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/* -------------------------------------------------------------------------- *
* Simbody(tm): Free Water Test *
* -------------------------------------------------------------------------- *
* This is part of the SimTK biosimulation toolkit originating from *
* Simbios, the NIH National Center for Physics-Based Simulation of *
* Biological Structures at Stanford, funded under the NIH Roadmap for *
* Medical Research, grant U54 GM072970. See https://simtk.org/home/simbody. *
* *
* Portions copyright (c) 2009-12 Stanford University and the Authors. *
* Authors: Michael Sherman *
* Contributors: *
* *
* Licensed under the Apache License, Version 2.0 (the "License"); you may *
* not use this file except in compliance with the License. You may obtain a *
* copy of the License at http://www.apache.org/licenses/LICENSE-2.0. *
* *
* Unless required by applicable law or agreed to in writing, software *
* distributed under the License is distributed on an "AS IS" BASIS, *
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
* See the License for the specific language governing permissions and *
* limitations under the License. *
* -------------------------------------------------------------------------- */
/**@file
* This is an outer block for simulating ??? in various ways with Simbody.
* This is about testing Simbody, *not* studying ???!
*/
#include "SimTKsimbody.h"
#include <string>
#include <iostream>
#include <exception>
using std::cout;
using std::cin;
using std::endl;
using namespace SimTK;
static const Real Deg2Rad = (Real)SimTK_DEGREE_TO_RADIAN,
Rad2Deg = (Real)SimTK_RADIAN_TO_DEGREE;
static Real g = 9.8;
static Real m = 1;
int main(int argc, char** argv) {
static const Transform GroundFrame;
static const Rotation ZalongY(UnitVec3(XAxis), XAxis, UnitVec3(YAxis), ZAxis);
static const Rotation ZalongX(UnitVec3(XAxis), ZAxis, UnitVec3(YAxis), YAxis);
static const Rotation YalongZ(UnitVec3(ZAxis), XAxis, UnitVec3(XAxis), YAxis);
static const Vec3 TestLoc(1,0,0);
try { // If anything goes wrong, an exception will be thrown.
// CREATE MULTIBODY SYSTEM AND ITS SUBSYSTEMS
MultibodySystem mbs;
SimbodyMatterSubsystem matter(mbs);
GeneralForceSubsystem forces(mbs);
DecorationSubsystem viz(mbs);
//Force::UniformGravity gravity(forces, matter, Vec3(0, -g, 0));
// ADD BODIES AND THEIR MOBILIZERS
Body::Rigid oxygen = Body::Rigid(MassProperties(m, Vec3(0), Inertia(0)));
oxygen.addDecoration(DecorativeSphere(.1).setColor(Red).setOpacity(.3));
Body::Rigid hydrogen = Body::Rigid(MassProperties(m, Vec3(0), Inertia(0)));
hydrogen.addDecoration(DecorativeSphere(.05).setColor(Green).setOpacity(.3));
MobilizedBody::Cartesian
masslessFrame(matter.Ground(), Transform(ZalongY, Vec3(0)),
MassProperties(0,Vec3(0),Inertia(0)), Transform());
MobilizedBody::Pin
H1(masslessFrame, Transform(), hydrogen, Transform());
MobilizedBody::Pin
O(H1, ZalongY, oxygen, Transform(Vec3(0,1,0)));
MobilizedBody::Universal
H2(O, Transform(YalongZ), hydrogen, Transform(Vec3(0,0,1)));
Force::MobilityLinearSpring(forces, H2, 1, 2, 60*Deg2Rad); // harmonic bend
//MobilizedBody::SphericalCoords
// H2(matter.Ground(), Transform(ZUp, TestLoc),
// particle, Transform(),
// 0*Deg2Rad, false, // azimuth offset, negated
// 0, false, // zenith offset, negated
// ZAxis, true); // translation axis, negated
//anAtom.setDefaultRadius(.1);
//anAtom.setDefaultAngles(Vec2(0, 30*Deg2Rad));
//viz.addRubberBandLine(matter.Ground(), TestLoc,
// anAtom, Vec3(0),
// DecorativeLine().setColor(Orange).setLineThickness(4));
//Force::MobilityLinearSpring(forces, anAtom, 1, 2, 45*Deg2Rad); // harmonic bend
//Force::MobilityLinearSpring(forces, anAtom, 2, 20, .5); // harmonic stretch
