Scene.cpp

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/*
 * Scene.cpp
 *
 *  Created on: Jan 5, 2009
 *      Author: rubensmits
 */

#include "Scene.hpp"
#include "ControlledObject.hpp"
#include "kdl/utilities/svd_eigen_HH.hpp"
#include <cstdio>

namespace iTaSC {

class SceneLock : public ControlledObject::JointLockCallback {
private:
    Scene* m_scene;
    Range  m_qrange;

public:
    SceneLock(Scene* scene) :
      m_scene(scene), m_qrange(0,0) {}
    virtual ~SceneLock() {}

    void setRange(Range& range)
    {
        m_qrange = range;
    }
    // lock a joint, no need to update output
    virtual void lockJoint(unsigned int q_nr, unsigned int ndof)
    {
        q_nr += m_qrange.start;
        project(m_scene->m_Wq, Range(q_nr, ndof), m_qrange).setZero();
    }
    // lock a joint and update output in view of reiteration
    virtual void lockJoint(unsigned int q_nr, unsigned int ndof, double* qdot)
    {
        q_nr += m_qrange.start;
        project(m_scene->m_Wq, Range(q_nr, ndof), m_qrange).setZero();
        // update the ouput vector so that the movement of this joint will be 
        // taken into account and we can put the joint back in its initial position
        // which means that the jacobian doesn't need to be changed
        for (unsigned int i=0 ;i<ndof ; ++i, ++q_nr) {
            m_scene->m_ydot -= m_scene->m_A.col(q_nr)*qdot[i];
        }
    }
};

Scene::Scene():
    m_A(), m_B(), m_Atemp(), m_Wq(), m_Jf(), m_Jq(), m_Ju(), m_Cf(), m_Cq(), m_Jf_inv(),
    m_Vf(),m_Uf(), m_Wy(), m_ydot(), m_qdot(), m_xdot(), m_Sf(),m_tempf(),
    m_ncTotal(0),m_nqTotal(0),m_nuTotal(0),m_nsets(0),
    m_solver(NULL),m_cache(NULL) 
{
    m_minstep = 0.01;
    m_maxstep = 0.06;
}

Scene::~Scene() 
{
    ConstraintMap::iterator constraint_it;
    while ((constraint_it = constraints.begin()) != constraints.end()) {
        delete constraint_it->second;
        constraints.erase(constraint_it);
    }
    ObjectMap::iterator object_it;
    while ((object_it = objects.begin()) != objects.end()) {
        delete object_it->second;
        objects.erase(object_it);
    }
}

bool Scene::setParam(SceneParam paramId, double value)
{
    switch (paramId) {
    case MIN_TIMESTEP:
        m_minstep = value;
        break;
    case MAX_TIMESTEP:      
        m_maxstep = value;
        break;
    default:
        return false;
    }
    return true;
}

bool Scene::addObject(const std::string& name, Object* object, UncontrolledObject* base, const std::string& baseFrame)
{
    // finalize the object before adding
    object->finalize();
    //Check if Object is controlled or uncontrolled.
    if(object->getType()==Object::Controlled){
        int baseFrameIndex = base->addEndEffector(baseFrame);
        if (baseFrameIndex < 0)
            return false;
        std::pair<ObjectMap::iterator, bool> result;
        if (base->getNrOfCoordinates() == 0) {
            // base is fixed object, no coordinate range
            result = objects.insert(ObjectMap::value_type(
                    name, new Object_struct(object,base,baseFrameIndex,
                        Range(m_nqTotal,object->getNrOfCoordinates()),
                        Range(m_ncTotal,((ControlledObject*)object)->getNrOfConstraints()),
                        Range(0,0))));
        } else {
            // base is a moving object, must be in list already
            ObjectMap::iterator base_it;
            for (base_it=objects.begin(); base_it != objects.end(); base_it++) {
                if (base_it->second->object == base)
                    break;
            }
            if (base_it == objects.end())
                return false;
            result = objects.insert(ObjectMap::value_type(
                    name, new Object_struct(object,base,baseFrameIndex,
                        Range(m_nqTotal,object->getNrOfCoordinates()),
                        Range(m_ncTotal,((ControlledObject*)object)->getNrOfConstraints()),
                        base_it->second->coordinaterange)));
        }
        if (!result.second) {
            return false;
        }
        m_nqTotal+=object->getNrOfCoordinates();
        m_ncTotal+=((ControlledObject*)object)->getNrOfConstraints();
        return true;
    }
    if(object->getType()==Object::UnControlled){
        if ((WorldObject*)base != &Object::world)
            return false;
        std::pair<ObjectMap::iterator,bool> result = objects.insert(ObjectMap::value_type(
            name,new Object_struct(object,base,0,
                        Range(0,0),
                        Range(0,0),
                        Range(m_nuTotal,object->getNrOfCoordinates()))));
        if(!result.second)
            return false;
        m_nuTotal+=object->getNrOfCoordinates();
        return true;
    }
    return false;
}

