Simulating the Effects of a Virtual Motorcycle Passenger on Vehicle Motion and Rider Effort

Motorcycles, bicycles, and other single-track vehicles are popular but dangerous methods of transportation. While some are piloted by only a single rider, many powered two-wheelers are ridden with a passenger, who may also significantly influence the vehicle's dynamics. Because simulations are a critical component of vehicle safety research, this paper asks whether a simulated, active “virtual passenger” has stabilizing or destabilizing effects on a rider-vehicle-passenger system. This virtual passenger exerts its control effort by moving an inverted pendulum to simulate the motion of a human passenger's torso without explicit knowledge of rider inputs. A battery of simulations in the nonlinear, multi-body Webots robot simulator show that the passenger's control efforts have mixed effects on both rider effort and vehicle stability over abrupt transitions in pavement height. This indicates that the inclusion of passenger motion may be critical when vetting the safety of roadway designs and/or emerging motorcycle technologies like Advanced Rider Assist Systems.