The risk of injury from torso side airbags in out-of-position (OOP) scenarios is assessed using stationary occupant conditions. Although stationary tests have been effective in frontal airbag assessments, their applicability to torso side airbags remains uncertain. Using the MADAYMO facet occupant model, thoracic OOP injury was evaluated using full-chest compression criteria (%C) and viscous criteria (VC) under stationary occupant conditions and occupant impact velocities of 6.0 m/s, 7.0 m/s, 8.0 m/s, and 9.0 m/s. During airbag deployment with a stationary occupant, peak %C = 21.8 % while peak VC = 0.86. At 6.0 m/s impact velocity, peak %C increased to 35.1 %; at 9.0 m/s impact velocity %C = 45.0 %. Similarly, peak VC increased from 1.19 at 6.0 m/s and to 1.96 at 9.0 m/s. These results demonstrated that thoracic injury metrics %C and VC increased in dynamic testing conditions. Therefore dynamic occupant tests may be required to effectively assess OOP thoracic injury risk.
This paper deals with the interface-relevant activity of a vehicle integrated intelligent safety system (ISS) that includes an airbag deployment decision system (ADDS) and a tire pressure monitoring system (TPMS). A program is developed in LabWindows/CVI, using C for prototype implementation. The prototype is primarily concerned with the interconnection between hardware objects such as a load cell, web camera, accelerometer, TPM tire module and receiver module, DAQ card, CPU card and a touch screen. Several safety subsystems, including image processing, weight sensing and crash detection systems, are integrated, and their outputs are combined to yield intelligent decisions regarding airbag deployment. The integrated safety system also monitors tire pressure and temperature. Testing and experimentation with this ISS suggests that the system is unique, robust, intelligent, and appropriate for in-vehicle applications.
Current neck injury criteria are based on matching upper cervical spine injuries from piglet tests to airbag deployment loads and pairing kinematics from child dummies. These “child-based” scaled data together with adult human cadaver tolerances in axial loading are used to specify neck injury thresholds in axial compression and tension, and flexion and extension moment about the occipital condyles; no thresholds are specified for any other force or moment including lateral bending. The objective of this study was to develop a testing methodology and to determine the lateral bending moment injury threshold under coronal loading. Post mortem human subjects (PMHS) were used. Specimens consisted of whole body and isolated head-neck complexes with intact musculature. Intact specimen positioning included: sitting PMHS upright on a rigid seat, supporting the torso by a plate, maintaining Frankfurt plane horizontal. Isolated head-neck complexes were fixed at T1 with the occiput connected via a custom apparatus to a testing device to induce lateral bending motion. Head angular and linear accelerations and angular velocities were computed using a pyramid nine accelerometer package on the head; specimen-specific physical properties including center of gravity and moments of inertia in the three-dimensions; and equations of equilibrium. These data were used to determine neck loads at the occipital condyles. No specimens sustained injuries...
This paper presents the results from fourteen (n = 14) tests designed to evaluate the response and injury potential of a Hybrid III 3 year old dummy subject to loading by a deploying seat mounted side air bag. An instrumented Hybrid III 3 year old dummy was used for tests in two different occupant positions chosen to maximize head and neck loading. Four seat mounted thoracic side air bags were used that varied only in the level of inflator output. NHTSA’s neck injury criteria for complex loading, referred to as Nij, was modified to include moment values for both anterioposterior and lateral directions. The results of this testing indicate that side air bag loading can result in forces and moments approaching injury threshold values. While there is considerable uncertainty as to the validity of published injury criteria due to the lack of child biomechanical data, this study demonstrates the sensitivity of child response to initial position which may provide insight into placement and geometry of side airbag systems. Furthermore, the data indicates a relationship between airbag inflator properties and child dummy response for a given airbag geometry.
