Design of a McPherson Strut Based Split Link Front Suspension for a Higher Rear to Front Weight Ratio SUV with Least Turning Circle Diameter

Generally, in an electric sports utility vehicle with rear mounted powertrain the mass distribution is greater in the rear compared to front. This higher rear to front weight distribution results in oversteer behavior during high-speed cornering deteriorating vehicle handling & risking passenger safety. To compensate this inherent oversteer nature of such vehicles & produce understeer behavior, the steering rack is placed frontwards of the front wheel center for toe-out behavior due to lateral compliance during cornering. This compensation measure results in lower Ackermann percentage resulting in higher turning circle diameter deteriorating vehicle maneuverability.

This paper proposes a design to obtain ideal understeer gradient with minimal turning circle diameter through utilization of split link technology with a McPherson Strut based suspension framework & frontwards placed steering rack. This suspension is utilized in our Mahindra Inglo platform. This paper elaborates on how through split links, variable knuckle length arm can be achieved which helps in achieving greater outer to inner wheel steering turn angle rate effectively improving Ackermann percentage & minimizing turning circle diameter.

Apart from that the design mentioned herein allows greater manipulation of longitudinal & lateral compliance due to partial decoupling of both by split links. This overall improves longitudinal compliance resulting in better plushness during bumps improving ride without compromising handling characteristics of the vehicle. The suspension design is also optimized for wheel travel of 185mm, higher than benchmarks to provide enough wheel traction as well as comfort on hilly terrains & city roads of India.