Fabien Lepoutre
/
PID
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PID.cpp@1:272a4f7a8f56, 2012-02-06 (annotated)
- Committer:
- fabienlepoutre
- Date:
- Mon Feb 06 16:07:15 2012 +0000
- Revision:
- 1:272a4f7a8f56
- Parent:
- 0:d5568d657b0c
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| fabienlepoutre | 0:d5568d657b0c | 1 | /** |
| fabienlepoutre | 0:d5568d657b0c | 2 | * @author Aaron Berk |
| fabienlepoutre | 0:d5568d657b0c | 3 | * |
| fabienlepoutre | 0:d5568d657b0c | 4 | * @section LICENSE |
| fabienlepoutre | 0:d5568d657b0c | 5 | * |
| fabienlepoutre | 0:d5568d657b0c | 6 | * Copyright (c) 2010 ARM Limited |
| fabienlepoutre | 0:d5568d657b0c | 7 | * |
| fabienlepoutre | 0:d5568d657b0c | 8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| fabienlepoutre | 0:d5568d657b0c | 9 | * of this software and associated documentation files (the "Software"), to deal |
| fabienlepoutre | 0:d5568d657b0c | 10 | * in the Software without restriction, including without limitation the rights |
| fabienlepoutre | 0:d5568d657b0c | 11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| fabienlepoutre | 0:d5568d657b0c | 12 | * copies of the Software, and to permit persons to whom the Software is |
| fabienlepoutre | 0:d5568d657b0c | 13 | * furnished to do so, subject to the following conditions: |
| fabienlepoutre | 0:d5568d657b0c | 14 | * |
| fabienlepoutre | 0:d5568d657b0c | 15 | * The above copyright notice and this permission notice shall be included in |
| fabienlepoutre | 0:d5568d657b0c | 16 | * all copies or substantial portions of the Software. |
| fabienlepoutre | 0:d5568d657b0c | 17 | * |
| fabienlepoutre | 0:d5568d657b0c | 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| fabienlepoutre | 0:d5568d657b0c | 19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| fabienlepoutre | 0:d5568d657b0c | 20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| fabienlepoutre | 0:d5568d657b0c | 21 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| fabienlepoutre | 0:d5568d657b0c | 22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| fabienlepoutre | 0:d5568d657b0c | 23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| fabienlepoutre | 0:d5568d657b0c | 24 | * THE SOFTWARE. |
| fabienlepoutre | 0:d5568d657b0c | 25 | * |
| fabienlepoutre | 0:d5568d657b0c | 26 | * @section DESCRIPTION |
| fabienlepoutre | 0:d5568d657b0c | 27 | * |
| fabienlepoutre | 0:d5568d657b0c | 28 | * A PID controller is a widely used feedback controller commonly found in |
| fabienlepoutre | 0:d5568d657b0c | 29 | * industry. |
| fabienlepoutre | 0:d5568d657b0c | 30 | * |
| fabienlepoutre | 0:d5568d657b0c | 31 | * This library is a port of Brett Beauregard's Arduino PID library: |
| fabienlepoutre | 0:d5568d657b0c | 32 | * |
| fabienlepoutre | 0:d5568d657b0c | 33 | * http://www.arduino.cc/playground/Code/PIDLibrary |
| fabienlepoutre | 0:d5568d657b0c | 34 | * |
| fabienlepoutre | 0:d5568d657b0c | 35 | * The wikipedia article on PID controllers is a good place to start on |
| fabienlepoutre | 0:d5568d657b0c | 36 | * understanding how they work: |
| fabienlepoutre | 0:d5568d657b0c | 37 | * |
