Fuel consumption in a driving test cycle by robotic driver considering system dynamics

Abstract

In vehicle performance tests, fuel consumption, the components of exhaust gas, and mileage are measured on a chassis dynamometer that simulates the road load. It is difficult even for a professional driver to maintain speeds within the tolerance band of driving test cycles. Thus, there has long been an expectation that robotic drivers will be able to test vehicle performance with high reproducibility. In previous studies of robotic drivers, the improvement of tracking performance has been studied for each driving test cycle. In this study, we proposed a control system for realizing a driving test with smooth pedal use and low fuel consumption. We derived a set reference speed profile within a tolerance band from a driving test cycle standard. First, we performed a vehicle pre-test with a professional driver. From this driving test, we found that the square value of the power consumed by the vehicle was effective for driving with smooth pedal operation. Therefore, we proposed an objective function considering the square value of the power. We then derived the reference speed in a driving test cycle tolerance band for the robotic driver by the proposed method. Finally, we performed the vehicle test using the robotic driver. In the test, we used a standard JC08 chassis dynamometer, a moving averaged JC08 waveform, and the proposed speed waveform. We made sure that the proposed system was effective using the results of the actual vehicle tests.