mouseInteractionExample.py
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1#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2# This is an EXUDYN example
3#
4# Details: This is the first interactive mouse motion example;
5# use your mouse to drag the end of the chain;
6# models a chain of 3D rigid bodies connected with revolute joints;
7# may require RESTART of python kernel to work properly!
8#
9# Author: Johannes Gerstmayr
10# Date: 2020-12-06
11#
12# Copyright:This file is part of Exudyn. Exudyn is free software. You can redistribute it and/or modify it under the terms of the Exudyn license. See 'LICENSE.txt' for more details.
13#
14#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
15
16import exudyn as exu
17from exudyn.itemInterface import *
18from exudyn.utilities import * #includes itemInterface and rigidBodyUtilities
19import exudyn.graphics as graphics #only import if it does not conflict
20from exudyn.graphicsDataUtilities import *
21
22from math import sin, cos, pi
23
24SC = exu.SystemContainer()
25mbs = SC.AddSystem()
26
27activateWithKeyPress = True #activate mouse drag with keypress 'D'
28
29color = [0.1,0.1,0.8,1]
30
31sx = 0.25
32sy = 0.1
33sz = 0.1
34
35nBodies = 16
36
37Ltot = nBodies*sx
38sc = 4 #size of coordinate system
39coordSys0 = graphics.Cylinder([0,0,0], [sz,0,0], 0.01, color=graphics.color.red)
40coordSys1 = graphics.Cylinder([0,0,0], [0,sz,0], 0.01, color=graphics.color.green)
41coordSys2 = graphics.Cylinder([0,0,0], [0,0,sz], 0.01, color=graphics.color.blue)
42oGround=mbs.AddObject(ObjectGround(referencePosition= [0,0,0],
43 visualization=VObjectGround(graphicsData= [coordSys0, coordSys1, coordSys2])))
44
45m=1 #mass
46density = 2000
47
48nodeList=[]
49objectList=[]
50
51nRB=-1
52com=[0,0,0]
53
54RBinertia = InertiaCuboid(density=density, sideLengths=[sx,sy,sz])
55
56mPosGround = mbs.AddMarker(MarkerBodyRigid(bodyNumber = oGround,
57 localPosition=[0,0,0]))
58mPosLast = mPosGround
59
60deltaAngleZ = 0.05*pi/nBodies
61p0 = np.array([0,0,0])
62
63#create a chain of bodies:
64for i in range(nBodies):
65
66 A = RotationMatrixZ(i*deltaAngleZ)
67 deltaRot2 = RotationMatrixZ(0.5*deltaAngleZ)
68 p0 = p0 + A@[0.5*sx,0,0]
69
70 omega0 = [0,0,0] #arbitrary initial angular velocity
71 v0 = [0.,0.,0.] #initial translational velocity
72
73 color=[1,0.1,0.1,1]
74
75 oGraphics = graphics.BrickXYZ(-sx*0.5,-sy*0.5,-sz*0.5, sx*0.5, sy*0.5, sz*0.5, color)
76
77 dictRB = mbs.CreateRigidBody(
78 inertia=RBinertia,
79 referencePosition=p0,
80 referenceRotationMatrix=A,
81 initialVelocity=v0,
82 initialAngularVelocity=omega0,
83 gravity=[0., 0., -9.81],
84 graphicsDataList=[oGraphics],
85 returnDict=True)
86 [nRB, oRB] = [dictRB['nodeNumber'], dictRB['bodyNumber']]
87
88 nodeList += [nRB]
89 objectList += [oRB]
90 mPos = mbs.AddMarker(MarkerBodyRigid(bodyNumber = oRB, localPosition = [-0.5*sx,0,0]))
91 lastDeltaRot2 = deltaRot2
92 if i == 0:
93 lastDeltaRot2 = RotationMatrixZ(0)
94
95 mbs.AddObject(GenericJoint(markerNumbers = [mPos, mPosLast],
96 constrainedAxes=[1,1,1, 1,0,1],
97 rotationMarker0=lastDeltaRot2.T,
98 rotationMarker1=lastDeltaRot2,
99 visualization=VGenericJoint(axesRadius = 0.5*sy, axesLength=1.1*sz)))
100
101 #marker for next chain body
102 mPosLast = mbs.AddMarker(MarkerBodyRigid(bodyNumber = oRB, localPosition = [0.5*sx,0,0]))
103
104 #add damping to bodies:
105 mbs.AddObject(ObjectConnectorCartesianSpringDamper(markerNumbers = [mPosGround, mPosLast],
106 damping = [40]*3,
107 visualization=VCartesianSpringDamper(show=False)))
108
109 p0 = p0 + A@[0.5*sx,0,0]
110
111#activate by keypress 'D':
112mbs.variables['activateMouseDrag'] = True
113if activateWithKeyPress:
114 mbs.variables['activateMouseDrag'] = False
115
116def UFmouseDrag0(mbs, t, itemIndex, u, v, k, d, offset): #changed 2023-01-21:, mu, muPropZone):
117 if not mbs.variables['activateMouseDrag'] == True:
118 return 0
119 p = SC.GetCurrentMouseCoordinates(True)
120 p = SC.GetRenderState()['openGLcoordinates']
121 #print("u=",u)
122 return k*(Ltot-0.5*sx+u-p[0]) + d*v
123
124def UFmouseDrag1(mbs, t, itemIndex, u, v, k, d, offset): #changed 2023-01-21:, mu, muPropZone):
125 if not mbs.variables['activateMouseDrag'] == True:
126 return 0
127 p = SC.GetCurrentMouseCoordinates(True)
128 return k*(u-p[1]) + d*v
129
130def UFmouseDrag2(mbs, t, itemIndex, u, v, k, d, offset): #changed 2023-01-21:, mu, muPropZone):
131 if not mbs.variables['activateMouseDrag'] == True:
132 return 0
133 p = SC.GetCurrentMouseCoordinates(True)
134 return k*(u-p[1]) + d*v
135
136if True:
137 nGround = mbs.AddNode(NodePointGround())
138 mGroundCoordinate = mbs.AddMarker(MarkerNodeCoordinate(nodeNumber=nGround, coordinate = 0))
139 k=5.*1e4
140 mCoord0 = mbs.AddMarker(MarkerNodeCoordinate(nodeNumber=nodeList[-1], coordinate = 0))
141 mCoord1 = mbs.AddMarker(MarkerNodeCoordinate(nodeNumber=nodeList[-1], coordinate = 1))
142 mCoord2 = mbs.AddMarker(MarkerNodeCoordinate(nodeNumber=nodeList[-1], coordinate = 2))
143
144 mbs.AddObject(CoordinateSpringDamper(markerNumbers=[mGroundCoordinate, mCoord0],
145 stiffness=k, damping=0.01*k,
146 springForceUserFunction=UFmouseDrag0,
147 visualization=VCoordinateSpringDamper(show=False),
148 ))
149 mbs.AddObject(CoordinateSpringDamper(markerNumbers=[mGroundCoordinate, mCoord2],
150 stiffness=k, damping=0.01*k,
151 springForceUserFunction=UFmouseDrag2,
152 visualization=VCoordinateSpringDamper(show=False),
153 ))
154
155mbs.Assemble()
156#exu.Print(mbs)
157
158simulationSettings = exu.SimulationSettings() #takes currently set values or default values
159
160tEnd = 10000
161h = 0.001
162simulationSettings.timeIntegration.numberOfSteps = int(tEnd/h)
163simulationSettings.timeIntegration.endTime = tEnd
164simulationSettings.solutionSettings.writeSolutionToFile = False
165simulationSettings.solutionSettings.solutionWritePeriod = simulationSettings.timeIntegration.endTime/1000
166simulationSettings.timeIntegration.verboseMode = 1
167
168#good for interactive examples, as it is independent of CPU power ...
169simulationSettings.timeIntegration.simulateInRealtime = True
170simulationSettings.linearSolverType = exu.LinearSolverType.EigenSparse
171
172simulationSettings.timeIntegration.newton.absoluteTolerance = 1e2 #if no force acts
173simulationSettings.timeIntegration.newton.useModifiedNewton = True
174simulationSettings.timeIntegration.generalizedAlpha.spectralRadius = 0.5 #0.6 works well
175
176simulationSettings.solutionSettings.solutionInformation = "mouse interaction example: press 'D' to (de-)activate mouse drag, F2 to switch key functionality"
177
178#+++++++++++++++++++++++++++++++++++
179#these options are not necessary:
180SC.visualizationSettings.nodes.defaultSize = 0.025
181SC.visualizationSettings.nodes.drawNodesAsPoint = False
182SC.visualizationSettings.nodes.showBasis = False
183
184SC.visualizationSettings.openGL.light0position = [0.2,0.2,10,0]
185
186SC.visualizationSettings.openGL.light1position = [1,1,-10,0]
187SC.visualizationSettings.openGL.light1ambient= 0. #0.25
188SC.visualizationSettings.openGL.light1diffuse= 0.5 #0.4
189SC.visualizationSettings.openGL.light1specular= 0.6 #0.4
190SC.visualizationSettings.openGL.enableLight1 = True
191
192SC.visualizationSettings.openGL.lightModelTwoSide= True
193
194SC.visualizationSettings.general.drawWorldBasis= True
195SC.visualizationSettings.general.graphicsUpdateInterval = 0.01
196
197SC.visualizationSettings.openGL.multiSampling = 4
198SC.visualizationSettings.openGL.lineWidth = 2
199SC.visualizationSettings.window.ignoreKeys = True #otherwise keyPressUserFunction not called!
200SC.visualizationSettings.general.useMultiThreadedRendering = True
201
202useGraphics = True
203if useGraphics:
204 exu.StartRenderer()
205 if 'renderState' in exu.sys:
206 SC.SetRenderState(exu.sys['renderState'])
207 else:
208 renderState = {'centerPoint': [-0.33064934611320496,
209 -0.5762133598327637,
210 0.41875001788139343],
211 'maxSceneSize': 1.75,
212 'zoom': 4.042552471160889,
213 'currentWindowSize': [1024, 768],
214 'modelRotation': [[1.0, 0.0, 0.0],
215 [0.0, -4.371138828673793e-08, -1.0],
216 [0.0, 1.0, -4.371138828673793e-08]],
217 'mouseCoordinates': [713.0, 379.0],
218 'openGLcoordinates': [1.7853742130100727, -0.5235759578645229]}
219 SC.SetRenderState(renderState)
220 SC.SetRenderState(renderState)
221 mbs.WaitForUserToContinue()
222
223#+++++++++++++++++++++++++++++++++++
224#react on key press, in development state:
225#causes crash at termination of python code ...
226def UFkeyPress(key, action, mods):
227 #print('key:',key)
228 if chr(key) == 'D' and action == 1: #use capital letters for comparison!!! action 1 == press
229 mbs.variables['activateMouseDrag'] = not mbs.variables['activateMouseDrag']
230
231if activateWithKeyPress:
232 SC.visualizationSettings.window.keyPressUserFunction = UFkeyPress
233
234
235mbs.SolveDynamic(simulationSettings)
236SC.visualizationSettings.window.ResetKeyPressUserFunction()
237
238if useGraphics:
239 exu.StopRenderer() #safely close rendering window!