# Amira Abdel-Rahman # (c) Massachusetts Institute of Technology 2020 ######################### 1. Voxel Design ########################### setup = Dict() ### 1.b Draw Lattice rhino=false voxelSize=0.001 latticeSizeX=7 latticeSizeY=2 latticeSizeZ=2 gridSize=10 setup["gridSize"]=gridSize setup["rhino"]=false setup["useVoxelList"]=false setup["latticeSizeX"]=latticeSizeX setup["latticeSizeY"]=latticeSizeY setup["latticeSizeZ"]=latticeSizeZ ######################### 2. Boundary Conditions ######################### ######################### 2.a. Global Settings ######################### #scaling params setup["voxelSize"]=voxelSize; #voxel size setup["scale"]=1e4; #scale for visualization setup["hierarchical"]=true; #hierachical simualtion #simulation params setup["numTimeSteps"]=5000; #num of saved timesteps for simulation setup["poisson"]=false; # account for poisson ration (only for hierarchical) setup["linear"]=true; # linear vs non-linear setup["thermal"]=true; #if there is change in temperature setup["globalDamping"]=0.15; # (usually from 0.1 to 0.4) #visualization params setup["maxNumFiles"]=200; #num of saved timesteps for visualization ######################### 2.b. Materials ######################### #default material material1= Dict() material1["area"]=voxelSize*voxelSize material1["density"]=1e3 material1["stiffness"]=1e6 material1["poissonRatio"]=0.0 material1["cTE"]=0.0 #coefficient of thermal expansion #large bounding box for default material boundingBoxMaterial1=Dict() boundingBoxMaterial1["min"]=Dict() boundingBoxMaterial1["max"]=Dict() boundingBoxMaterial1["min"]["x"]=-voxelSize*gridSize; boundingBoxMaterial1["min"]["y"]=-voxelSize*gridSize; boundingBoxMaterial1["min"]["z"]=-voxelSize*gridSize; boundingBoxMaterial1["max"]["x"]= voxelSize*gridSize; boundingBoxMaterial1["max"]["y"]= voxelSize*gridSize; boundingBoxMaterial1["max"]["z"]= voxelSize*gridSize; #second material material2= Dict() material2["area"]=voxelSize*voxelSize material2["density"]=1e3 material2["stiffness"]=1e6 material2["poissonRatio"]=0.0 material2["cTE"]=0.1 #coefficient of thermal expansion #bounding box material 2 boundingBoxMaterial2=Dict() boundingBoxMaterial2["min"]=Dict() boundingBoxMaterial2["max"]=Dict() boundingBoxMaterial2["min"]["x"]=0; boundingBoxMaterial2["min"]["y"]=voxelSize; boundingBoxMaterial2["min"]["z"]=0; boundingBoxMaterial2["max"]["x"]= voxelSize*(latticeSizeX); boundingBoxMaterial2["max"]["y"]= voxelSize*(latticeSizeY); boundingBoxMaterial2["max"]["z"]= voxelSize*(latticeSizeZ); setup["materials"]=[ [boundingBoxMaterial1,material1], [boundingBoxMaterial2,material2] ]; ######################### 2.c. Supports ######################### #x,y,z,rx,ry,rz (default is pinned joing i.e [false,false,false,true,true,true]) dof=[true,true,true,true,true,true] boundingBoxSupport1=Dict() boundingBoxSupport1["min"]=Dict() boundingBoxSupport1["max"]=Dict() boundingBoxSupport1["min"]["x"]= 0; boundingBoxSupport1["min"]["y"]= 0; boundingBoxSupport1["min"]["z"]= 0; boundingBoxSupport1["max"]["x"]= voxelSize; boundingBoxSupport1["max"]["y"]= voxelSize*(latticeSizeY); boundingBoxSupport1["max"]["z"]= voxelSize*(latticeSizeZ); setup["supports"]=[ [boundingBoxSupport1,dof] ]; ######################### 2.d. Loads ######################### #### 2.d.1 Static Loads load1=Dict() load1["x"]=0.0 load1["y"]=0.0 load1["z"]=0.0 boundingBoxLoad1=Dict() boundingBoxLoad1["min"]=Dict() boundingBoxLoad1["max"]=Dict() boundingBoxLoad1["min"]["x"]=voxelSize*(latticeSizeX-1); boundingBoxLoad1["min"]["y"]=0; boundingBoxLoad1["min"]["z"]=0; boundingBoxLoad1["max"]["x"]=voxelSize*(latticeSizeX); boundingBoxLoad1["max"]["y"]=voxelSize*(latticeSizeY); boundingBoxLoad1["max"]["z"]=voxelSize*(latticeSizeZ); setup["loads"]=[ [boundingBoxLoad1,load1] ]; setup["fixedDisplacements"]=[]; #### 2.d.2 Dynamic Loads function floorEnabled() return false end function gravityEnabled() return false end function externalDisplacement(currentTimeStep,N_position,N_fixedDisplacement) return N_fixedDisplacement end function externalForce(currentTimeStep,N_position,N_force) if currentTimeStep>1000 return Vector3(0,0,0) else return N_force end end # if no temperature: # function updateTemperature(currentRestLength,currentTimeStep,mat) # return currentRestLength # end function updateTemperature(currentRestLength,currentTimeStep,mat) if currentTimeStep<1000 temp=-5.0*currentTimeStep/1000 currentRestLength=0.5*mat.L*(2.0+temp*mat.cTE) elseif currentTimeStep==2500 temp=0 currentRestLength=0.5*mat.L*(2.0+temp*mat.cTE) end return currentRestLength end