1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
5 Date started: 21 February 2006
7 ------------- Copyright (C) 2007 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.
26 FUNCTIONAL DESCRIPTION
27 --------------------------------------------------------------------------------
30 --------------------------------------------------------------------------------
32 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
33 COMMENTS, REFERENCES, and NOTES
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
38 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
42 #include "FGActuator.h"
46 static const char *IdSrc = "$Id$";
47 static const char *IdHdr = ID_ACTUATOR;
49 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
51 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
54 FGActuator::FGActuator(FGFCS* fcs, Element* element) : FGFCSComponent(fcs, element)
59 // inputs are read from the base class constructor
62 PreviousHystOutput = 0.0;
63 PreviousRateLimOutput = 0.0;
64 PreviousLagInput = PreviousLagOutput = 0.0;
65 bias = lag = hysteresis_width = deadband_width = 0.0;
66 rate_limit = 0.0; // no limit
67 fail_zero = fail_hardover = fail_stuck = false;
70 if ( element->FindElement("deadband_width") ) {
71 deadband_width = element->FindElementValueAsNumber("deadband_width");
73 if ( element->FindElement("hysteresis_width") ) {
74 hysteresis_width = element->FindElementValueAsNumber("hysteresis_width");
76 if ( element->FindElement("rate_limit") ) {
77 rate_limit = element->FindElementValueAsNumber("rate_limit");
79 if ( element->FindElement("bias") ) {
80 bias = element->FindElementValueAsNumber("bias");
82 if ( element->FindElement("lag") ) {
83 lag = element->FindElementValueAsNumber("lag");
84 denom = 2.00 + dt*lag;
86 cb = (2.00 - dt*lag) / denom;
89 FGFCSComponent::bind();
95 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
97 FGActuator::~FGActuator()
102 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
104 bool FGActuator::Run(void )
108 Input = InputNodes[0]->getDoubleValue() * InputSigns[0];
109 Output = Input; // perfect actuator
111 if (fail_zero) Input = 0;
112 if (fail_hardover) Input = clipmax*fabs(Input)/Input;
114 if (lag != 0.0) Lag(); // models actuator lag
115 if (rate_limit != 0) RateLimit(); // limit the actuator rate
116 if (deadband_width != 0.0) Deadband();
117 if (hysteresis_width != 0.0) Hysteresis();
118 if (bias != 0.0) Bias(); // models a finite bias
120 if (fail_stuck) Output = PreviousOutput;
121 PreviousOutput = Output; // previous value needed for "stuck" malfunction
124 if (IsOutput) SetOutput();
129 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
131 void FGActuator::Bias(void)
136 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
138 void FGActuator::Lag(void)
140 // "Output" on the right side of the "=" is the current frame input
141 // for this Lag filter
142 double input = Output;
143 Output = ca * (input + PreviousLagInput) + PreviousLagOutput * cb;
144 PreviousLagInput = input;
145 PreviousLagOutput = Output;
148 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
150 void FGActuator::Hysteresis(void)
152 // Note: this function acts cumulatively on the "Output" parameter. So, "Output"
153 // is - for the purposes of this Hysteresis method - really the input to the
155 double input = Output;
157 if (input > PreviousHystOutput) {
158 Output = std::max(PreviousHystOutput, input-0.5*hysteresis_width);
159 } else if (input < PreviousHystOutput) {
160 Output = std::min(PreviousHystOutput, input+0.5*hysteresis_width);
163 PreviousHystOutput = Output;
166 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
168 void FGActuator::RateLimit(void)
170 // Note: this function acts cumulatively on the "Output" parameter. So, "Output"
171 // is - for the purposes of this RateLimit method - really the input to the
173 double input = Output;
175 double rate = (input - PreviousRateLimOutput)/dt;
176 if (fabs(rate) > rate_limit) {
177 Output = PreviousRateLimOutput + (rate_limit*fabs(rate)/rate)*dt;
180 PreviousRateLimOutput = Output;
183 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
185 void FGActuator::Deadband(void)
189 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
191 void FGActuator::bind(void)
193 string tmp = "fcs/" + PropertyManager->mkPropertyName(Name, true);
194 const string tmp_zero = tmp + "/malfunction/fail_zero";
195 const string tmp_hardover = tmp + "/malfunction/fail_hardover";
196 const string tmp_stuck = tmp + "/malfunction/fail_stuck";
198 PropertyManager->Tie( tmp_zero, this, &FGActuator::GetFailZero, &FGActuator::SetFailZero);
199 PropertyManager->Tie( tmp_hardover, this, &FGActuator::GetFailHardover, &FGActuator::SetFailHardover);
200 PropertyManager->Tie( tmp_stuck, this, &FGActuator::GetFailStuck, &FGActuator::SetFailStuck);
203 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
204 // The bitmasked value choices are as follows:
205 // unset: In this case (the default) JSBSim would only print
206 // out the normally expected messages, essentially echoing
207 // the config files as they are read. If the environment
208 // variable is not set, debug_lvl is set to 1 internally
209 // 0: This requests JSBSim not to output any messages
211 // 1: This value explicity requests the normal JSBSim
213 // 2: This value asks for a message to be printed out when
214 // a class is instantiated
215 // 4: When this value is set, a message is displayed when a
216 // FGModel object executes its Run() method
217 // 8: When this value is set, various runtime state variables
218 // are printed out periodically
219 // 16: When set various parameters are sanity checked and
220 // a message is printed out when they go out of bounds
222 void FGActuator::Debug(int from)
224 if (debug_lvl <= 0) return;
226 if (debug_lvl & 1) { // Standard console startup message output
227 if (from == 0) { // Constructor
228 if (InputSigns[0] < 0)
229 cout << " INPUT: -" << InputNodes[0]->getName() << endl;
231 cout << " INPUT: " << InputNodes[0]->getName() << endl;
233 if (IsOutput) cout << " OUTPUT: " << OutputNode->getName() << endl;
234 if (bias != 0.0) cout << " Bias: " << bias << endl;
235 if (rate_limit != 0) cout << " Rate limit: " << rate_limit << endl;
236 if (lag != 0) cout << " Actuator lag: " << lag << endl;
237 if (hysteresis_width != 0) cout << " Hysteresis width: " << hysteresis_width << endl;
238 if (deadband_width != 0) cout << " Deadband width: " << deadband_width << endl;
241 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
242 if (from == 0) cout << "Instantiated: FGActuator" << endl;
243 if (from == 1) cout << "Destroyed: FGActuator" << endl;
245 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
247 if (debug_lvl & 8 ) { // Runtime state variables
249 if (debug_lvl & 16) { // Sanity checking
251 if (debug_lvl & 64) {
252 if (from == 0) { // Constructor
253 cout << IdSrc << endl;
254 cout << IdHdr << endl;