bool Scene::addConstraintSet(const std::string& name,ConstraintSet* task,const std::string& object1,const std::string& object2, const std::string& ee1, const std::string& ee2)
{
    //Check if objects exist:
    ObjectMap::iterator object1_it = objects.find(object1);
    ObjectMap::iterator object2_it = objects.find(object2);
    if(object1_it==objects.end()||object2_it==objects.end())
        return false;
    int ee1_index = object1_it->second->object->addEndEffector(ee1);
    int ee2_index = object2_it->second->object->addEndEffector(ee2);
    if (ee1_index < 0 || ee2_index < 0)
        return false;
    std::pair<ConstraintMap::iterator,bool> result = 
        constraints.insert(ConstraintMap::value_type(name,new ConstraintSet_struct(
            task,object1_it,ee1_index,object2_it,ee2_index,
            Range(m_ncTotal,task->getNrOfConstraints()),Range(6*m_nsets,6))));
    if(!result.second)
        return false;
    m_ncTotal+=task->getNrOfConstraints();
    m_nsets+=1;
    return true;
}

bool Scene::addSolver(Solver* _solver){
    if(m_solver==NULL){
        m_solver=_solver;
        return true;
    }
    else
        return false;
}

bool Scene::addCache(Cache* _cache){
    if(m_cache==NULL){
        m_cache=_cache;
        return true;
    }
    else
        return false;
}

bool Scene::initialize(){

    //prepare all matrices:
    if (m_ncTotal == 0 || m_nqTotal == 0 || m_nsets == 0)
        return false;

    m_A = e_zero_matrix(m_ncTotal,m_nqTotal);
    if (m_nuTotal > 0) {
        m_B = e_zero_matrix(m_ncTotal,m_nuTotal);
        m_xdot = e_zero_vector(m_nuTotal);
        m_Ju = e_zero_matrix(6*m_nsets,m_nuTotal);
    }
    m_Atemp = e_zero_matrix(m_ncTotal,6*m_nsets);
    m_ydot = e_zero_vector(m_ncTotal);
    m_qdot = e_zero_vector(m_nqTotal);
    m_Wq = e_zero_matrix(m_nqTotal,m_nqTotal);
    m_Wy = e_zero_vector(m_ncTotal);
    m_Jq = e_zero_matrix(6*m_nsets,m_nqTotal);
    m_Jf = e_zero_matrix(6*m_nsets,6*m_nsets);
    m_Jf_inv = m_Jf;
    m_Cf = e_zero_matrix(m_ncTotal,m_Jf.rows());
    m_Cq = e_zero_matrix(m_ncTotal,m_nqTotal);

    bool result=true;
    // finalize all objects
    for (ObjectMap::iterator it=objects.begin(); it!=objects.end(); ++it) {
        Object_struct* os = it->second;

        os->object->initCache(m_cache);
        if (os->constraintrange.count > 0)
            project(m_Cq,os->constraintrange,os->jointrange) = (((ControlledObject*)(os->object))->getCq());
    }

