Simbody  3.7
CableSpring.h
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1 #ifndef SimTK_SIMBODY_CABLE_SPRING_H_
2 #define SimTK_SIMBODY_CABLE_SPRING_H_
3 
4 /* -------------------------------------------------------------------------- *
5  * Simbody(tm) *
6  * -------------------------------------------------------------------------- *
7  * This is part of the SimTK biosimulation toolkit originating from *
8  * Simbios, the NIH National Center for Physics-Based Simulation of *
9  * Biological Structures at Stanford, funded under the NIH Roadmap for *
10  * Medical Research, grant U54 GM072970. See https://simtk.org/home/simbody. *
11  * *
12  * Portions copyright (c) 2012-13 Stanford University and the Authors. *
13  * Authors: Michael Sherman *
14  * Contributors: *
15  * *
16  * Licensed under the Apache License, Version 2.0 (the "License"); you may *
17  * not use this file except in compliance with the License. You may obtain a *
18  * copy of the License at http://www.apache.org/licenses/LICENSE-2.0. *
19  * *
20  * Unless required by applicable law or agreed to in writing, software *
21  * distributed under the License is distributed on an "AS IS" BASIS, *
22  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
23  * See the License for the specific language governing permissions and *
24  * limitations under the License. *
25  * -------------------------------------------------------------------------- */
26 
27 #include "SimTKcommon.h"
29 #include "simbody/internal/Force.h"
31 
37 namespace SimTK {
38 
91 public:
92 
116  const CablePath& path,
117  Real defaultStiffness,
118  Real defaultSlackLength,
119  Real defaultDissipationCoef);
120 
123 
124 
125 //------------------------------------------------------------------------------
159 
174 //------------------------------------------------------------------------------
200  Real stiffness) const;
209  Real slackLength) const;
218  Real dissipationCoef) const;
219 
225 Real getStiffness(const State& state) const;
231 Real getSlackLength(const State& state) const;
239 Real getDissipationCoef(const State& state) const;
244 //------------------------------------------------------------------------------
262 Real getLength(const State& state) const;
267 //------------------------------------------------------------------------------
286 Real getLengthDot(const State& state) const;
287 
292 //------------------------------------------------------------------------------
311 Real getTension(const State& state) const;
316 //------------------------------------------------------------------------------
330 Real getPotentialEnergy(const State& state) const;
331 
342 Real getPowerDissipation(const State& state) const;
343 
356 Real getDissipatedEnergy(const State& state) const;
357 
370 void setDissipatedEnergy(State& state, Real energy) const;
379 const CablePath& getCablePath() const; // Don't show this in Doxygen.
383 class Impl;
385  (CableSpring, CableSpring::Impl, Force);
387 };
388 
389 } // namespace SimTK
390 
391 #endif // SimTK_SIMBODY_CABLE_SPRING_H_
SimTK::State
This object is intended to contain all state information for a SimTK::System, except topological info...
Definition: State.h:280
SimTK::CableSpring::setDissipatedEnergy
void setDissipatedEnergy(State &state, Real energy) const
Set the accumulated dissipated energy to an arbitrary value.
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS
#define SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(DERIVED, DERIVED_IMPL, PARENT)
Definition: PrivateImplementation.h:343
SimTK::CableSpring::setDissipationCoef
const CableSpring & setDissipationCoef(State &state, Real dissipationCoef) const
Set the dissipation coefficient c that will be used for this cable spring when evaluated using this S...
SimTK::CableSpring::setSlackLength
const CableSpring & setSlackLength(State &state, Real slackLength) const
Set the slack length L0 that will be used for this cable spring when evaluated using this State.
SimTK::CableSpring::getLengthDot
Real getLengthDot(const State &state) const
Return the current rate of length change (time derivative of length) of the CablePath that underlies ...
SimTK::CableSpring::setDefaultDissipationCoef
CableSpring & setDefaultDissipationCoef(Real dissipation)
Set the dissipation coefficient c that will be used by default for this cable spring; must be nonnega...
