One of the most important problems for our planet is the pollution produced in the transport sector. Over the years, increasingly stringent regulations have been imposed on the pollutants production because of the damage that these bring to the human health and to the environment. In this thesis, I analyzed the production of Particulate Matter (PM) within Compression Ignition Engines (IC) and the after-treatment systems (ATS). In particular, my work is based on the construction of a virtual sensor based on Machine Learning algorithms for the On-Board Driving (OBD) prediction of the Soot Tail pipe produced in a Diesel Engine. Such system was completed, building a Predictive Artificial Neural Network (ANN) in python, using calculation models belonging to the Deep Learning branch.