Design evolution of novel rear sub frame structure for multilink suspension and electric vehicle platform

As there is a major shift in customer demand for energy efficient transportation electric vehicle development has taken immediate significance worldwide as they provide pollution free, noise free mobility environment. In the current work, the authors evaluate novel Rear sub-frame assembly structure with multilink suspension and further for a born electric vehicle platform with increased rear axle weight contribution due to rear motor and battery weight. The Sub Frame is the important structural component of the chassis system. Hence designers face the challenge of providing a best-in-class optimized Rear sub-Frame in terms of cost and weight within the available vehicular boundary. Rear sub-Frame assembly is designed with unique cross member structure and novel motor mounting arrangement on the side member with the given complex hard points or attachments of the suspension linkages, to meet the electric vehicle packaging requirement. Sub frame is designed with light weight to withstand the 20 % higher vehicle weight compared to the usual internal combustion engine vehicle. Weight of the sub frame has been optimized by using the lower thickness of sheet panels of 1.6mm with optimal grade material to reduce the weight by 10 % without compromising with the NVH and Durability targets. In the present study involves detailed design evolution of Rear sub-Frame with unique structural arrangement and novel integrated motor mounting arrangement. and designed with optimal grade low thickness material with optimistic arrangement of reinforcement and baffles to achieve required strength for superior CAE - NVH performance. Meeting packaging requirements and weight target. Keywords: Rear sub-Frame assembly, Unique structural arrangement, Novel motor mounting arrangement, High grade low thickness material.