friction.h

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/* $Header: /var/cvs/mbdyn/mbdyn/mbdyn-1.0/mbdyn/struct/friction.h,v 1.36 2017/01/12 14:46:43 masarati Exp $ */
/* 
 * MBDyn (C) is a multibody analysis code. 
 * http://www.mbdyn.org
 *
 * Copyright (C) 2003-2017
 *
 * Marco Morandini      <morandini@aero.polimi.it>
 *
 * Dipartimento di Ingegneria Aerospaziale - Politecnico di Milano
 * via La Masa, 34 - 20156 Milano, Italy
 * http://www.aero.polimi.it
 *
 * Changing this copyright notice is forbidden.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation (version 2 of the License).
 * 
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/* Copyright (C) 2003 Marco Morandini*/

#ifndef FRICTION_H
#define FRICTION_H

#include "ScalarFunctions.h"
#include "simentity.h"
#include "elem.h"
#include "JacSubMatrix.h"

class BasicFriction : public SimulationEntity{
private:
        void SetValue(DataManager *pDM,
                        VectorHandler& X, VectorHandler& XP,
                        SimulationEntity::Hints *ph = 0) { NO_OP; };
public:
/*
 *      unsigned int iGetNumDof(void) const;
 *      DofOrder::Order GetDofType(unsigned int i) const;
 *      DofOrder::Order GetEqType (unsigned int i) const;
 *      void SetValue(VectorHandler&X, VectorHandler&XP);
 *      void BeforePredict(VectorHandler&,
 *              VectorHandler&,
 *              VectorHandler&,
 *              VectorHandler&) const;
 *      void AfterPredict(VectorHandler&X, VectorHandler&XP);
 *      void Update(const VectorHandler&XCurr, const VectorHandler&XPrimeCurr);
 *      void AfterConvergence(VectorHandler&X, VectorHandler&XP);
 */
        virtual void SetValue(DataManager *pDM,
                        VectorHandler&X, VectorHandler&XP,
                        SimulationEntity::Hints *ph = 0,
                        const unsigned int solution_startdof = 0);
        virtual doublereal fc(void) const = 0;
        virtual void AssRes(
                SubVectorHandler& WorkVec,
                const unsigned int startdof,
                const unsigned int solution_startdof,
                const doublereal F,
                const doublereal v,
                const VectorHandler& X,
                const VectorHandler& XP) 
                        throw(Elem::ChangedEquationStructure) = 0;
        virtual void AssJac(
                FullSubMatrixHandler& WorkMat,
                ExpandableRowVector& dfc,
                const unsigned int startdof,
                const unsigned int solution_startdof,
                const doublereal dCoef,
                const doublereal F,
                const doublereal v,
                const VectorHandler& X,
                const VectorHandler& XP,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const = 0;
        virtual void AfterConvergence(
                const doublereal F,
                const doublereal v,
                const VectorHandler&X, 
                const VectorHandler&XP,
                const unsigned int solution_startdof) {};
};

class BasicShapeCoefficient {
public:
        virtual ~BasicShapeCoefficient(void){};
        virtual doublereal Sh_c(void) const = 0;
        virtual doublereal Sh_c(
                const doublereal f,
                const doublereal F,
                const doublereal v) = 0;
        virtual void dSh_c(
                ExpandableRowVector& dShc,
                const doublereal f,
                const doublereal F,
                const doublereal v,
                const ExpandableRowVector& dfc,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const = 0;
};

