Josef Krems

Chemnitz University of Technology · Department of Psychology

Due to demographic change, it is currently becoming apparent that the already inadequate public transport services in rural areas such as the Ore Mountains region (Rehme et al., 2023) could deteriorate further. The introduction of highly automated shuttle buses (HASBs) is therefore a promising approach to ensure access to mobility, especially for o...

In a driving simulator study, six experts interacted with an in-vehicle voice assistant (VA) and rated different latencies. The results suggest that in order to maintain drivers’ satisfaction with the interaction, in-vehicle VAs should have a latency of no more than 5 s. A slight delay of 1.5 s was rated best while shorter latencies caused highest...

Automated driving is continuously evolving and will be integrated more and more into urban traffic in the future. Since urban traffic is characterized by a high number of space-sharing conflicts, the issue of an appropriate interaction with other road users, especially with pedestrians and cyclists, becomes increasingly important. This chapter prov...

The design of automotive human–machine interfaces (HMIs) for global consumers’ needs to cater to a broad spectrum of drivers. This paper comprises benchmark studies and explores how users from international markets—Germany, China, and the United States—engage with the same automotive HMI. In real driving scenarios, N = 301 participants (premium veh...

The driving style of an automated vehicle (AV) needs to be comfortable to encourage the broad acceptance and use of this newly emerging transport mode. However, current research provides limited knowledge about what influences comfort, how this concept is described, and how it is measured. This knowledge is especially lacking when comfort is linked...

Offering the opportunity to comfortably carry heavy load, e-cargo bikes are an environmentally friendly alternative to motor vehicles. Especially in urban areas, where e-cargo bikes contribute to resolve challenges like noise pollution and limited space, there is an increasing number of sharing-systems that offer users the option of renting powerfu...

As the availability of electricity from renewable sources in the power grid can fluctuate greatly, smart charging of battery electric vehicles (BEVs) is an effective approach to balance the grid. However, user centred smart BEV charging requires detailed settings of the BEV drivers’ mobility and consumption needs as well as the collection and proce...

Currently, the driving behavior of highly automated shuttles (SAE Level 4) is characterized by travel speeds below 20 km/h and frequent unexpected stops for rearward traffic. This may lead to congestion, frustrations of following road users, and risky overtaking maneuvers. Since this driving behavior is rather unfamiliar to human road users, transp...

Actions in the real world have immediate sensory consequences. Mimicking these in digital environments is within reach, but technical constraints usually impose a certain latency (delay) between user actions and system responses. It is important to assess the impact of this latency on the users, ideally with measurement techniques that do not inter...

The present contribution deals with a practical insight into the design, implementation, and evaluation of different participation formats (on-site, direct mail, online) to participate in a living lab. A total sample of 290 citizens was recruited to promote sustainable mobility (i.e. walking and cycling) and improve urban space quality. Results fur...

Automated vehicles (AVs) are required to interact predictably and intuitively with conventional road users to support traffic safety and efficiency. This might be achieved by implementing established interaction capabilities of manual drivers in AVs. When coordinating interactions, drivers anticipate the development of driving scenes and adapt own...

Actions in the real world have immediate sensory consequences. Mimicking these in digital environments is within reach, but technical constraints usually impose a certain latency (delay) between user actions and system responses. It is important to assess the impact of this latency on the users, ideally with measurement techniques that do not inter...

Similar to battery electric vehicles (BEVs), the range of motorised bicycles (i.e. pedelecs) is limited. Although conventional cycling is always a fallback-option, running out of charge is an adverse event for users due to the high weight of pedelecs. For BEVs, eco-driving (i.e. applying an energy-efficient driving style) has been found to be helpf...

The Box Task combined with a Detection Response Task (BT + DRT) is a relatively new and easy-to-use method to assess in-vehicle system demand, consisting of a visual-manual task (BT) and a cognitive task (tactile DRT). Currently, little is known regarding the sensitivity of the BT + DRT for different types and difficulty levels of secondary tasks....

Automated driving needs to be comfortable to encourage the broad acceptance and usage of automated vehicles (AVs). However, current research provides limited knowledge on the descriptions and influencing factors of user comfort in automated driving, especially from the perspective of an AV’s driving styles. This paper presents results from an onlin...

