New VR Navigation Techniques to Reduce Cybersickness

In nowadays state of the art VR environments, displayed in CAVEs or HMDs, navigation technics may frequently induce cybersickness or VR-Induced Symptoms and Effects (VRISE), drastically limiting the friendly use of VR environments with no navigation limitations. In two distinct experiments, we investigated acceleration VRISE thresholds for longitudinal and rotational motions and compared 3 different VR systems: 2 CAVEs and a HMD (Oculus Rift DK2). We found that VRISE occur more often and more strongly in case of rotational motions and found no major difference between the CAVEs and the HMD. Based on the obtained thresholds we developed a new "Head Lock" navigation method for rotational motions in a virtual environment in order to generate a “Pseudo AR” mode, keeping fixed visual outside world references. Thanks to a third experiment we have shown that this new metaphor significantly reduces VRISE occurrences and may be a useful base for future natural navigation technics

Non-visual Effects of Road Lighting CCT on Driver's Mood, Alertness, Fatigue and Reaction Time: A Comprehensive Neuroergonomic Evaluation Study

Good nighttime road lighting is critical for driving safety. To improve the quality of nighttime road lighting, this study used the triangulation method by fusing "EEG evaluation + subjective evaluation + behavioral evaluation" to qualitatively and quantitatively investigate the response characteristics of different correlated color temperature (CCT) (3500K, 4500K, 5500K, 6500K) on drivers' non-visual indicators (mood, alertness, fatigue and reaction time) under specific driving conditions (monotonous driving; waiting for red light and traffic jam; car-following task). The results showed that the CCT and Task interaction effect is mainly related to individual alertness and reaction time. Individual subjective emotional experience, subjective visual comfort and psychological security are more responsive to changes in CCT than individual mental fatigue and visual fatigue. The subjective and objective evaluation results demonstrated that the EEG evaluation indices used in this study could objectively reflect the response characteristics of various non-visual indicators. The findings also revealed that moderate CCT (4500K) appears to be the most beneficial to drivers in maintaining an ideal state of mind and body during nighttime driving, which is manifested as: good mood experience; it helps drivers maintain a relatively stable level of alterness and to respond quickly to external stimuli; both mental and visual fatigue were relatively low. This study extends nighttime road lighting design research from the perspective of non-visual effects by using comprehensive neuroergonomic evaluation methods, and it provides a theoretical and empirical basis for the future development of a humanized urban road lighting design evaluation system.Comment: 38 pages, 15 figures, 103 conference

Gaze behaviour in curve driving : Quantitative measurements of gaze velocity and yaw rate in simulated and real environments

