body_table.GetCollisionModel().AddBox(size_table_x / 2, size_table_y / 2,
size_table_z / 2) # hemi sizes
body_table.GetCollisionModel().BuildModel()
body_table.SetCollide(True)
# Visualization shape
ChronoPandaInterface.PandaBox(cpi, body_table,
(size_table_x, size_table_y, size_table_z), GRAY)
my_system.Add(body_table)
# Create a constraint that blocks free 3 x y z translations and 3 rx ry rz rotations
# of the table respect to the floor, and impose that the relative imposed position
# depends on a specified motion law.
link_shaker = chrono.ChLinkLockLock()
link_shaker.Initialize(body_table, body_floor, chrono.CSYSNORM)
my_system.Add(link_shaker)
# ..create the function for imposed x horizontal motion, etc.
mfunY = chrono.ChFunction_Sine(0, 1.5, 0.001) # phase, frequency, amplitude
link_shaker.SetMotion_Y(mfunY)
# ..create the function for imposed y vertical motion, etc.
mfunZ = chrono.ChFunction_Sine(0, 1.5, 0.12) # phase, frequency, amplitude
link_shaker.SetMotion_Z(mfunZ)
# Note that you could use other types of ChFunction_ objects, or create
# your custom function by class inheritance (see demo_python.py), or also
# set a function for table rotation , etc.
def run_sim(traits, trial_num, gen_num, difficulty_level):
my_system = chrono.ChSystemNSC()
# Set the default outward/inward shape margins for collision detection
chrono.ChCollisionModel.SetDefaultSuggestedEnvelope(0.001)
chrono.ChCollisionModel.SetDefaultSuggestedMargin(0.001)
# Sets simulation precision
my_system.SetMaxItersSolverSpeed(70)
# Create a contact material (surface property)to share between all objects.
rollfrict_param = 0.5 / 10.0 * 0.05
brick_material = chrono.ChMaterialSurfaceNSC()
brick_material.SetFriction(0.5)
brick_material.SetDampingF(0.2)
brick_material.SetCompliance(0.0000001)
brick_material.SetComplianceT(0.0000001)
brick_material.SetRollingFriction(rollfrict_param)
brick_material.SetSpinningFriction(0.00000001)
brick_material.SetComplianceRolling(0.0000001)
brick_material.SetComplianceSpinning(0.0000001)
# Create the set of bricks in a vertical stack, along Y axis
block_bodies = [] # visualizes bodies
block_shapes = [] # geometry purposes
current_y = 0
for block_index in range(0, 4):
size_brick_x = traits[block_index][0]
size_brick_z = traits[block_index][1]
size_brick_y = traits[block_index][2]
if size_brick_y < settings.MIN_DIMENSIONS_THRESHOLD or size_brick_x < settings.MIN_DIMENSIONS_THRESHOLD or size_brick_z < settings.MIN_DIMENSIONS_THRESHOLD:
return [-50, traits]
mass_brick = settings.BLOCK_MASS
inertia_brick_xx = 1 / 12 * mass_brick * (pow(size_brick_z, 2) + pow(size_brick_y, 2))
inertia_brick_yy = 1 / 12 * mass_brick * (pow(size_brick_x, 2) + pow(size_brick_z, 2))
inertia_brick_zz = 1 / 12 * mass_brick * (pow(size_brick_x, 2) + pow(size_brick_y, 2))
body_brick = chrono.ChBody()
body_brick.SetPos(chrono.ChVectorD(0, current_y + 0.5 * size_brick_y, 0)) # set initial position
current_y += size_brick_y # set tower block positions
# setting mass properties
body_brick.SetMass(mass_brick)
body_brick.SetInertiaXX(chrono.ChVectorD(inertia_brick_xx, inertia_brick_yy, inertia_brick_zz))
# set collision surface properties
body_brick.SetMaterialSurface(brick_material)
# Collision shape
body_brick.GetCollisionModel().ClearModel()
body_brick.GetCollisionModel().AddBox(size_brick_x / 2, size_brick_y / 2,
size_brick_z / 2) # must set half sizes
body_brick.GetCollisionModel().BuildModel()
body_brick.SetCollide(True)
# Visualization shape, for rendering animation
body_brick_shape = chrono.ChBoxShape()
body_brick_shape.GetBoxGeometry().Size = chrono.ChVectorD(size_brick_x / 2, size_brick_y / 2,
