BEI Gyro Accuracy

[John Gutmann]

As an update: Mostly to you billbo911

I realized I had no "base" code to even drive the bot around, so I decided to work on that first. I am doing the 2 drive motors off of the 16 bit Timer1. Timer0 I decided to make an "event" timer. This way I can say do this after x seconds, or whatever and it will be very easy to do. The resolution is .01 seconds, which should be fine for my needs. The accuracy should be 0.0128% assuming the internal clock has 0% error (pffft! yea right!) and not counting any latency. But this should all be fine for this application. I wrote some simple motor functions to stop, both, stop individually, and set the speeds either together or individually.

I mounted my bread board to the top of the bot, it is a very nice set-up now.

The only problem I am having is that with how the motors are on there, one is turning CW while the other is turning CCW to go forward. So it curves. To solve this, I think I am gonna try to somehow mount the motors both facing the same direction. This should solve the problem.

I can share the plans of the bot and my code if you would like. I assume you can almost just use it with little to no modification from what I have.

-John

[billbo911]

Originally Posted by John Gutmann

As an update: Mostly to you billbo911

I realized I had no "base" code to even drive the bot around, so I decided to work on that first. I am doing the 2 drive motors off of the 16 bit Timer1. Timer0 I decided to make an "event" timer. This way I can say do this after x seconds, or whatever and it will be very easy to do. The resolution is .01 seconds, which should be fine for my needs. The accuracy should be 0.0128% assuming the internal clock has 0% error (pffft! yea right!) and not counting any latency. But this should all be fine for this application. I wrote some simple motor functions to stop, both, stop individually, and set the speeds either together or individually.

I mounted my bread board to the top of the bot, it is a very nice set-up now.

The only problem I am having is that with how the motors are on there, one is turning CW while the other is turning CCW to go forward. So it curves. To solve this, I think I am gonna try to somehow mount the motors both facing the same direction. This should solve the problem.

I can share the plans of the bot and my code if you would like. I assume you can almost just use it with little to no modification from what I have.

-John

Anything you would like to post up would be great. I'm sure I am not the only one who might benefit from it.

My ultimate goal is to use the Arduino, or some other variant of the ATMega chips, to build a single board to both read in two+ quadrature encoders and a gyro and be able to provide distance and orientation from a single serial stream. I might use I2C but I will definitely have a simple RX/TX source.

BTW, as a test, I have removed the guts from a ball mouse and will be using this as a source for a test set of Quadrature encoders. Hey, it was cheap at $5 for a pair of quad's. Now I just need to interface them mechanically.