Evaluation of driver’s mental workload by facial temperature and electrodermal activity under simulated driving conditions

The purpose of this study was to evaluate the mental workload of increasing driving speed, from 60 km/h to 180 km/h, when operating a driving simulator. The evaluation, based on changes in facial temperature and electrodermal activity, showed that the difference between nose and forehead temperature increased, that the skin potential level decreased, and that the skin conductance level increased. Monitoring facial temperature and electrodermal activity were both found to be effective in evaluating the mental workload involved.     

Haptic steering support for driving near the vehicle’s handling limits; skid-pad case

Current vehicle dynamic control systems from simple yaw control to high-end active steering support systems are designed to primarily actuate on the vehicle itself, rather than stimulate the driver to adapt his/her inputs for better vehicle control. The driver though dictates the vehicle’s motion, and centralizing him/her in the control loop is hypothesized to promote safety and driving pleasure. Exploring the above statement, the goal of this study is to develop and evaluate a haptic steering support when driving near the vehicle’s handling limits (Haptic Support Near the Limits; HSNL). The support aims to promote the driver’s perception of the vehicle’s behaviour and handling capacity (the vehicle’s internal model) by providing haptic (torque) cues on the steering wheel. The HSNL has been evaluated in (a) driving simulator tests and (b) tests with a vehicle (Opel Astra G/B) equipped with a variable steering feedback torque system. Drivers attempted to achieve maximum velocity while trying to retain control in a circular skid-pad. In the simulator (a) 25 subjects drove a vehicle model parameterised as the Astra on a dry skid-pad while in (b) 17 subjects drove the real Astra on a wet skid-pad. Both the driving simulator and the real vehicle tests led to the conclusion that the HSNL assisted subjects to drive closer to the designated path while achieving effectively the same speed. With the HSNL the drivers operated the tires in smaller slip angles and hence avoided saturation of the front wheels’ lateral forces and excessive understeer. Finally, the HSNL reduced their mental and physical demand.     

Tuning and objective performance evaluation of a driving simulator to investigate tyre behaviour in on-centre handling manoeuvres

Driving simulation aims at reproducing, within a safe and controlled environment, sensorial stimuli as close to those perceived during the actual drive as possible, in order to induce driving behaviour similar to the real one. This paper illustrates an activity carried out on the driving simulator Virtual Environment for Road Safety, bound for system performance optimisation while dealing with subjective and objective tyres evaluation in the field of on-centre manoeuvres. Such activity can be divided into two main steps. The first one, described herewith, has been focusing on platform motion algorithms tuning and has led to driving simulator objective validation within the on-centre range. Device capability of reproducing dynamics, worked out by the vehicle model, has been thoroughly examined. Simulator sensitivity to a few tyre parameters influencing vehicle lateral dynamics has been analysed too. The second step – calling for the support of experienced drivers – will pursue subjective validation.     

Study of driver characteristics using driving simulator considerations on difference in accident avoidance performance due to age

Many studies have been done recently to clarify the driving capability of elderly drivers. Elderly drivers are suffering from mental and physical deterioration, but also have appropriate judgement supported by their long driving experience. This study observed the effects of these characteristics when facing an accident, using a driving simulator.     

Study of in-vehicle route guidance systems for improvement of right-side drivers in the Japanese traffic system

A country can adopt one of two standards for traffic flow — cars may travel on the left or right side of the road. When drivers who are accustomed to driving on the right side of the road drive on the left side, and vice versa, the mental workload is likely increased due to the driver’s unfamiliarity with a new language, the position of the driver’s seat, different driving directions, and other factors that differ from those of their home country. One method of doing this is to make sure that the in-vehicle route guidance information (RGI) is not overly complicated — thereby assisting drivers in improving their safety. Consequently, the aim of this study was to facilitate mobility and improve safety for natural right-side drivers driving temporarily in left-side traffic. In this study, driver behavior and workload — given various types of RGI — were evaluated in a driving simulator with a variety of prescribable test conditions. This research was composed of two experiments. In the first, various types of in-vehicle route guidance systems were tested and evaluated in terms of their characteristics and associated driver behaviors (while driving). In the second experiment, systemic factors and effectiveness were evaluated by two combined systems, arrow and map-type information, based on the results of the first experiment. In light of both experiments, the various types of route guidance systems were discussed in terms of their results. A navigation system was proposed to alleviate some of the secondary tasks such as route selection.     

