// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
void ChTrackTestRig::AddVisualize_post(std::shared_ptr<ChBody> post_body,
std::shared_ptr<ChBody> chassis_body,
double length,
double width,
double height,
const ChColor& color) {
// Platform (on post body)
auto base_box = std::make_shared<ChBoxShape>();
base_box->GetBoxGeometry().SetLengths(ChVector<>(length, width, height));
post_body->AddAsset(base_box);
auto col = std::make_shared<ChColorAsset>();
col->SetColor(color);
post_body->AddAsset(col);
// Piston (on post body)
auto piston = std::make_shared<ChCylinderShape>();
piston->GetCylinderGeometry().rad = width / 6.0;
piston->GetCylinderGeometry().p1 = ChVector<>(0, 0, -height / 2.0);
piston->GetCylinderGeometry().p2 = ChVector<>(0, 0, -height * 12.0);
post_body->AddAsset(piston); // add asset to post body
// Post sleeve (on chassis/ground body)
auto cyl = std::make_shared<ChCylinderShape>();
cyl->GetCylinderGeometry().rad = width / 4.0;
cyl->GetCylinderGeometry().p1 = post_body->GetPos() - ChVector<>(0, 0, 8 * height);
cyl->GetCylinderGeometry().p2 = post_body->GetPos() - ChVector<>(0, 0, 16 * height);
chassis_body->AddAsset(cyl);
}
void ChTrackShoeBandBushing::AddWebVisualization(std::shared_ptr<ChBody> segment) {
segment->AddAsset(std::make_shared<ChColorAsset>(GetColor(m_index)));
auto box = std::make_shared<ChBoxShape>();
box->GetBoxGeometry().SetLengths(ChVector<>(m_seg_length, GetBeltWidth(), GetWebThickness()));
segment->AddAsset(box);
auto cyl = std::make_shared<ChCylinderShape>();
double radius = GetWebThickness() / 4;
cyl->GetCylinderGeometry().rad = radius;
cyl->GetCylinderGeometry().p1 = ChVector<>(m_seg_length / 2, -GetBeltWidth() / 2 - 2 * radius, 0);
cyl->GetCylinderGeometry().p2 = ChVector<>(m_seg_length / 2, +GetBeltWidth() / 2 + 2 * radius, 0);
segment->AddAsset(cyl);
}
void AddWall(std::shared_ptr<ChBody> body, const ChVector<>& dim, const ChVector<>& loc) {
body->GetCollisionModel()->AddBox(dim.x(), dim.y(), dim.z(), loc);
auto box = std::make_shared<ChBoxShape>();
box->GetBoxGeometry().Size = dim;
box->GetBoxGeometry().Pos = loc;
box->SetColor(ChColor(1, 0, 0));
box->SetFading(0.6f);
body->AddAsset(box);
}
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
void ChDoubleWishboneReduced::AddVisualizationUpright(std::shared_ptr<ChBody> upright,
const ChVector<> pt_C,
const ChVector<> pt_U,
const ChVector<> pt_L,
const ChVector<> pt_T,
double radius) {
static const double threshold2 = 1e-6;
// Express hardpoint locations in body frame.