| fabienlepoutre | 0:d5568d657b0c | 38 | * http://en.wikipedia.org/wiki/PID_controller |
| fabienlepoutre | 0:d5568d657b0c | 39 | * |
| fabienlepoutre | 0:d5568d657b0c | 40 | * For a clear and elegant explanation of how to implement and tune a |
| fabienlepoutre | 0:d5568d657b0c | 41 | * controller, the controlguru website by Douglas J. Cooper (who also happened |
| fabienlepoutre | 0:d5568d657b0c | 42 | * to be Brett's controls professor) is an excellent reference: |
| fabienlepoutre | 0:d5568d657b0c | 43 | * |
| fabienlepoutre | 0:d5568d657b0c | 44 | * http://www.controlguru.com/ |
| fabienlepoutre | 0:d5568d657b0c | 45 | */ |
| fabienlepoutre | 0:d5568d657b0c | 46 | |
| fabienlepoutre | 0:d5568d657b0c | 47 | /** |
| fabienlepoutre | 0:d5568d657b0c | 48 | * Includes |
| fabienlepoutre | 0:d5568d657b0c | 49 | */ |
| fabienlepoutre | 0:d5568d657b0c | 50 | #include "PID.h" |
| fabienlepoutre | 0:d5568d657b0c | 51 | |
| fabienlepoutre | 0:d5568d657b0c | 52 | PID::PID(float Kc, float tauI, float tauD, float interval) { |
| fabienlepoutre | 0:d5568d657b0c | 53 | |
| fabienlepoutre | 0:d5568d657b0c | 54 | usingFeedForward = false; |
| fabienlepoutre | 0:d5568d657b0c | 55 | inAuto = false; |
| fabienlepoutre | 0:d5568d657b0c | 56 | |
| fabienlepoutre | 0:d5568d657b0c | 57 | //Default the limits to the full range of I/O: 3.3V |
| fabienlepoutre | 0:d5568d657b0c | 58 | //Make sure to set these to more appropriate limits for |
| fabienlepoutre | 0:d5568d657b0c | 59 | //your application. |
| fabienlepoutre | 0:d5568d657b0c | 60 | setInputLimits(0.0, 3.3); |
| fabienlepoutre | 0:d5568d657b0c | 61 | setOutputLimits(0.0, 3.3); |
| fabienlepoutre | 0:d5568d657b0c | 62 | |
| fabienlepoutre | 0:d5568d657b0c | 63 | tSample_ = interval; |
| fabienlepoutre | 0:d5568d657b0c | 64 | |
| fabienlepoutre | 0:d5568d657b0c | 65 | setTunings(Kc, tauI, tauD); |
| fabienlepoutre | 0:d5568d657b0c | 66 | |
| fabienlepoutre | 0:d5568d657b0c | 67 | setPoint_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 68 | //processVariable_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 69 | // prevProcessVariable_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 70 | prevError_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 71 | Error_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 72 | controllerOutput_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 73 | prevControllerOutput_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 74 | |
| fabienlepoutre | 0:d5568d657b0c | 75 | accError_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 76 | bias_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 77 | |
| fabienlepoutre | 0:d5568d657b0c | 78 | realOutput_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 79 | |
| fabienlepoutre | 0:d5568d657b0c | 80 | } |
| fabienlepoutre | 0:d5568d657b0c | 81 | |
| fabienlepoutre | 0:d5568d657b0c | 82 | void PID::setInputLimits(float inMin, float inMax) { |
| fabienlepoutre | 0:d5568d657b0c | 83 | |
| fabienlepoutre | 0:d5568d657b0c | 84 | //Make sure we haven't been given impossible values. |
