McKinley Robotics - Week 5 Blog

- Week 1 - Week 2 - Week 3 - Week 4 - Week 5 - Week 6 - Crunch Time - Hawaii Regional - World Championships - The Robot

Electrical Team Blog

[02/03/09] PID Control (Camera Turret)

posted Feb 4, 2009 4:48 PM

After simulation of the PID subVI, we've basically understand how this VI work. There are various controls and output that carry different functions. Before, we had a problem with the turret does not align and deadband of the turret is way too big ,but now we used PID to solve this problem, the turret will follow the camera servo, and as the turret reach the target the speed of the turret slows down which decrease the deadband of the turret, so the turret now aligned with the camera. We got it to work ,now we just have to play around with the constant values, proportion, time,and derivative time, to find the best value to make the turret to gain more accuracy and speed.

output range Control output is coerced to the range specified for output high and output low. Default range is -100 to 100.

	output high is the maximum value for controller output .
	output low is the minimum value of the controller output.

* This sets the maximum and minimum of the output for our program, In our case it should give out motor speeds -1 to 1.

setpoint The setpoint value of the process variable that is being controlled. This is the desired value for the process variable.

*For our program, the set point is the camera servo(converted to poteniometer's scale), so the turret will know the position of the camera.

process variable The measured value of the process variable that is being controlled. This is the feedback value of the feedback control loop.

*We used the potentiometer voltage values to check where the turret is.

PID gains Cluster of proportional gain, integral time, and derivative time parameters.

output The control output of the PID algorithm that is applied to the controlled process.

*This output connects to the set speed motor VI which controls the turret.

I was working the driver station.

On the FIRST website, it mentioned that the driver station is sensitive to electrostatic discharge

so, we have to do some rework. I connected the driver station’s internal ground with its metal housing to avoid

shorting other electronics. ( Detail see attachments)

Chen is indeed working hard on the program.

Same goes to fuquan and bryant.

In the meanwhile, the girls are wiring up the switches which have more steps since this year

we have to wire up a resistor between the power and the signal wire, to avoid floating pins.

Ms Owens is showing her master skills at wiring = ]

Disclaimer: These are actual student posts done by students and not paid actors. We make no claims or guarantees that the information contained herewith is 100% accurate or free of grammatical/spelling errors (English is not the first language for many of our members). You have been warned.