Evaluating the Impact of Velocity Advisory Systems on Fuel Economy of Passenger Vehicles: A Driver Simulator Study

With increasing emphasis on sustainable mobility and efficient energy use, advanced driver assistance systems have become a pivotal research area to improve fuel economy in vehicles. In this context, real-time advisory systems have the potential to enhance the energy efficiency of vehicles by influencing driver behavior. Despite the growing adoption of such systems in passenger vehicles, systematic studies examining the effects of human driving on vehicle energy efficiency and energy use remain scarce. This study investigates the effects of a driver velocity advisory system on the energy use in a plug-in hybrid electric vehicle through a controlled experiment using a driving simulator. A mixed urban-highway driving environment was reconstructed to observe the human driver’s behavior without and with driving assistance. The advisory system provided drivers with an optimized speed profile, pre-calculated for the simulated route to achieve maximum energy efficiency. Participants were instructed to navigate the simulated route while the vehicle's powertrain parameters, energy consumption, and overall dynamics were monitored. In the unassisted condition, drivers operated the vehicle according to their natural driving style. In the assisted condition, real-time velocity advice was given to provide a more energy-efficient driving strategy through visual feedback to the drivers. The results obtained analyze the impact of speed advisory systems on vehicle dynamics, powertrain use and energy consumption metrics. The assisted driving condition resulted in smoother driving patterns, optimized powertrain operation, and notable fuel economy improvements compared to unassisted driving.