| fabienlepoutre | 0:d5568d657b0c | 85 | if (inMin >= inMax) { |
| fabienlepoutre | 0:d5568d657b0c | 86 | return; |
| fabienlepoutre | 0:d5568d657b0c | 87 | } |
| fabienlepoutre | 0:d5568d657b0c | 88 | |
| fabienlepoutre | 0:d5568d657b0c | 89 | //Rescale the working variables to reflect the changes. |
| fabienlepoutre | 0:d5568d657b0c | 90 | prevError_ *= (inMax - inMin) / inSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 91 | accError_ *= (inMax - inMin) / inSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 92 | |
| fabienlepoutre | 0:d5568d657b0c | 93 | //Make sure the working variables are within the new limits. |
| fabienlepoutre | 0:d5568d657b0c | 94 | if (prevError_ > 1) { |
| fabienlepoutre | 0:d5568d657b0c | 95 | prevError_ = 1; |
| fabienlepoutre | 0:d5568d657b0c | 96 | } else if (prevError_ < 0) { |
| fabienlepoutre | 0:d5568d657b0c | 97 | prevError_ = 0; |
| fabienlepoutre | 0:d5568d657b0c | 98 | } |
| fabienlepoutre | 0:d5568d657b0c | 99 | |
| fabienlepoutre | 0:d5568d657b0c | 100 | inMin_ = inMin; |
| fabienlepoutre | 0:d5568d657b0c | 101 | inMax_ = inMax; |
| fabienlepoutre | 0:d5568d657b0c | 102 | inSpan_ = inMax - inMin; |
| fabienlepoutre | 0:d5568d657b0c | 103 | |
| fabienlepoutre | 0:d5568d657b0c | 104 | } |
| fabienlepoutre | 0:d5568d657b0c | 105 | |
| fabienlepoutre | 0:d5568d657b0c | 106 | void PID::setOutputLimits(float outMin, float outMax) { |
| fabienlepoutre | 0:d5568d657b0c | 107 | |
| fabienlepoutre | 0:d5568d657b0c | 108 | //Make sure we haven't been given impossible values. |
| fabienlepoutre | 0:d5568d657b0c | 109 | if (outMin >= outMax) { |
| fabienlepoutre | 0:d5568d657b0c | 110 | return; |
| fabienlepoutre | 0:d5568d657b0c | 111 | } |
| fabienlepoutre | 0:d5568d657b0c | 112 | |
| fabienlepoutre | 0:d5568d657b0c | 113 | //Rescale the working variables to reflect the changes. |
| fabienlepoutre | 0:d5568d657b0c | 114 | prevControllerOutput_ *= (outMax - outMin) / outSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 115 | |
| fabienlepoutre | 0:d5568d657b0c | 116 | //Make sure the working variables are within the new limits. |
| fabienlepoutre | 0:d5568d657b0c | 117 | if (prevControllerOutput_ > 1) { |
| fabienlepoutre | 0:d5568d657b0c | 118 | prevControllerOutput_ = 1; |
| fabienlepoutre | 0:d5568d657b0c | 119 | } else if (prevControllerOutput_ < 0) { |
| fabienlepoutre | 0:d5568d657b0c | 120 | prevControllerOutput_ = 0; |
| fabienlepoutre | 0:d5568d657b0c | 121 | } |
| fabienlepoutre | 0:d5568d657b0c | 122 | |
| fabienlepoutre | 0:d5568d657b0c | 123 | outMin_ = outMin; |
| fabienlepoutre | 0:d5568d657b0c | 124 | outMax_ = outMax; |
| fabienlepoutre | 0:d5568d657b0c | 125 | outSpan_ = outMax - outMin; |
| fabienlepoutre | 0:d5568d657b0c | 126 | |
| fabienlepoutre | 0:d5568d657b0c | 127 | } |
| fabienlepoutre | 0:d5568d657b0c | 128 | |
| fabienlepoutre | 0:d5568d657b0c | 129 | void PID::setTunings(float Kc, float tauI, float tauD) { |
| fabienlepoutre | 0:d5568d657b0c | 130 | |
| fabienlepoutre | 0:d5568d657b0c | 131 | //Verify that the tunings make sense. |
| fabienlepoutre | 0:d5568d657b0c | 132 | if (Kc == 0.0 || tauI < 0.0 || tauD < 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 133 | return; |
