Stability and Handling of a Three Wheeled Personal Vehicle

It has been predicted that the prevailing COVID-19 situation would result in increased demand for personal vehicles. There is a renewed interest in the 3 wheeled vehicles for short urban mobility in western countries due to their inherent cost advantages which will make it affordable for the common man. As the world is moving towards electric vehicle technology, a light 3 wheeled vehicle option will also help in reducing battery weight and thereby help in addressing the range concerns. In addition, slow speed 3-wheelers need not pass extensive safety regulation tests in many western countries including the USA.

Three-wheeled vehicles are not new to developing countries like India as three-wheeled auto-rickshaws are quite popular for short distance shared travel. The existing single front wheel design known as delta design may have a stigma attached to it due to historic reasons in India. There is also a perception that the three-wheeled vehicles are highly unstable. Therefore, the current paper studies in detail an alternate design known as the tadpole design having two wheels in the front. The tadpole configuration facilitates decent styling and good aerodynamics. The tadpole configuration is modeled and analyzed using CAE multibody dynamics software, MSC Adams Car. To get confidence in the simulation results, a few benchmarked and tested vehicles are selected from the available literature [1] and the MBD results are compared for correlation. The studies also include a standard four-wheeled vehicle and a delta configuration 3-wheeler for reference purpose. The MBD virtual analyses provide results for vehicle stability and handling characteristics like overturning speed limit, oversteer and understeer behavior during constant radius cornering tests. The paper, by keeping in mind the typical urban driving condition and pattern, gives its feedback and recommendation about the tadpole configured 3-wheeler.