class ModLugreFriction : public BasicFriction {
private:
        const doublereal sigma0;
        const doublereal sigma1;
        const doublereal sigma2;
        const doublereal kappa;
        const DifferentiableScalarFunction & fss;
        doublereal f;
        doublereal alpha(const doublereal z,
                const doublereal v) const;
        doublereal alphad_v(const doublereal z,
                const doublereal v) const;
        doublereal alphad_z(const doublereal z,
                const doublereal v) const;
        const doublereal fs(const doublereal&v) const;
        const doublereal fsd(const doublereal&v) const;
public:
        ModLugreFriction(
                const doublereal sigma0,
                const doublereal sigma1,
                const doublereal sigma2,
                const doublereal kappa,
                const BasicScalarFunction *const ff);
        void SetValue(DataManager *pDM,
                        VectorHandler&X, VectorHandler&XP, 
                        SimulationEntity::Hints *ph = 0,
                        const unsigned int solution_startdof = 0);
        unsigned int iGetNumDof(void) const;
        virtual std::ostream&
        DescribeDof(std::ostream& out,
                const char *prefix = "",
                bool bInitial = false) const;
        virtual void
        DescribeDof(std::vector<std::string>& desc,
                bool bInitial = false,
                int i = -1) const;
        virtual std::ostream&
        DescribeEq(std::ostream& out,
                const char *prefix = "",
                bool bInitial = false) const;
        virtual void
        DescribeEq(std::vector<std::string>& desc,
                bool bInitial = false,
                int i = -1) const;
        DofOrder::Order GetDofType(unsigned int i) const;
        DofOrder::Order GetEqType (unsigned int i) const;
        doublereal fc(void) const;
        void AssRes(
                SubVectorHandler& WorkVec,
                const unsigned int startdof,
                const unsigned int solution_startdof,
                const doublereal F,
                const doublereal v,
                const VectorHandler& X,
                const VectorHandler& XP) throw(Elem::ChangedEquationStructure);
        void AssJac(
                FullSubMatrixHandler& WorkMat,
                ExpandableRowVector& dfc,
                const unsigned int startdof,
                const unsigned int solution_startdof,
                const doublereal dCoef,
                const doublereal F,
                const doublereal v,
                const VectorHandler& X,
                const VectorHandler& XP,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const;
};

class DiscreteCoulombFriction : public BasicFriction {
private:
        enum tr_type{
                null,
                from_sticked_to_sliding,
                from_sticking_to_sliding,
                from_sliding_to_sticked,
                from_sliding_to_sticking};
        enum status_type{
                sticked,
                sticking,
                sliding};
        logical converged_sticked;
        status_type status;
        tr_type transition_type;        
        doublereal converged_v;
        logical first_iter;
        logical first_switch;
        doublereal previous_switch_v;
        doublereal current_velocity;
        doublereal saved_sliding_velocity;
        doublereal saved_sliding_friction;
        doublereal sigma2;
        doublereal vel_ratio;
        doublereal current_friction_force;
        
        const DifferentiableScalarFunction & fss;
        doublereal f;
public:
        DiscreteCoulombFriction(
                const BasicScalarFunction *const ff,
                const doublereal s2,
                const doublereal vr);
        void SetValue(DataManager *pDM,
                        VectorHandler&X, VectorHandler&XP, 
                        SimulationEntity::Hints *ph = 0,
                        const unsigned int solution_startdof = 0);
        unsigned int iGetNumDof(void) const;
        virtual std::ostream&
        DescribeDof(std::ostream& out,
                const char *prefix = "",
                bool bInitial = false) const;
        virtual void
        DescribeDof(std::vector<std::string>& desc,
                bool bInitial = false,
                int i = -1) const;
        virtual std::ostream&
        DescribeEq(std::ostream& out,
                const char *prefix = "",
                bool bInitial = false) const;
        virtual void
        DescribeEq(std::vector<std::string>& desc,
                bool bInitial = false,
                int i = -1) const;
        DofOrder::Order GetDofType(unsigned int i) const;
        DofOrder::Order GetEqType (unsigned int i) const;
        doublereal fc(void) const;
        void AfterConvergence(
                const doublereal F,
                const doublereal v,
                const VectorHandler&X, 
                const VectorHandler&XP,
                const unsigned int solution_startdof);
        void AssRes(
                SubVectorHandler& WorkVec,
                const unsigned int startdof,
                const unsigned int solution_startdof,
                const doublereal F,
                const doublereal v,
                const VectorHandler& X,
                const VectorHandler& XP) throw(Elem::ChangedEquationStructure);
        void AssJac(
                FullSubMatrixHandler& WorkMat,
                ExpandableRowVector& dfc,
                const unsigned int startdof,
                const unsigned int solution_startdof,
                const doublereal dCoef,
                const doublereal F,
                const doublereal v,
                const VectorHandler& X,
                const VectorHandler& XP,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const;
};