| fabienlepoutre | 0:d5568d657b0c | 134 | } |
| fabienlepoutre | 0:d5568d657b0c | 135 | |
| fabienlepoutre | 0:d5568d657b0c | 136 | //Store raw values to hand back to user on request. |
| fabienlepoutre | 0:d5568d657b0c | 137 | pParam_ = Kc; |
| fabienlepoutre | 0:d5568d657b0c | 138 | iParam_ = tauI; |
| fabienlepoutre | 0:d5568d657b0c | 139 | dParam_ = tauD; |
| fabienlepoutre | 0:d5568d657b0c | 140 | |
| fabienlepoutre | 0:d5568d657b0c | 141 | float tempTauR; |
| fabienlepoutre | 0:d5568d657b0c | 142 | |
| fabienlepoutre | 0:d5568d657b0c | 143 | if (tauI == 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 144 | tempTauR = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 145 | } else { |
| fabienlepoutre | 0:d5568d657b0c | 146 | tempTauR = (1.0 / tauI) * tSample_; |
| fabienlepoutre | 0:d5568d657b0c | 147 | } |
| fabienlepoutre | 0:d5568d657b0c | 148 | |
| fabienlepoutre | 0:d5568d657b0c | 149 | //For "bumpless transfer" we need to rescale the accumulated error. |
| fabienlepoutre | 0:d5568d657b0c | 150 | if (inAuto) { |
| fabienlepoutre | 0:d5568d657b0c | 151 | if (tempTauR == 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 152 | accError_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 153 | } else { |
| fabienlepoutre | 0:d5568d657b0c | 154 | accError_ *= (Kc_ * tauR_) / (Kc * tempTauR); |
| fabienlepoutre | 0:d5568d657b0c | 155 | } |
| fabienlepoutre | 0:d5568d657b0c | 156 | } |
| fabienlepoutre | 0:d5568d657b0c | 157 | |
| fabienlepoutre | 0:d5568d657b0c | 158 | Kc_ = Kc; |
| fabienlepoutre | 0:d5568d657b0c | 159 | tauR_ = tempTauR; |
| fabienlepoutre | 0:d5568d657b0c | 160 | tauD_ = tauD / tSample_; |
| fabienlepoutre | 0:d5568d657b0c | 161 | |
| fabienlepoutre | 0:d5568d657b0c | 162 | } |
| fabienlepoutre | 0:d5568d657b0c | 163 | |
| fabienlepoutre | 0:d5568d657b0c | 164 | void PID::reset(void) { |
| fabienlepoutre | 0:d5568d657b0c | 165 | |
| fabienlepoutre | 0:d5568d657b0c | 166 | float scaledBias = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 167 | |
| fabienlepoutre | 0:d5568d657b0c | 168 | if (usingFeedForward) { |
| fabienlepoutre | 0:d5568d657b0c | 169 | scaledBias = (bias_ - outMin_) / outSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 170 | } else { |
| fabienlepoutre | 0:d5568d657b0c | 171 | scaledBias = (realOutput_ - outMin_) / outSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 172 | } |
| fabienlepoutre | 0:d5568d657b0c | 173 | |
| fabienlepoutre | 0:d5568d657b0c | 174 | prevControllerOutput_ = scaledBias; |
| fabienlepoutre | 0:d5568d657b0c | 175 | prevError_ = (Error_ - inMin_) / inSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 176 | |
| fabienlepoutre | 0:d5568d657b0c | 177 | //Clear any error in the integral. |
| fabienlepoutre | 0:d5568d657b0c | 178 | accError_ = 0; |
| fabienlepoutre | 0:d5568d657b0c | 179 | |
| fabienlepoutre | 0:d5568d657b0c | 180 | } |
| fabienlepoutre | 0:d5568d657b0c | 181 | |
| fabienlepoutre | 0:d5568d657b0c | 182 | void PID::setMode(int mode) { |
| fabienlepoutre | 0:d5568d657b0c | 183 | |
