Using those would make it quite top heavy though, moreso then it already is with his custom head. This is afterall, a BRAT, which is going to have a more limited payload then the heavier duty bipeds. IMO, stick with lighter custom arms as shown in the 3d design posted earlier.
Not the lexan, the servo’s. But whatever though…
Yeah two kinda big servo, that hads lots of weight, I think wowy’s post is ** sensible and could be ** helpful. I’m sure you could fugure out a way to make a hand with only one servo and that it could get a bette grip.
Yeah, what sam said. You could try modifying the gripper so that it only uses 1 servo, or try using Micros.
Tyberius is correct; the brat has a limited payload because of its inefficient design. The BRAT only has 3 DOF per leg, which means in order to shift the weight, the entire weight of the BRAT is all on one servo, which is the ankle servo. Because it only has 3DOF, the entire bot has to tilt with the ankle causing a rather large load at this joint.
The biped PETE has hip servos allowing the bot to shift its weight in the X direction where the torso remains level with the plane, while both feet remain planted on the ground. This is a much better way of shifting weight.
I might use little gripers and only have 3 DOF per arm. They will not be of much use but it will look nice. 8)
Sorry Mike, didn’t realise you weren’t gonna upgrade your BRAT to a Biped Pete, but sticking the with BRAT legs. My bad 
He isn’t. He’s building custom arms, it will still be a BRAT with upgraded servos and custom arms.
I do eventually plan to build a biped Pete. I already have the Lexan torso but I will need a few more parts.
For now the Brat is my main focus and I will add arms to it as well as PING sensors in the head. I want to experiment with the Brat platform before moving on to the Biped Pete so I can play around with autonomous control.
Eventually, I will get my sensor board working again and the SpeakJet taking, so when I am ready to make the transition, it will be ready.
I originally thought you would be ugrading to the Pete right away as I remebered from your original Biped/speakjet head project that you had a Biped Pete body. thought you were continuing with your original project. Agian, my mistake
Yeah, you’re right, my apologies for the confusion. I have been taking a lot of twists and turns on the direction I want to go. It was my plan at first to jump right in to the Pete version, but then I decided to take a few slower steps before diving right in to the bigger stuff. The Brat really is a great first biped and I’m not ready to give it up just yet.
The confusion is my fault. I can understand your confusion. 
Oh, don’t stop developing for the BRAT, Mike. There is much that can be done with it. I am watching what you do with The Bratinator very closely for future things I want to do.
8-Dale
Ok a Quick photo of what I have done. I have been rather busy lately and squeezing in Bot Building time is tough.
I have to bring in my dog to the vet tomorrow because dummy me tried to do my own grooming and managed to cut not only the hair but a chunk of skin right down to the muscle. Because I was pulling on the hair, it only cut the skin but it was all layers. Infact, you can see the thin membrane on top of the muscle. I could not believe I did that. I should have some time for a video tomorrow after the vet thing.
I have a sequence where the Bratinator is able to pick up an object on the ground and a few other sequences.
http://img175.imageshack.us/img175/2746/bratinatorzm5.jpg
And the injury I caused. My wife thinks this will heal and I tolder her there is no way in hell it will ever heal open like this. It needs to be stiched up closed. Right now you can move the hole around and inspect all the muscle. I am never going to do my own grooming ever after this.
Mike, I have never seen a better BRAT.
or a worse grooming job, hope the little guy’s not in too much pain 
LOL! yeah, word of advice, never rush a grooming job so that you can get back to bot building. 
Interesting idea! I mounted my “U” channel with the opening to the front of the BRAT instead of up. When I do arms for my BRAT, I am going to mount an ASB-18 coming off the “U” channel and mount an ASB-04 to the ASB-18 for the shoulder rotation.
I already have the pan/tilt head figured out and have the ASB-04 for the pan servo mounted. It will be mounted to an ASB-18 which is mounted to an ASB-06 that connects to the “U” channel. The head is up farther than I want it, but it was the only way I could get the pan servo mounted right. I’ll have a full 3D CAD model of what my BRAT will look like soon!
8-Dale
Here’s the video of the completed BRAT with arms. Although I am calling it finished, it’s really still a work in progress. I’m done with the chassis but there is always room for experimentation with sensors, software, etc… as far as adding more brackets or what not, there is no room left on this little guy.
You have without a doubt submitted the coolest BRAT video to date. Very impressive. I love to see what creations people dream up using my products. You sir, have made my day! 8) Thank you for posting the video!
Thanks Jim. It was a load of fun making. The arms work much better than expected. I was worried that it was going to make the brat have a difficult time walking but it really worked out very well. I did have to make him lean just a tad more to the left or right when taking steps, but not by to much. I’m happy with the performance over all.
WOW!! Looks great man!
Hi!
What can I say, VERY COOL! 8)
Awesome video!