Simbody  3.6
Force.h
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1 #ifndef SimTK_SIMBODY_FORCE_H_
2 #define SimTK_SIMBODY_FORCE_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) 2008-13 Stanford University and the Authors. *
13  * Authors: Peter Eastman, 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"
30 
31 namespace SimTK {
32 
33 class SimbodyMatterSubsystem;
34 class GeneralForceSubsystem;
35 class MobilizedBody;
36 class Force;
37 class ForceImpl;
38 
39 // We only want the template instantiation to occur once. This symbol is defined
40 // in the SimTK core compilation unit that defines the Force class but should
41 // not be defined any other time.
42 #ifndef SimTK_SIMBODY_DEFINING_FORCE
43  extern template class PIMPLHandle<Force, ForceImpl, true>;
44 #endif
45 
51 public:
62  void disable(State&) const;
66  void enable(State&) const;
70  bool isDisabled(const State&) const;
76  void setDisabledByDefault(bool shouldBeDisabled);
80  bool isDisabledByDefault() const;
128  void calcForceContribution(const State& state,
129  Vector_<SpatialVec>& bodyForces,
130  Vector_<Vec3>& particleForces,
131  Vector& mobilityForces) const;
152  Force() {}
156  operator ForceIndex() const {return getForceIndex();}
167  class TwoPointLinearSpring;
168  class TwoPointLinearDamper;
169  class TwoPointConstantForce;
170  class MobilityLinearSpring;
171  class MobilityLinearDamper;
172  class MobilityConstantForce;
173  class MobilityLinearStop;
174  class MobilityDiscreteForce;
175  class DiscreteForces;
176  class LinearBushing;
177  class ConstantForce;
178  class ConstantTorque;
179  class GlobalDamper;
180  class Thermostat;
181  class UniformGravity;
182  class Gravity;
183  class Custom;
184 
185  class TwoPointLinearSpringImpl;
186  class TwoPointLinearDamperImpl;
187  class TwoPointConstantForceImpl;
188  class MobilityLinearSpringImpl;
189  class MobilityLinearDamperImpl;
190  class MobilityConstantForceImpl;
191  class MobilityLinearStopImpl;
192  class MobilityDiscreteForceImpl;
193  class DiscreteForcesImpl;
194  class LinearBushingImpl;
195  class ConstantForceImpl;
196  class ConstantTorqueImpl;
197  class GlobalDamperImpl;
198  class ThermostatImpl;
199  class UniformGravityImpl;
200  class GravityImpl;
201  class CustomImpl;
202 
203 protected:
206  explicit Force(ForceImpl* r) : HandleBase(r) { }
207 };
208 
209 
222 public:
234  TwoPointLinearSpring(GeneralForceSubsystem& forces, const MobilizedBody& body1, const Vec3& station1, const MobilizedBody& body2, const Vec3& station2, Real k, Real x0);
235 
238 
240 };
241 
255 public:
266  TwoPointLinearDamper(GeneralForceSubsystem& forces, const MobilizedBody& body1, const Vec3& station1, const MobilizedBody& body2, const Vec3& station2, Real damping);
267 
270 
272 };
273 
286 public:
297  TwoPointConstantForce(GeneralForceSubsystem& forces, const MobilizedBody& body1, const Vec3& station1, const MobilizedBody& body2, const Vec3& station2, Real force);
298 
301 
303 };
304 
305 
314 public:
315  ConstantForce(GeneralForceSubsystem& forces, const MobilizedBody& body, const Vec3& station, const Vec3& force);
316 
319 
321 };
322 
331 public:
332  ConstantTorque(GeneralForceSubsystem& forces, const MobilizedBody& body, const Vec3& torque);
333 
336 
338 };
339 
355 public:
357 
360 
362 };
363 
375 public:
377  const SimbodyMatterSubsystem& matter,
378  const Vec3& g, Real zeroHeight=0);
379 
382 
383  Vec3 getGravity() const;
384  void setGravity(const Vec3& g);
386  void setZeroHeight(Real height);
388 };
389 
390 } // namespace SimTK
391 
392 #endif // SimTK_SIMBODY_FORCE_H_
Includes internal headers providing declarations for the basic SimTK Core classes,...
Every Simbody header and source file should include this header before any other Simbody header.
#define SimTK_SIMBODY_EXPORT
Definition: Simbody/include/simbody/internal/common.h:68
This type represents the index of a Force element within its subsystem.
A constant force applied to a body station.
Definition: Force.h:313
ConstantForce()
Default constructor creates an empty handle.
Definition: Force.h:318
ConstantForce(GeneralForceSubsystem &forces, const MobilizedBody &body, const Vec3 &station, const Vec3 &force)
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(ConstantForce, ConstantForceImpl, Force)
A constant torque to a body.
Definition: Force.h:330
ConstantTorque()
Default constructor creates an empty handle.
Definition: Force.h:335
ConstantTorque(GeneralForceSubsystem &forces, const MobilizedBody &body, const Vec3 &torque)
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(ConstantTorque, ConstantTorqueImpl, Force)
This class is used to define new force elements.
Definition: Force_Custom.h:193
Arbitrary discrete body forces and mobility (generalized) forces. Useful for applying external forces...
Definition: Force_DiscreteForces.h:41
A general energy "drain" on the system.
