Validation of the PC-Crash Single-Track Vehicle Driver Model for Simulating Motorcycle Motion 2024-01-2475

This paper validates the single-track vehicle driver model available in PC-Crash simulation software. The model is tested, and its limitations are described. The introduction of this model eliminated prior limitations that PC-Crash had for simulating motorcycle motion. Within PC-Crash, a user-defined path can be established for a motorcycle, and the software will generate motion consistent with the user-defined path (within the limits of friction and stability) and calculate the motorcycle lean (roll) generated by following that path at the prescribed speed, braking, or acceleration levels. In this study, the model was first examined for a simple scenario in which a motorcycle traversed a pre-defined curve at several speeds. This resulted in the conclusion that the single-track driver model in PC-Crash yielded motorcycle lean angles consistent with the standard, simple lean angle formula widely available in the literature. The PC-Crash calculations did not account for the width of the motorcycle tires and their influence on the required lean angles. Also, PC-Crash did not utilize counter-steering to generate the initial lean when entering a curved path. Thus, the steering inputs generated by the simulation should not be interpreted as those an actual rider would utilize.

Second, the model was utilized to simulate instrumented real-world driving of a motorcycle around a series of curves. This helped to establish reasonable inputs for the model and demonstrated that the model’s calculated lean angles were reasonable. Again, the results were consistent with the basic lean angle equation, not accounting for the influence of tire width. Steering inputs were not documented for the real-world driving, and so, no comparison was made between the real-world steering inputs and those generated by PC-Crash. However, the model again did not utilize counter-steering to generate lean, and so it is unlikely that the steering inputs generated by PC-Crash would match the real-world steering inputs. Still, the PC-Crash single-track driver model will yield results that are typically adequate for a crash reconstruction or visualization. Reconstructionists generally do not need to know the precise steering inputs used by a motorcycle rider. In instances where a crash could have been caused by a rider leaning their motorcycle to the geometric limit, the results from PC-Crash might need to be adjusted for tire width to ensure accurate conclusions.