As a social system, traffic requires the coordination between different involved road users, particularly in shared spaces (e.g., parking areas) with fewer statutory regulations and hence more ambiguous encounters. By anticipating the development of driving scenes and adapting own driving actions, drivers maintain individually varying safety margin...

While autonomously parking e-cargo bikes offer the potential to enhance users’ comfort and time efficiency at sharing-stations, it is important to ensure a safe and useable interaction. External human machine interfaces (eHMIs) provide a possible solution for highly automated systems to communicate relevant information and to ensure system transpar...

In this work, an implementation of a virtual reality (VR) cycling simulation is presented and it is aimed to investigate the perceived criticality in traffic conflict scenarios as well as the participants’ experience of presence within the VR cycling simulation.

Wearable devices are increasingly used for assessing physiological data. Industry 4.0 aims to achieve the real-time assessment of the workers’ condition to adapt processes including the current mental workload. Mental workload can be assessed via physiological data. This paper researches the potential of wearable devices for mental workload assessm...

There are several standardized test methods to assess the distraction potential of secondary task engagement while driving. One relatively new method is the Box Task combined with a Detection Response Task (BT + DRT). This method has the potential to distinguish between different dimensions of driver distraction. While the DRT is being implemented...

The Box Task (BT) combined with a Detection Response Task (DRT) is a method to assess different dimensions of secondary task demand caused by portable (electronic) devices or in-vehicle systems. This paper presents a comprehensive analysis of the DRT using an evidence accumulation model. The aim was to replicate influences of cognitive load on the...

To facilitate the usage and expected benefits of higher-level automated vehicles, passengers' distrust and safety concerns should be reduced through increasing system transparency (ST) by providing driving-related information. We therefore examined the effects of ST on passengers' gaze behavior during driving, trust in automated driving and evaluat...

In recent years, more and more cities have been aiming to banish motorized traffic from their city centers to reduce transport related CO2 emissions, create space and decrease noise. Micromobility solutions, such as (e-)bike sharing systems, have the great potential to mitigate car use while ensuring mobility in cities. However, the transportation...

Abductive reasoning is the process of finding the best explanation for a set of observations. As the number of possible observations and corresponding explanations may be very high, it is commonly accepted that working memory capacity is closely related to successful abductive reasoning. How- ever, the precise relationship between abductive reasoni...

Automated vehicles (AVs) need to interact in an expected manner with manual road users to ensure traffic safety and user acceptance. Therefore, established interaction patterns of manual traffic participants should be implemented in AVs. In manual driving, accepted time gaps (gap acceptance, GA) frequently coordinate interactions between different...

Cycling offers the opportunity to reach destinations in a healthy and eco-friendly manner. However, cyclists are specifically vulnerable traffic participants facing potential hazards with possibly severe injuries. To support cyclists and enhance cycling safety, we developed and evaluated a cyclist warning system (CWS) using a combination of visual,...

Cycling offers the opportunity to reach destinations in a healthy and eco-friendly manner. However, cyclists are specifically vulnerable traffic participants facing potential hazards with possibly severe injuries. To support cyclists and enhance cycling safety, we developed and evaluated a cyclist warning system (CWS) using a combination of visual,...

To ensure traffic flow and road safety in automated driving, external human–machine interfaces (eHMIs) could prospectively support the interaction between automated vehicles (AVs; SAE Level 3 or higher) and pedestrians if implicit communication is insufficient. Particularly elderly pedestrians (≥65 years) who are notably vulnerable in terms of traf...

A comparison of two Trust in Automation Scales: uni dimensional Trust in Automation Scale by Jian et al. (2000) vs. multi faceted Trust in Automation Scale by Körber et al. (2019).

Bidirectional charging management could offer benefits to individuals, society and energy providers by using the batteries of Battery Electric Vehicles (BEVs) as a means of storage. To successfully design and implement this technology, it is necessary to match customer mobility needs with the goals of the energy sector. Therefore, practice and rese...

External human-machine interfaces (eHMIs) could enhance the interaction between automated vehicles and surrounding traffic participants if implicit signals are insufficient. Traffic safety requires an appropriate level of trust considering potential eHMI failures. Thus, the current study investigated effects of eHMI system failures on elderly parti...