ChVector<> p_C = upright->TransformPointParentToLocal(pt_C);
ChVector<> p_U = upright->TransformPointParentToLocal(pt_U);
ChVector<> p_L = upright->TransformPointParentToLocal(pt_L);
ChVector<> p_T = upright->TransformPointParentToLocal(pt_T);
if ((p_L - p_C).Length2() > threshold2) {
auto cyl_L = std::make_shared<ChCylinderShape>();
cyl_L->GetCylinderGeometry().p1 = p_L;
cyl_L->GetCylinderGeometry().p2 = p_C;
cyl_L->GetCylinderGeometry().rad = radius;
upright->AddAsset(cyl_L);
}
if ((p_U - p_C).Length2() > threshold2) {
auto cyl_U = std::make_shared<ChCylinderShape>();
cyl_U->GetCylinderGeometry().p1 = p_U;
cyl_U->GetCylinderGeometry().p2 = p_C;
cyl_U->GetCylinderGeometry().rad = radius;
upright->AddAsset(cyl_U);
}
if ((p_T - p_C).Length2() > threshold2) {
auto cyl_T = std::make_shared<ChCylinderShape>();
cyl_T->GetCylinderGeometry().p1 = p_T;
cyl_T->GetCylinderGeometry().p2 = p_C;
cyl_T->GetCylinderGeometry().rad = radius;
upright->AddAsset(cyl_T);
}
auto col = std::make_shared<ChColorAsset>();
col->SetColor(ChColor(0.2f, 0.2f, 0.6f));
upright->AddAsset(col);
}
void AddContainerWall(std::shared_ptr<ChBody> body,
const ChVector<>& pos,
const ChVector<>& size,
bool visible = true) {
ChVector<> hsize = 0.5 * size;
body->GetCollisionModel()->AddBox(hsize.x(), hsize.y(), hsize.z(), pos);
if (visible) {
auto box = std::make_shared<ChBoxShape>();
box->GetBoxGeometry().Pos = pos;
box->GetBoxGeometry().Size = hsize;
box->SetColor(ChColor(1, 0, 0));
box->SetFading(0.6f);
body->AddAsset(box);
}
}
// Use convex decomposition for collision detection with the Trelleborg tire
SoilbinWheel(ChSystemNSC* system, ChVector<> mposition, double mass, ChVector<>& inertia) {
ChCollisionModel::SetDefaultSuggestedEnvelope(0.005);
ChCollisionModel::SetDefaultSuggestedMargin(0.004);
// Create the wheel body
wheel = std::make_shared<ChBody>();
wheel->SetPos(mposition);
wheel->SetMass(mass);
wheel->SetInertiaXX(inertia);
wheel->GetMaterialSurfaceNSC()->SetFriction(0.4f);
wheel->SetCollide(true);
// Visualization mesh
auto tireMesh = std::make_shared<ChTriangleMeshConnected>();
tireMesh->LoadWavefrontMesh(GetChronoDataFile("tractor_wheel.obj"), true, true);
auto tireMesh_asset = std::make_shared<ChTriangleMeshShape>();
tireMesh_asset->SetMesh(tireMesh);
wheel->AddAsset(tireMesh_asset);
// Contact mesh
wheel->GetCollisionModel()->ClearModel();
// Describe the (invisible) colliding shape by adding the 'carcass' decomposed shape and the
// 'knobs'. Since these decompositions are only for 1/15th of the wheel, use for() to pattern them.
for (double mangle = 0; mangle < 360.; mangle += (360. / 15.)) {
ChQuaternion<> myrot;
ChStreamInAsciiFile myknobs(GetChronoDataFile("tractor_wheel_knobs.chulls").c_str());
ChStreamInAsciiFile myslice(GetChronoDataFile("tractor_wheel_slice.chulls").c_str());
myrot.Q_from_AngAxis(mangle * (CH_C_PI / 180.), VECT_X);
ChMatrix33<> mm(myrot);
wheel->GetCollisionModel()->AddConvexHullsFromFile(myknobs, ChVector<>(0, 0, 0), mm);
wheel->GetCollisionModel()->AddConvexHullsFromFile(myslice, ChVector<>(0, 0, 0), mm);
}
wheel->GetCollisionModel()->BuildModel();
// Add wheel body to system
system->AddBody(wheel);
}
// Build and initialize the forklift, creating all bodies corresponding to
// the various parts and adding them to the physical system - also creating
// and adding constraints to the system.
MySimpleForklift(ChIrrAppInterface* app, ChVector<> offset = ChVector<>(0, 0, 0)) {
throttle = 0; // initially, gas throttle is 0.
