Kim, S., McPhee, J., and Lashgarian Azad, N., "Improving Stability of a Narrow Track Personal Vehicle using an Active Tilting System," SAE Technical Paper 2014-01-0087, 2014, doi:10.4271/2014-01-0087.
A compact sized vehicle that has a narrow track could solve problems caused by vehicle congestion and limited parking spaces in a mega city. Having a smaller footprint reduces the vehicle's total weight which would decrease overall vehicle power consumption. Also a smaller and narrower vehicle could travel easily through tight and congested roads that would speed up the traffic flow and hence decrease the overall traffic volume in urban areas. As an additional benefit of having a narrow track length, a driver can experience similar motorcycle riding experience without worrying about bad weather conditions since a driver sits in a weather protected cabin. However, reducing the vehicle's track causes instability in vehicle dynamics, which leads to higher possibility of rollovers if the vehicle is not controlled properly.A three wheel personal vehicle with an active tilting system is designed in MapleSim. The vehicle is driven by constant rotational input which is applied to the rear wheel. Simulation results indicate that for the case when the tilting vehicle is moving at 45 km/h and the front wheel's steering angle is 4°, the resulting turning circle's diameter without rollovers is found to be 9.5 m less than the non-tilting vehicle moving at the same condition as the tilting vehicle.