Driving automation systems have already entered the commercial market and further advancements will be introduced in the near future. Level 3 automated driving systems are expected to increase safety, comfort and traffic efficiency. For the human driver, these functions and according human-machine interfaces are a novel technology. In the human fac...

The vision of automated driving becomes more and more concrete and vehicles that drive autonomously—under the supervision of the human driver—are already on the roads. It might not take much longer and vehicle automation will be available with which drivers are allowed to divert their attention away from the driving task to non-driving related acti...

Face tracking as innovative and unobtrusive sensor technology offers new possibilities for driver state monitoring regarding discomfort in automated driving. To explore the potential of automated facial expression analysis, video data of two driving simulator studies were analyzed using the Visage facial features and analysis software. A gender-bal...

To support road safety and user acceptance, the interaction capabilities of automated vehicles (AVs) need to be intuitive and transparent. Therefore, established interaction capabilities of manual drivers need to be implemented in AVs. In manual driving, accepted time gaps (gap acceptance, GA) are frequently applied to coordinate interactions betwe...

The assessment of task demand caused by in-vehicle systems is crucial to avoid distraction while driving. The Box Task (BT) in combination with a tactile Detection Response Task (DRT) provides a method for measuring both visual-manual and cognitive secondary task demand. In the present study, the impact of cognitive, auditory-verbal tasks on the BT...

Aim of this research was to better understand the impact of urban infrastructure design on people’s perceived environmental quality, perceived safety and the motivation for active mobility within the city. The requirements for walking and cycling infrastructure were first generated in face-to-face interviews (N = 82). Then, in a within-subject desi...

As vulnerable road users, cyclists have an increased risk of sustaining severe injuries when involved in an accident. Often, obstructed views and a lack of attention account for accidents or safety critical events (SCE) including cyclists. In turn, negative cycling experiences and/ or a poor sense of security when participating in road traffic may...

Abductive reasoning describes the process of deriving an explanation from given observations. The theory of abductive reasoning (TAR; Johnson and Krems, Cognitive Science 25:903–939, 2001) assumes that when information is presented sequentially, new information is integrated into a mental representation, a situation model, the central data structur...

Experts assume that the dark-number of non-registered less severe cyclists’ incidents that do not result in hospitalisations such as near misses or safety critical events (SCE) is vastly greater than the number of registered accidents. There are only few studies, which make estimates on the extent of this so-called underreporting. To our knowledge,...

One of the key questions arising in the context of automation of our traffic system is: Which strategies will be implemented for the communication between automated vehicles (AVs) and other traffic participants, such as pedestrians? In this context, the current study examines light-based communication signals as one possible solution for designing...

To ensure safety and support drivers' comfort and acceptance, automated vehicles (AVs) need to communicate with other traffic participants. Hence, a user-centred implementation of manual driving behaviour is considered as beneficial in AVs. Currently, manual driving is often coordinated by informal communication. Thus, specific parameters regarding...

In-vehicle information systems allow drivers to engage in secondary tasks, such as selecting music via the infotainment system, while driving. However, interacting with such systems can lead to visual, manual as well as cognitive distraction. Assessing in-vehicle system demand while driving is, therefore, a central topic in driver distraction resea...

Lastenpedelecs bieten eine große Chance für einen Wandel hin zu einer aktiveren und nachhaltigeren Mobilität - nicht zuletzt wegen ihres großen Potenzials, das Auto als Verkehrsmittel für bestimmte Wege zu ersetzen. Für eine verstärkte Nutzung dieses Transportmittels sind neben geeigneten Bereitstellungskonzepten auch Faktoren wie Nutzerfreundlichk...

To exploit the benefits of automated vehicles (AVs), the systems’ functions need to be accepted by the driver and other traffic participants. Thus, the human-machine interaction should be considered as a key issue. Manual driving is often coordinated by implicit communication cues. Therefore, specific parameters such as drivers’ gap acceptance (GA)...

Automated vehicles promise transformational benefits for future mobility systems, but only if they will be used regularly. However, due to the associated loss of control and fundamental change of in-vehicle user experience (shifting from active driver to passive passenger experience), many humans have reservations towards driving automation, which...

