Thread: Shooter Lag
View Single Post
  #6   Spotlight this post!  
Unread 16-01-2012, 11:00
Kevin Sevcik's Avatar
Kevin Sevcik Kevin Sevcik is offline
(Insert witty comment here)
FRC #0057 (The Leopards)
Team Role: Mentor
 
Join Date: Jun 2001
Rookie Year: 1998
Location: Houston, Texas
Posts: 3,717
Kevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond reputeKevin Sevcik has a reputation beyond repute
Send a message via AIM to Kevin Sevcik Send a message via Yahoo to Kevin Sevcik
Re: Shooter Lag

Another more complicated option is to run your shooter at less than the top speed of your motors. The reason it takes longer to spin up is because you're spinning at the top speed of the motor. At that speed, the motor produces zero net torque, and a pretty small amount of torque as it approaches that speed. Less torque means less acceleration, means longer spin up time.

So if you could set things up so that you're only running at, say, 75% of top speed, then your wheel would recover much more quickly. Plus, you'd have a consistent speed for the wheel no matter what your battery level was, since the top speed depends on the voltage you're running at.

The downside is that this is a little complicated to do. You can only do this through closed-loop control of the wheel/motor speed. So you'd need an encoder to measure the wheel or motor speed, and you'd need to set up and tune PID control for the motor speed.
__________________
The difficult we do today; the impossible we do tomorrow. Miracles by appointment only.

Lone Star Regional Troubleshooter