[Mad Scientist]After an endless amount of experimentation, we have finally managed to graft arms onto a BRAT! We are still in testing phases, and we haven’t managed to get a BRAT to accept fingers yet… But we are getting there! 
[/Mad Scientist]
Here’s some pics:
great. looks really good. its good to see the mirco brackets being used with the standard ones. this is a good way to show possible uses for them.
the pictures are really good. like the poses. 
cant wait for vid.
Finally! something that makes the BRAT more human-looking! This should be my next add-on for my BRAT.
Is that a Metal servo horn below the head?
Edit: Holy cow! 9 servos? that’s an awful lot.
Ahhhh! you beat me to it! I was going to replace my giant arms with micro brakets. I love the config you have. Perhaps Jim can cut lexan claws for the hands? I’m thinking 3 fingers. Two fingers with a thumb in the middle.
how about using the idea from Grant Imahara?
lynxmotion.com/images/jpg/morav02.jpg
youtube.com/watch?v=6O_0SmTp … r_embedded
I though about that as well… 
Yeah! This is looking awesome! The micro brakets are sweet! They open a lot of new possibilities!
Good work guys!
That BRAT is really growing on me. It’s pretty cool! 8) We are using HS-85MG servos on it. I’m thinking we will try the Castle Creations 10 amp BEC set for 6.0vdc and a light weight LiPo battery for the testing. I’m not sure how well the HS-85MG’s will be able to help in getting up, and stuff like that. Followers of this project thread be forewarned, this is uncharted territory. You might break a gear or something.
I keep looking at how he shoulder servos are attached and I cant seem to figure it out! How they are attached? Whats holding the three micro servos? ASB-18b?
First of all, let me mention that in order to do this and not have it look like a gorilla is to move the U channel back. This allows the shoulders to be directly in line with the legs.
I attached the shoulders (ASB-301) to the U channel with 3 washers between them to make room for the ASB-18 (the straight piece) so it could have a head. Which caused its own problems… 
So I had to use 2 washers there so it wouldn’t collide with the right shoulder’s bracket.
So, long story short? Patience. Lots of patience.
We’ll post a closeup image from the top.
Fantastic! I’ll be looking for that photo.
Oh, and you’re right, the brat does grow on you. I orginally wanted to build a biped pete style bot but the brat has kept me satisfied. This little guy is so expandable and very easy to work with.
We need micro Lexan hands to complete the arms, hint hint…
Yes, the smaller servo horn doesn’t fit the standard size SES pattern, so I swapped it for a full sized metal one.
Maybe so, but it’s worth it 
Alright… How about these?
That’s close to how I did my arms except that I had the channel bar with the opening facing out and used two ASB-18s to mount the asb-04s. Why not have the channel bar oriented this way, and take the micro ASB-04s (I don’t know the number) and mount them flat on top of the channel? Then you don’t have to use the washers. Unless there’s an issue with clearance, that might be a easier way. Access to the nuts are a little harder.
Here is the pic of the channel bar like I have it:
http://img245.imageshack.us/img245/1927/bratchassissq8.jpg
Thanks for those pictures!
I could do it that way, but then the battery would be sticking out the front end (I think it looks funky with a horizontal battery ) and I would still have to put spacers in there… The only upside would be slightly better weight distribution, so I may change it at some point, but it’s not worth the hassle at this point.
i really love that robot pretty amazing
I designed a possible gripper for the micro servo BRAT arms. I may need to move the control arm on the bottom finger more to the left, and I also still need to add an SES connection point to the wrist area. The image is more than double the size of the 1:1 scale gripper to show detail.
Here is what I have so far:
http://img529.imageshack.us/img529/2002/microgripper.gif
EDIT
Here’s version #2. I moved the servo horn left and made the connection point bigger. I also used the proper bolt pattern that the metal servo horns use.
Scale is 1:1
http://img162.imageshack.us/img162/4153/microgripper2.gif
nice idea. will you be making a working prototype?
this would make a nice addition to the ses range!
Thanks,
I was offering this as an idea for Jim to provide some sort if gripper design for the micro servo brat arms. Lexan is easy to cut using a laser cutter, and if your interested Jim, I’m will to provide you with the files to cut these parts to try out, or if want a completely new approach thats ok also. All the components are available on the shelf and the design is simple and easy.
Good news! The bot can do push-ups without frying servos and breaking gears! 
I wouldn’t recommend doing a whole lot of them, but when I was working on the sequence, I couldn’t help but imagine a smoking pile of HS-85s. So, in my books, this is good.
It can’t quite get up right now, since the arms are just a teeny bit too short. I’ll add an ASB-18 (the straight one) to the arms later and see how that goes. More pictures to follow 8)
Mike, feel free to send your hand drawings to me if you’d like. I could give that design a try.