Lane changes (LCs) are highly complex, therefore the announcement and anticipation at an early stage of these maneuvers is important for traffic safety. Since manual drivers mainly apply implicit driving cues, automated vehicles (AVs) need to be able to detect and apply these cues to enhance the acceptance of AVs and therefore exploit the benefits...

Abductive reasoning is the process of finding the best explanation for a set of observations. As the number of possible observations and corresponding explanations may be very high, it is commonly accepted that the capacity of working memory is closely related to successful abductive reasoning. However, the precise relationship between reasoning an...

Abductive reasoning describes the process of deriving an explanation from given observations. The Theory of Abductive Reasoning (TAR; Johnson & Krems, 2001) assumes that when information is presented sequentially, new information is integrated into a mental representation, a situation model, the central data structure on which all reasoning process...

Automated driving is an ever-fast developing technology which is going to change the traffic system fundamentally. This development raises the question about how to interact in urban, less-regulated situations involving automated vehicles (AV) and vulnerable road users (VRU) like cyclists and/or pedestrians. Thus, it is essential to gain an underst...

Electromobility refers to the usage of vehicles that are propelled by electric engines. The term includes different kinds of vehicles (cars, pedelecs, e-bikes, e-scooters, buses, rail-bound trams, or trains) and infrastructure necessary for charging as well as the management of the system. It also includes organizational issues to support travel ne...

Automated driving research over the past decades has mostly focused on highway environments. Recent technological developments have drawn researchers and manufacturers to look ahead at introducing automated driving in cities. The current position paper examines this challenge from the viewpoint of scientific experts. Sixteen Human Factors researche...

With highly automated vehicles (HAVs), the human role shifts from active driver to mostly passive passenger, which has an impact on the perceived comfort while being driven. A number of factors need to be taken into account when designing an automated driving style (ADS) with the aim to minimize human discomfort. In this paper, the authors build on...

The use of advanced in-vehicle information systems (IVIS) and other complex devices such as smartphones while driving can lead to driver distraction, which, in turn, increases safety-critical event risk. Therefore, using methods for measuring driver distraction caused by IVIS is crucial when developing new in-vehicle systems. In this paper, we pres...

Automated driving is an active topic of research, while first results have already found their way into productive use. Nonetheless, nearly all of today’s vehicles are still non-automated. Most modern vehicles, however, are equipped with communication capabilities. Hence, combining these two developments and enabling sophisticated cooperative maneu...

The purpose of the International Conference on Computer-Human Interaction Research and Applications (CHIRA) is to bring together professionals, academics and students who are interested in the advancement of research and practical applications of interaction design & human-computer interaction. Five parallel tracks will be held, covering different...

The idea of transferring vehicle control to an automated system and thereby transforming from driver to passenger has raised safety concerns among potential users. To examine vehicle occupants’ perception (perceived safety and driving comfort, monitoring gaze behavior) of automated vehicle control in light of actual system experience, a driving sim...

Automated driving research over the past decades has mostly focused on highway environments. Recent technological developments have drawn researchers and manufacturers to look ahead at introducing automated driving in cities. The current position paper examines this challenge from the viewpoint of scientific experts. Sixteen Human Factors researche...

The present study aims to investigate user attitudes and behaviour when users interact with a corporate multimodal mobility sharing system, consisting of battery electric vehicles (BEVs), pedelecs (i.e. electric bicycles) and public transport. We analysed participants’ attitudes towards BEVs, pedelecs, public transport, and the underlying service t...

For a successful market introduction of Level 3 Automated Driving Systems (L3 ADS), a careful evaluation of human–machine interfaces (HMIs) is necessary. User preference has often focused on usability, user experience, acceptance and trust. However, a thorough evaluation of measures when applied to ADS HMIs is missing. We investigated the appropria...

Several tools have been developed over the past twenty years to assess the degree of driver distraction caused by secondary task engagement. A relatively new and promising method in this area is the box task combined with a detection response task (BT + DRT). However, no evaluation regarding the BT's sensitivity currently exists. Thus, the aim of t...

Automated driving is expected to bring several benefits such as improved traffic safety, reduced congestions and emissions, social inclusion, enhanced accessibility and higher driving comfort. A central human–machine interaction issue addresses the question of how automated vehicles should drive to ensure comfort and a positive driving experience....

