Measurement of Head Angular Acceleration in Crash Tests: Development of an Electronic Device for the Hybrid III Dummy

A new approach has been developed to facilitate the measurement of head angular acceleration in automobile crash tests. It consists of two parts: an array of 12 linear accelerometers mounted in a Hybrid III dummy head and an electronic signal processor mounted on the dummy spine. The accelerometer outputs are led to conventional data acquisition equipment and also to the signal processor which digitizes the raw acceleration signals, stores them, and computes the 3-D angular acceleration. This acceleration and the 3-D linear acceleration of the head c.g. are available in real time or post test. The equipment has been evaluated on a mini-sled, with various configurations of head loading and kinematics, and also in Hyge sled tests performed at 40 km/h with a 3 point belted Hybrid III dummy. The angular accelerations returned by the signal processor in both test settings corresponded closely to those computed off-line from the raw data.