Investigation of the Behavior of Three-Wheel Vehicles When They Pass Over a Low μ Road Surface

Abstract

In recent years three-wheel camber vehicles, with two wheels in the front and a single rear wheel, have been growing in popularity. We call this kind of vehicle A "Leaning Multi Wheel category Vehicle" (hereinafter referred to as a "LMWV"). A LMWV has various characteristics, but one of them stands out in particular. When a LMWV is cornering, if one of the front wheels passes over a section of road surface with a low friction coefficient, there is very little disturbance to the vehicle's behavior and can continue to be driven as normal. However, there has been no investigation into why these vehicles have this particular characteristic. Consequently, in this paper an investigation was carried out in order to determine the behavior of a LMWV in this situation. First, measurements were taken using an actual vehicle to confirm the situation described above. As a result, it was confirmed that there is only a small change in the vehicle's posture and also that the other front tire generates tire force that appears to compensate for the decrease in lateral force. Next, a multibody dynamics analysis was carried out. The results of this simulation indicated that the cause of this phenomenon is the steering turns toward the inside of the corner and the other front tire develops a slip angle which in turn generates a lateral force. The investigation and analysis described above clarified this phenomenon and demonstrated one of the factors that gives a LMWV its cornering stability.

Design and Structural Analysis of a Front Single-Sided Swingarm for an Electric Three-Wheel Motorcycle

“…Other researchers are focused on the effects of passing over low friction coefficient surfaces, where the riders of three-wheel vehicles have indicated that one noteworthy characteristic is the vehicle's stability when cornering, over a low friction surface, like slippery or wet road. As indicated, under these conditions the decrease in lateral force on one front tire, passing over the low friction road surface, is compensated by the other front tire [9].…”

“…In general, tire friction data are linked to road conditions (dry, wet, ice), as also on different road material types (such as asphalt, gravel etc.) [7,9,27]. Nevertheless, motorcycle tires are different than car tires and have different shapes of contact patch on the road [27,28].…”

Efficient Gear Ratio Selection of a Single-Speed Drivetrain for Improved Electric Vehicle Energy Consumption

“…Such data are mainly related to road conditions (dry, wet, or ice), as also on different road material types (such as asphalt, gravel, etc.) [40][41][42]. Experimental and theoretical results for car tires in contact with a road made from tarmac in dry conditions can be found in [42,43], presenting a range of values 0.7 < µ < 1.0.…”