makes things a little tight though. I’m not sure if there is enough room between the control horn and the ses bolt pattern. I know Jim used the word symetrical, but I cant help but curves in my design. Oh, and I made the gear mesh tighter.

http://img4.imageshack.us/img4/1830/microgripv2.gif

Input welcome. I’m not sure if I am taking this in the right direction or not.

Why not have it bent forward a bit more?

http://www.majhost.com/gallery/DarthToa/Robots/microgripv2.gif