class SimpleShapeCoefficient : public BasicShapeCoefficient {
public:
        virtual doublereal Sh_c(void) const;
        virtual doublereal Sh_c(
                const doublereal f,
                const doublereal F,
                const doublereal v);
        virtual void dSh_c(
                ExpandableRowVector& dShc,
                const doublereal f,
                const doublereal F,
                const doublereal v,
                const ExpandableRowVector& dfc,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const;
};



class SimplePlaneHingeJointSh_c : public BasicShapeCoefficient {
private:
        doublereal shc;
public:
        SimplePlaneHingeJointSh_c(void);
        virtual doublereal Sh_c(void) const;
        doublereal Sh_c(
                const doublereal f,
                const doublereal F,
                const doublereal v);
        void dSh_c(
                ExpandableRowVector& dShc,
                const doublereal f,
                const doublereal F,
                const doublereal v,
                const ExpandableRowVector& dfc,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const;
};

class ScrewJointSh_c : public BasicShapeCoefficient {
private:
        doublereal shc;
        
        const doublereal radius;
        const doublereal half_thread_angle;
        const doublereal pitch_angle;
        const doublereal sec_half_thread_angle;
        const doublereal tg_pitch;
        const doublereal tg_pitch2;
public:
        ScrewJointSh_c(
                const doublereal r,
                const doublereal hta
        ): 
                radius(r), 
                half_thread_angle(hta), 
                pitch_angle(0.),
                sec_half_thread_angle(1. / std::cos(half_thread_angle)),
                tg_pitch(0.),
                tg_pitch2(0.) {
        };
        doublereal ComputePitchAngle(const doublereal pitch) {
                const_cast<doublereal&>(tg_pitch) = pitch / (2. * M_PI * radius);
                const_cast<doublereal&>(tg_pitch2) = tg_pitch * tg_pitch;
                const_cast<doublereal&>(pitch_angle) = std::atan(tg_pitch);
                const_cast<doublereal&>(half_thread_angle) = std::atan(
                        std::cos(pitch_angle) * std::tan(half_thread_angle)
                );
                return radius / std::cos(pitch_angle);
        };
        virtual doublereal Sh_c(void) const {return shc;};
        doublereal Sh_c(
                const doublereal f,
                const doublereal F,
                const doublereal v) {
                
                shc  = radius * (f * sec_half_thread_angle * (1 + tg_pitch2)) /
                        (f * sec_half_thread_angle * tg_pitch - 1.);
                return shc;
        };
        void dSh_c(
                ExpandableRowVector& dShc,
                const doublereal f,
                const doublereal F,
                const doublereal v,
                const ExpandableRowVector& dfc,
                const ExpandableRowVector& dF,
                const ExpandableRowVector& dv) const {
                doublereal dsh_fc = radius * (-sec_half_thread_angle * (1 + tg_pitch2) ) /
                        std::pow(f * sec_half_thread_angle * tg_pitch - 1., 2.);
                dShc.ReDim(1);
                dShc.Set(dsh_fc, 1);
                dShc.Link(1, &dfc);
        };
};

//---------------------------------------

BasicFriction *const ParseFriction(MBDynParser& HP,
        DataManager * pDM);

BasicShapeCoefficient *const ParseShapeCoefficient(MBDynParser& HP);

#endif /* FRICTION_H */