Balaji, G., Agarwal, A., Mungi, M., Babar, R. et al., "A New Approach to Vehicle Design and Development Using “HYBRID MULE” for Platform Strategy," SAE Technical Paper 2013-01-2360, 2013, doi:10.4271/2013-01-2360.
In automotive design and development, there are different stages for product design.In this fast changing scenario product design, digital verification of design (CAE), physical validation of the product and launching of the same in short time is important in product development life cycle of any new generation vehicle.This paper proposes a new approach towards development of a green-field platform for commercial vehicles by improving reliability of CAE and thereby reducing the need for prototype testing and hence shortening development cycle and costs - we call it “Hybrid Mule”. This Hybrid Mule has complete design intent under-body and engine-house while upper-body is made of simple representative tubular space frame. FRP skin panels are attached to this space frame to create a safe environment for test-driver. FRP skin also provides early feel of styling in running condition and evaluates basic ergonomics and visibility.Hybrid Mule is developed taking into consideration all detail CAE analyses - durability, crash, NVH, attachment point stiffness, ride & handling, etc., to establish early co-relation between digital and physical worlds. Such a concept helps in platform-sharing across diverse upper-bodies developed based on market and style requirement.Basic skeleton in upper-body (simple-to-construct tubular space-frame) can be changed based on basic shape changes required by new style while retaining the same platform- sharing under-body.This methodology also helps in reducing the number of prototypes leading to effective cost and time saving in prototype manufacturing and testing phases.This concept of “Hybrid Mule” - design-intent under-body with tubular space-frame upper-body - as further explained below - effectively results in elimination of Alpha-prototypes and one can directly move from mule to Beta-prototypes with high level of confidence.