| fabienlepoutre | 0:d5568d657b0c | 184 | //We were in manual, and we just got set to auto. |
| fabienlepoutre | 0:d5568d657b0c | 185 | //Reset the controller internals. |
| fabienlepoutre | 0:d5568d657b0c | 186 | if (mode != 0 && !inAuto) { |
| fabienlepoutre | 0:d5568d657b0c | 187 | reset(); |
| fabienlepoutre | 0:d5568d657b0c | 188 | } |
| fabienlepoutre | 0:d5568d657b0c | 189 | |
| fabienlepoutre | 0:d5568d657b0c | 190 | inAuto = (mode != 0); |
| fabienlepoutre | 0:d5568d657b0c | 191 | |
| fabienlepoutre | 0:d5568d657b0c | 192 | } |
| fabienlepoutre | 0:d5568d657b0c | 193 | |
| fabienlepoutre | 0:d5568d657b0c | 194 | void PID::setInterval(float interval) { |
| fabienlepoutre | 0:d5568d657b0c | 195 | |
| fabienlepoutre | 0:d5568d657b0c | 196 | if (interval > 0) { |
| fabienlepoutre | 0:d5568d657b0c | 197 | //Convert the time-based tunings to reflect this change. |
| fabienlepoutre | 0:d5568d657b0c | 198 | tauR_ *= (interval / tSample_); |
| fabienlepoutre | 0:d5568d657b0c | 199 | accError_ *= (tSample_ / interval); |
| fabienlepoutre | 0:d5568d657b0c | 200 | tauD_ *= (interval / tSample_); |
| fabienlepoutre | 0:d5568d657b0c | 201 | tSample_ = interval; |
| fabienlepoutre | 0:d5568d657b0c | 202 | } |
| fabienlepoutre | 0:d5568d657b0c | 203 | |
| fabienlepoutre | 0:d5568d657b0c | 204 | } |
| fabienlepoutre | 0:d5568d657b0c | 205 | |
| fabienlepoutre | 0:d5568d657b0c | 206 | void PID::setSetPoint(float sp) { |
| fabienlepoutre | 0:d5568d657b0c | 207 | |
| fabienlepoutre | 0:d5568d657b0c | 208 | setPoint_ = sp; |
| fabienlepoutre | 0:d5568d657b0c | 209 | |
| fabienlepoutre | 0:d5568d657b0c | 210 | } |
| fabienlepoutre | 0:d5568d657b0c | 211 | |
| fabienlepoutre | 0:d5568d657b0c | 212 | void PID::setError(float error){ |
| fabienlepoutre | 0:d5568d657b0c | 213 | Error_ = error; |
| fabienlepoutre | 0:d5568d657b0c | 214 | } |
| fabienlepoutre | 0:d5568d657b0c | 215 | |
| fabienlepoutre | 0:d5568d657b0c | 216 | void PID::setProcessValue(float pv) { |
| fabienlepoutre | 0:d5568d657b0c | 217 | |
| fabienlepoutre | 0:d5568d657b0c | 218 | // processVariable_ = pv; |
| fabienlepoutre | 0:d5568d657b0c | 219 | |
| fabienlepoutre | 0:d5568d657b0c | 220 | } |
| fabienlepoutre | 0:d5568d657b0c | 221 | |
| fabienlepoutre | 0:d5568d657b0c | 222 | void PID::setBias(float bias){ |
| fabienlepoutre | 0:d5568d657b0c | 223 | |
| fabienlepoutre | 0:d5568d657b0c | 224 | bias_ = bias; |
| fabienlepoutre | 0:d5568d657b0c | 225 | usingFeedForward = 1; |
| fabienlepoutre | 0:d5568d657b0c | 226 | |
| fabienlepoutre | 0:d5568d657b0c | 227 | } |
| fabienlepoutre | 0:d5568d657b0c | 228 | |
| fabienlepoutre | 0:d5568d657b0c | 229 | float PID::compute() { |
| fabienlepoutre | 0:d5568d657b0c | 230 | |
| fabienlepoutre | 0:d5568d657b0c | 231 | //Pull in the input and setpoint, and scale them into percent span. |
| fabienlepoutre | 0:d5568d657b0c | 232 | /* float scaledPV = (processVariable_ - inMin_) / inSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 233 | |
| fabienlepoutre | 0:d5568d657b0c | 234 | if (scaledPV > 1.0) { |
| fabienlepoutre | 0:d5568d657b0c | 235 | scaledPV = 1.0; |