SimTK::CableSpring::getCablePath
const CablePath & getCablePath() const
Get a reference to the CablePath that is used to determine the routing of this cable spring force ele...
SimTK
This is a System that represents the dynamics of a particle moving along a smooth surface.
Definition: Assembler.h:37
SimTK::CableSpring::getPotentialEnergy
Real getPotentialEnergy(const State &state) const
Obtain the potential energy stored in this cable spring in the current configuration.
CablePath.h
SimTKcommon.h
SimTK::CableSpring::getPowerDissipation
Real getPowerDissipation(const State &state) const
Obtain the rate at which energy is being dissipated by this cable spring, that is,...
SimTK::Force
This is the base class from which all Force element handle classes derive.
Definition: Force.h:50
SimTK::GeneralForceSubsystem
This is a concrete subsystem which can apply arbitrary forces to a MultibodySystem.
Definition: GeneralForceSubsystem.h:47
SimTK::CableSpring::getTension
Real getTension(const State &state) const
Return the current level of tension in the cable spring.
SimTK::CableSpring
This force element implements a passive elastic element (like a rubber band) that follows a frictionl...
Definition: CableSpring.h:90
SimTK::CableSpring::getStiffness
Real getStiffness(const State &state) const
Return the stiffness (spring constant) k currently being used for this cable spring by this State.
SimTK::CableSpring::setDefaultSlackLength
CableSpring & setDefaultSlackLength(Real slackLength)
Set the slack length L0 that will be used by default for this cable spring; must be nonnegative.
SimTK::CableSpring::CableSpring
CableSpring(GeneralForceSubsystem &forces, const CablePath &path, Real defaultStiffness, Real defaultSlackLength, Real defaultDissipationCoef)
Create an elastic force element that follows a given CablePath and add it to a GeneralForceSubsystem.
SimTK::CableSpring::getDefaultSlackLength
Real getDefaultSlackLength() const
Return the slack length L0 that will be used by default for this cable spring.
SimTK::CableSpring::CableSpring
CableSpring()
Default constructor creates an empty handle.
Definition: CableSpring.h:122
SimTK::CableSpring::getDefaultDissipationCoef
Real getDefaultDissipationCoef() const
Return the dissipation coefficient c that will be used by default for this cable spring.
SimTK::CableSpring::getSlackLength
Real getSlackLength(const State &state) const
Return the slack length L0 currently being used for this cable spring by this State.
SimTK_SIMBODY_EXPORT
#define SimTK_SIMBODY_EXPORT
Definition: Simbody/include/simbody/internal/common.h:68
SimTK::CablePath
This class represents the path of a frictionless cable from an origin point fixed to a body,...
Definition: CablePath.h:92
SimTK::CableSpring::setStiffness
const CableSpring & setStiffness(State &state, Real stiffness) const
Set the stiffness (spring constant) k that will be used for this cable spring when evaluated using th...
SimTK::Real
SimTK_Real Real
This is the default compiled-in floating point type for SimTK, either float or double.
Definition: SimTKcommon/include/SimTKcommon/internal/common.h:606
SimTK::CableSpring::getDefaultStiffness
Real getDefaultStiffness() const
Return the stiffnesses k that will be used by default for this cable spring.
SimTK::CableSpring::getDissipationCoef
Real getDissipationCoef(const State &state) const
Return the dissipation coefficient c currently being used for this cable spring by this State.
Force.h
SimTK::CableSpring::getDissipatedEnergy
Real getDissipatedEnergy(const State &state) const
Obtain the total amount of energy dissipated by this cable spring since some arbitrary starting point...
SimTK::CableSpring::getLength
Real getLength(const State &state) const
Return the current length of the CablePath that underlies this cable spring element.
common.h
SimTK::CableSpring::setDefaultStiffness
CableSpring & setDefaultStiffness(Real stiffness)
Set the stiffness (spring constant) k that will be used by default for this cable spring; must be non...