    m_ytask.resize(m_ncTotal);
    bool toggle=true;
    int cnt = 0;
    //Initialize all ConstraintSets:
    for(ConstraintMap::iterator it=constraints.begin();it!=constraints.end();++it){
        //Calculate the external pose:
        ConstraintSet_struct* cs = it->second;
        Frame external_pose;
        getConstraintPose(cs->task, cs, external_pose);
        result&=cs->task->initialise(external_pose);
        cs->task->initCache(m_cache);
        for (int i=0; i<cs->constraintrange.count; i++, cnt++) {
            m_ytask[cnt] = toggle;
        }
        toggle = !toggle;
        project(m_Cf,cs->constraintrange,cs->featurerange)=cs->task->getCf();
    }

    if(m_solver!=NULL)
        m_solver->init(m_nqTotal,m_ncTotal,m_ytask);
    else
        return false;


    return result;
}

bool Scene::getConstraintPose(ConstraintSet* constraint, void *_param, KDL::Frame& _pose)
{
    // function called from constraint when they need to get the external pose
    ConstraintSet_struct* cs = (ConstraintSet_struct*)_param;
    // verification, the pointer MUST match
    assert (constraint == cs->task);
    Object_struct* ob1 = cs->object1->second;
    Object_struct* ob2 = cs->object2->second;
    //Calculate the external pose:
    _pose=(ob1->base->getPose(ob1->baseFrameIndex)*ob1->object->getPose(cs->ee1index)).Inverse()*(ob2->base->getPose(ob2->baseFrameIndex)*ob2->object->getPose(cs->ee2index));
    return true;
}

bool Scene::update(double timestamp, double timestep, unsigned int numsubstep, bool reiterate, bool cache, bool interpolate)
{
    // we must have valid timestep and timestamp
    if (timestamp < KDL::epsilon || timestep < 0.0)
        return false;
    Timestamp ts;
    ts.realTimestamp = timestamp;
    // initially we start with the full timestep to allow velocity estimation over the full interval
    ts.realTimestep = timestep;
    setCacheTimestamp(ts);
    ts.substep = 0;
    // for reiteration don't load cache
    // reiteration=additional iteration with same timestamp if application finds the convergence not good enough
    ts.reiterate = (reiterate) ? 1 : 0;
    ts.interpolate = (interpolate) ? 1 : 0;
    ts.cache = (cache) ? 1 : 0;
    ts.update = 1;
    ts.numstep = (numsubstep & 0xFF);
    bool autosubstep = (numsubstep == 0) ? true : false;
    if (numsubstep < 1)
        numsubstep = 1;
    double timesubstep = timestep/numsubstep;
    double timeleft = timestep;

    if (timeleft == 0.0) {
        // this special case correspond to a request to cache data
        for(ObjectMap::iterator it=objects.begin();it!=objects.end();++it){
            it->second->object->pushCache(ts);
        }
        //Update the Constraints
        for(ConstraintMap::iterator it=constraints.begin();it!=constraints.end();++it){
            it->second->task->pushCache(ts);
        }
        return true;
    }

    // double maxqdot; // UNUSED
    e_scalar nlcoef;
    SceneLock lockCallback(this);
    Frame external_pose;
    bool locked;

    // initially we keep timestep unchanged so that update function compute the velocity over
    while (numsubstep > 0) {
        // get objects
        for(ObjectMap::iterator it=objects.begin();it!=objects.end();++it) {
            Object_struct* os = it->second;
            if (os->object->getType()==Object::Controlled) {
                ((ControlledObject*)(os->object))->updateControlOutput(ts);
                if (os->constraintrange.count > 0) {
                    project(m_ydot, os->constraintrange) = ((ControlledObject*)(os->object))->getControlOutput();
                    project(m_Wy, os->constraintrange) = ((ControlledObject*)(os->object))->getWy();
                    // project(m_Cq,os->constraintrange,os->jointrange) = (((ControlledObject*)(os->object))->getCq());
                }
                if (os->jointrange.count > 0) {
                    project(m_Wq,os->jointrange,os->jointrange) = ((ControlledObject*)(os->object))->getWq();
                }
            }
            if (os->object->getType()==Object::UnControlled && ((UncontrolledObject*)os->object)->getNrOfCoordinates() != 0) {
                ((UncontrolledObject*)(os->object))->updateCoordinates(ts);
                if (!ts.substep) {
                    // velocity of uncontrolled object remains constant during substepping
                    project(m_xdot,os->coordinaterange) = ((UncontrolledObject*)(os->object))->getXudot();
                }
            }
        }

