Repairing assessment on damageability of a vehicle is done by analyzing the damage itself and repairing costs for the damage that collisions caused. Korea, as it is in European countries, uses RCAR low speed collision test as a standard when analyzing. RCAR has announced its new plan to implement a new set of tests that includes bumper barrier tests in addition to existing structure tests.
In order to adjust for the new RCAR test, it is more than necessary to adopt crush box technology; also, strength of bumper beams need to be brought up to match that of the North American version. In this report, a new system developed by introducing a new design to meet the RCAR requirement has been analyzed. The new structure which consists of crash boxes installed on existing performance-proved North American GMT beam has been assessed. All the adjustment and new development have been initiated in purpose of passing newly erected RCAR test. A structural analysis and vehicle tests were done on a compact vehicle to test the performance of this system.
Through structure analysis, an optimum system that satisfies RCAR structure test and bumper barrier test has been designed. Performance verification was carried out by the vehicle test, and materials and the shape of plastic crush box was optimized at first. Plus, member strength and shape of the weight curve were obtained by using the finally chosen crush box system.
Though design and strength of the beam are two most important factors in bumper barrier performance, due to lack of time, instead of using the design of the beam that was used in structural analysis, a beam that was modified from the existing beam was used in the vehicle test. Though intrusion value came out larger than the analysis result, owing to variation in the shape and weight, only very small defection, a small crack at the bottom center of the beam, was found.
Through this analysis, it was witnessed that the new light-weight bumper system appropriate for the new RCAR test can be developed by constructing a new design and materials of the plastic and steel crush box.