B.R.A.T Question

I am also using 475HB servo’s,and they can barely hold it up.

I kind of halfway remembered having one of those 5-cell packs around here, and sure enough, I did.

Tossing them on the scale, it says that…]The 5-cell sub-C pack weighs in at 9.4 ounces (267 grams)/:m]
]The 6-cell 2/3-AA pack weighs in at 5.0 ounces (143 grams)/:m]That’s a difference of just 4.4 ounces (124 grams) - or 22 US quarters - not a tremendous difference, but it might be enough to cause problems if your bot really is on the borderline of functionality.
[EDIT: depending on the servos you are using, the increased voltage of one additional cell may improve the available torque enough to make a noticeable difference, too.]

My 6-cell pack is just a cheapie that I picked up at a local hobby shop. I think it’s a standard size used in the mini trucks and such, since there was a fairly good selection of packs in this form-factor. I didn’t go for fancy or expensive - I just wanted cheap volts, and it’s worked great for me ever since.

Here is some quick photo’s i took of the battery pack,Notice how it is sandwiched in between the Bracket :
http://i122.photobucket.com/albums/o255/wowy5/IMG_5109.jpg
http://i122.photobucket.com/albums/o255/wowy5/IMG_5108.jpg
http://i122.photobucket.com/albums/o255/wowy5/IMG_5106.jpg
http://i122.photobucket.com/albums/o255/wowy5/IMG_5105.jpg
http://i122.photobucket.com/albums/o255/wowy5/IMG_5104.jpg

The 475’s work well at 6.0vdc. I never run them at 7.2vdc because they become a bit hyper and jittery. The BRAT should work ok with that pack, but if you plan to add additional electronics, cameras, sensors, etc. Then I would recomend switching to a 5 cell AA pack. Looks nice though…

Ok,as long as it works.

Oh another question,Is there any BRAT sequences for the SEQ avalible?
because I’m not good at using the Sequencer yet,so i need something to test the BRAT with to see if it can Walk.

On the Information page, under the heading of bipeds], there is a BRAT assembly guide. Directly under that, there is a link to a tutorial for using SEQ with the SSC-32 to control a BRAT. The sixth line of text in the tutorial is a link to a ZIP file with a number of pre-built functions. (under the lines that read: “Software:” and “BRAT projects”, with an arrow pointing at the link.)

I looked at these, and they gave me an idea of some of the motions I would be going through to perform the various functions, but I found it more educational to just build my own sequences using the pre-built ones as guides, rather than modifying them.

Thank’s fot he Help Seamus,But i tried the sequence where the BRAT is supposed to kick,and it kicked backwards,I have a Video Here :
i122.photobucket.com/albums/o255/wowy5/th_100_0163.jpg

Yeah, my servo offsets were far enough off that I didn’t have much luck with using the “canned” sequences as-is. That’s what I meant by it being more educational to use those as a basis for building my own sequences - by looking at the steps that were being performed, and in what order, I got a feel for how to go about achieving the desired result, and then built my own sequences with the correct offsets, directions, etc. for my bot.

I much prefer to learn how it works and then apply that knowledge than to just use a series of pre-canned moves, anyway. If that was all I wanted to do, I may as well have just bought a toy off the shelf.

Well the point is that i wanted to test it because i am still learning how to use the sequencer,not to spend two months learning how to use it.

For testing purposes, it looks like you’ve got the axes working properly, as they all appear to be responding to the movement commands.

For learning the program, nothing beats sitting down with the documentation and tutorials. That’s what they are there for - to document and tutor. Read them, work with the program, and you’ll soon figure out what does what, and how the controls translate to your bot’s motions. It won’t take weeks; if you read the supplied materials, you could be easily be creating your own sequences within an hour or two - quite possibly a lot less than that.

Ok,Thank’s,It looks like I’m going to be making my own Sequences :slight_smile:

Ok,I’ve made my own Sequence,its not the Great but it gets the job done :
i122.photobucket.com/albums/o255/wowy5/th_100_0164.jpg

You need better lighting when you are making a movie. A black BRAT in a dark setting does not show up well at all.

8-Dale

…and here I was thinking that the first one was hard to see.

Yes, lighting is a good thing when taking pictures, and especially important for video.

I’ll second the call for better lighting; we can’t offer input if we can’t see what you’re trying to show us.

Huh,Thats Weird,I had the lights on when i recorded,i guess I’m going to have to make a new video when its light out tomorrow.

Ok,I got the new Video,ts going to take a little while to upload though. I will notify you guys when its done.
I need a Bigger Table :open_mouth:

Here they are :
i122.photobucket.com/albums/o255/wowy5/th_100_0169-1.jpg

the robot seems to be sliding rather than picking up his legs and moving forward. :laughing:

LOL,thats because i need a bigger table,If it took Steps then i would’ve made a return for my BRAT by now :laughing: