Analysis of the Off-Road Performance of a Vehicle Equipped with an Aero-Compensator

Abstract

All types of vehicles must possess off-road capabilities, as any vehicle may encounter the need to leave a paved road, traverse damaged sections of roads, drive on dirt detours around repaired or constructed sections of roads and bridges, or travel in winter over uneven, snow-covered roads.

For vehicles that systematically operate under severe road conditions, off-road performance is of primary importance. These include, first and foremost, military medium- and light-duty trucks, small buses, passenger cars, and other vehicles used in rural or forested areas, as well as dump trucks used in the construction of large hydraulic structures, road construction, and other construction projects. The average driving speeds, productivity, and preservation of vehicle mechanisms largely depend on the off-road capabilities of these vehicles.

This article analyzes the dependence of wheel rolling resistance on the main parameters of the wheel and the soil. Graphical dependencies are constructed showing the rut depth, resistance force, and rolling resistance coefficient as functions of soil compaction and moisture for soft soils. An obstacle classification and analysis of vehicle off-road performance considering their profile properties are carried out. Key performance indicators of off-road capability are identified. Based on an analysis of the factors that improve off-road performance, it is established that vehicle mobility on rough terrain can be enhanced by reducing the vertical load on the support surface. This can be achieved by combining a wheeled propulsion system with an aero-compensator (a directional air fan). Preliminary calculations show that the difference in wheel load between a vehicle without an aero-compensator and one equipped with it is approximately 10–15%.

Keywords: vehicle off-road performance, wheel rolling resistance, vertical wheel load, vertical load aero-compensator, obstacle classification.