Frontal Impact Responsesof Generic Steel Front Bumper Crush Can Assemblies 2014-01-0550
The present investigation details an experimental procedure for frontal impact responses of a generic steel front bumper crush can (FBCC) assembly subjected to a rigid full and 40% offset impact. There is a paucity of studies focusing on component level tests with FBCCs, and of those, speeds carried out are of slower velocities. Predominant studies in literature pertain to full vehicle testing. Component level studies have importance as vehicles aim to decrease weight. As materials, such as carbon fiber or aluminum, are applied to vehicle structures, computer aided models are required to evaluate performance. A novel component level test procedure is valuable to aid in CAE correlation.
All the tests were conducted using a sled-on-sled testing method. Several high-speed cameras, an IR (Infrared) thermal camera, and a number of accelerometers were utilized to study impact performance of the FBCC samples. A linear potentiometer was installed next to each crush-can to directly measure crush length of the can. In addition, applied force upon impact was directly measured using load cells. The objective of this study is to examine the frontal-impact performance of an FBCC structure - as a component of a vehicle structure. This includes validating the data obtained from different devices such as accelerometer, load wall, potentiometer, and high-speed camera.
Comparison of displacement and velocity time-histories from video tracking and accelerometers showed good agreement. In addition, displacement time-histories of potentiometers and accelerometers were in good correlation. The results showed that the force time-histories obtained from Newton's second law and direct load measurements were in excellent agreement. Consistent deformation and failure modes were observed. Energy absorbed in each test was within a tight band as compared to the other tests. Heat was generated and dissipated at the can tip and further heating was observed as the can continued to fold.