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#1  
Hi rich. The format that ezb uses to control servos and digital inputs are the same as rc rx. May I ask what you are using the gyro for? Not all gyro are created equal and some have drift and jitter. These are terms to describe when a gyro doesn't think the object is moving but it slowly drifting in one direction. That is not correctable and has to do with the quality and accuracy of a gyro.
#2  
My idea is to create a one wheeled robot. In all honesty, now that I see the image, I want to end up with a robot similar to the one beside your "we have tutorials" logo. A little more horizontal than vertical though.
#3  
Ok you need a very sensitive gyro. My favorite and one of the most accurate gyros under 100 dollar's is the futuba gy401 . http://www.ebay.com/itm/Futaba-GY401-Heading-Hold-Gyro-250-450-500-550-600-700-/280910967260?pt=US_Character_Radio_Control_Toys&hash=item41679931dc

You will need two, one for x axis other for your y axis. The purpose of the gyro is to use accelerometer feedback to actively adjust the servo input to stay balanced. This also gives you manual adjustments directly on the gyro itself and because it has a "heading lock" feature it can compensate for forward movement and still stay level. I know these arent cheap but your better off than buying a digital output ic2 board and the accelerometer freaking out as soon as the robot is moving in forward motion. These gyros sample position 2048 times per second. One end of the gyro y harness plugs into ezb and the other your servo or h bridge being used to drive your balance bots wheels. You will need to use external power unless your drive wheels you standard rated servos. More amperage is pulled through a servo or motor that is constantly adjusting and ramping the wheel position back and forth.
PRO
Synthiam
#4  
You could also use a Wii remote:) but it won't be very sensitive. It'll actually be quite funny lol
#6  
Ok, thanks.

One last question, is there anyway, you know of, for me to not only balance the bot on one wheel but also drive it?
#7  
Oh and I plan on using the wii remote
#8  
Drive it? Ive never seen it really driven so I will check setups of other uniball bots.... brb
#9  
When you said you plan to use wiimote did you mean as the gyro or as a controller? After I looked st this on paper if using the gyros I mentioned you should be able to drive it easily .... not too fast though:)
#10  
As a controller... I was thinking I could use the remote to "input a value" that would over come the gyro...to allow both steering, if x, and motion, if y.
#11  
@CRich yes once the gyro is calibrated the bot will fight to stay level until it gets a servo input and it will start moving that direction. Using a wii mote would be cool though. Show it off to your friends. Maybe make a maze and get your friends to try and navigate uniball bot through the maze lol.
#12  
Haha, alright. I'll put up some pics when it's done
#13  
@jstarne1
I've got two of the gyros on the wat!
You said you drew it out, does that mean a schematic? Being that this is my first solo build, is there any chance you would share that me?
#14  
Humm, found this thread :-) and was thinking about adding a gyro or two to my biped.
So I started experimenting with a GWS PG-03 I had laying from heli stuff. If for example, I put the gyro in series with one of the hip servos, the idea is when bot falls forward hip rotates back to keep CG (upper torso) in line. Seems to work for that side, but what about the other hip servo?

I thought about making one a slave to the other in EZB, but since the gyro feeback is outside of the EZB control, the second / slave servo is unaware of the correction, since it does not get a position feedback from the master.

Do I really need a gyro on each hip and keep them independant or is there away to do this in EZB?

Perhpas put the gyro on a seperate digital port and read in the values, than some how feed that as a corrective action to the servo pair?

TIA for any pointer.

jimk
#15  
I guess I should follow DJ's lead & go order a MMA7455 I2C device, and be patient for it to arrive.
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