Motorcycle Accelerations while Successfully Traversing Roadway Irregularities and Traffic Calming Devices (Speed Bumps) at Small Lean Angles 2019-01-0434

There have been limited empirical studies regarding the dynamics of a motorcycle and rider as a motorcycle traverses a roadway irregularity such as a pothole or depression, or a traffic calming device (TCD) such as a speed bump. This study seeks to establish qualitative analysis of the success of motorcycles traversing various roadway irregularities and TCDs as well as quantitatively analyzing three-axis accelerations to both the motorcycle and the rider at varying speeds and small lean angles. Further analysis is conducted comparing the accelerations experienced in scenarios where the suspension of the motorcycle experiences extension followed by compression, as is the case when encountering a pothole or depression, as well as scenarios where the suspension of the motorcycle experiences compression followed by extension, as is the case when encountering a TCD. Largely, the study is to establish values for both speeds and lean angles in which traversing roadway irregularities and TCDs causes little to no dynamic instability to the motorcycle and little to no discomfort to the rider. The roadway irregularities and traffic calming devices are traversed perpendicularly and at lean angles within 5 degrees of vertical. Roadway irregularities and TCDs are measured utilizing 3-dimensional laser scanning to establish the length, depth, and contour (slope) of the irregularities and/or traffic calming devices. The motorcycle speeds, accelerations, and lean angles are obtained through four different on-board data logging devices. The results of this testing quantitatively and qualitatively establishes that the tested motorcycle was successfully able to traverse a variety of roadway irregularities and TCDs at speeds up to at least 30 mph and lean angles up to at least 5 degrees. Further testing at higher speeds and steeper lean angles is yet to be performed.