Design and realization of an open-loop simulator for ICE control unit, developing the crankshaft and camshaft sensors simulation

Automotive industry focuses its efforts to increase human safety and to reduce fuel consumption and pollutant emissions, in order to be in compliance with the more and more stringent environmental requirements imposed by governments. A large number of new electronic systems have been being developed over the years and Electronic Control Units (ECUs) represent the brain of the vehicles. Also internal combustion engine is mainly governed by embedded systems: the Engine Control Module manages the powertrain system, by controlling air-fuel ratio, fuel injection and ignition. The high complexity of the electronic architecture of a vehicle requires a time consuming and costly phase of simulation for verification and validation of the system. In this scenario, Hardware-in-the-Loop (HIL) simulation is performed to validate the real-time software running in ECUs, but some automotive companies do not need a whole HIL simulator to perform simple tests. Hence, an open loop crankshaft and camshaft sensors simulator can be used in order to simulate the four-stroke engine behaviour and the purpose of this master thesis is its design and realization. Firstly, a review of the working principle of a diesel internal combustion engine is presented. Furthermore, details about embedded systems, ISO-26262 and its V-model for software development are given, in order to see how it is possible to design and validate safety-related systems for automotive electrical systems. The first part of this project deals with the study of the main characteristics of a HIL simulator for powertrain, in order to understand how it generates the crankshaft and camshaft signals useful for the ECM. Starting from this study, the design and realization of the open-loop simulator is performed: the generated signals are digital, since they represent the output of a Hall-effect active sensors. The implemented simulator is made up of some electronic devices: an high-performance microcontroller, a rotary encoder for setting the desired engine speed value for the simulation and a touch display used as graphical user interface. The application code is written in C-language: it contains the look-up table describing the crankshaft and camshaft pattern and all the I/O peripherals configurations (modules used to control the quadrature encoder, real-time interrupt, serial communication protocol and general input-output channels). As result, the digital signals are generated according to the real-time user settings and they are verified using an oscilloscope.