The pediatric cervical spine differs considerably from the adult in both its geometry and its constitutive properties. Therefore, it is susceptible to a different set of injuries, some of which are particularly severe. Recent data from the NHTSA on cervical spine injuries in low speed out-of-position airbag deployments shows that the spectrum of injuries in children is different from that of the adult. Almost all of the children (98%) sustained head or cervical spine injuries, as compared to only 38% of the adults. In addition, the injuries in children were not gender dependent, while injuries in adults occurred in females 72% of the time. The specific loads which result in these injuries are still unclear; however, examination of the biomechanical data for the adult may yield some insights. This examination also points to the need for additional biomechanical testing in order to define tolerances for pediatric cervical spine injury.
A field testing programme was developed to investigate the out-of-plane behaviour of as-built unreinforced masonry (URM) walls of four different buildings. The buildings were between approximately 80 to 130 years old, and had different masonry materials and construction forms. The objective of the testing programme was to compare the as-built wall behaviour with that studied using laboratory-based samples and to provide data with which to evaluate current seismic assessment guidelines. In total, 10 tests were performed on seven URM walls, with the out-of-plane force being uniformly applied to the wall surface. Several tests were repeated with original and modified support conditions, and the results from different tests were analysed to identify the effect of different wall boundary conditions. In particular, the effects of a concrete ring beam used at the floor levels of a URM building and the effects of wall anchorage to the building diaphragms by means of grouted steel rods were investigated. A behavioural model previously obtained through laboratory testing was proven to be effective for prediction of the cracked wall behaviour. Out-of-plane wall resistance was compared to the appropriate seismic demand of each site, and the results of the comparison were used to evaluate the NZSEE 2006 out-of-plane wall seismic evaluation method. The study showed that the evaluation method was conservative in most cases...
In order to investigate the out-of-plane behaviour of masonry infill walls, quasi-static testing was performed on a masonry infill walls built inside a reinforced concrete frame by means of an airbag system to apply the uniform out-of-plane load to each component of the infill. The main advantage of this testing setup is that the out-of-plane loading can be applied more uniformly in the walls, contrarily to point load configuration. The test was performed under displacement control by selecting the mid-point of the infill as control point. Input and output air in the airbag was controlled by using a software to apply a specific displacement in the control point of the infill wall. The effect of the distance between the reaction frame of the airbag and the masonry infill on the effective contact area was previously analysed. Four load cells were attached to the reaction frame to measure the out-of-plane force. The effective contact area of the airbag was calculated by dividing the load measured in load cells by the pressure inside the airbag. When the distance between the reaction walls and the masonry infill wall is smaller, the effective area is closer to the nominal area of the airbag.
Deformation and crack patterns of the infill confirm the formation of arching mechanism and two-way bending of the masonry infill. Until collapse of the horizontal interface between infill and upper beam in RC frame...
Seismic investigations of typical south European masonry infilled frames were performed by
testing two reduced scale specimens: one in the in-plane direction and another in the out-ofplane
direction. Information about geometry and reinforcement scheme of those structures
constructed in 1980s were obtained by . The specimen to be tested in the in-plane direction
was constructed as double leaf masonry while the specimen for testing in the out-of-plane
direction is constructed with only its exterior leaf since the recent earthquakes have
highlighted the vulnerability of the external leaf of the infills in out-of-plane direction .
The tests were performed by applying the pre-defined values of displacements in the in-plane
and out-of-plane directions in the control points. For in-plane testing it was done by hydraulic
actuator and for out-of-plane testing through the application of an airbag. Input and output air
in the airbag was controlled by using a software to apply a specific displacement in the
control point of the infill wall. Mid-point of the infill was assumed as a control point for outof-
Deformation and crack patterns of the infill confirm the formation of two-way arching
mechanism of the masonry infill until collapse of the upper horizontal interface between infill
and frame which is known as weakest interface due to difficulties in filling the mortar
between bricks of last row and upper beam. This results in the crack opening through a welldefined
path and the consequent collapse of the infill.