steer = 0;
lift = 0;
ChVector<> COG_truss(0, 0.4, 0.5);
ChVector<> COG_wheelRF(-0.566, 0.282, 1.608);
ChVector<> COG_wheelLF(0.566, 0.282, 1.608);
ChVector<> COG_arm(0, 1.300, 1.855);
ChVector<> COG_fork(0, 0.362, 2.100);
ChVector<> COG_wheelB(0, 0.282, 0.003);
ChVector<> POS_pivotarm(0, 0.150, 1.855);
ChVector<> POS_prismatic(0, 0.150, 1.855);
double RAD_back_wheel = 0.28;
double RAD_front_wheel = 0.28;
forkliftTiremap = app->GetVideoDriver()->getTexture(GetChronoDataFile("tire_truck.png").c_str());
// --- The car body ---
truss = std::make_shared<ChBody>();
app->GetSystem()->Add(truss);
truss->SetPos(COG_truss);
truss->SetMass(200);
truss->SetInertiaXX(ChVector<>(100, 100, 100));
// collision properties:
truss->GetCollisionModel()->ClearModel();
truss->GetCollisionModel()->AddBox(1.227 / 2., 1.621 / 2., 1.864 / 2., ChVector<>(-0.003, 1.019, 0.192));
truss->GetCollisionModel()->AddBox(0.187 / 2., 0.773 / 2., 1.201 / 2., ChVector<>(0.486, 0.153, -0.047));
truss->GetCollisionModel()->AddBox(0.187 / 2., 0.773 / 2., 1.201 / 2., ChVector<>(-0.486, 0.153, -0.047));
truss->GetCollisionModel()->BuildModel();
truss->SetCollide(true);
// visualization properties:
auto truss_asset_assembly = std::make_shared<ChAssetLevel>();
truss_asset_assembly->GetFrame().SetPos(-COG_truss);
truss->AddAsset(truss_asset_assembly);
auto truss_mesh = std::make_shared<ChObjShapeFile>();
truss_mesh->SetFilename(GetChronoDataFile("forklift_body.obj"));
truss_asset_assembly->AddAsset(truss_mesh);
auto truss_texture = std::make_shared<ChTexture>(GetChronoDataFile("tire_truck.png"));
truss_asset_assembly->AddAsset(truss_texture);
// ..the right-front wheel
wheelRF = std::make_shared<ChBody>();
app->GetSystem()->Add(wheelRF);
wheelRF->SetPos(COG_wheelRF);
wheelRF->SetMass(20);
wheelRF->SetInertiaXX(ChVector<>(2, 2, 2));
// collision properties:
ChMatrix33<> Arot(chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Z));
wheelRF->GetCollisionModel()->ClearModel();
wheelRF->GetCollisionModel()->AddCylinder(RAD_front_wheel, RAD_front_wheel, 0.1, ChVector<>(0, 0, 0), Arot);
wheelRF->GetCollisionModel()->BuildModel();
wheelRF->SetCollide(true);
// visualization properties:
auto wheelRF_asset_assembly = std::make_shared<ChAssetLevel>();
wheelRF_asset_assembly->GetFrame().SetPos(-COG_wheelRF);
wheelRF->AddAsset(wheelRF_asset_assembly);
auto wheelRF_mesh = std::make_shared<ChObjShapeFile>();
wheelRF_mesh->SetFilename(GetChronoDataFile("wheel.obj"));
wheelRF_asset_assembly->AddAsset(wheelRF_mesh);
auto wheelRF_texture = std::make_shared<ChTexture>(GetChronoDataFile("tire_truck.png"));
wheelRF_asset_assembly->AddAsset(wheelRF_texture);
// .. create the revolute joint between the wheel and the truss
link_revoluteRF = std::make_shared<ChLinkLockRevolute>(); // right, front, upper, 1
link_revoluteRF->Initialize(wheelRF, truss,
ChCoordsys<>(COG_wheelRF, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Y)));
app->GetSystem()->AddLink(link_revoluteRF);
// ..the left-front wheel
wheelLF = std::make_shared<ChBody>();
app->GetSystem()->Add(wheelLF);
wheelLF->SetPos(COG_wheelLF);
wheelLF->SetRot(chrono::Q_from_AngAxis(CH_C_PI, VECT_Y)); // reuse RF wheel shape, flipped
wheelLF->SetMass(20);
wheelLF->SetInertiaXX(ChVector<>(2, 2, 2));
// collision properties:
wheelLF->GetCollisionModel()->ClearModel();
wheelLF->GetCollisionModel()->AddCylinder(RAD_front_wheel, RAD_front_wheel, 0.1, ChVector<>(0, 0, 0), Arot);
wheelLF->GetCollisionModel()->BuildModel();
wheelLF->SetCollide(true);
// visualization properties:
