pxmlw6n2f/Gazebo_Distributed_TCP/gazebo/physics/Inertial.cc

440 lines
12 KiB
C++

/*
* Copyright (C) 2012 Open Source Robotics Foundation
*
* 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.
*
*/
#include <boost/bind.hpp>
#include "gazebo/physics/Inertial.hh"
using namespace gazebo;
using namespace physics;
sdf::ElementPtr Inertial::sdfInertial;
//////////////////////////////////////////////////
Inertial::Inertial()
{
this->mass = 1;
this->principals.Set(1, 1, 1);
this->products.Set(0, 0, 0);
if (!this->sdfInertial)
{
this->sdfInertial.reset(new sdf::Element);
initFile("inertial.sdf", this->sdfInertial);
}
// This is the only time this->sdfInertial should be used.
this->sdf = this->sdfInertial->Clone();
}
//////////////////////////////////////////////////
Inertial::Inertial(double _m)
{
this->sdf.reset(new sdf::Element);
initFile("inertial.sdf", this->sdf);
this->mass = _m;
this->cog.Set(0, 0, 0, 0, 0, 0);
this->principals.Set(1, 1, 1);
this->products.Set(0, 0, 0);
}
//////////////////////////////////////////////////
Inertial::Inertial(const ignition::math::Inertiald &_inertial)
{
this->sdf.reset(new sdf::Element);
initFile("inertial.sdf", this->sdf);
this->SetMass(_inertial.MassMatrix().Mass());
this->SetCoG(_inertial.Pose());
this->SetInertiaMatrix(
_inertial.MassMatrix().IXX(),
_inertial.MassMatrix().IYY(),
_inertial.MassMatrix().IZZ(),
_inertial.MassMatrix().IXY(),
_inertial.MassMatrix().IXZ(),
_inertial.MassMatrix().IYZ());
}
//////////////////////////////////////////////////
Inertial::Inertial(const Inertial &_inertial)
{
this->sdf.reset(new sdf::Element);
initFile("inertial.sdf", this->sdf);
(*this) = _inertial;
}
//////////////////////////////////////////////////
Inertial::~Inertial()
{
this->sdf.reset();
}
//////////////////////////////////////////////////
void Inertial::Load(sdf::ElementPtr _sdf)
{
this->UpdateParameters(_sdf);
}
//////////////////////////////////////////////////
void Inertial::UpdateParameters(sdf::ElementPtr _sdf)
{
this->sdf = _sdf;
// use default pose (identity) if not specified in sdf
math::Pose pose = this->sdf->Get<math::Pose>("pose");
this->SetCoG(pose);
// if (this->sdf->HasElement("inertia"))
// Do the following whether an inertia element was specified or not.
// Otherwise SetUpdateFunc won't get called.
{
sdf::ElementPtr inertiaElem = this->sdf->GetElement("inertia");
this->SetInertiaMatrix(
inertiaElem->Get<double>("ixx"),
inertiaElem->Get<double>("iyy"),
inertiaElem->Get<double>("izz"),
inertiaElem->Get<double>("ixy"),
inertiaElem->Get<double>("ixz"),
inertiaElem->Get<double>("iyz"));
inertiaElem->GetElement("ixx")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetIXX, this));
inertiaElem->GetElement("iyy")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetIYY, this));
inertiaElem->GetElement("izz")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetIZZ, this));
inertiaElem->GetElement("ixy")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetIXY, this));
inertiaElem->GetElement("ixz")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetIXZ, this));
inertiaElem->GetElement("iyz")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetIYZ, this));
}
this->SetMass(this->sdf->Get<double>("mass"));
this->sdf->GetElement("mass")->GetValue()->SetUpdateFunc(
boost::bind(&Inertial::GetMass, this));
}
//////////////////////////////////////////////////
Inertial Inertial::GetInertial(const math::Pose &_frameOffset) const
{
// make a copy of the current Inertial
Inertial result(*this);
// new CoG location after link frame offset
result.cog = result.cog - _frameOffset;
// new MOI after link frame offset
result.SetMOI(this->GetMOI(result.cog));
