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Christina M Rudin-Brown

Publications and source records attributed to Christina M Rudin-Brown.

3 recordsLinked to original sources

The effect of driver eye height on speed choice, lane-keeping, and car-following behavior: results of two driving simulator studies.

OBJECTIVE: Two simulator studies were conducted that assessed the effect of driver eye height on speed choice, lane-keeping, and car-following behavior. The effect of eye height on the subjective variables of mental workload, frustration, and confidence was also investigated, as was the contribution of drivers' aggression. METHODS: A total of 43 participants drove a simulated route while seated at two different eye heights: one that represented the view of the road from a large SUV and one that represented the view of the road from a small sports car. Driving scenarios were comprised of both open road and car-following segments. Dependent variables included driver-selected speed, speed variability, lane position, following distance to a slower-moving lead vehicle, and the subjective variables of frustration, confidence, and mental workload. RESULTS: When viewing the road from a high eye height, drivers drove faster, with more variability, and were less able to maintain a consistent position within the lane than when viewing the road from a low eye height. Driver eye height did not influence following distance to a slower-moving lead vehicle. Driver aggression had no effect on any of the dependent variables except level of frustration. CONCLUSIONS: The two studies demonstrate that, when they are not able to reference a speedometer, drivers choose to drive faster when they view the road from an eye height that is representative of a large SUV compared to that of a small sports car. There is a need to educate drivers of SUVs and other tall vehicles of this perceptual phenomenon in order to prevent collisions that may occur in conditions where it is impossible for drivers to base their speed selection solely on posted speed limits, such as in inclement weather.

Acceleration↗

The design of child restraint system (CRS) labels and warnings affects overall CRS usability.

A study was conducted that assessed the effectiveness of different child restraint system (CRS) label/warning designs on users' installation performance. Forty-eight paid participants installed a convertible CRS in a vehicle, and two child test dummies in a CRS, using one of four label conditions. The label conditions were: (1) no labels, (2) the manufacturer's labels that were already affixed to the CRS ("Current"), (3) labels that were designed according to a combination of the current U.S. regulations concerning CRS labels and recently proposed changes to these regulations ("Proposed"), and (4) labels that were designed according to human factors principles and guidelines, and that were based on a hierarchical behavioral task analysis ("Optimal"). Results demonstrated that, overall, the Optimal labels resulted in higher usability ratings and better task performance. This indicates that labels designed using human factors and task analyses that identify critical task information requirements for label features will result in increased user compliance with instructions, higher usability, and improved task performance. Surprisingly, having no labels on the CRS resulted in better installation performance than when either the Current or the Proposed label conditions were used. This indicates that label design can decrease task performance; the actual physical design of a CRS may be just as critical as label content in the installation choices provided to the user. Collectively, results suggest that implementation of the proposed changes to the U.S. regulations concerning CRS labeling would likely not result in increased performance or usability compared to existing manufacturer labels that follow the current guidelines. In order to achieve significantly better ease-of-use and task performance, it would be necessary to implement features of the Optimal label condition.

Adult↗

Usability issues concerning child restraint system harness design.

A study was conducted to assess usability issues relating to child restraint system (CRS) harness design. Four convertible child restraint systems representing a wide variety of design features were used. Forty-two participants installed two child test dummies in both forward- and rear-facing configurations either inside or outside a test vehicle. Observer-scored checklists determined the degree to which each harness was installed correctly. Participant-scored questionnaires evaluated the 'ease-of-use' of various design features. While the percentage of correct installations exceeded 83% for all designs when installed in the forward-facing configuration, in the rear-facing position (that intended for children under 9-10 kg), there was a significant (between 65 and 89%) percentage of incorrect installations for all models. This finding is of particular interest and may be indicative of a more generalized problem with 'convertible' CRS designs when they are used in the rear-facing configuration. Furthermore, while certain design features were perceived by users as providing significantly better protection in the event of a collision, these also tended to be the features that were misused most often. The benefits and costs of various design features are discussed, and a method to test harness design usability is presented.

Adult↗