Tämän tutkielman aiheena ovat spontaanit katsekäyttäytymisstrategiat kaarreajossa. Monien aiempien kaarreajotutkimusten käyttämät metodit eivät ole riittäneet erottelemaan mitä katsestrategiaa ajaja käyttää kääntyessään ajoneuvolla (Lappi, 2013, Itkonen et al. 2015). Tämän tutkielman metodit pystyvät eriyttämään eri strategioiden tuottamat tulosennusteet toisistaan horisontaaliseen katsenopeuden ja puolikkaan auton pystykiertymänopeuden avulla. Reittipistehypoteesin (WP) mukaan katse kohdistuu ajajan suunnitellulla reitillä oleviin pisteisiin. Tämä ennustaa, että katsenopeus ja puolikas auton pystykiertymänopeus korreloivat lineaarisesti ja niiden välinen suhde on -1:1. Tangenttipisteeseen (TP) ja muihin ajajan katsesuunnasta paikallaan pysyviin pisteisiin kohdistuvat katsestrategiat eivät ennusta mitään korrelaatiota. Pystykiertymänopeutta säädetään määrällisen analyysin mahdollistamiseksi ja kokeet suoritetaan niin simulaattorissa kuin oikealla ajoradalla reliabiliteetin ja validiteetin varmistamiseksi. Katse- ja telemetriadata tallennettiin koehenkilöiden ajaessa ympyrärataa hitaasti kiihtyvällä vauhdilla. Koetta ajettiin toisiaan muistuttavissa simulaattori- (n=15) ja ajorataympäristöissä (n=4). Puolikkaan auton pystykiertymänopeuden ja katseen horisontaalisen nopeuden välillä simulaattorissa löydettiin erittäin vahva (-0.91) ja ajoradalla vahva lineaarinen negatiivinen korrelaatio (-0.75) ja regressioanalyysin kulmakerroin molemmissa ympäristöissä lähestyi -1:1-suhdetta (-0.96 simulaattorissa ja -0.79 ajoradalla), kuten WP-hypoteesi ennusti. Ilmiö näkyy selkeästi myös yksittäisillä koehenkilöillä. Tulokset viittaavat siihen, että ajajien ensisijainen katsestrategia kohdistuisi kohteisiin suunnitellulla reitillä. Simulaattorin ja ajoradan tulosten pieniä eroavaisuuksia pohditaan lopuksi. Nämä kvantitatiiviset tulokset auttavat muodostamaan tarkempia malleja ajokäyttäytymisestä, mikä auttaa kehittämään itseajavia autoja ja ajoneuvo-ajaja-malleja. Käytetyt tarkat metodit ja mittaustulokset auttavat tekemään katsestrategioiden ja visuo-motoristen teorioiden mittaamisen ja vertaamisen helpommaksi eri ympäristöissä.This master’s thesis studies spontaneous gaze strategies when driving on a curved path. Methods used in many previous curve driving studies have not been sufficiently precise to differentiate between possible gaze strategies drivers use during cornering (Lappi, 2013, Itkonen et al. 2015). The methods in this thesis make it possible to differentiate between different gaze strategy predictions by comparing driver’s horizontal gaze velocity and half of car’s yaw rate. Waypoint hypothesis (WP), where gaze follows targets on the future path, predicts negative linear correlation and specific -1:1 ratio between horizontal gaze velocity and half of car’s yaw rate. Tangent point hypothesis (TP) and other travel point gaze strategies predict no correlation. In addition to previous study by Itkonen et al. (2015), the yaw rate is varied for quantitative analysis of the gaze behaviour and the experiment is conducted in two different environments, simulator and real test track, for reliability and validity. Gaze and car telemetry data was collected during a slow acceleration on a circular path in similar simulated (n=15) and real environment (n=4). As predicted by the WP hypothesis, the results show a very strong linear negative correlation between car’s half yaw rate and horizontal gaze velocity in simulator (-0.91) and strong linear negative correlation in test track (-0.75) and regression analysis shows slopes close to -1:1 ratio between the variables (simulator: -0.96 and test track: -0.79). The results can be clearly observed even on individual level. This suggests that primary gaze strategy when cornering in a curve is to pursue local flow on waypoints on the future path. The slight differences in results between simulator and test track experiment are discussed. These quantitative results contribute to making more precise models of driver behaviour, that can help advance autonomous car designs and driver-vehicle interaction models. The results also help to make gaze strategies and visuomotor process theories more measurable and comparable in different environments

Novel Approaches to Cognitive Load Estimation in Automated Driving Systems

Automation has become indispensable in all walks of everyday life. In driving environments, Automated Driving Systems (ADS) aid the driver by reducing the required workload and by improving road safety. However, the present-day ADS requires the human driver to remain vigilant at all times and be ready to take over whenever the driving task requires. Thus, continuous monitoring of the drivers is important for adopting ADS. Such monitoring can be done in ADS by measuring the cognitive load experienced by the drivers. Studies show various methods to estimate cognitive load, however, the state of the art in cognitive load estimation, particularly, the non-invasive ones suitable for ADS, still suffer from significant deficiencies. Thus, more research to improve the accuracy of cognitive load estimators is crucial for allowing the safe adoption of ADS. This thesis contains the analysis of non-invasive metrics that can be used as reliable indicators of cognitive load. Eye-tracking measures such as pupil size, eye-gaze, and eye-blinks from low-cost eye-trackers are analyzed. In addition to eye-tracking data, heart rate is also studied as an estimator of cognitive load. Furthermore, this thesis introduces a novel model-based approach to filter noisy physiological measurements for the real-time monitoring of cognitive load. The proposed measures will be beneficial to the development of more accurate metrics for cognitive load estimation, thereby contributing to the advancement of ADS. The thesis also contains a detailed description of two datasets collected at the HSLab.These datasets will be helpful to researchers interested in employing machine learning algorithms to develop predictive models of humans for applications in human-machine automation

Expert evaluation of aspects related to virtual reality systems and suggestions for future studies

