Development of a method for identifying the number of times to turn around during a driving for parking
Last modified: 2024-05-07
Abstract
In Japan, a super-aging society, fatal and injury accidents caused by elderly drivers have become a serious social problem. Traffic accidents caused by elderly drivers are caused partly by driving errors (e.g., misjudging the brake and accelerator pedals, reversing, missing a traffic signal, etc.) resulting from cognitive decline. As many researchers have stated, it is necessary for elderly drivers to avoid driving or return their driving licenses through appropriate evaluation of their own driving ability to continue a safe traffic society. Driving ability has been evaluated subjectively by using questionnaires or objectively by observing driving behavior. The authors have analyzed driving behavior at intersections, where driving operations are most complex.
Meanwhile, it is said that declining cognitive function can lead to the appearance of unsteady driving, lowered parking skills, and wandering driving. Therefore, in this study, we focused on parking behavior and attempted to construct a method to measure the number of vehicle turns related to parking skill. In this study, the driving data of 95 elderly people living in Hakui, Ishikawa Prefecture, who participated in the observation survey were used for analysis. Data items included time, location (latitude and longitude), 3-axis acceleration, and speed.
In analyzing parking behavior, the part of driving intended for parking was extracted from the driving data. Next, since it was difficult to determine whether the vehicle was moving forward or backward only from the acceleration information in the direction of moving, we calculated direction vectors from changes in the vehicle's position, and identified the turnaround operation by calculating the narrow angle between these direction vectors in a time-series sequence.
A threshold value must be set for the narrow angle, and in this study, trial and error was done by applying a peak detection method for time-series data. As a result, it was confirmed that it is possible to generally identify the turnaround by setting the narrow angle to about 140 degrees.
Meanwhile, it is said that declining cognitive function can lead to the appearance of unsteady driving, lowered parking skills, and wandering driving. Therefore, in this study, we focused on parking behavior and attempted to construct a method to measure the number of vehicle turns related to parking skill. In this study, the driving data of 95 elderly people living in Hakui, Ishikawa Prefecture, who participated in the observation survey were used for analysis. Data items included time, location (latitude and longitude), 3-axis acceleration, and speed.
In analyzing parking behavior, the part of driving intended for parking was extracted from the driving data. Next, since it was difficult to determine whether the vehicle was moving forward or backward only from the acceleration information in the direction of moving, we calculated direction vectors from changes in the vehicle's position, and identified the turnaround operation by calculating the narrow angle between these direction vectors in a time-series sequence.
A threshold value must be set for the narrow angle, and in this study, trial and error was done by applying a peak detection method for time-series data. As a result, it was confirmed that it is possible to generally identify the turnaround by setting the narrow angle to about 140 degrees.
Keywords
elderly drivers; parking skills; driving data