The objective of this study was to investigate the influences of latency (i.e., technical system response time), action modality (button press, voice command) and display modality (head-mounted display, monitor) on the sense of agency (SOA). SOA is the experience of controlling one’s own actions and their corresponding effects in the environment. T...

Poster presentation of a driving simulator study executed to examine the passengers perception of automated vehicle control (AVC) compared to human vehicle control (HVC) during actual system experience in terms of driving experience (perceived safety and comfort) and monitoring gaze behavior (indicator of trust in the system).

Objective We observe the driving performance effects of gesture-based interaction (GBI) versus touch-based interaction (TBI) for in-vehicle information systems (IVISs). Background As a contributing factor to a number of traffic accidents, driver distraction is a significant problem for traffic safety. More specifically, visual distraction has a st...

Cell phone usage, especially texting while driving is common among drivers globally. Various experimental studies indicate that drivers compensate for the increased demand by reducing speed. However, naturalistic driving data analyses reveal only small changes in speed. For example, in an analysis of the SHRP 2 naturalistic driving data, only a sma...

Background The Cognitive Load Theory provides a well-established framework for investigating aspects of learning situations that demand learners’ working memory resources. However, the interplay of these aspects at the cognitive and neural level is still not fully understood. Method We developed four computational models in the cognitive architect...

Frequency of distraction while driving Secondary task engagement is one of the main causes of traffic accidents. In order to determine the crash risk, the prevalence of secondary task engagement has been examined in a variety of surveys and observational studies. However, the data in surveys and questionnaires may be subject to memory biases and o...

With the role change from driver to passenger provoked by driving automation, human factors such as a pleasant driving experience are considered important for a broad system acceptance and usage. However, allocating vehicle control to an automated system has been shown to raise safety concerns among potential users, and to be perceived differently...

Partially automated driving (PAD, Society of Automotive Engineers (SAE) level 2) features provide steering and brake/acceleration support, while the driver must constantly supervise the support feature and intervene if needed to maintain safety. PAD could potentially increase comfort, road safety, and traffic efficiency. As during manual driving, u...

The evaluation of the distraction potential of secondary task activities while driving has traditionally been focused on visual-manual tasks. In previous years, different test protocols have been developed and standardized to evaluate the distraction effects of in-vehicle information systems while driving. However, the assessment of cognitive distr...

The challenge of reducing worldwide greenhouse gas emissions has become increasingly important in recent years. Battery electric vehicles (BEVs) are a promising alternative having the potential for a CO2 neutral and sustainable utilization over the whole vehicle lifetime. However, BEVs limited range is still considered as one important usage barrie...

Promoting eco-driving with battery electric vehicles (BEVs) can help drivers reduce their average energy consumption and enhance the driving range of a BEV. The present study examined the influence of three persuasive strategies (feedback regarding energy consumption, gamification, and financial rewards) compared to a baseline condition (no feedbac...

Sequential abductive reasoning is the process of finding the best explanation for a set of observations. Explanations can be multicausal and require the retrieval of previously found ones from memory. The theory of abductive reasoning (TAR) allows detailed predictions on what information is stored and retrieved from memory during reasoning. In the...

Within a workshop on evaluation methods for automated vehicles (AVs) at the Driving Assessment 2019 symposium in Santa Fe; New Mexico, a heuristic evaluation methodology that aims at supporting the development of human–machine interfaces (HMIs) for AVs was presented. The goal of the workshop was to bring together members of the human factors commun...

Research has found that mobile phone call engagement while driving negatively affects driving performance. However, no studies exist characterising hand-held mobile phone calls while driving under naturalistic conditions that include aspects such as the duration of mobile phone subtasks and glance behaviour. Identifying the particularly distracting...

Kurzfassung: In der Industrie 4.0 wird der Interaktionsanteil zwischen Mensch und digitaler Technologie stetig zunehmen. Technostress steht für das Erleben von Überforderung besonders im Zusammenhang mit Informations-und Kommunikationstechnologien im Alltag. In dieser Studie sollte explorativ der Zusammenhang zwischen dem Erleben von Technostress i...

Problem: Some evidence exists that drivers choose to engage in secondary tasks when the driving demand is low (e.g., when the car is stopped). While such a behavior might generally be considered as rather safe, it could be argued that the associated diversion of attention away from the road still leads to a reduction of situational awareness, whic...