auto wheelLF_asset_assembly = std::make_shared<ChAssetLevel>();
wheelLF_asset_assembly->GetFrame().SetPos(-COG_wheelRF);
wheelLF->AddAsset(wheelLF_asset_assembly);
auto wheelLF_mesh = std::make_shared<ChObjShapeFile>();
wheelLF_mesh->SetFilename(GetChronoDataFile("wheel.obj"));
wheelLF_asset_assembly->AddAsset(wheelLF_mesh);
auto wheelLF_texture = std::make_shared<ChTexture>(GetChronoDataFile("tire_truck.png"));
wheelLF_asset_assembly->AddAsset(wheelLF_texture);
// .. create the revolute joint between the wheel and the truss
link_revoluteLF = std::make_shared<ChLinkLockRevolute>(); // right, front, upper, 1
link_revoluteLF->Initialize(wheelLF, truss,
ChCoordsys<>(COG_wheelLF, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Y)));
app->GetSystem()->AddLink(link_revoluteLF);
// ..the back steering spindle (invisible, no mesh)
spindleB = std::make_shared<ChBody>();
app->GetSystem()->Add(spindleB);
spindleB->SetPos(COG_wheelB);
spindleB->SetMass(10);
spindleB->SetInertiaXX(ChVector<>(1, 1, 1));
// .. create the vertical steering link between the spindle structure and the truss
link_steer_engineB = std::make_shared<ChLinkEngine>();
link_steer_engineB->Initialize(
spindleB, truss,
ChCoordsys<>(COG_wheelB, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_X))); // vertical axis
link_steer_engineB->Set_shaft_mode(ChLinkEngine::ENG_SHAFT_LOCK);
link_steer_engineB->Set_eng_mode(ChLinkEngine::ENG_MODE_ROTATION);
app->GetSystem()->AddLink(link_steer_engineB);
// ..the back wheel
wheelB = std::make_shared<ChBody>();
app->GetSystem()->Add(wheelB);
wheelB->SetPos(COG_wheelB);
wheelB->SetRot(chrono::Q_from_AngAxis(CH_C_PI, VECT_Y)); // reuse RF wheel shape, flipped
wheelB->SetMass(20);
wheelB->SetInertiaXX(ChVector<>(2, 2, 2));
// collision properties:
wheelB->GetCollisionModel()->ClearModel();
wheelB->GetCollisionModel()->AddCylinder(RAD_back_wheel, RAD_back_wheel, 0.1, ChVector<>(0, 0, 0), Arot);
wheelB->GetCollisionModel()->BuildModel();
wheelB->SetCollide(true);
// visualization properties:
auto wheelB_asset_assembly = std::make_shared<ChAssetLevel>();
wheelB_asset_assembly->GetFrame().SetPos(-COG_wheelRF);
wheelB->AddAsset(wheelB_asset_assembly);
auto wheelB_mesh = std::make_shared<ChObjShapeFile>();
wheelB_mesh->SetFilename(GetChronoDataFile("wheel.obj"));
wheelB_asset_assembly->AddAsset(wheelB_mesh);
auto wheelB_texture = std::make_shared<ChTexture>(GetChronoDataFile("tire_truck.png"));
wheelB_asset_assembly->AddAsset(wheelB_texture);
// .. create the motor between the back wheel and the steering spindle structure
link_engineB = std::make_shared<ChLinkEngine>();
link_engineB->Initialize(wheelB, spindleB,
ChCoordsys<>(COG_wheelB, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Y)));
link_engineB->Set_shaft_mode(ChLinkEngine::ENG_SHAFT_LOCK);
link_engineB->Set_eng_mode(ChLinkEngine::ENG_MODE_SPEED);
app->GetSystem()->AddLink(link_engineB);
// ..the arm
arm = std::make_shared<ChBody>();
app->GetSystem()->Add(arm);
arm->SetPos(COG_arm);
arm->SetMass(100);
arm->SetInertiaXX(ChVector<>(30, 30, 30));
// visualization properties:
auto arm_asset_assembly = std::make_shared<ChAssetLevel>();
arm_asset_assembly->GetFrame().SetPos(-COG_arm);
arm->AddAsset(arm_asset_assembly);
auto arm_mesh = std::make_shared<ChObjShapeFile>();
arm_mesh->SetFilename(GetChronoDataFile("forklift_arm.obj"));
arm_asset_assembly->AddAsset(arm_mesh);
// .. create the revolute joint between the arm and the truss
link_engineArm = std::make_shared<ChLinkEngine>(); // right, front, upper, 1
