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------------------------------------------------------------
revno: 3752
committer: Anton Gladky <gladky.anton@xxxxxxxxx>
timestamp: Mon 2013-11-11 17:22:15 +0100
message:
  Add BicyclePedalEngine as a new kinematic motion.
  
  See an example in examples/baraban/BicyclePedalEngine.py
added:
  examples/baraban/BicyclePedalEngine.py
modified:
  pkg/common/KinematicEngines.cpp
  pkg/common/KinematicEngines.hpp


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=== added file 'examples/baraban/BicyclePedalEngine.py'
--- examples/baraban/BicyclePedalEngine.py	1970-01-01 00:00:00 +0000
+++ examples/baraban/BicyclePedalEngine.py	2013-11-11 16:22:15 +0000
@@ -0,0 +1,62 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+import time
+
+## PhysicalParameters 
+Density=2400
+frictionAngle=radians(35)
+tc = 0.001
+en = 0.3
+es = 0.3
+
+## Import wall's geometry
+params=getViscoelasticFromSpheresInteraction(tc,en,es)
+facetMat=O.materials.append(ViscElMat(frictionAngle=frictionAngle,**params)) # **params sets kn, cn, ks, cs
+sphereMat=O.materials.append(ViscElMat(density=Density,frictionAngle=frictionAngle,**params))
+from yade import ymport
+fctIds=O.bodies.append(ymport.stl('baraban.stl',color=(1,0,0),material=facetMat))
+## Spheres
+sphereRadius = 0.2
+nbSpheres = (10,10,10)
+#nbSpheres = (50,50,50)
+for i in xrange(nbSpheres[0]):
+    for j in xrange(nbSpheres[1]):
+        for k in xrange(nbSpheres[2]):
+            x = (i*2 - nbSpheres[0])*sphereRadius*1.1
+            y = (j*2 - nbSpheres[1])*sphereRadius*1.1
+            z = (k*2 - nbSpheres[2])*sphereRadius*1.1
+            s=sphere([x,y,z],sphereRadius,material=sphereMat)
+            O.bodies.append(s)
+
+## Timestep 
+O.dt=.2*tc
+
+## Engines 
+O.engines=[
+	## Resets forces and momenta the act on bodies
+	ForceResetter(),
+	## Using bounding boxes find possible body collisions.
+	InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()]),
+	## Interactions
+	InteractionLoop(
+		## Create geometry information about each potential collision.
+		[Ig2_Sphere_Sphere_ScGeom(), Ig2_Facet_Sphere_ScGeom()],
+		## Create physical information about the interaction.
+		[Ip2_ViscElMat_ViscElMat_ViscElPhys()],
+		## Constitutive law
+		[Law2_ScGeom_ViscElPhys_Basic()],
+	),
+	## Apply gravity
+	## Cundall damping must been disabled!
+	NewtonIntegrator(damping=0,gravity=[0,-9.81,0]),
+## Saving results
+	#VTKRecorder(virtPeriod=0.04,fileName='/tmp/stlimp-',recorders=['spheres','facets']),
+	## Apply kinematics to walls
+	BicyclePedalEngine(ids=fctIds,rotationAxis=[0,0,1],radius = 1.2,angularVelocity=4.0)
+]
+
+from yade import qt
+qt.View()
+#O.saveTmp()
+#O.run()
+

=== modified file 'pkg/common/KinematicEngines.cpp'
--- pkg/common/KinematicEngines.cpp	2013-10-16 13:48:29 +0000
+++ pkg/common/KinematicEngines.cpp	2013-11-11 16:22:15 +0000
@@ -4,7 +4,7 @@
 #include<yade/pkg/dem/Shop.hpp>
 #include<yade/lib/smoothing/LinearInterpolate.hpp>
 
-YADE_PLUGIN((KinematicEngine)(CombinedKinematicEngine)(TranslationEngine)(HarmonicMotionEngine)(RotationEngine)(HelixEngine)(InterpolatingHelixEngine)(HarmonicRotationEngine)(ServoPIDController));
+YADE_PLUGIN((KinematicEngine)(CombinedKinematicEngine)(TranslationEngine)(HarmonicMotionEngine)(RotationEngine)(HelixEngine)(InterpolatingHelixEngine)(HarmonicRotationEngine)(ServoPIDController)(BicyclePedalEngine));
 
 CREATE_LOGGER(KinematicEngine);
 
@@ -109,7 +109,6 @@
 	}
 }
 
-
 void RotationEngine::apply(const vector<Body::id_t>& ids){
 	if (ids.size()>0) {
 		#ifdef YADE_OPENMP
@@ -183,3 +182,33 @@
   TranslationEngine::apply(ids);
 }
 
+
+void BicyclePedalEngine::apply(const vector<Body::id_t>& ids){
+	if (ids.size()>0) {
+		Quaternionr qRotateZVec(Quaternionr().setFromTwoVectors(Vector3r(0,0,1), rotationAxis));
+		
+		Vector3r newPos = Vector3r(cos(fi + angularVelocity*scene->dt)*radius, sin(fi + angularVelocity*scene->dt)*radius, 0.0);
+		Vector3r oldPos = Vector3r(cos(fi)*radius, sin(fi)*radius, 0.0);
+		
+		Vector3r newVel = (oldPos - newPos)/scene->dt;
+		
+		fi += angularVelocity*scene->dt;
+		newVel =  qRotateZVec*newVel;
+		
+		#ifdef YADE_OPENMP
+		const long size=ids.size();
+		#pragma omp parallel for schedule(static)
+		for(long i=0; i<size; i++){
+			const Body::id_t& id=ids[i];
+		#else
+		FOREACH(Body::id_t id,ids){
+		#endif
+			assert(id<(Body::id_t)scene->bodies->size());
+			Body* b=Body::byId(id,scene).get();
+			if(!b) continue;
+			b->state->vel+=newVel;
+		}
+	} else {
+		LOG_WARN("The list of ids is empty! Can't move any body.");
+	}
+}

=== modified file 'pkg/common/KinematicEngines.hpp'
--- pkg/common/KinematicEngines.hpp	2013-07-04 17:36:34 +0000
+++ pkg/common/KinematicEngines.hpp	2013-11-11 16:22:15 +0000
@@ -115,3 +115,15 @@
   DECLARE_LOGGER;
 };
 REGISTER_SERIALIZABLE(ServoPIDController);
+
+struct BicyclePedalEngine: public KinematicEngine{
+	virtual void apply(const vector<Body::id_t>& ids);
+	void postLoad(BicyclePedalEngine&){ rotationAxis.normalize(); }
+	YADE_CLASS_BASE_DOC_ATTRS(BicyclePedalEngine,KinematicEngine,"Engine applying the linear motion of ``bicycle pedal`` e.g. moving points around the axis without rotation",
+		((Real,angularVelocity,0,,"Angular velocity. [rad/s]"))
+		((Vector3r,rotationAxis,Vector3r::UnitX(),Attr::triggerPostLoad,"Axis of rotation (direction); will be normalized automatically."))
+		((Real,radius,-1.0,,"Rotation radius. [m]"))
+		((Real,fi,Mathr::PI/2.0,,"Initial phase [radians]"))
+	);
+};
+REGISTER_SERIALIZABLE(BicyclePedalEngine);