Definition: Force.h:354
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(GlobalDamper, GlobalDamperImpl, Force)
GlobalDamper()
Default constructor creates an empty handle.
Definition: Force.h:359
GlobalDamper(GeneralForceSubsystem &forces, const SimbodyMatterSubsystem &matter, Real damping)
This force element represents a uniform gravitational field applied to a set of bodies.
Definition: Force_Gravity.h:70
This force element represents a bushing acting to connect a frame F fixed on one body (B1) to a frame...
Definition: Force_LinearBushing.h:101
A constant generalized force f (a scalar) applied to a mobility.
Definition: Force_MobilityConstantForce.h:45
A discrete mobility (generalized) force f applied to a particular mobility that is specified at const...
Definition: Force_MobilityDiscreteForce.h:52
A linear damper that acts along or around a mobility coordinate to apply a generalized force there.
Definition: Force_MobilityLinearDamper.h:46
A linear spring that acts along or around a mobility coordinate to apply a generalized force there.
Definition: Force_MobilityLinearSpring.h:49
Model a compliant stop element that acts to keep a mobilizer coordinate q within specified bounds.
Definition: Force_MobilityLinearStop.h:65
This is a feedback-controlled force that uses Nose'-Hoover chains to maintain a particular temperatur...
Definition: Force_Thermostat.h:131
A constant force f (a signed scalar) which acts along the line between two points,...
Definition: Force.h:285
TwoPointConstantForce(GeneralForceSubsystem &forces, const MobilizedBody &body1, const Vec3 &station1, const MobilizedBody &body2, const Vec3 &station2, Real force)
Create a TwoPointConstantForce.
TwoPointConstantForce()
Default constructor creates an empty handle.
Definition: Force.h:300
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(TwoPointConstantForce, TwoPointConstantForceImpl, Force)
A force which resists changes in the distance between two points, acting along the line between those...
Definition: Force.h:254
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(TwoPointLinearDamper, TwoPointLinearDamperImpl, Force)
TwoPointLinearDamper()
Default constructor creates an empty handle.
Definition: Force.h:269
TwoPointLinearDamper(GeneralForceSubsystem &forces, const MobilizedBody &body1, const Vec3 &station1, const MobilizedBody &body2, const Vec3 &station2, Real damping)
Create a TwoPointLinearDamper.
A linear spring between two points, specified as a station on each of two bodies.
Definition: Force.h:221
TwoPointLinearSpring(GeneralForceSubsystem &forces, const MobilizedBody &body1, const Vec3 &station1, const MobilizedBody &body2, const Vec3 &station2, Real k, Real x0)
Create a TwoPointLinearSpring.
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(TwoPointLinearSpring, TwoPointLinearSpringImpl, Force)
TwoPointLinearSpring()
Default constructor creates an empty handle.
Definition: Force.h:237
A uniform gravitational force applied to every body in the system. See Force::Gravity for a more flex...
Definition: Force.h:374
UniformGravity(GeneralForceSubsystem &forces, const SimbodyMatterSubsystem &matter, const Vec3 &g, Real zeroHeight=0)
void setGravity(const Vec3 &g)
UniformGravity()
Default constructor creates an empty handle.
Definition: Force.h:381
SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS(UniformGravity, UniformGravityImpl, Force)
void setZeroHeight(Real height)
This is the base class from which all Force element handle classes derive.
Definition: Force.h:50
void disable(State &) const
Disable this force element, effectively removing it from the System for computational purposes (it is...
bool isDisabledByDefault() const
Test whether this force element is disabled by default in which case it must be explicitly enabled be...
Force()
Default constructor for Force handle base class does nothing.
Definition: Force.h:152
const GeneralForceSubsystem & getForceSubsystem() const
Get the GeneralForceSubsystem of which this Force is an element.
ForceIndex getForceIndex() const
Get the index of this force element within its parent force subsystem.
void calcForceContribution(const State &state, Vector_< SpatialVec > &bodyForces, Vector_< Vec3 > &particleForces, Vector &mobilityForces) const
Calculate the force that would be applied by this force element if the given state were realized to D...
void enable(State &) const
Enable this force element if it was previously disabled.
void setDisabledByDefault(bool shouldBeDisabled)
Normally force elements are enabled when defined and can be disabled later.
bool isDisabled(const State &) const
Test whether this force element is currently disabled in the supplied State.
Real calcPotentialEnergyContribution(const State &state) const
Calculate the potential energy contribution that is made by this force element at the given state.
Force(ForceImpl *r)
Use this in a derived Force handle class constructor to supply the concrete implementation object to ...
Definition: Force.h:206
This is a concrete subsystem which can apply arbitrary forces to a MultibodySystem.
Definition: GeneralForceSubsystem.h:47
A MobilizedBody is Simbody's fundamental body-and-joint object used to parameterize a system's motion...
Definition: MobilizedBody.h:169
This subsystem contains the bodies ("matter") in the multibody system, the mobilizers (joints) that d...
Definition: SimbodyMatterSubsystem.h:133
This object is intended to contain all state information for a SimTK::System, except topological info...
Definition: State.h:280
This is the vector class intended to appear in user code for large, variable size column vectors.
Definition: Vector_.h:50
This is the top-level SimTK namespace into which all SimTK names are placed to avoid collision with o...
Definition: Assembler.h:37
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