Comparison of exhaust gas emissions between autonomous and human operator excavator

Abstract

<div lang="en" class="abs"><p class="abs_header">Abstract</p><p>The scope of this study was to compare the exhaust gas emissions of an autonomous driving and a human operator excavator under real construction work conditions. The test diesel engine excavator with EPA 2012 emission regulations rules (Tier 4final/Stage IIIB) has an engine power of 44.3 kW at an engine speed of 2100 rpm. In addition, it has various devices, such as exhaust gas recirculation (EGR) and diesel particle filter (DPF), to reduce the engine-out emissions. The exhaust gas emissions, including carbon dioxides (CO₂) and nitrous oxides (NO_x), were measured with a portable Gasmet DX4000 FTIR gas analyser and analysed with Calcmet software. Pressure transmitter with digital output by G2 6DOF IMU by Novatron was used to check the pressure and angular variations, respectively. In addition, FLIR E60 IR Camera was used to visualize the exhaust gas during the chilly winter experiment conditions.</p><p>The exhaust gas tests were carried out in a simple move of bucket with autonomous driving and repeated with a human operator. For both tests, the movement of the bucket was done in 0%, 50% and 100% engine speed positions. In autonomous driving, autonomous trajectories were generated in the Rhino Grasshopper environment. Based on the emission analysis results, the CO₂ emission was lower during autonomous driving than during human operation. The same trend was also seen in the case of NO_x emissions. The human operator used a higher movement speed and a slightly different movement compared with autonomous driving, which may explain the difference in emissions.</p></div>