'Maya'
Email: einollahia@gmail.com
4: Using the Extract tool, divide your model into 3 parts.
5: Perform these steps for all 3 parts: Select the boundary of your model with the edges on the corner of your model.
6: Select Bevel and set its value to 0.2
7: Duplicate your model, according to the X, Y and Z axes. Finally, perform smooth or sub_d.