Abstract
We have developed a bench test method to assess driver distraction caused by the load of using infotainment systems. In a previous study, we found that this method can be used to assess the task loads of both visual-manual tasks and auditory-vocal tasks. The task loads are assessed using the performances of both pedal tracking task (PT) and detection response task (DRT) while performing secondary tasks. We can perform this method using simple equipment such as game pedals and a PC. The aim of this study is to verify the reproducibility of the PT-DRT. Experiments were conducted in three test environments in which test regions, experimenters and participants differed from each other in the US, and the test procedures were almost the same. We set two types of visual-manual tasks and two types of auditory-vocal tasks as secondary tasks and set two difficulties for each task type to vary the level of task load. As a result of these experiments, we found that differences in performances of PT and DRT among the different task types and the difficulties of the secondary tasks were similar across all the environments. This result suggests that the PT-DRT has a good reproducibility of relative assessments among various tasks, independent of test regions and experimenters. Owing to the good reproducibility and the ease of use, the PT-DRT could become a standard test method for various developers and researchers to fairly assess various tasks in various regions.