        //get new Constraints values
        for(ConstraintMap::iterator it=constraints.begin();it!=constraints.end();++it) {
            ConstraintSet_struct* cs = it->second;
            Object_struct* ob1 = cs->object1->second;
            Object_struct* ob2 = cs->object2->second;

            if (ob1->base->updated() || ob1->object->updated() || ob2->base->updated() || ob2->object->updated()) {
                // the object from which the constraint depends have changed position
                // recompute the constraint pose
                getConstraintPose(cs->task, cs, external_pose);
                cs->task->initialise(external_pose);
            }
            cs->task->updateControlOutput(ts);
            project(m_ydot,cs->constraintrange)=cs->task->getControlOutput();
            if (!ts.substep || cs->task->substep()) {
                project(m_Wy,cs->constraintrange)=(cs->task)->getWy();
                //project(m_Cf,cs->constraintrange,cs->featurerange)=cs->task->getCf();
            }

            project(m_Jf,cs->featurerange,cs->featurerange)=cs->task->getJf();
            //std::cout << "Jf = " << Jf << std::endl;
            //Transform the reference frame of this jacobian to the world reference frame
            Eigen::Block<e_matrix> Jf_part = project(m_Jf,cs->featurerange,cs->featurerange);
            changeBase(Jf_part,ob1->base->getPose(ob1->baseFrameIndex)*ob1->object->getPose(cs->ee1index));
            //std::cout << "Jf_w = " << Jf << std::endl;

            //calculate the inverse of Jf
            KDL::svd_eigen_HH(project(m_Jf,cs->featurerange,cs->featurerange),m_Uf,m_Sf,m_Vf,m_tempf);
            for(unsigned int i=0;i<6;++i)
                if(m_Sf(i)<KDL::epsilon)
                    m_Uf.col(i).setConstant(0.0);
                else
                    m_Uf.col(i)*=(1/m_Sf(i));
            project(m_Jf_inv,cs->featurerange,cs->featurerange).noalias()=m_Vf*m_Uf.transpose();

