diff options
Diffstat (limited to 'src/org/mckenzierobotics/lib/robot/RateLimitedPIDOutput.java')
-rw-r--r-- | src/org/mckenzierobotics/lib/robot/RateLimitedPIDOutput.java | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/src/org/mckenzierobotics/lib/robot/RateLimitedPIDOutput.java b/src/org/mckenzierobotics/lib/robot/RateLimitedPIDOutput.java new file mode 100644 index 0000000..ed36345 --- /dev/null +++ b/src/org/mckenzierobotics/lib/robot/RateLimitedPIDOutput.java @@ -0,0 +1,50 @@ +/** + * Copyright (c) 2012 Precise Path Robotics, Inc + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * @author Luke Shumaker <lukeshu@sbcglobal.net> + */ + +package org.mckenzierobotics.lib.robot; + +import edu.wpi.first.wpilibj.PIDOutput; +import edu.wpi.first.wpilibj.Timer; + +/** + * + * @author Luke Shumaker <lukeshu@sbcglobal.net> + */ +public class RateLimitedPIDOutput implements PIDOutput { + PIDOutput o; + double m; + double prev_rate = 0; + double prev_time = 0; + + public RateLimitedPIDOutput(PIDOutput out, double maxChange) { + o = out; + m = maxChange; + } + + public void pidWrite(double rate) { + double time = Timer.getFPGATimestamp(); + double dTime = time-prev_time; + double dRate = rate-prev_rate; + if (Math.abs(dRate/dTime)>m) { + int sign = (dRate<0?-1:1); + rate = prev_rate+(m*dTime*sign); + } + o.pidWrite(rate); + } +} |