1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
5 Date started: 21 February 2006
7 ------------- Copyright (C) 2007 Jon S. Berndt (jon@jsbsim.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 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
40 #include "FGActuator.h"
44 static const char *IdSrc = "$Id$";
45 static const char *IdHdr = ID_ACTUATOR;
47 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
49 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
52 FGActuator::FGActuator(FGFCS* fcs, Element* element) : FGFCSComponent(fcs, element)
56 // inputs are read from the base class constructor
59 PreviousHystOutput = 0.0;
60 PreviousRateLimOutput = 0.0;
61 PreviousLagInput = PreviousLagOutput = 0.0;
62 bias = lag = hysteresis_width = deadband_width = 0.0;
63 rate_limit = 0.0; // no limit
64 fail_zero = fail_hardover = fail_stuck = false;
67 if ( element->FindElement("deadband_width") ) {
68 deadband_width = element->FindElementValueAsNumber("deadband_width");
70 if ( element->FindElement("hysteresis_width") ) {
71 hysteresis_width = element->FindElementValueAsNumber("hysteresis_width");
73 if ( element->FindElement("rate_limit") ) {
74 rate_limit = element->FindElementValueAsNumber("rate_limit");
76 if ( element->FindElement("bias") ) {
77 bias = element->FindElementValueAsNumber("bias");
79 if ( element->FindElement("lag") ) {
80 lag = element->FindElementValueAsNumber("lag");
81 denom = 2.00 + dt*lag;
83 cb = (2.00 - dt*lag) / denom;
86 FGFCSComponent::bind();
92 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
94 FGActuator::~FGActuator()
99 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
101 bool FGActuator::Run(void )
103 Input = InputNodes[0]->getDoubleValue() * InputSigns[0];
105 if (fail_zero) Input = 0;
106 if (fail_hardover) Input = clipmax*sign(Input);
108 Output = Input; // Perfect actuator. At this point, if no failures are present
109 // and no subsequent lag, limiting, etc. is done, the output
110 // is simply the input. If any further processing is done
111 // (below) such as lag, rate limiting, hysteresis, etc., then
112 // the Input will be further processed and the eventual Output
113 // will be overwritten from this perfect value.
115 if (lag != 0.0) Lag(); // models actuator lag
116 if (rate_limit != 0) RateLimit(); // limit the actuator rate
117 if (deadband_width != 0.0) Deadband();
118 if (hysteresis_width != 0.0) Hysteresis();
119 if (bias != 0.0) Bias(); // models a finite bias
121 if (fail_stuck) Output = PreviousOutput;
122 PreviousOutput = Output; // previous value needed for "stuck" malfunction
125 if (IsOutput) SetOutput();
130 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
132 void FGActuator::Bias(void)
137 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
139 void FGActuator::Lag(void)
141 // "Output" on the right side of the "=" is the current frame input
142 // for this Lag filter
143 double input = Output;
144 Output = ca * (input + PreviousLagInput) + PreviousLagOutput * cb;
145 PreviousLagInput = input;
146 PreviousLagOutput = Output;
149 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
151 void FGActuator::Hysteresis(void)
153 // Note: this function acts cumulatively on the "Output" parameter. So, "Output"
154 // is - for the purposes of this Hysteresis method - really the input to the
156 double input = Output;
158 if (input > PreviousHystOutput) {
159 Output = max(PreviousHystOutput, input-0.5*hysteresis_width);
160 } else if (input < PreviousHystOutput) {
161 Output = min(PreviousHystOutput, input+0.5*hysteresis_width);
164 PreviousHystOutput = Output;
167 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
169 void FGActuator::RateLimit(void)
171 // Note: this function acts cumulatively on the "Output" parameter. So, "Output"
172 // is - for the purposes of this RateLimit method - really the input to the
174 double input = Output;
176 double rate = (input - PreviousRateLimOutput)/dt;
177 if (fabs(rate) > rate_limit) {
178 Output = PreviousRateLimOutput + (rate_limit*fabs(rate)/rate)*dt;
181 PreviousRateLimOutput = Output;
184 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
186 void FGActuator::Deadband(void)
190 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
192 void FGActuator::bind(void)
195 if (Name.find("/") == string::npos) {
196 tmp = "fcs/" + PropertyManager->mkPropertyName(Name, true);
198 const string tmp_zero = tmp + "/malfunction/fail_zero";
199 const string tmp_hardover = tmp + "/malfunction/fail_hardover";
200 const string tmp_stuck = tmp + "/malfunction/fail_stuck";
202 PropertyManager->Tie( tmp_zero, this, &FGActuator::GetFailZero, &FGActuator::SetFailZero);
203 PropertyManager->Tie( tmp_hardover, this, &FGActuator::GetFailHardover, &FGActuator::SetFailHardover);
204 PropertyManager->Tie( tmp_stuck, this, &FGActuator::GetFailStuck, &FGActuator::SetFailStuck);
207 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
208 // The bitmasked value choices are as follows:
209 // unset: In this case (the default) JSBSim would only print
210 // out the normally expected messages, essentially echoing
211 // the config files as they are read. If the environment
212 // variable is not set, debug_lvl is set to 1 internally
213 // 0: This requests JSBSim not to output any messages
215 // 1: This value explicity requests the normal JSBSim
217 // 2: This value asks for a message to be printed out when
218 // a class is instantiated
219 // 4: When this value is set, a message is displayed when a
220 // FGModel object executes its Run() method
221 // 8: When this value is set, various runtime state variables
222 // are printed out periodically
223 // 16: When set various parameters are sanity checked and
224 // a message is printed out when they go out of bounds
226 void FGActuator::Debug(int from)
228 if (debug_lvl <= 0) return;
230 if (debug_lvl & 1) { // Standard console startup message output
231 if (from == 0) { // Constructor
232 if (InputSigns[0] < 0)
233 cout << " INPUT: -" << InputNodes[0]->getName() << endl;
235 cout << " INPUT: " << InputNodes[0]->getName() << endl;
238 for (unsigned int i=0; i<OutputNodes.size(); i++)
239 cout << " OUTPUT: " << OutputNodes[i]->getName() << endl;
241 if (bias != 0.0) cout << " Bias: " << bias << endl;
242 if (rate_limit != 0) cout << " Rate limit: " << rate_limit << endl;
243 if (lag != 0) cout << " Actuator lag: " << lag << endl;
244 if (hysteresis_width != 0) cout << " Hysteresis width: " << hysteresis_width << endl;
245 if (deadband_width != 0) cout << " Deadband width: " << deadband_width << endl;
248 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
249 if (from == 0) cout << "Instantiated: FGActuator" << endl;
250 if (from == 1) cout << "Destroyed: FGActuator" << endl;
252 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
254 if (debug_lvl & 8 ) { // Runtime state variables
256 if (debug_lvl & 16) { // Sanity checking
258 if (debug_lvl & 64) {
259 if (from == 0) { // Constructor
260 cout << IdSrc << endl;
261 cout << IdHdr << endl;