//========================================================================================================== // Test Cases //========================================================================================================== void testPrescribedForce(OpenSim::Function* forceX, OpenSim::Function* forceY, OpenSim::Function* forceZ, OpenSim::Function* pointX, OpenSim::Function* pointY, OpenSim::Function* pointZ, OpenSim::Function* torqueX, OpenSim::Function* torqueY, OpenSim::Function* torqueZ, vector<SimTK::Real>& times, vector<SimTK::Vec3>& accelerations, vector<SimTK::Vec3>& angularAccelerations) { using namespace SimTK; //========================================================================================================== // Setup OpenSim model Model *osimModel = new Model; //OpenSim bodies OpenSim::Body& ground = osimModel->getGroundBody(); OpenSim::Body ball; ball.setName("ball"); // Add joints FreeJoint free("free", ground, Vec3(0), Vec3(0), ball, Vec3(0), Vec3(0), false); // Rename coordinates for a free joint CoordinateSet free_coords = free.getCoordinateSet(); for(int i=0; i<free_coords.getSize(); i++){ std::stringstream coord_name; coord_name << "free_q" << i; free_coords.get(i).setName(coord_name.str()); free_coords.get(i).setMotionType(i > 2 ? Coordinate::Translational : Coordinate::Rotational); } osimModel->addBody(&ball); osimModel->addJoint(&free); // Add a PrescribedForce. PrescribedForce force(&ball); if (forceX != NULL) force.setForceFunctions(forceX, forceY, forceZ); if (pointX != NULL) force.setPointFunctions(pointX, pointY, pointZ); if (torqueX != NULL) force.setTorqueFunctions(torqueX, torqueY, torqueZ); counter++; osimModel->updForceSet().append(&force); // BAD: have to set memoryOwner to false or program will crash when this test is complete. osimModel->disownAllComponents(); //Set mass ball.setMass(ballMass.getMass()); ball.setMassCenter(ballMass.getMassCenter()); ball.setInertia(ballMass.getInertia()); osimModel->setGravity(gravity_vec); osimModel->print("TestPrescribedForceModel.osim"); delete osimModel; // Check that serialization/deserialization is working correctly as well osimModel = new Model("TestPrescribedForceModel.osim"); SimTK::State& osim_state = osimModel->initSystem(); osimModel->getMultibodySystem().realize(osim_state, Stage::Position ); //========================================================================================================== // Compute the force and torque at the specified times. const OpenSim::Body& body = osimModel->getBodySet().get("ball"); RungeKuttaMersonIntegrator integrator(osimModel->getMultibodySystem() ); Manager manager(*osimModel, integrator); manager.setInitialTime(0.0); for (unsigned int i = 0; i < times.size(); ++i) { manager.setFinalTime(times[i]); manager.integrate(osim_state); osimModel->getMultibodySystem().realize(osim_state, Stage::Acceleration); Vec3 accel, angularAccel; osimModel->updSimbodyEngine().getAcceleration(osim_state, body, Vec3(0), accel); osimModel->updSimbodyEngine().getAngularAcceleration(osim_state, body, angularAccel); ASSERT_EQUAL(accelerations[i][0], accel[0], 1e-10); ASSERT_EQUAL(accelerations[i][1], accel[1], 1e-10); ASSERT_EQUAL(accelerations[i][2], accel[2], 1e-10); ASSERT_EQUAL(angularAccelerations[i][0], angularAccel[0], 1e-10); ASSERT_EQUAL(angularAccelerations[i][1], angularAccel[1], 1e-10); ASSERT_EQUAL(angularAccelerations[i][2], angularAccel[2], 1e-10); } }
// test sphere to sphere contact using elastic foundation with and without // meshes and their combination int testBallToBallContact(bool useElasticFoundation, bool useMesh1, bool useMesh2) { // Setup OpenSim model Model *osimModel = new Model; //OpenSim bodies OpenSim::Body& ground = *new OpenSim::Body("ground", SimTK::Infinity, Vec3(0), Inertia()); osimModel->addBody(&ground); OpenSim::Body ball; ball.setName("ball"); ball.setMass(mass); ball.setMassCenter(Vec3(0)); ball.setInertia(Inertia(1.0)); // Add joints FreeJoint free("free", ground, Vec3(0), Vec3(0), ball, Vec3(0), Vec3(0)); osimModel->addBody(&ball); osimModel->addJoint(&free); // Create ContactGeometry. OpenSim::ContactGeometry *ball1, *ball2; if (useElasticFoundation && useMesh1) ball1 = new ContactMesh(mesh_file, Vec3(0), Vec3(0), ground, "ball1"); else ball1 = new ContactSphere(radius, Vec3(0), ground, "ball1"); if (useElasticFoundation && useMesh2) ball2 = new ContactMesh(mesh_file, Vec3(0), Vec3(0), ball, "ball2"); else ball2 = new ContactSphere(radius, Vec3(0), ball, "ball2"); osimModel->addContactGeometry(ball1); osimModel->addContactGeometry(ball2); OpenSim::Force* force; std::string prefix; if (useElasticFoundation){ } else{ } if (useElasticFoundation) { // Add an ElasticFoundationForce. OpenSim::ElasticFoundationForce::ContactParameters* contactParams = new OpenSim::ElasticFoundationForce::ContactParameters(1.0e6/(2*radius), 0.001, 0.0, 0.0, 0.0); contactParams->addGeometry("ball1"); contactParams->addGeometry("ball2"); force = new OpenSim::ElasticFoundationForce(contactParams); prefix = "EF_"; prefix += useMesh1 ?"Mesh":"noMesh"; prefix += useMesh2 ? "_to_Mesh":"_to_noMesh"; } else { // Add a Hertz HuntCrossleyForce. OpenSim::HuntCrossleyForce::ContactParameters* contactParams = new OpenSim::HuntCrossleyForce::ContactParameters(1.0e6, 0.001, 0.0, 0.0, 0.0); contactParams->addGeometry("ball1"); contactParams->addGeometry("ball2"); force = new OpenSim::HuntCrossleyForce(contactParams); prefix = "Hertz"; } force->setName("contact"); osimModel->addForce(force); osimModel->setGravity(gravity_vec); osimModel->setName(prefix); osimModel->clone()->print(prefix+".osim"); Kinematics* kin = new Kinematics(osimModel); osimModel->addAnalysis(kin); ForceReporter* reporter = new ForceReporter(osimModel); osimModel->addAnalysis(reporter); SimTK::State& osim_state = osimModel->initSystem(); osim_state.updQ()[4] = height; osimModel->getMultibodySystem().realize(osim_state, Stage::Position ); //========================================================================================================== // Simulate it and see if it bounces correctly. cout << "stateY=" << osim_state.getY() << std::endl; RungeKuttaMersonIntegrator integrator(osimModel->getMultibodySystem() ); integrator.setAccuracy(integ_accuracy); integrator.setMaximumStepSize(100*integ_accuracy); Manager manager(*osimModel, integrator); manager.setInitialTime(0.0); manager.setFinalTime(duration); manager.integrate(osim_state); kin->printResults(prefix); reporter->printResults(prefix); osimModel->disownAllComponents(); // model takes ownership of components unless container set is told otherwise delete osimModel; return 0; }