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DFZXA
05-03-2012, 13:02
I'd like to make a program that ignores extreme drops in voltage, but the way I'm thinking of it I would need to get the voltage at one time and get it at a different time in order to compare it. Is there a vi to do this or is there a simpler way.

Mark McLeod
05-03-2012, 13:16
There is a vi to grab the robot voltage on the WPI -> Driver Station pallete.

Ether
05-03-2012, 13:17
I'd like to make a program that ignores extreme drops in voltage, but the way I'm thinking of it I would need to get the voltage at one time and get it at a different time in order to compare it. Is there a vi to do this or is there a simpler way.

The simplest way to ignore voltage drops is to, well, ignore them.

But of course that's not what you meant.

I think you meant you want to compensate for changes in voltage.

For example, you want to maintain the same torque on a motor even if the available battery voltage fluctuates (due to other loads). If you are using Jaguars on a CAN network, you can do that using the Jag's built-in PID controller to control current to the motor. Motor current and motor output torque are very closely related so that would accomplish the task.

Or perhaps you want to maintain a steady speed, like the speed of a shooter wheel, even when the battery voltage fluctuates. This can be done by using a speed PID controller to control the motor's speed. If the battery voltage drops, the PID automatically increases the output PWM% as necessary to maintain the desired speed.

LabVIEW contains a PID vi. Check out the help.