Rate-Limited and Energy-Efficient Feedforward Control for Multi-Fuel Unmanned Aircraft Systems Engine

Surrogate-model or data-driven model-based control frameworks are becoming increasingly popular in recent years due to their ease of model development and enhanced computational power, making them suitable for real-time use. However, when it comes to modeling aspects related to time, difficulties arise as many of the models deal with quasi-static systems. In this paper, we propose a method to model time-dependent actuator constraints in a surrogate-model-based control framework for controlling the combustion phasing in a multi-fuel UAS engine. Along with this, a conducive method for designing an energy-efficient ignition assistant control is discussed. The developed methods are then tested on a diesel engine, and the results show a more robust and energy-efficient combustion phasing control as the fuel property varies in real-time.