11/11/10

Meeting Date: 
Thu, 11/11/2010
Start and End Time: 
10 am - 3 pm
Personnel Present: 
Alan
Personnel Present: 
Gavin
Tasks This Meeting: 

- Reset all the basic programs

- Fix the arms controls

- create an autonomous program

Reflections For This Meeting: 

Learning about PID's are fun... if you like math

In order to make the arms move to the right spots and stay there, we had to come up with a way to control them. Since the motors want to drift after telling them to stop (even if the right command is given in software), we figured that we'd have to come up with a method of controlling them based on the position (from the prototype board).

Although Karl spent a lot of time working on better bridge lowering design, I spent most of the time remembering PID.  We used it for line following for the last three years -- but now we are going to try it for position control.

 


Karl removed the temporary bridge arms we used at the qualifier and created these new 'hammers' to roll/push down the bridge for us to get our robot over it.

The 2 new roller hammers ready to be wired up.

Programming the new hammer positions.

Programming PID loops and tuning them is a lot of thinking. Its not easy to get them tuned either!

 

Our goal is to say "Get Middle"(using a subroutine) and the PID loops control the arm and shoulder to go to the right place right away.

Here's the white boards where we wrote out the calculations and the math that we used in the PID. Also the constants that we need for the positions are there too.

 PID is a  series of mathematical calculations. We determine Proportional, Integral and Derivative then add them together to come up with a value used to control the robot.  Kp, Ki and Kd are used to tune the PID controller