Biomedical subjects

Brian N Fildes

Publications and source records attributed to Brian N Fildes.

6 recordsLinked to original sources

PubMed2006

Worldsid assessment of far side impact countermeasures.

Far side impact trauma has been demonstrated as a significant portion of the total trauma in side impacts. The objective of the study was to assess the potential usefulness of countermeasures and assess the trade-offs associated with generic countermeasure design. Because the WorldSID dummy has demonstrated promise as a potential far side impact dummy, it was chosen to assess countermeasures in this mode. A unique far side impact buck was designed for a sled test system that included, as a standard configuration, a center console and outboard three-point belt system. This configuration assumed a left side driver with a right side impact. The buck allowed for additional options of generic restraints including shoulder or thorax plates or an inboard shoulder belt. The entire buck could be mounted on the sled in either a 90-degree (3-o'clock PDOF) or a 60-degree (2-o'clock PDOF) orientation. A total of 19 WorldSID tests were completed. The inboard shoulder belt configuration produced high shear forces in the lower neck (2430 N) when the belt position was placed over the mid portion of the neck. Shear forces were reduced and of opposite sign when the inboard belt position was horizontal and over the shoulder; forces were similar to the standard outboard belt configuration (830 - 1100 N). A shoulder or thorax restraint was effective in limiting the head excursion, but each caused significant displacement at the corresponding region on the dummy. A shoulder restraint resulted in shoulder displacements of 30 - 43 mm. A thorax restraint caused thorax deflections of 39 - 64 mm. Inboard restraints for far side impacts can be effective in reducing head excursion but the specific design and placement of these restraints determine their overall injury mitigating characteristics.

Accidents, Traffic↗

PubMed2005

Crossing roads safely: an experimental study of age differences in gap selection by pedestrians.

The over-representation of older pedestrians in serious injury and fatal crashes compared to younger adults may be due, in part, to age-related diminished ability to select gaps in oncoming traffic for safe road-crossing. Two experiments are described that examine age differences in gap selection decisions in a simulated road-crossing environment. Three groups of participants were tested, younger (30-45 years), young-old (60-69 years) and old-old (>75 years). The results showed that, for all age groups, gap selection was primarily based on vehicle distance and less so on time-of-arrival. Despite the apparent ability to process the distance and speed of oncoming traffic when given enough time to do so, many of the old-old adults appeared to select insufficiently large gaps. These results are discussed in terms of age-related physical, perceptual and cognitive limitations and the ability to compensate for these limitations. Practical implications for road safety countermeasures are also highlighted, particularly the provision of safe road environments and development of behavioural and training packages.

Accidents, Traffic↗

PubMed2005

Crash risk of older female drivers--contributing factors.

Using data from i) a self-administered survey of 673 older female drivers, and ii) a case-control study of 48 crash-involved and 44 non crash-involved older female drivers, some factors that may predict crash involvement were identified. Survey data gathered self-reported information on demographic characteristics, health status, travel patterns and driving practices. A battery of functional performance assessments were administered by trained experimenters in the case-control study, and participants completed a second detailed self-administered questionnaire. Factors found to predict crash involvement included driving characteristics such as being the main driver in the household, not highly confident of being a safe driver, experiencing difficulty driving in unfamiliar areas and having problems with the driving style of other drivers. In addition, low attentional, cognitive and motor skills and presence of multiple medical conditions were significant predictors of crash involvement.

Accidents, Traffic↗

PubMed2004

Perceptual lane width, wide perceptual road centre markings and driving speeds.

The possibility that driving speeds could be reduced through the use of lane delineation was explored. Using a high-fidelity driving simulator, 28 experienced drivers were measured on seven two-lane rural roads with lane widths of 3.6, 3.0, or 2.5 m, and with either a standard centreline (control), a wide painted hatched road centre marking, or a wide white gravel road centre marking. Driving speeds were reduced on the narrowest lane width road, and further reduced on straight road sections that contained the centre marking with painted hatching. It was concluded that the narrow lane width increased steering workload and reduced speeds through a speed-steering workload trade-off, whilst the hatched road centre marking enhanced peripheral visual speed perception, leading to higher speed estimations and slower speeds. Therefore, narrowing the lane width below 3.0 m by using a painted hatched road centre marking should be an effective way to reduce driving speeds.

Acceleration↗

PubMed2002

Driving simulator validation for speed research.

The behavioral validation of an advanced driving simulator for its use in evaluating speeding countermeasures was performed for mean speed. Using mature drivers, 24 participants drove an instrumented car and 20 participants drove the simulator in two separate experiments. Participants drove on roads which contained transverse rumble strips at three sites, as well as three equivalent control sites. The three pairs of sites involved deceleration, and were the approaches to stop sign intersections, right curves, and left curves. Numerical correspondence (absolute validity), relative correspondence (or validity), and interactive (or dynamic) relative validity were analyzed, the latter using correlations developed from canonical correlation. Participants reacted to the rumble strips, in relation to their deceleration pattern on the control road, in very similar ways in both the instrumented car and simulator experiments, establishing the relative validities. However, participants generally drove faster in the instrumented car than the simulator, resulting in absolute validity not being established.

Adult↗

PubMed2002

Observations of seating position of front seat occupants relative to the side of the vehicle.

This study was an on-road observational study of the seating position and limb position of front seat occupants relevant to the side of the car for a representative sample of occupants during straight road driving and turning manoeuvres. A video camera captured over 650 front-on images of passenger car occupants in Metropolitan Melbourne. Results showed a significant numbers of occupants were seated out-of-position while travelling on the road and that a number of these were seated in a manner that may possibly result in injury from the deployment of a side airbag. This was particularly so while turning, a situation common in many side impacts. A substantial number of front seat occupants' arms were exposed to severe injury in the event of a side impact crash. These findings highlight a number of aspects of seating behaviour of driver and front passengers that need to be taken into account when designing side impact airbags.

Adult↗