AbstractNecessity of mobility of goods and people for economic development of a country has unleashed a boom in vehicle population in developing countries like India. Because of large economic disparity in the society, 2-wheelers on the road outnumber 4-wheelers almost 5:1. Using crowded roads, poor condition of roads and undisciplined traffic requires frequent starts and stops – some of them very abrupt. Pitching-over of 2-wheelers under such “panic braking” manoeuvre puts vast number of 2-wheeler riders under risk of sustaining severe injury as during pitch-over rider is thrown over the handle bar.
In the work presented here, key operational parameters responsible for pitch over of a motorcycle, and their relative influence on the phenomenon have been identified. “Pitch-over” envelope, to define unsafe zone, in terms of these parameters has been defined.
Mathematical models using analytical solutions were used to identify the key operational parameters influencing the pitch-over tendency of motorcycles. Relative effects of these parameters, like travel velocity, braking duration, brake bias, road gradient, and road friction coefficient, on threshold of pitch-over were studied using ADAMS model. This model was validated against available test results for some standard manoeuvres.
Duration of application of brakes, deceleration, was found to be the most important parameter for pitch-over. Motorcycle deceleration increases non-linearly with reduction in duration of braking. With adequate time, > 2 s in this case, tendency of pitch over is negligible. However, as available time reduces to 1 s or lower, a realistic scenario on a crowded street, motorcycle will have a tendency to pitch-over even at speeds lower than 40 km/h. This highlights the importance of developing a pitch-over control system for motorcycles operating in cities of developing countries.
|Date of Award||2014|
|Supervisor||Vinod K. Banthia (Supervisor), S. R. Shankapal (Supervisor) & Mike Blundell (Supervisor)|
- road safety