1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
5 Date started: 6/17/2006
7 ------------- Copyright (C) 2006 Jon S. Berndt (jsb@hal-pc.org) -------------
9 This program is free software; you can redistribute it and/or modify it under
10 the terms of the GNU Lesser General Public License as published by the Free Software
11 Foundation; either version 2 of the License, or (at your option) any later
14 This program is distributed in the hope that it will be useful, but WITHOUT
15 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
16 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
19 You should have received a copy of the GNU Lesser General Public License along with
20 this program; if not, write to the Free Software Foundation, Inc., 59 Temple
21 Place - Suite 330, Boston, MA 02111-1307, USA.
23 Further information about the GNU Lesser General Public License can also be found on
24 the world wide web at http://www.gnu.org.
27 --------------------------------------------------------------------------------
28 Initial code 6/17/2006 JSB
30 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
31 COMMENTS, REFERENCES, and NOTES
32 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
42 static const char *IdSrc = "$Id$";
43 static const char *IdHdr = ID_PID;
45 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
47 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
49 FGPID::FGPID(FGFCS* fcs, Element* element) : FGFCSComponent(fcs, element)
51 string kp_string, ki_string, kd_string;
52 dt = fcs->GetState()->Getdt();
62 Input_prev = Input_prev2 = 0.0;
65 if ( element->FindElement("kp") ) {
66 kp_string = element->FindElementValue("kp");
67 if (!is_number(kp_string)) { // property
68 if (kp_string[0] == '-') {
69 KpPropertySign = -1.0;
72 KpPropertyNode = PropertyManager->GetNode(kp_string);
74 Kp = element->FindElementValueAsNumber("kp");
78 if ( element->FindElement("ki") ) {
79 ki_string = element->FindElementValue("ki");
80 if (!is_number(ki_string)) { // property
81 if (ki_string[0] == '-') {
82 KiPropertySign = -1.0;
85 KiPropertyNode = PropertyManager->GetNode(ki_string);
87 Ki = element->FindElementValueAsNumber("ki");
91 if ( element->FindElement("kd") ) {
92 kd_string = element->FindElementValue("kd");
93 if (!is_number(kd_string)) { // property
94 if (kd_string[0] == '-') {
95 KdPropertySign = -1.0;
98 KdPropertyNode = PropertyManager->GetNode(kd_string);
100 Kd = element->FindElementValueAsNumber("kd");
104 if (element->FindElement("trigger")) {
105 Trigger = PropertyManager->GetNode(element->FindElementValue("trigger"));
108 FGFCSComponent::bind();
113 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
120 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
122 bool FGPID::Run(void )
124 double I_out_delta = 0.0;
127 Input = InputNodes[0]->getDoubleValue() * InputSigns[0];
129 if (KpPropertyNode != 0) Kp = KpPropertyNode->getDoubleValue() * KpPropertySign;
130 if (KiPropertyNode != 0) Ki = KiPropertyNode->getDoubleValue() * KiPropertySign;
131 if (KdPropertyNode != 0) Kd = KdPropertyNode->getDoubleValue() * KdPropertySign;
134 D_out = (Kd / dt) * (Input - Input_prev);
136 // Do not continue to integrate the input to the integrator if a wind-up
137 // condition is sensed - that is, if the property pointed to by the trigger
138 // element is non-zero. Reset the integrator to 0.0 if the Trigger value
142 double test = Trigger->getDoubleValue();
143 if (fabs(test) < 0.000001) I_out_delta = Ki * dt * Input; // Normal
144 if (test < 0.0) I_out_total = 0.0; // Reset integrator to 0.0
145 } else { // no anti-wind-up trigger defined
146 I_out_delta = Ki * dt * Input;
149 I_out_total += I_out_delta;
151 Output = P_out + I_out_total + D_out;
154 Input_prev2 = Input_prev;
157 if (IsOutput) SetOutput();
162 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
163 // The bitmasked value choices are as follows:
164 // unset: In this case (the default) JSBSim would only print
165 // out the normally expected messages, essentially echoing
166 // the config files as they are read. If the environment
167 // variable is not set, debug_lvl is set to 1 internally
168 // 0: This requests JSBSim not to output any messages
170 // 1: This value explicity requests the normal JSBSim
172 // 2: This value asks for a message to be printed out when
173 // a class is instantiated
174 // 4: When this value is set, a message is displayed when a
175 // FGModel object executes its Run() method
176 // 8: When this value is set, various runtime state variables
177 // are printed out periodically
178 // 16: When set various parameters are sanity checked and
179 // a message is printed out when they go out of bounds
181 void FGPID::Debug(int from)
183 if (debug_lvl <= 0) return;
185 if (debug_lvl & 1) { // Standard console startup message output
186 if (from == 0) { // Constructor
187 if (InputSigns[0] < 0)
188 cout << " INPUT: -" << InputNodes[0]->getName() << endl;
190 cout << " INPUT: " << InputNodes[0]->getName() << endl;
192 if (IsOutput) cout << " OUTPUT: " << OutputNode->getName() << endl;
195 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
196 if (from == 0) cout << "Instantiated: FGPID" << endl;
197 if (from == 1) cout << "Destroyed: FGPID" << endl;
199 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
201 if (debug_lvl & 8 ) { // Runtime state variables
203 if (debug_lvl & 16) { // Sanity checking
205 if (debug_lvl & 64) {
206 if (from == 0) { // Constructor
207 cout << IdSrc << endl;
208 cout << IdHdr << endl;