return result;
}
//////////////////////////////////////////////////
void Inertial::Reset()
{
sdf::ElementPtr inertiaElem = this->sdf->GetElement("inertia");
this->mass = this->sdf->Get<double>("mass");
this->cog.Set(0, 0, 0, 0, 0, 0);
this->SetInertiaMatrix(
inertiaElem->Get<double>("ixx"),
inertiaElem->Get<double>("iyy"),
inertiaElem->Get<double>("izz"),
inertiaElem->Get<double>("ixy"),
inertiaElem->Get<double>("ixz"),
inertiaElem->Get<double>("iyz"));
}
//////////////////////////////////////////////////
void Inertial::SetMass(double _m)
{
this->mass = _m;
}
//////////////////////////////////////////////////
double Inertial::GetMass() const
{
return this->mass;
}
//////////////////////////////////////////////////
void Inertial::SetCoG(double _cx, double _cy, double _cz)
{
this->cog.pos.Set(_cx, _cy, _cz);
}
//////////////////////////////////////////////////
void Inertial::SetCoG(const math::Vector3 &_c)
{
this->cog.pos = _c;
}
//////////////////////////////////////////////////
void Inertial::SetCoG(double _cx, double _cy, double _cz,
double _rx, double _ry, double _rz)
{
this->cog.Set(_cx, _cy, _cz, _rx, _ry, _rz);
}
//////////////////////////////////////////////////
void Inertial::SetCoG(const math::Pose &_c)
{
this->cog = _c;
}
//////////////////////////////////////////////////
void Inertial::SetInertiaMatrix(double ixx, double iyy, double izz,
double ixy, double ixz, double iyz)
{
this->principals.Set(ixx, iyy, izz);
this->products.Set(ixy, ixz, iyz);
}
//////////////////////////////////////////////////
math::Vector3 Inertial::GetPrincipalMoments() const
{
return this->principals;
}
//////////////////////////////////////////////////
math::Vector3 Inertial::GetProductsofInertia() const
{
return this->products;
}
//////////////////////////////////////////////////
void Inertial::SetMOI(const math::Matrix3 &_moi)
{
/// \TODO: check symmetry of incoming _moi matrix
this->principals.Set(_moi[0][0], _moi[1][1], _moi[2][2]);
this->products.Set(_moi[0][1], _moi[0][2], _moi[1][2]);
}
//////////////////////////////////////////////////
math::Matrix3 Inertial::GetMOI() const
{
return math::Matrix3(
this->principals.x, this->products.x, this->products.y,
this->products.x, this->principals.y, this->products.z,
this->products.y, this->products.z, this->principals.z);
}
//////////////////////////////////////////////////
void Inertial::Rotate(const math::Quaternion &_rot)
{
/// \TODO: double check what this does, if needed
this->cog.pos = _rot.RotateVector(this->cog.pos);
this->cog.rot = _rot * this->cog.rot;
}
//////////////////////////////////////////////////
Inertial &Inertial::operator=(const Inertial &_inertial)
{
this->mass = _inertial.mass;
this->cog = _inertial.cog;
this->principals = _inertial.principals;
this->products = _inertial.products;
return *this;
}
//////////////////////////////////////////////////
Inertial Inertial::operator+(const Inertial &_inertial) const
{
Inertial result(*this);
// update mass with sum
result.mass = this->mass + _inertial.mass;
// compute new center of mass
result.cog.pos =
(this->cog.pos*this->mass + _inertial.cog.pos * _inertial.mass) /
result.mass;
// make a decision on the new orientation, set it to identity
result.cog.rot = math::Quaternion(1, 0, 0, 0);
// compute equivalent I for (*this) at the new CoG
math::Matrix3 Ithis = this->GetMOI(result.cog);
// compute equivalent I for _inertial at the new CoG
math::Matrix3 Iparam = _inertial.GetMOI(result.cog);
// sum up principals and products now they are at the same location
result.SetMOI(Ithis + Iparam);
return result;
}
//////////////////////////////////////////////////
math::Matrix3 Inertial::GetMOI(const math::Pose &_pose) const