Vehicle dynamics testing in motion based driving simulators

ABSTRACT

This article investigates the potential of a motion-based driving simulator in the field of vehicle dynamics testing, specifically for heavy vehicles. For this purpose, a case study was prepared embodying the nature of a truck dynamics test setup. The goal was to investigate if the drivers in the simulator could identify the handling differences owed to changes in vehicle parameters, while driving the simulated trucks. Results show that the drivers could clearly identify the differences in vehicle behaviour for most of the performed tests, which motivates further investigative work in this area and exposes the feasibility of heavy vehicle dynamics testing in simulators.     

汽车驾驶模拟器在交通安全中的应用综述

汽车驾驶模拟器是1种研究“人‐车‐路‐环境”交通特性的重要工具,由于具有重现性好、安全性高、成本低等优势,被广泛应用于交通研究方面,尤其因其能够在危险场景中采集多种车辆数据,近年来汽车驾驶模拟器在交通安全方面的研究进展飞速。文中简要介绍了汽车驾驶模拟器的国内外发展历史,从驾驶分心、道路设计、交通设计、交通事故和驾驶疲劳5个方面梳理出汽车驾驶模拟器在交通安全领域的应用研究,并分析了这5个方面研究领域中驾驶模拟器实验的其中利弊,探讨了汽车驾驶模拟器在中国交通安全研究中的应用前景及存在的问题。      

汽车操纵稳定性的主观评价

本文介绍了汽车操纵稳定性的主观评价方法，探讨了影响主观评价的因素。利用吉林工业大学的开发型车辆驾驶模拟器进行了汽车稳定性的主观评价试验，采用一对一即时比较法实现了１４个车辆方案易操纵性的驾驶员主观评价排序，并进行了操纵稳定性定量评价指标与主观评价的相关分析。     

具有模块化结构的汽车动力学仿真模型的初步研究

初步探讨了面向开发型驾驶模拟器的具有模块化结构的汽车动力学仿真模型建立方法，从而可以在此基础上进一步建立一套通用的面向结构的汽车动力学仿真程序，便捷地在开发型驾驶模拟器上实现对不同类型或同类型不同结构车辆性能的仿真。     

Application of a driving simulator to the development of in-vehicle human-machine-interfaces

The use of a driving simulator in the development of human-machine-interfaces (HMI) such as a navigation, information or entertainment system is discussed. Such use addresses the need to study and evaluate the characteristics of a candidate HMI early in the R&D and design stage to ensure that it is likely to meet various objectives and requirements, and to revise the HMI as may be necessary. Those HMI requirements include such things as usability, driver comfort, and an acceptable level of attentional demand in dual task conditions (driving while using an HMI). Typically, such an HMI involves an information display to the driver, and a means for driver input to the HMI. Corresponding simulator requirements are discussed, along with typical simulator features and components. The latter include a cab, control feel systems, visual image generator, real time scenario control (task definitions), a motion system (if provided), and data acquisition. Both fixed and moving base systems are described, together with associated benefits and tradeoffs. Considerations in the design of the evaluation experiment are discussed, including definition of primary and secondary tasks, and number of driver subjects (experimental participants). Possible response and performance measures for the primary and secondary tasks are noted, together with subjective measures such as task difficulty and ease of using the HMI. The advantages of using a driving simulator to support R&D are summarized. Some typical and example simulator uses are noted.     