size_brick_z / 2)
if block_index % 2 == 0:
body_brick_shape.SetColor(chrono.ChColor(0.65, 0.65, 0.6)) # set gray color only for odd bricks
body_brick.GetAssets().push_back(body_brick_shape)
my_system.Add(body_brick)
block_bodies.append(body_brick)
block_shapes.append(body_brick_shape);
# Create the room floor
body_floor = chrono.ChBody()
body_floor.SetBodyFixed(True)
body_floor.SetPos(chrono.ChVectorD(0, -2, 0))
body_floor.SetMaterialSurface(brick_material)
# Floor's collision shape
body_floor.GetCollisionModel().ClearModel()
body_floor.GetCollisionModel().AddBox(3, 1, 3) # hemi sizes default: 3,1,3
body_floor.GetCollisionModel().BuildModel()
body_floor.SetCollide(True)
# Visualization shape
body_floor_shape = chrono.ChBoxShape()
body_floor_shape.GetBoxGeometry().Size = chrono.ChVectorD(3, 1, 3)
body_floor.GetAssets().push_back(body_floor_shape)
body_floor_texture = chrono.ChTexture()
# body_floor_texture.SetTextureFilename(chrono.GetChronoDataPath() + 'concrete.jpg')
body_floor.GetAssets().push_back(body_floor_texture)
my_system.Add(body_floor)
# Create the shaking table, as a box
size_table_x = 1
size_table_y = 0.2
size_table_z = 1
body_table = chrono.ChBody()
body_table.SetPos(chrono.ChVectorD(0, -size_table_y / 2, 0))
body_table.SetMaterialSurface(brick_material)
# Collision shape
body_table.GetCollisionModel().ClearModel()
body_table.GetCollisionModel().AddBox(size_table_x / 2, size_table_y / 2, size_table_z / 2) # hemi sizes
body_table.GetCollisionModel().BuildModel()
body_table.SetCollide(True)
# Visualization shape
body_table_shape = chrono.ChBoxShape()
body_table_shape.GetBoxGeometry().Size = chrono.ChVectorD(size_table_x / 2, size_table_y / 2, size_table_z / 2)
body_table_shape.SetColor(chrono.ChColor(0.4, 0.4, 0.5))
body_table.GetAssets().push_back(body_table_shape)
body_table_texture = chrono.ChTexture()
# body_table_texture.SetTextureFilename(chrono.GetChronoDataPath() + 'concrete.jpg')
body_table.GetAssets().push_back(body_table_texture)
my_system.Add(body_table)
# Makes the table shake
link_shaker = chrono.ChLinkLockLock()
# link_shaker.SetMotion_X()
link_shaker.Initialize(body_table, body_floor, chrono.CSYSNORM)
my_system.Add(link_shaker)
# ..create the function for imposed y vertical motion, etc.
mfunY = chrono.ChFunction_Sine(0, settings.TABLE_FREQ_Y, settings.TABLE_AMP_Y) # phase, frequency, amplitude
# ..create the function for imposed z horizontal motion, etc.
mfunZ = chrono.ChFunction_Sine(0, settings.TABLE_FREQ_Z, settings.TABLE_AMP_Z) # phase, frequency, amplitude
# ..create the function for imposed x horizontal motion, etc.
mfunX = chrono.ChFunction_Sine(2, 0, 0) # phase, frequency, amplitude
print("Sim env_level " + str(difficulty_level))
if difficulty_level == settings.SHAKE_IN_X_AXIS_LEVEL:
mfunX = chrono.ChFunction_Sine(2, settings.TABLE_FREQ_X, settings.TABLE_AMP_X) # phase, frequency, amplitude
elif difficulty_level >= settings.SHAKE_IN_X_AND_Z_AXIS_LEVEL:
increment = 0.25 * difficulty_level
mfunX = chrono.ChFunction_Sine(2, settings.TABLE_FREQ_X + increment, settings.TABLE_AMP_X) # phase, frequency, amplitude
mfunZ = chrono.ChFunction_Sine(0, settings.TABLE_FREQ_Z + increment, settings.TABLE_AMP_Z) # phase, frequency, amplitude
link_shaker.SetMotion_Y(mfunY)
link_shaker.SetMotion_Z(mfunZ)
link_shaker.SetMotion_X(mfunX)
# ---------------------------------------------------------------------
#
# Create an Irrlicht application to visualize the system
window_name = "Tower Trial: " + str(trial_num) + " Gen: " + str(gen_num)
if trial_num == -1:
window_name = "Initializing Population..."
