Data for Evaluation of Crash Test Dummies and Human Body Models: New and past Post Mortem Human Subject Data from Groupement d'Intérêt Economique de Recherches et Etudes PSA-RENAULT; and Volunteer shoulder range-of-motion and stiffness
For assessment of their performance and for the development of injury risk functions there is a need for additional biofidelity data. In this report two types of data are made available: Part A - post mortem human subject exposed to various restraints; Part B – volunteer shoulder rang-of-motions.
Load-limiting belt restraints have been present in cars since 1995. An accident study showed the greater effectiveness in thorax injury prevention using a 4 kN load limiter belt with an airbag than using a 6 kN load limiter belt without airbag.
Frontal sled crashes were performed using PMHS. Restraint conditions evaluated are 6 kN load-limiting belt and 4 kN load-limiting belt with an airbag. Loads between the occupant and the sled environment were recorded. Various measurements characterize the PMHS behaviour and injuries were noted.
Many studies have reported multiple rib fractures sustained by an Out-of-Position (OOP) driver subjected to a frontal airbag deployment. Two successive phases occur during the bag deployment: punch-out loading of the thorax, followed by a membrane effect. The aim of this study was to investigate the thoracic injuries generated by each phase separately.
Tests of nine post-mortem human surrogates were carried out on a static test bench using a driver side airbag module. Three loading configurations were performed: membrane only, punch-out only, and both types combined. The membrane-only tests were performed with the thorax initially positioned at 13, 78 and 128 mm from the plate in order to vary the load magnitude. The punch-out and the combined tests were performed with the thorax initially 8 mm from the module. Accelerometers and angular rate sensors were fixed on the sternum and on the first, fourth, and eighth thoracic vertebrae of the PMHS. Ribs 2 to 6 were instrumented with strain gauges. The reaction force of the bag on the plate was measured using four 2-axis load cells.
Results showed that both pure punch-out and pure membrane loading can result in thoracic injuries. However, the rib fracture locations seemed to differ from one type of loading to the other. Moreover, for the same initial distance between the airbag module and the thorax, the injuries were more severe in the combined effect tests than in the pure punch-out or pure membrane.
Ribs of 8 PMHS were equipped with up to 96 strain gauges. In a first series of 3 tests, the subjects were seated upright and their chests were loaded by a 23.4 kg impactor propelled at 4.3 m/s in pure frontal, oblique and pure lateral directions. In a second series of 3 tests, the subjects were loaded by the deployment of an unfolded airbag in the same 3 directions.
The shoulder complex is rarely exposed to injuries in frontal and oblique frontal collisions, but influence the belt interaction and as such the thorax compression and head kinematics. The purpose of this study was to establish response requirements for the shoulder complex in terms of range-of-motion and stiffness.
Six male volunteers were seated in a rigid seat that simulated a car driver’s posture whilst in a special designed test rig. Loads to the shoulders were applied through the arms, by means of brackets fastened to the elbows, loads rearward were applied by means of a strap around the shoulder complex. Torso movement was blocked by two pre-tensed diagonal belts that were routed close to the neck to avoid excessive clavicle interaction. Shoulders were loaded with increasing load from 0 ̶ 200 N/shoulder at 50 N increments. A test series included four load series: shoulders pulled straight forward, forward-upward, upward and rearward. Each volunteer was exposed to three tests.
Shoulder positions relative to the spine were obtained from film analysis. Photo markers were mounted on the volunteer’s skin: head, posterior tip of acromion process, chest, T1 and T4. The right and left acromion relative to T1 displacements were used to calculate the shoulder range-of-motion in three directions. Belt loads and seat back loads were recorded.
Average resultant volunteers’ acromion relative to T1 range-of-motion, at the maximum load, was 55 mm for forward loads, 69 mm for forward-upward loads, 73 for mm upward loads and 50 mm for rearward loads. The volunteers provided measurements with reasonable repeatability.
The volunteers curved their spines only slightly when shoulder loads were applied. Hence, shoulder complex motion was successfully isolated and results reflect pure shoulder relative to chest motions.
The applied loads were lower than those commonly seen in frontal crashes, however the shoulder is highly mobile and its response to loads is largely dependent on muscle characteristics. As such studies using volunteers may be complimentary to tests with post mortem human subjects.