link_engineArm->Initialize(arm, truss,
ChCoordsys<>(POS_pivotarm, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Y)));
link_engineArm->Set_shaft_mode(ChLinkEngine::ENG_SHAFT_LOCK);
link_engineArm->Set_eng_mode(ChLinkEngine::ENG_MODE_ROTATION);
app->GetSystem()->AddLink(link_engineArm);
// ..the fork
fork = std::make_shared<ChBody>();
app->GetSystem()->Add(fork);
fork->SetPos(COG_fork);
fork->SetMass(60);
fork->SetInertiaXX(ChVector<>(15, 15, 15));
// collision properties:
fork->GetCollisionModel()->ClearModel();
fork->GetCollisionModel()->AddBox(0.1 / 2., 0.032 / 2., 1.033 / 2.,ChVector<>(-0.352, -0.312, 0.613));
fork->GetCollisionModel()->AddBox(0.1 / 2., 0.032 / 2., 1.033 / 2., ChVector<>(0.352, -0.312, 0.613));
fork->GetCollisionModel()->AddBox(0.344 / 2., 1.134 / 2., 0.101 / 2., ChVector<>(-0.000, 0.321, -0.009));
fork->GetCollisionModel()->BuildModel();
fork->SetCollide(true);
// visualization properties:
auto fork_asset_assembly = std::make_shared<ChAssetLevel>();
fork_asset_assembly->GetFrame().SetPos(-COG_fork);
fork->AddAsset(fork_asset_assembly);
auto fork_mesh = std::make_shared<ChObjShapeFile>();
fork_mesh->SetFilename(GetChronoDataFile("forklift_forks.obj"));
fork_asset_assembly->AddAsset(fork_mesh);
// .. create the prismatic joint between the fork and arm
link_prismaticFork = std::make_shared<ChLinkLockPrismatic>();
link_prismaticFork->Initialize(
fork, arm,
ChCoordsys<>(
POS_prismatic,
chrono::Q_from_AngAxis(CH_C_PI / 2,
VECT_X))); // set prism as vertical (default would be aligned to z, horizontal
app->GetSystem()->AddLink(link_prismaticFork);
// .. create the linear actuator that pushes upward the fork
link_actuatorFork = std::make_shared<ChLinkLinActuator>();
link_actuatorFork->Initialize(fork, arm, false,
ChCoordsys<>(POS_prismatic + ChVector<>(0, 0.01, 0), QUNIT),
ChCoordsys<>(POS_prismatic, QUNIT));
app->GetSystem()->AddLink(link_actuatorFork);
// ..a pallet
auto pallet = std::make_shared<ChBodyEasyMesh>(
GetChronoDataFile("pallet.obj"), // mesh .OBJ file
300, // density
true, // compute mass, inertia & COG from the mesh (must be a closed watertight mesh!)
true, // enable collision with mesh
0.001, // sphere swept inflate of mesh - improves robustness of collision detection
true); // enable visualization of mesh
app->GetSystem()->Add(pallet);
pallet->SetPos(ChVector<>(0, 0.4, 3));
// apply also a texture to the pallet:
auto pallet_texture = std::make_shared<ChTexture>();
pallet_texture->SetTextureFilename(GetChronoDataFile("cubetexture.png"));
pallet->AddAsset(pallet_texture);
//
// Move the forklift to initial offset position
//
// pallet->GetBody()->Move(offset);
truss->Move(offset);
wheelRF->Move(offset);
wheelLF->Move(offset);
wheelB->Move(offset);
spindleB->Move(offset);
arm->Move(offset);
fork->Move(offset);
}
// functions
TestMech(ChSystemNSC* system,
std::shared_ptr<ChBody> wheelBody,
double binWidth = 1.0,
double binLength = 2.0,
double weightMass = 100.0,
double springK = 25000,
double springD = 100) {
ChCollisionModel::SetDefaultSuggestedEnvelope(0.003);
ChCollisionModel::SetDefaultSuggestedMargin(0.002);
ChQuaternion<> rot;
rot.Q_from_AngAxis(ChRandom() * CH_C_2PI, VECT_Y);
// *******
// Create a soil bin with planes. bin width = x-dir, bin length = z-dir
// Note: soil bin depth will always be ~ 1m
// *******
double binHeight = 1.0;
double wallWidth = std::min<double>(binWidth, binLength) / 10.0; // wall width = 1/10 of min of bin dims
// create the floor
auto cubeMap = std::make_shared<ChTexture>();
