Experimental Investigation of Acceptable Latency from the Perspective of Driving Operability in Driving Simulators

Takeshi Yoshida･Takayuki Aoki･Daisuke Itagaki･Hirotaka Sakamoto･Tsubasa Oguro (Toyota Motor)

This study investigates acceptable latency thresholds in driving simulators from the standpoint of driving operability. To assess the impact of in-vehicle device communication and network latency, two types of delays—display latency and force feedback (FFB) latency—were independently evaluated. A panel-based evaluation using a physical simulator was conducted under various delay conditions. Sensory indicators related to driving operability were analyzed using a multivariate Bayesian hierarchical ordinal logistic regression model. The study established a method for evaluating perceived latency and quantified the contribution of display latency, FFB latency, and reaction force to the overall sense of delay.

A Case Study on the Reliability of Online Driving Aptitude Assessment for Older Drivers
-Study on Driver Characteristics for Delaying Driving Cessation (48)-

Shunji Taniguchi･Aiko Inoue･Hiroyuki Umegaki (Nagoya University)･Naoshi Koide (Osaka University)･Hirofumi Aoki (Nagoya University)

This study investigated the reliability of online driving aptitude assessments for older drivers. Participants completed both online assessments and university-based measurements. Items included grip strength, the Trail Making Test (TMT), the Multi-Stimulus Vision Tester (MVT), and the Hazard Perception test (HP). Online and laboratory results showed partial discrepancies for grip strength, TMT, and HP, but overall correspondence was confirmed, indicating that calibration could enhance online reliability. In contrast, MVT showed limitations in online use, requiring additional conditions. Despite these constraints, the findings suggest that online assessments remain a useful and practical tool for simplified evaluation of older drivers.

Maintaining driver alertness and suppressing the decline in thermal comfort through thermal stimulation inside the vehicle

Rina Nibe･Takuya Kurimoto･Koji Notake (Nissan Motor)･Jongseong GWAK (Takushoku University)･Akinari Hirao (Shibaura Institute of Technology)･Motoki Shino (Institute of Science Tokyo)

Maintaining driver alertness using conventional alarms often leads to reduced comfort. To examine whether thermal stimulation through air conditioning can achieve both comfort and alertness maintenance, We conducted experiments using both an actual vehicle and a driving simulator (DS) to obtain subjective evaluations and eye-closure rates. The results demonstrated that under conditions with stimulation, alertness was maintained without compromising comfort.

Development of a Controlled Testing Procedure for Evaluating Driver Alcohol Intoxication Detection Systems

Francesco Deiana･James D. Jackson･Simone Toma･Cristina Periago Linares (APPLUS+ IDIADA)

This work presents a controlled testing procedure for evaluating driver alcohol intoxication detection systems. With increasing regulatory and consumer safety pressure to address alcohol-impaired driving, there is a clear need for validated methodologies involving real human subjects. The proposed approach enables safe, standardised testing at low to moderate intoxication levels, conducted in both simulator and proving ground environments. It supports the collection of behavioural and physiological indicators necessary to assess system effectiveness. This methodology fills a critical gap between lab-based validation and real-world deployment in the development of automotive safety technologies.

A Study on Optimal Operating Force of Automotive Moving Parts Based on Muscle Activation and User Perceived Effort

Jaehoon Chung (Hyundai Motor)

This study aims to propose an ergonomic guideline for optimal operating force in automotive moving parts specifically doors and tailgates by analyzing both the user's physical load and subjective perception of discomfort. Unlike traditional design approaches , this research adopts a human-centered perspective by quantifying upper-body muscle activation using surface electromyography (EMG) and evaluating user-perceived discomfort during opening and closing operations. The results demonstrate that as operating force increases, both muscle activation and perceived discomfort rise correspondingly. Based on these findings, optimal operating force guidelines were established to satisfy two critical criteria: acceptable levels of muscle activation and minimal user discomfort. The threshold for muscle activation was determined with reference to prior ergonomic research, defining an upper limit that permits physical effort without inducing excessive fatigue.