Stability and Control Analysis of a Scooter

In India, scooters are now being increasingly used by young women because of its lesser weight and ease of riding. Prevalent riding conditions demand higher stability and manoeuvrability at low speeds, which could be achieved by an in-depth study. A virtual handling model of the scooter has been developed using multibody analysis software for studying the stability and manoeuvrability. Realising the role of tyre properties on the stability characteristics of two-wheelers, a new tyre model that can simulate combined slip conditions has been developed and used in the scooter model. A robust steering controller has been used for maintaining the desired path of the scooter. The virtual model has been analysed under linear and non-linear conditions for both straight running and cornering manoeuvres. The stability characteristics of the scooter have been studied by root locus and eigenvector analysis. The consistency of the model has been verified by a brief plausibility study. Vibrational modes of the scooter have been identified and studied. A very important design criterion has been identified and its effect on rider's perception of the scooter recognised. Predicted results were found to match with experimental data and rider perception.