| fabienlepoutre | 0:d5568d657b0c | 236 | } else if (scaledPV < 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 237 | scaledPV = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 238 | } |
| fabienlepoutre | 0:d5568d657b0c | 239 | |
| fabienlepoutre | 0:d5568d657b0c | 240 | float scaledSP = (setPoint_ - inMin_) / inSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 241 | if (scaledSP > 1.0) { |
| fabienlepoutre | 0:d5568d657b0c | 242 | scaledSP = 1; |
| fabienlepoutre | 0:d5568d657b0c | 243 | } else if (scaledSP < 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 244 | scaledSP = 0; |
| fabienlepoutre | 0:d5568d657b0c | 245 | }*/ |
| fabienlepoutre | 0:d5568d657b0c | 246 | |
| fabienlepoutre | 0:d5568d657b0c | 247 | |
| fabienlepoutre | 0:d5568d657b0c | 248 | float ScaledError = (Error_ -inMin_)/inSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 249 | if (ScaledError > 1.0) { |
| fabienlepoutre | 0:d5568d657b0c | 250 | ScaledError = 1; |
| fabienlepoutre | 0:d5568d657b0c | 251 | } else if (ScaledError < 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 252 | ScaledError = 0; |
| fabienlepoutre | 0:d5568d657b0c | 253 | } |
| fabienlepoutre | 0:d5568d657b0c | 254 | |
| fabienlepoutre | 0:d5568d657b0c | 255 | //Check and see if the output is pegged at a limit and only |
| fabienlepoutre | 0:d5568d657b0c | 256 | //integrate if it is not. This is to prevent reset-windup. |
| fabienlepoutre | 0:d5568d657b0c | 257 | if (!(prevControllerOutput_ >= 1 && ScaledError > 0) && !(prevControllerOutput_ <= 0 && ScaledError < 0)) { |
| fabienlepoutre | 0:d5568d657b0c | 258 | accError_ += ScaledError; |
| fabienlepoutre | 0:d5568d657b0c | 259 | } |
| fabienlepoutre | 0:d5568d657b0c | 260 | |
| fabienlepoutre | 0:d5568d657b0c | 261 | //Compute the current slope of the input signal. |
| fabienlepoutre | 0:d5568d657b0c | 262 | float dMeas = (ScaledError - prevError_) / tSample_; |
| fabienlepoutre | 0:d5568d657b0c | 263 | |
| fabienlepoutre | 0:d5568d657b0c | 264 | float scaledBias = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 265 | |
| fabienlepoutre | 0:d5568d657b0c | 266 | if (usingFeedForward) { |
| fabienlepoutre | 0:d5568d657b0c | 267 | scaledBias = (bias_ - outMin_) / outSpan_; |
| fabienlepoutre | 0:d5568d657b0c | 268 | } |
| fabienlepoutre | 0:d5568d657b0c | 269 | |
| fabienlepoutre | 0:d5568d657b0c | 270 | //Perform the PID calculation. |
| fabienlepoutre | 0:d5568d657b0c | 271 | controllerOutput_ = scaledBias + Kc_ * (ScaledError + (tauR_ * accError_) - (tauD_ * dMeas)); |
| fabienlepoutre | 0:d5568d657b0c | 272 | |
| fabienlepoutre | 0:d5568d657b0c | 273 | //Make sure the computed output is within output constraints. |
| fabienlepoutre | 0:d5568d657b0c | 274 | if (controllerOutput_ < 0.0) { |
| fabienlepoutre | 0:d5568d657b0c | 275 | controllerOutput_ = 0.0; |
| fabienlepoutre | 0:d5568d657b0c | 276 | } else if (controllerOutput_ > 1.0) { |
| fabienlepoutre | 0:d5568d657b0c | 277 | controllerOutput_ = 1.0; |
| fabienlepoutre | 0:d5568d657b0c | 278 | } |
| fabienlepoutre | 0:d5568d657b0c | 279 | |
