Need to confirm

[umangv620]

Originally Posted by Alan Anderson

The appropriate answer to #2 is to mechanically support the arm so that gravity is not a large influence on its motion. Either a counterweight or some sort of spring arrangement would work. There is no easy way to deal with it in software, especially with a window motor.

For #3, setting the P constant too low will result in the motor being given so little power that it will stop long before it gets to the set point. The I constant can compensate for this, but it will take some time, and is likely to overshoot badly. What you generally want to do is increase P until you get oscillation, then back it down until you get reliable motion with a reasonably small steady-state error. Then increase I until that error is resolved with a minimum of time and overshoot.

If I use buttons and PID to move the arm to a certain position, will it prevent the arm from overshooting downwards? Lets say my arm is all the way up, and I want to put it to a 45 degree angle to drop it. If I use PID to move the motor until the certain voltage is hit (lets say 2.5 V), will it stop at the 45 degree angle, or does it still have the possibility to keep falling downwards due to gravity?