驾驶模拟器在自动驾驶系统中的应用研究

自动驾驶车辆在实际道路上行驶之前的测试阶段是一个至关重要的环节。一个低成本、高效率以及高精度测量的自动驾驶车辆的测试方式,对于自动驾驶车辆的开发具有重要意义。将驾驶模拟器运用到研究自动驾驶车辆测试已是近年来的一个研究热点。基于虚拟驾驶场景的自动驾驶车辆的检测,通过组合虚拟驾驶场景的背景车辆、行人、交通灯、建筑、指示标牌等元素,研究将驾驶模拟器与虚拟驾驶场景的联合应用来测试自动驾驶车辆。设计了典型的交通场景,通过自动驾驶车辆和背景车辆的实时交互,研究自动驾驶车辆的各项性能指标。研究结果表明:该驾驶模拟器可以高度拟合人类驾驶体验,驾驶员通过驾驶模拟器控制背景车辆能够很好的模拟现实中的驾驶行为,对自动驾驶车辆的仿真测试起到了促进作用。     

Vehicle sensor data-based analysis on the driving style differences between operating indoor simulator and on-road instrumented vehicle

Abstract

Indoor simulator and on-road instrumented vehicle are the most popular ways to analyze driving behaviors by using collected Vehicle Sensor Data (VSD). However, for a same driver, the driving performance could be different in the real world and in the simulated world. Even though many studies have been conducted to discover the differences of driving behaviors in these two circumstances, little research has focused on analyzing the differences in driving style, which can provide more integrated knowledge of a driver from the natural structure, stimulus–response mechanism, of driving behaviors. Therefore, in this paper, the driving styles in both the real world and the simulated world are extracted by implementing the nonnegative matrix factorization method on the collected VSD data. Through this analysis, the driving style differences can be quantitatively described and discussed in detail. It is found that the drivers tend to be more unstable and sometimes aggressive when driving the simulator and the deviation in the perception of temporal gap in two circumstances is also discovered. The research findings are particularly valuable to calibrate the driving simulator and construct more reliable driving behavior models.     

基于弯道车速检验的驾驶模拟系统证实研究

通过在弯道上的模拟驾驶和实地实验对比分析,对驾驶模拟系统的运动逼真性进行评价。在建立了与实验路段和场地同等条件的三维虚拟场景后,由10名受试者进行对比实验。结果表明,场地实验结果与模拟驾驶实验结果基本吻合;利用t检验对实验数据进行假设检验,表明在虚拟实验条件下所得数据与真实实验数据无显著性差异,从而验证了模拟系统实验数据的可靠性。     

研究型汽车驾驶模拟器有效性确认研究

随着研究型汽车驾驶模拟器的应用越来越广泛,其有效性研究也逐渐被人们关注起来,如何确认一台模拟器的有效性成为了现今模拟器研究的一项课题,从分析以往驾驶模拟器有效性研究的文献入手,总结了研究者们采用的方法,分析了其中利弊,提出了一套有效性确认研究所应具备的方法,并附有算例。     

驾驶人安全意识提升方法与实现

研究表明,缺少安全驾驶意识的驾驶人在行车过程中易发生交通事故,并逐渐成为导致交通事故的主要原因之一。文中首先对安全驾驶意识的内涵进行了描述,并根据内容的不同进行了分类。举例介绍了基于动画和视频形式的安全意识提升方法的设计过程,具体实现流程以及实现效果;提出了基于汽车驾驶模拟平台的安全意识提升技术,将危险交通情景分为纵向和横向两大类,分别举例介绍了具体的实现过程和触发条件算法。     

Safety benefits of integrated pedestrian protection systems

This study developed a methodology for evaluating the effectiveness of an integrated pedestrian protection system (IPPS) based on simulations. The proposed IPPS consists of active and passive vehicular systems for protecting pedestrians, including a pedestrian warning information system (PWIS), an active hood lift system (AHLS), and pedestrian airbag system (PAS). Two simulation methods were applied in the proposed methodology: a driving simulation and a finite element simulation. A driving simulator was used to obtain the change in collision speed, which is a key parameter for evaluating driving behavior when a PWIS is applied. In addition, a well-known simulator for finite element analysis, LSDYNA was used to simulate the impact of a pedestrian on a vehicle hood in a pedestrian-vehicle collision. The head injury criterion (HIC), which is an outcome of LS-DYNA simulations, is a major parameter for evaluating passive safety systems. The probability of pedestrian fatalities by collision speeds and HICs were estimated to quantify the safety benefits of an IPPS based on the statistical analyses. The results showed that an IPPS is capable of reducing pedestrian fatalities by approximately 90 % associated with jaywalking in the midblock and walking on the roadside. The findings of this study can be used to boost the development of various vehicular technologies for pedestrians. The results can be effectively used for policy making and deriving legislative requirements associated with advanced vehicular technologies for enhancing pedestrian safety.     