cubeMap->SetTextureFilename(GetChronoDataFile("concrete.jpg"));
floor = std::make_shared<ChBodyEasyBox>(binWidth + wallWidth / 2.0, wallWidth, binLength + wallWidth / 2.0, 1.0, true, true);
floor->SetPos(ChVector<>(0, -0.5 - wallWidth / 2.0, 0));
floor->SetBodyFixed(true);
floor->GetMaterialSurfaceNSC()->SetFriction(0.5);
floor->AddAsset(cubeMap);
system->AddBody(floor);
// add some transparent walls to the soilBin, w.r.t. width, length of bin
wall1 = std::make_shared<ChBodyEasyBox>(wallWidth, binHeight, binLength, 1.0, true, true);
wall1->SetPos(ChVector<>(-binWidth / 2.0 - wallWidth / 2.0, 0, 0));
wall1->SetBodyFixed(true);
system->AddBody(wall1);
wall2 = std::make_shared<ChBodyEasyBox>(wallWidth, binHeight, binLength, 1.0, true, false);
wall2->SetPos(ChVector<>(binWidth / 2.0 + wallWidth / 2.0, 0, 0));
wall2->SetBodyFixed(true);
system->AddBody(wall2);
wall3 = std::make_shared<ChBodyEasyBox>(binWidth + wallWidth / 2.0, binHeight, wallWidth, 1.0, true, false);
wall3->SetPos(ChVector<>(0, 0, -binLength / 2.0 - wallWidth / 2.0));
wall3->SetBodyFixed(true);
system->AddBody(wall3);
// wall 4
wall4 = std::make_shared<ChBodyEasyBox>(binWidth + wallWidth / 2.0, binHeight, wallWidth, 1.0, true, true);
wall4->SetPos(ChVector<>(0, 0, binLength / 2.0 + wallWidth / 2.0));
wall4->SetBodyFixed(true);
system->AddBody(wall4);
// ******
// make a truss, connect it to the wheel via revolute joint
// single rotational DOF will be driven with a user-input for torque
// *****
auto bluMap = std::make_shared<ChTexture>();
bluMap->SetTextureFilename(GetChronoDataFile("blu.png"));
ChVector<> trussCM = wheelBody->GetPos();
truss = std::make_shared<ChBodyEasyBox>(0.2, 0.2, 0.4, 300.0, false, true);
truss->SetPos(trussCM);
truss->SetMass(5.0);
truss->AddAsset(bluMap);
system->AddBody(truss);
// create the revolute joint between the wheel and spindle
spindle = std::make_shared<ChLinkLockRevolute>();
spindle->Initialize(truss, wheelBody, ChCoordsys<>(trussCM, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Y)));
system->AddLink(spindle);
// create a torque between the truss and wheel
torqueDriver = std::make_shared<ChLinkEngine>();
torqueDriver->Initialize(truss, wheelBody, ChCoordsys<>(trussCM, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_Y)));
torqueDriver->Set_eng_mode(ChLinkEngine::ENG_MODE_TORQUE);
system->AddLink(torqueDriver);
// ******
// create a body that will be used as a vehicle weight
ChVector<> weightCM = ChVector<>(trussCM);
weightCM.y() += 1.0; // note: this will determine the spring free length
suspweight = std::make_shared<ChBodyEasyBox>(0.2, 0.4, 0.2, 5000.0, false, true);
suspweight->SetPos(weightCM);
suspweight->SetMass(weightMass);
suspweight->AddAsset(bluMap);
system->AddBody(suspweight);
// create the translational joint between the truss and weight load
auto translational = std::make_shared<ChLinkLockPrismatic>();
translational->Initialize(truss, suspweight,
ChCoordsys<>(trussCM, chrono::Q_from_AngAxis(CH_C_PI / 2, VECT_X)));
system->AddLink(translational);
// create a spring between spindle truss and weight
spring = std::make_shared<ChLinkSpring>();
spring->Initialize(truss, suspweight, false, trussCM, suspweight->GetPos());
spring->Set_SpringK(springK);
spring->Set_SpringR(springD);
system->AddLink(spring);
// create a prismatic constraint between the weight and the ground
auto weightLink = std::make_shared<ChLinkLockOldham>();
weightLink->Initialize(suspweight, floor,
ChCoordsys<>(weightCM, chrono::Q_from_AngAxis(CH_C_PI / 2.0, VECT_Y)));
system->AddLink(weightLink);
}