[Reflection.Assembly]::LoadWithPartialName("Microsoft.AnalysisServices")>$Null;cls
$sasvr=New-Object Microsoft.AnalysisServices.Server;$sasvr.Connect("YourServer") 
$db0="Roles_Clone_Source_SSAS_DB";$cub0="YourCubeID"
$db1="Roles_Clone_Dest_SSAS_DB";$cub1=$cub0
foreach($cperm0 in $sasvr.Databases[$db0].Cubes[$cub0].CubePermissions){
$cperm1=$sasvr.Databases[$db1].Cubes[$cub1].CubePermissions.Add($cperm0.RoleID)
$cperm1.RoleID=$cperm0.RoleID
$cperm1.Name=$cperm0.Name
$cperm1.ID=$cperm0.ID
$cperm1.Read=$cperm0.Read
$cperm1.Write=$cperm0.Write
$cperm1.ReadDefinition=$cperm0.ReadDefinition
$cperm1.ReadSourceData=$cperm0.ReadSourceData
$cperm1.Process=$cperm0.Process
foreach($dperm0 in $cperm0.DimensionPermissions){
$dperm1=$sasvr.Databases[$db1].Cubes[$cub1].CubePermissions[$cperm0.ID].DimensionPermissions.Add($dperm0.CubeDimensionID)
$dperm1.Read=$dperm0.Read
$dperm1.Write=$dperm0.Write
foreach($aperm0 in $dperm0.AttributePermissions){
$aperm1=$sasvr.Databases[$db1].Cubes[$cub1].CubePermissions[$cperm0.ID].DimensionPermissions[$dperm0.CubeDimensionID].AttributePermissions.Add($aperm0.AttributeID)
$aperm1.AllowedSet=$aperm0.AllowedSet
$aperm1.DeniedSet=$aperm0.DeniedSet
$aperm1.DefaultMember=$aperm0.DefaultMember
$aperm1.VisualTotals=$aperm0.VisualTotals
}}$cperm1.Update()}
$sasvr.Disconnect();$sasvr.Dispose();Remove-Variable sasvr