Dual Stage Front Underride Protection Devices (dsFUPDs): Collision Interface and Passenger Compartment Intrusion

A performance investigation of Front Underride Protection Devices (FUPDs) with varying collision interface is presented by monitoring occupant compartment intrusion of Toyota Yaris and Ford Taurus FEA models in LS-DYNA. A newly proposed simplified dual-spring system is developed and validated for this investigation, offering improvements over previously employed fixed-rigid simplified test rigs. The results of three tested collision interface profiles were used to guide the development of two new underride protection devices. In addition, these devices were set to comply with Volvo VNL packaging limitations. Topology optimization is used to aid engineering intuition in establishing appropriate load support paths, while multi-objective optimization subject to simultaneous quasi-static loading ensures minimal mass and deformation of the FUPDs. While a new FUPD is developed and tested which highlights benefits of deflecting the passenger vehicle in small overlap cases, a dual stage FUPD is proposed revealing potential benefits in utilizing the radiator to absorb some collision energy. The devices developed extend beyond ECE R93 allowable measurement values from the front of the tractor, to comply with the aerodynamic shape of the tractor bumper, and resultant performance is assessed.