An Architecture for Real-Time Estimation of Crank-Angle-Resolved Engine Cylinder Pressure

Abstract

This work presents a custom hardware architecture for crank-angle-resolved engine cylinder pressure estimation that can accept inputs such as speed, manifold pressure and throttle position, and deliver cylinder pressure in real-time, at engine speeds covering the useful operating range of most engines (up to 10,000 rpm). The hardware, placed in a reconfigurable embedded system for real-time validation, was tested using results of a model derived from actual engine data (13 sets). The hardware, implemented in 32-bit Dual Fixed-Point arithmetic, exhibits results that are very close to those of a 64-bit floating-point software model. This work attempts to show Dual Fixed-Point as a good alternative for high precision operations in automotive applications, where floating point is believed to be the only option.