//Force::MobilityLinearDamper(forces, anAtom, 0, .1); // harmonic bend
//Force::MobilityLinearDamper(forces, anAtom, 1, .1); // harmonic bend
//Force::MobilityLinearDamper(forces, anAtom, 2, .1); // harmonic stretch
State s = mbs.realizeTopology(); // returns a reference to the the default state
mbs.realizeModel(s); // define appropriate states for this System
mbs.realize(s, Stage::Instance); // instantiate constraints if any
Visualizer display(mbs);
display.setBackgroundColor(White);
display.setBackgroundType(Visualizer::SolidColor);
mbs.realize(s, Stage::Velocity);
display.report(s);
cout << "q=" << s.getQ() << endl;
cout << "u=" << s.getU() << endl;
char c;
//cout << "Default configuration shown. Ready?\n"; cin >> c;
O.setOneQ(s, 0, 30*Deg2Rad);
//H2.setOneQ(s, 0, 30*Deg2Rad);
H2.setOneQ(s, 0, 30*Deg2Rad);
H2.setOneQ(s, 1, 50*Deg2Rad);
s.updU() = Vector(Vec7(0,0,0,1,1,1,0));
//anAtom.setQToFitRotation(s, Rotation(-.9*Pi/2,YAxis));
//while (true) {
// Real x;
// cout << "Torsion (deg)? "; cin >> x; if (x==1234) break;
// Vec2 a = anAtom.getAngles(s); a[0]=x*Deg2Rad; anAtom.setAngles(s, a);
// display.report(s);
// cout << "Bend (deg)? "; cin >> x; if (x==1234) break;
// a = anAtom.getAngles(s); a[1]=x*Deg2Rad; anAtom.setAngles(s, a);
// display.report(s);
// cout << "Radius? "; cin >> x; if (x==1234) break;
// anAtom.setRadius(s, x);
// display.report(s);
//}
//anAtom.setUToFitAngularVelocity(s, Vec3(.1,.2,.3));
//anAtom.setAngle(s, 45*Deg2Rad);
//anAtom.setTranslation(s, Vec2(.4, .1));
mbs.realize(s, Stage::Dynamics);
mbs.realize(s, Stage::Acceleration);
cout << "q=" << s.getQ() << endl;
cout << "u=" << s.getU() << endl;
cout << "qdot=" << s.getQDot() << endl;
cout << "udot=" << s.getUDot() << endl;
cout << "qdotdot=" << s.getQDotDot() << endl;
display.report(s);
cout << "Initialized configuration shown. Ready? ";
cin >> c;
RungeKuttaMersonIntegrator myStudy(mbs);
myStudy.setAccuracy(1e-4);
const Real dt = .02; // output intervals
const Real finalTime = 20;
myStudy.setFinalTime(finalTime);
// Peforms assembly if constraints are violated.
myStudy.initialize(s);
cout << "Using Integrator " << std::string(myStudy.getMethodName()) << ":\n";
cout << "ACCURACY IN USE=" << myStudy.getAccuracyInUse() << endl;
cout << "CTOL IN USE=" << myStudy.getConstraintToleranceInUse() << endl;
cout << "TIMESCALE=" << mbs.getDefaultTimeScale() << endl;
cout << "U WEIGHTS=" << s.getUWeights() << endl;
cout << "Z WEIGHTS=" << s.getZWeights() << endl;
cout << "1/QTOLS=" << s.getQErrWeights() << endl;
cout << "1/UTOLS=" << s.getUErrWeights() << endl;
Integrator::SuccessfulStepStatus status;
int nextReport = 0;
while ((status=myStudy.stepTo(nextReport*dt))
!= Integrator::EndOfSimulation)
{
const State& s = myStudy.getState();
mbs.realize(s);
printf("%5g %10.4g %10.4g %10.4g %10.4g E=%10.8g h%3d=%g %s%s\n", s.getTime(),
H1.getAngle(s), O.getAngle(s), H2.getOneQ(s,0), H2.getOneQ(s,1),
mbs.calcEnergy(s), myStudy.getNumStepsTaken(),
myStudy.getPreviousStepSizeTaken(),
Integrator::getSuccessfulStepStatusString(status).c_str(),
myStudy.isStateInterpolated()?" (INTERP)":"");
display.report(s);
if (status == Integrator::ReachedReportTime)
++nextReport;
}
printf("Using Integrator %s:\n", myStudy.getMethodName());
printf("# STEPS/ATTEMPTS = %d/%d\n", myStudy.getNumStepsTaken(), myStudy.getNumStepsAttempted());
printf("# ERR TEST FAILS = %d\n", myStudy.getNumErrorTestFailures());
printf("# REALIZE/PROJECT = %d/%d\n", myStudy.getNumRealizations(), myStudy.getNumProjections());
}
catch (const std::exception& e) {
printf("EXCEPTION THROWN: %s\n", e.what());
exit(1);
}
catch (...) {
printf("UNKNOWN EXCEPTION THROWN\n");
exit(1);
}
}
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