受賞区分：国内学会・会議・シンポジウム等の賞  受賞国：日本国

受賞区分：国際学会・会議・シンポジウム等の賞  受賞国：イタリア共和国

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/15389588.2024.2321915

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/15389588.2023.2278419

記述言語：英語  

DOI： 10.1016/j.aap.2022.106793

Web of Science

Scopus

PubMed

記述言語：英語   出版者・発行元：公益社団法人 自動車技術会  

Understanding car driver responses in emergency car-to-cyclist collisions is useful for developing active safety systems to reduce injuries in car-to-cyclist collisions. In this study, driver responses toward cyclists intruding into a car's path at an intersection were investigated in scenarios with different time-to-collisions (TTC) (1.5 s and 0.8 s for the near side approach, and 2.0 s for the far side approach) using a driving simulator. The drivers' responses to avoid collisions were braking and swerving, whereas swerving alone was not effective for avoiding collisions. Collisions occurred when the sum of braking reaction time (BRT) and car braking deceleration time was larger than the TTC when the cyclist was visible to drivers. The mean of BRT was 0.65 and 1.35 s in the near-side and far-side scenarios, respectively. The driver's initial gaze has an important role in affecting the driver's time to notice the cyclist. The gaze of many drivers was located on the future path (car lane) when the cyclist was visible. As the angle between the gaze direction and the cyclist was larger, the time taken for the driver to notice the cyclist was longer. As this notice time increased, the driver's response changed consistently from swerving to braking. Through this study, a collision area is proposed using TTC and car velocity based on the collision occurrence equation.

DOI： 10.20485/jsaeijae.13.2_89

Scopus

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：International Journal of Crashworthiness  

In momentum-based impact models used in accident reconstructions, the restitution coefficient is a key role to determine impulses and delta-V accurately in car-to-car collisions. The restitution coefficients can be defined as the normal and the tangential direction in the contact plane, and the same value of the normal and tangential coefficients is employed in a two-dimensional PC-Crash model. Ishikawa (1993) proposed an impact model with the normal and tangential restitution coefficient, however, to the best of the author's knowledge, few studies have further investigated tangential restitution coefficients in detail. In this study, the normal and tangential restitution coefficients of the impact model were investigated based on the finite element (FE) analysis. FE simulations of angled barrier crashes with varying barrier angles as well as 16 car-to-car collisions were conducted. As the contact plane slides, the ratio of the tangential impulse to the normal impulse becomes the same value with the maximum friction coefficient. The tangential restitution coefficient is related to whether sliding occurs on the contact plane, and can be expressed as a function of the impulse ratio. The tangential restitution coefficient decreased with increasing the impulse ratio and is positive in non-sliding collisions and negative in sliding collisions. An approximate expression for the tangential restitution coefficient was formulated as a function of the generalized impulse ratio. The calculated impulses of the impact model with normal and tangential restitution coefficients were closer to the FE analysis than the PC-Crash model which uses a constant restitution coefficient of 0.1.

DOI： 10.1080/13588265.2021.1926825

Scopus

記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

開催年月日： 2022年11月

記述言語：中国語  

開催地：Dresden, Germany   国名：ドイツ連邦共和国  

開催年月日： 2022年10月

記述言語：日本語   会議種別：ポスター発表  

開催年月日： 2020年11月

記述言語：日本語  

開催地：オンライン  

開催年月日： 2019年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Italy, Florence   国名：イタリア共和国  

開催年月日： 2019年6月

記述言語：日本語   会議種別：口頭発表（一般）