| fabienlepoutre | 0:d5568d657b0c | 280 | //Remember this output for the windup check next time. |
| fabienlepoutre | 0:d5568d657b0c | 281 | prevControllerOutput_ = controllerOutput_; |
| fabienlepoutre | 0:d5568d657b0c | 282 | //Remember the input for the derivative calculation next time. |
| fabienlepoutre | 0:d5568d657b0c | 283 | prevError_ = ScaledError; |
| fabienlepoutre | 0:d5568d657b0c | 284 | |
| fabienlepoutre | 0:d5568d657b0c | 285 | //Scale the output from percent span back out to a real world number. |
| fabienlepoutre | 0:d5568d657b0c | 286 | return ((controllerOutput_ * outSpan_) + outMin_); |
| fabienlepoutre | 0:d5568d657b0c | 287 | |
| fabienlepoutre | 0:d5568d657b0c | 288 | } |
| fabienlepoutre | 0:d5568d657b0c | 289 | |
| fabienlepoutre | 0:d5568d657b0c | 290 | float PID::getInMin() { |
| fabienlepoutre | 0:d5568d657b0c | 291 | |
| fabienlepoutre | 0:d5568d657b0c | 292 | return inMin_; |
| fabienlepoutre | 0:d5568d657b0c | 293 | |
| fabienlepoutre | 0:d5568d657b0c | 294 | } |
| fabienlepoutre | 0:d5568d657b0c | 295 | |
| fabienlepoutre | 0:d5568d657b0c | 296 | float PID::getInMax() { |
| fabienlepoutre | 0:d5568d657b0c | 297 | |
| fabienlepoutre | 0:d5568d657b0c | 298 | return inMax_; |
| fabienlepoutre | 0:d5568d657b0c | 299 | |
| fabienlepoutre | 0:d5568d657b0c | 300 | } |
| fabienlepoutre | 0:d5568d657b0c | 301 | |
| fabienlepoutre | 0:d5568d657b0c | 302 | float PID::getOutMin() { |
| fabienlepoutre | 0:d5568d657b0c | 303 | |
| fabienlepoutre | 0:d5568d657b0c | 304 | return outMin_; |
| fabienlepoutre | 0:d5568d657b0c | 305 | |
| fabienlepoutre | 0:d5568d657b0c | 306 | } |
| fabienlepoutre | 0:d5568d657b0c | 307 | |
| fabienlepoutre | 0:d5568d657b0c | 308 | float PID::getOutMax() { |
| fabienlepoutre | 0:d5568d657b0c | 309 | |
| fabienlepoutre | 0:d5568d657b0c | 310 | return outMax_; |
| fabienlepoutre | 0:d5568d657b0c | 311 | |
| fabienlepoutre | 0:d5568d657b0c | 312 | } |
| fabienlepoutre | 0:d5568d657b0c | 313 | |
| fabienlepoutre | 0:d5568d657b0c | 314 | float PID::getInterval() { |
| fabienlepoutre | 0:d5568d657b0c | 315 | |
| fabienlepoutre | 0:d5568d657b0c | 316 | return tSample_; |
| fabienlepoutre | 0:d5568d657b0c | 317 | |
| fabienlepoutre | 0:d5568d657b0c | 318 | } |
| fabienlepoutre | 0:d5568d657b0c | 319 | |
| fabienlepoutre | 0:d5568d657b0c | 320 | float PID::getPParam() { |
| fabienlepoutre | 0:d5568d657b0c | 321 | |
| fabienlepoutre | 0:d5568d657b0c | 322 | return pParam_; |
| fabienlepoutre | 0:d5568d657b0c | 323 | |
| fabienlepoutre | 0:d5568d657b0c | 324 | } |
| fabienlepoutre | 0:d5568d657b0c | 325 | |
| fabienlepoutre | 0:d5568d657b0c | 326 | float PID::getIParam() { |
| fabienlepoutre | 0:d5568d657b0c | 327 | |
| fabienlepoutre | 0:d5568d657b0c | 328 | return iParam_; |
| fabienlepoutre | 0:d5568d657b0c | 329 | |
| fabienlepoutre | 0:d5568d657b0c | 330 | } |
| fabienlepoutre | 0:d5568d657b0c | 331 | |
| fabienlepoutre | 0:d5568d657b0c | 332 | float PID::getDParam() { |
| fabienlepoutre | 0:d5568d657b0c | 333 | |
| fabienlepoutre | 0:d5568d657b0c | 334 | return dParam_; |
| fabienlepoutre | 0:d5568d657b0c | 335 | |
| fabienlepoutre | 0:d5568d657b0c | 336 | } |