山区公路爬坡车道的交通特性及驾驶安全性模拟评价

以山区公路上设置的某一爬坡车道为试验对象,利用驾驶模拟试验对其交通特性及驾驶安全性进行仿真。根据设计图和现场环境构建了三维虚拟试验场景,通过VISSIM生成试验路段交通流;32名受试者在4种交通条件下进行了驾驶模拟试验;模拟过程中记录车辆的速度、轨迹、加速度、制动力等数据;通过VISSIM仿真试验确定了该爬坡车道的交通量阈值。分析结果表明,在常规交通流情况下,该爬坡车道可提高主路上的车速及其平稳性,同时可减少来自对向车道的冲突;但随着交通流量趋于饱和,其有效性逐渐减弱甚至产生负面影响。     

Les facteurs d’accidents de la route par somnolence chez les conducteurs âgés: Prévention par l’activité physique

Sleepiness while driving is a frequent factor in car crashes and the primary cause of fatal accidents on French motorways, particularly among the elderly. The ageing process is accompanied by chronobiological disturbances which affect diurnal vigilance in particular and may have an impact on driving. The quality of nocturnal sleep diminishes among the elderly and sleep takes the form of a number of short, increasingly frequent naps during the day. All the changes in nocturnal sleep are accompanied by changes in circadian rhythms, the most striking of which is a reduction in amplitude. To counteract the effects of ageing, we have investigated the extent to which regular moderate physical activity can have a beneficial effect on circadian rhythms and the quality of sleep. Our study shows that such activity results in a subjective and objective improvement in the quality of sleep and restores circadian rhythms. There is also an improvement in driving performance on a simulator.     

In-vehicle display HMI safety evaluation using a driving simulator

Recently, telematics services and in-vehicle display devices such as the CNS (Car Navigation System) have become new causes of traffic accidents. These accidents are caused by ‘Inattention’ from the increase of the driver’s mental workload while he/she is driving. The driver of a vehicle (except for emergency or police vehicles) must not use a hand-held mobile phone while the vehicle is moving. To address this problem, Australia, England, Italy, Brazil and some states in the US have banned the use of hand-held mobile devices during driving. However, there are no restrictions on the use of in-vehicle displays or on the display’s positions. The position of a navigation system in a vehicle should be assessed objectively, and the effect of the position on the driver’s attention should be studied. Some existing research reports that in-vehicle distraction not only leads to reduced speeds and more frequent lane switching, but also more gazing by the driver to the centre of the road. In this study, to develop an assessment method and to propose the proper position of a CNS, an experiment is carried out in a driving simulator environment. Different methods to track the gaze and physical parameters of the driver are used for HMI (Human-Machine Interface) assessment. The experiment is carried out in a driving simulator to observe the glancing distribution during driving according to the position of the navigation system. Fourteen subjects participated in this experiment. Changes in subjects’ physiological signals and glancing distribution rates were collected.     

Slope Shift Strategy for Automatic Transmission Vehicles Based on the Road Gradient

Motivated by the development of high-precision digital maps for advanced driver assistance system (ADAS) in recent years, this study provides a new approach to solve the problems of the conventional automatic transmission vehicle travelling on sloping roads. Based on vehicle dynamics, shift problems on hilly roads are analyzed. A novel intelligent shift strategy is proposed, which consists of a dynamic shift schedule for the uphill, a safety shift schedule for the downhill, and a comprehensive economical shift schedule for the gentle slopes. A set of driver-in-loop co-simulation tests was conducted in a driving simulator that is equipped with a MATLAB/Simulink dynamics simulation platform. The test results verified the effectiveness of the new intelligent shift strategy. With the road information provided by a high-precision digital map, busy shifting can be eliminated, and improved dynamic performance can be achieved for a vehicle travelling on the uphill roads; undesired upshift can be prevented, and engine traction resistance can be used to relieve the load of braking system when a vehicle travelling on the downhill roads; also, fuel consumption can be reduced for a vehicle travelling on a gently sloped road. Consequently, this novel intelligent shift strategy offers a reliable and effective solution for improving a vehicle’s driving performance on a hilly road.