Effectiveness of replacement of automotive side mirrors by in-vehicle LCD-Effect of location and size of LCD on safety and efficiency-

The World Forum for Harmonization of Vehicle Regulations (WP29) announced their policy to admit the replacement of side mirrors by cameras and LCD monitors. It is expected that the replacement enhances the fuel efficiency of automotives, and such a policy should be welcome in a sense. However, at present, few data on the safety and the efficiency of the replacement system are reported. The aim of this study was to examine whether the replacement of side mirrors by LCDs is effective from the viewpoints of the safety and the efficiency. The participants were required to simultaneously carry out a main simulated driving task and a secondary discrimination task of a pre-specified vehicle displayed on a side mirror or in-vehicle LCD. The safety and the efficiency evaluation measures were: tracking error in a simulated driving task, the percentage of overlook and false recognition of a target vehicle, the state of looking aside judged by the horizontal neck movement, the distance between own and the proceeding vehicles, the time until the appearance of the pre-specified vehicle on the side mirror or LCD to its discrimination and reaction, and the subjective rating on visibility. The experimental factors were the size (6-inch or 8-inch) and placement location of display (side mirror, around the center of driver, around a steering wheel, and around a side mirror), and the side of a driver (left or right). As a result of comparing the safety and efficiency measures between the side mirror and the replacement system, LCD was found to be more effective from the viewpoint of the reaction time to the pre-specified vehicle and the subjective rating on visibility.