app = chronoirr.ChIrrApp(my_system, window_name, chronoirr.dimension2du(settings.SCREEN_WIDTH, settings.SCREEN_HEIGHT))
app.AddTypicalSky()
app.AddTypicalLogo(chrono.GetChronoDataPath() + 'logo_pychrono_alpha.png')
app.AddTypicalCamera(chronoirr.vector3df(settings.CAMERA_X, settings.CAMERA_Y, settings.CAMERA_Z))
app.AddLightWithShadow(chronoirr.vector3df(2, 4, 2), # point
chronoirr.vector3df(0, 0, 0), # aimpoint
9, # radius (power)
1, 9, # near, far
30)
# Committing visualization
app.AssetBindAll()
app.AssetUpdateAll();
app.AddShadowAll();
# ---------------------------------------------------------------------
#
# Run the simulation. This is where all of the constraints are set
#
app.SetTimestep(settings.SPEED)
app.SetTryRealtime(True)
app.GetDevice().run()
fitness = 0
brick1_init = block_bodies[0].GetPos().y
brick2_init = block_bodies[1].GetPos().y
brick3_init = block_bodies[2].GetPos().y
brick4_init = block_bodies[3].GetPos().y # Highest
while True:
brick1_curr_height = block_bodies[0].GetPos().y
brick2_curr_height = block_bodies[1].GetPos().y
brick3_curr_height = block_bodies[2].GetPos().y
brick4_curr_height = block_bodies[3].GetPos().y # Highest
# Break conditions
if my_system.GetChTime() > settings.SIMULATION_RUNTIME:
break
if my_system.GetChTime() > settings.SIMULATION_RUNTIME / 2:
mfunX = chrono.ChFunction_Sine(2, 0, 0)
mfunZ = chrono.ChFunction_Sine(2, 0, 0)
link_shaker.SetMotion_Z(mfunZ)
link_shaker.SetMotion_X(mfunX)
# If the blocks fall out of line
if brick1_init - brick1_curr_height > settings.CANCEL_SIM_THRESHOLD or \
brick2_init - brick2_curr_height > settings.CANCEL_SIM_THRESHOLD or \
brick3_init - brick3_curr_height > settings.CANCEL_SIM_THRESHOLD or \
brick4_init - brick4_curr_height > settings.CANCEL_SIM_THRESHOLD:
break
# Record fitness every 1/1000 of the runtime
if 0.01 > my_system.GetChTime() % ((1 / 1000) * settings.SIMULATION_RUNTIME) > 0:
if settings.FITNESS_FUNCTION == settings.Fitness.SumLengths: # Sum of size_y
fitness += block_shapes[0].GetBoxGeometry().GetLengths().y + \
block_shapes[1].GetBoxGeometry().GetLengths().y + \
block_shapes[2].GetBoxGeometry().GetLengths().y + \
block_shapes[3].GetBoxGeometry().GetLengths().y
elif settings.FITNESS_FUNCTION == settings.Fitness.MaxPosition: # Max of y positions
fitness += max(block_bodies[0].GetPos().y,
block_bodies[1].GetPos().y,
block_bodies[2].GetPos().y,
block_bodies[3].GetPos().y)
elif settings.FITNESS_FUNCTION == settings.Fitness.MaxPositionSumLengths: # Max * sum of sizes
fitness += max(block_bodies[0].GetPos().y,
block_bodies[1].GetPos().y,
block_bodies[2].GetPos().y,
block_bodies[3].GetPos().y) * \
block_shapes[0].GetBoxGeometry().GetLengths().y + \
block_shapes[1].GetBoxGeometry().GetLengths().y + \
block_shapes[2].GetBoxGeometry().GetLengths().y + \
block_shapes[3].GetBoxGeometry().GetLengths().y
app.BeginScene()
app.DrawAll()
for substep in range(0, 5):
app.DoStep()
app.EndScene()
app.GetDevice().closeDevice()
print("Fitness: " + str(fitness) + " Gen: " + str(gen_num))
return [fitness, traits]