            //Get the robotjacobian associated with this constraintset
            //Each jacobian is expressed in robot base frame => convert to world reference
            //and negate second robot because it is taken reversed when closing the loop:
            if(ob1->object->getType()==Object::Controlled){
                project(m_Jq,cs->featurerange,ob1->jointrange) = (((ControlledObject*)(ob1->object))->getJq(cs->ee1index));
                //Transform the reference frame of this jacobian to the world reference frame:
                Eigen::Block<e_matrix> Jq_part = project(m_Jq,cs->featurerange,ob1->jointrange);
                changeBase(Jq_part,ob1->base->getPose(ob1->baseFrameIndex));
                // if the base of this object is moving, get the Ju part
                if (ob1->base->getNrOfCoordinates() != 0) {
                    // Ju is already computed for world reference frame
                    project(m_Ju,cs->featurerange,ob1->coordinaterange)=ob1->base->getJu(ob1->baseFrameIndex);
                }
            } else if (ob1->object->getType() == Object::UnControlled && ((UncontrolledObject*)ob1->object)->getNrOfCoordinates() != 0) {
                // object1 is uncontrolled moving object
                project(m_Ju,cs->featurerange,ob1->coordinaterange)=((UncontrolledObject*)ob1->object)->getJu(cs->ee1index);
            }
            if(ob2->object->getType()==Object::Controlled){
                //Get the robotjacobian associated with this constraintset
                // process a special case where object2 and object1 are equal but using different end effector
                if (ob1->object == ob2->object) {
                    // we must create a temporary matrix
                    e_matrix JqTemp(((ControlledObject*)(ob2->object))->getJq(cs->ee2index));
                    //Transform the reference frame of this jacobian to the world reference frame:
                    changeBase(JqTemp,ob2->base->getPose(ob2->baseFrameIndex));
                    // substract in place
                    project(m_Jq,cs->featurerange,ob2->jointrange) -= JqTemp;
                } else {
                    project(m_Jq,cs->featurerange,ob2->jointrange) = -(((ControlledObject*)(ob2->object))->getJq(cs->ee2index));
                    //Transform the reference frame of this jacobian to the world reference frame:
                    Eigen::Block<e_matrix> Jq_part = project(m_Jq,cs->featurerange,ob2->jointrange);
                    changeBase(Jq_part,ob2->base->getPose(ob2->baseFrameIndex));
                }
                if (ob2->base->getNrOfCoordinates() != 0) {
                    // if base is the same as first object or first object base, 
                    // that portion of m_Ju has been set already => substract inplace
                    if (ob2->base == ob1->base || ob2->base == ob1->object) {
                        project(m_Ju,cs->featurerange,ob2->coordinaterange) -= ob2->base->getJu(ob2->baseFrameIndex);
                    } else {
                        project(m_Ju,cs->featurerange,ob2->coordinaterange) = -ob2->base->getJu(ob2->baseFrameIndex);
                    }
                }
            } else if (ob2->object->getType() == Object::UnControlled && ((UncontrolledObject*)ob2->object)->getNrOfCoordinates() != 0) {
                if (ob2->object == ob1->base || ob2->object == ob1->object) {
                    project(m_Ju,cs->featurerange,ob2->coordinaterange) -= ((UncontrolledObject*)ob2->object)->getJu(cs->ee2index);
                } else {
                    project(m_Ju,cs->featurerange,ob2->coordinaterange) = -((UncontrolledObject*)ob2->object)->getJu(cs->ee2index);
                }
            }
        }

        //Calculate A
        m_Atemp.noalias()=m_Cf*m_Jf_inv;
        m_A.noalias() = m_Cq-(m_Atemp*m_Jq);
        if (m_nuTotal > 0) {
            m_B.noalias()=m_Atemp*m_Ju;
            m_ydot.noalias() += m_B*m_xdot;
        }

        //Call the solver with A, Wq, Wy, ydot to solver qdot:
        if(!m_solver->solve(m_A,m_Wy,m_ydot,m_Wq,m_qdot,nlcoef))
            // this should never happen
            return false;
        //send result to the objects
        for(ObjectMap::iterator it=objects.begin();it!=objects.end();++it) {
            Object_struct* os = it->second;
            if(os->object->getType()==Object::Controlled)
                ((ControlledObject*)(os->object))->setJointVelocity(project(m_qdot,os->jointrange));
        }
        // compute the constraint velocity
        for(ConstraintMap::iterator it=constraints.begin();it!=constraints.end();++it){
            ConstraintSet_struct* cs = it->second;
            Object_struct* ob1 = cs->object1->second;
            Object_struct* ob2 = cs->object2->second;
            //Calculate the twist of the world reference frame due to the robots (Jq*qdot+Ju*chiudot):
            e_vector6 external_vel = e_zero_vector(6);
            if (ob1->jointrange.count > 0)
                external_vel.noalias() += (project(m_Jq,cs->featurerange,ob1->jointrange)*project(m_qdot,ob1->jointrange));
            if (ob2->jointrange.count > 0)
                external_vel.noalias() += (project(m_Jq,cs->featurerange,ob2->jointrange)*project(m_qdot,ob2->jointrange));
            if (ob1->coordinaterange.count > 0)
                external_vel.noalias() += (project(m_Ju,cs->featurerange,ob1->coordinaterange)*project(m_xdot,ob1->coordinaterange));
            if (ob2->coordinaterange.count > 0)
                external_vel.noalias() += (project(m_Ju,cs->featurerange,ob2->coordinaterange)*project(m_xdot,ob2->coordinaterange));
            //the twist caused by the constraint must be opposite because of the closed loop
            //estimate the velocity of the joints using the inverse jacobian
            e_vector6 estimated_chidot = project(m_Jf_inv,cs->featurerange,cs->featurerange)*(-external_vel);
            cs->task->setJointVelocity(estimated_chidot);
        }