{
// get MOI as a Matrix3
math::Matrix3 moi = this->GetMOI();
// transform from new _pose to old this->cog, specified in new _pose frame
math::Pose new2Old = this->cog - _pose;
// rotate moi into new cog frame
moi = new2Old.rot.GetAsMatrix3() * moi *
new2Old.rot.GetInverse().GetAsMatrix3();
// parallel axis theorem to get MOI at the new cog location
// integrating point mass at some offset
math::Vector3 offset = new2Old.pos;
moi[0][0] += (offset.y * offset.y + offset.z * offset.z) * this->mass;
moi[0][1] -= (offset.x * offset.y) * this->mass;
moi[0][2] -= (offset.x * offset.z) * this->mass;
moi[1][0] -= (offset.y * offset.x) * this->mass;
moi[1][1] += (offset.x * offset.x + offset.z * offset.z) * this->mass;
moi[1][2] -= (offset.y * offset.z) * this->mass;
moi[2][0] -= (offset.z * offset.x) * this->mass;
moi[2][1] -= (offset.z * offset.y) * this->mass;
moi[2][2] += (offset.x * offset.x + offset.y * offset.y) * this->mass;
return moi;
}
//////////////////////////////////////////////////
const Inertial &Inertial::operator+=(const Inertial &_inertial)
{
*this = *this + _inertial;
return *this;
}
//////////////////////////////////////////////////
double Inertial::GetIXX() const
{
return this->principals.x;
}
//////////////////////////////////////////////////
double Inertial::GetIYY() const
{
return this->principals.y;
}
//////////////////////////////////////////////////
double Inertial::GetIZZ() const
{
return this->principals.z;
}
//////////////////////////////////////////////////
double Inertial::GetIXY() const
{
return this->products.x;
}
//////////////////////////////////////////////////
double Inertial::GetIXZ() const
{
return this->products.y;
}
//////////////////////////////////////////////////
double Inertial::GetIYZ() const
{
return this->products.z;
}
//////////////////////////////////////////////////
void Inertial::SetIXX(double _v)
{
this->principals.x = _v;
}
//////////////////////////////////////////////////
void Inertial::SetIYY(double _v)
{
this->principals.y = _v;
}
//////////////////////////////////////////////////
void Inertial::SetIZZ(double _v)
{
this->principals.z = _v;
}
//////////////////////////////////////////////////
void Inertial::SetIXY(double _v)
{
this->products.x = _v;
}
//////////////////////////////////////////////////
void Inertial::SetIXZ(double _v)
{
this->products.y = _v;
}
//////////////////////////////////////////////////
void Inertial::SetIYZ(double _v)
{
this->products.z = _v;
}
//////////////////////////////////////////////////
void Inertial::ProcessMsg(const msgs::Inertial &_msg)
{
if (_msg.has_mass())
this->SetMass(_msg.mass());
if (_msg.has_pose())
this->SetCoG(_msg.pose().position().x(),
_msg.pose().position().y(),
_msg.pose().position().z());
if (_msg.has_ixx())
this->SetIXX(_msg.ixx());
if (_msg.has_ixy())
this->SetIXY(_msg.ixy());
if (_msg.has_ixz())
this->SetIXZ(_msg.ixz());
if (_msg.has_iyy())
this->SetIYY(_msg.iyy());
if (_msg.has_iyz())
this->SetIYZ(_msg.iyz());
if (_msg.has_izz())
this->SetIZZ(_msg.izz());
}
//////////////////////////////////////////////////
ignition::math::Inertiald Inertial::Ign() const
{
return ignition::math::Inertiald(
ignition::math::MassMatrix3d(
this->GetMass(),
this->GetPrincipalMoments().Ign(),
this->GetProductsofInertia().Ign()),
this->cog.Ign());
}
//////////////////////////////////////////////////
Inertial &Inertial::operator=(const ignition::math::Inertiald &_inertial)
{
this->mass = _inertial.MassMatrix().Mass();
this->cog = _inertial.Pose();
this->principals = _inertial.MassMatrix().DiagonalMoments();
this->products = _inertial.MassMatrix().OffDiagonalMoments();
return *this;
}