View Single Post
  #7   Spotlight this post!  
Unread 02-03-2015, 17:31
JABot67 JABot67 is offline
Unregistered User
AKA: John Bottenberg
FRC #2930 (Sonic Squirrels)
Team Role: Engineer
 
Join Date: Feb 2009
Rookie Year: 2007
Location: Redmond, WA
Posts: 328
JABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond reputeJABot67 has a reputation beyond repute
Re: Elevator Motion Profiling / PID Ramping

You could try:

- Open loop speed control on the elevator, such as connecting the Y axis of an operator joystick directly to the elevator motor output

- Closed loop speed control on the elevator (instead of position control), such as using the Y axis of an operator joystick as the setpoint to a (rate/speed control) PID controller which controls the motor

- Limiting the maximum output of the PID controller using SetOutputRange (float mimimumOutput, float maximumOutput)

- Motion profiling

Honestly, the open loop control might be enough. It's basically closed loop control given that the operator can look at the position of the elevator from the driver station to determine if it's moving too fast. If you are trying to do this in autonomous, though, obviously you have to use some sort of closed loop control. Limiting the maximum output of the PID controller may be a good idea in that case.
__________________
John Bottenberg - University of Michigan '14 - Microsoft
FLL Team "Dark Matter": 2003-2005
Robofest Team "Dark Matter": 2005-2008
Team 67 Programmer: 2007-2010
Team 3322 Programming Mentor: 2012-2014
Team 2930 Engineering Mentor: 2015-????