        if (autosubstep) {
            // automatic computing of substep based on maximum joint change
            // and joint limit gain variation
            // We will pass the joint velocity to each object and they will recommend a maximum timestep
            timesubstep = timeleft;
            // get armature max joint velocity to estimate the maximum duration of integration
            // maxqdot = m_qdot.cwise().abs().maxCoeff(); // UNUSED
            double maxsubstep = nlcoef*m_maxstep;
            if (maxsubstep < m_minstep)
                maxsubstep = m_minstep;
            if (timesubstep > maxsubstep)
                timesubstep = maxsubstep;
            for(ObjectMap::iterator it=objects.begin();it!=objects.end();++it){
                Object_struct* os = it->second;
                if(os->object->getType()==Object::Controlled)
                    ((ControlledObject*)(os->object))->getMaxTimestep(timesubstep);
            }
            for(ConstraintMap::iterator it=constraints.begin();it!=constraints.end();++it){
                ConstraintSet_struct* cs = it->second;
                cs->task->getMaxTimestep(timesubstep);
            }
            // use substep that are even dividers of timestep for more regularity
            maxsubstep = 2.0*floor(timestep/2.0/timesubstep-0.66666);
            timesubstep = (maxsubstep < 0.0) ? timestep : timestep/(2.0+maxsubstep);
            if (timesubstep >= timeleft-(m_minstep/2.0)) {
                timesubstep = timeleft;
                numsubstep = 1;
                timeleft = 0.;
            } else {
                numsubstep = 2;
                timeleft -= timesubstep;
            }
        }
        if (numsubstep > 1) {
            ts.substep = 1;
        } else {
            // set substep to false for last iteration so that controlled output 
            // can be updated in updateKinematics() and model_update)() before next call to Secne::update()
            ts.substep = 0;
        }
        // change timestep so that integration is done correctly
        ts.realTimestep = timesubstep;

        do {
            ObjectMap::iterator it;
            Object_struct* os;
            locked = false;
            for(it=objects.begin();it!=objects.end();++it){
                os = it->second;
                if (os->object->getType()==Object::Controlled) {
                    lockCallback.setRange(os->jointrange);
                    if (((ControlledObject*)os->object)->updateJoint(ts, lockCallback)) {
                        // this means one of the joint was locked and we must rerun
                        // the solver to update the remaining joints
                        locked = true;
                        break;
                    }
                }
            }
            if (locked) {
                // Some rows of m_Wq have been cleared so that the corresponding joint will not move
                if(!m_solver->solve(m_A,m_Wy,m_ydot,m_Wq,m_qdot,nlcoef))
                    // this should never happen
                    return false;

                //send result to the objects
                for(it=objects.begin();it!=objects.end();++it) {
                    os = it->second;
                    if(os->object->getType()==Object::Controlled)
                        ((ControlledObject*)(os->object))->setJointVelocity(project(m_qdot,os->jointrange));
                }
            }
        } while (locked);

        //Update the Objects
        for(ObjectMap::iterator it=objects.begin();it!=objects.end();++it){
            it->second->object->updateKinematics(ts);
            // mark this object not updated since the constraint will be updated anyway
            // this flag is only useful to detect external updates
            it->second->object->updated(false);
        }
        //Update the Constraints
        for(ConstraintMap::iterator it=constraints.begin();it!=constraints.end();++it){
            ConstraintSet_struct* cs = it->second;
            //Calculate the external pose:
            getConstraintPose(cs->task, cs, external_pose);
            cs->task->modelUpdate(external_pose,ts);
            // update the constraint output and cache
            cs->task->updateKinematics(ts);
        }
        numsubstep--;
    }
    return true;
}

}