Abstract. In this bachelor’s thesis, we review existing quantitative and qualitative research on virtual reality systems. We then present suggestions for performing a future study to combine the objective and subjective measurements of virtual reality experience. Additionally, we adapted an existing heuristics-based expert evaluation method to suit evaluating virtual reality systems. Using our method, we performed the expert evaluation on a selection of five modern consumer virtual reality systems to understand the connections between the subjective experience and the physical variables related to the virtual reality system. From this evaluation, we present findings that are used to construct discussion and to draw conclusions on these said connections. We found the most prominent conclusion to be that the experience of virtual reality is highly subjective and dependent on the content being viewed in virtual reality. Additionally, we concluded that some of the most important aspects in need of improvement are display resolution, lens design, user ergonomics, and lack of wirelessness. Finally, we state that two optimization problems are present; the first one being the optimization required to design a virtual reality system and the second one being the act of choosing a system to match a consumer’s preferred content.Tiivistelmä. Tässä kandidaatin tutkielmassa käymme läpi aiempaa kvantitatiivista ja kvalitatiivista tutkimusta virtuaalitodellisuusjärjestelmistä. Esitämme myös ehdotuksia myöhempää tutkimusta varten virtuaalitodellisuuteen liittyvien objektiivisten ja subjektiivisten mittausten yhdistämiseksi. Tämän lisäksi adaptoimme aiemman heuristiikkapohjaisen asiantuntija-arvioinnin sopimaan virtuaalitodellisuusjärjestelmien arviointiin. Käyttäen metodiamme toteutimme asiantuntija-arvioinnin viidellä modernilla kuluttajakäyttöön tarkoitetulla virtuaalitodellisuusjärjestelmällä ymmärtääksemme yhteyksiä subjektiivisen kokemuksen ja niiden fysikaalisten muuttujien välillä, jotka liittyvät virtuaalitodellisuusjärjestelmiin. Esitämme tämän asiantuntija-arvioinnin löydöksiä, ja luomme niiden avulla keskustelua, jonka avulla teemme mainittuihin yhteyksiin liittyviä johtopäätöksiä. Tärkein johtopäätöksemme oli se, että virtuaalitodellisuuden kokemus on erittäin subjektiivinen ja riippuvainen siitä sisällöstä, jota virtuaalitodellisuudessa koetaan. Aiemman lisäksi toteamme, että merkittävimpiä kehitystä kaipaavia osa-alueita ovat näytön resoluutio, linssien suunnittelu, käyttäjäergonomia ja langattomuuden puute. Viimeisenä totesimme, että virtuaalitodellisuusjärjestelmiin liittyy kaksi optimointiongelmaa; ensimmäinen liittyy järjestelmän suunnittelussa tapahtuvaan optimointiin, ja toinen liittyy sellaisen järjestelmän valitsemiseen, joka sopii kunkin kuluttajan suosimaan tarkoitukseen

Assistive Technology and Biomechatronics Engineering

This Special Issue will focus on assistive technology (AT) to address biomechanical and control of movement issues in individuals with impaired health, whether as a result of disability, disease, or injury. All over the world, technologies are developed that make human life richer and more comfortable. However, there are people who are not able to benefit from these technologies. Research can include development of new assistive technology to promote more effective movement, the use of existing technology to assess and treat movement disorders, the use and effectiveness of virtual rehabilitation, or theoretical issues, such as modeling, which underlie the biomechanics or motor control of movement disorders. This Special Issue will also cover Internet of Things (IoT) sensing technology and nursing care robot applications that can be applied to new assistive technologies. IoT includes data, more specifically gathering them efficiently and using them to enable intelligence, control, and new applications

Vulnerable road users and connected autonomous vehicles interaction: a survey

There is a group of users within the vehicular traffic ecosystem known as Vulnerable Road Users (VRUs). VRUs include pedestrians, cyclists, motorcyclists, among others. On the other hand, connected autonomous vehicles (CAVs) are a set of technologies that combines, on the one hand, communication technologies to stay always ubiquitous connected, and on the other hand, automated technologies to assist or replace the human driver during the driving process. Autonomous vehicles are being visualized as a viable alternative to solve road accidents providing a general safe environment for all the users on the road specifically to the most vulnerable. One of the problems facing autonomous vehicles is to generate mechanisms that facilitate their integration not only within the mobility environment, but also into the road society in a safe and efficient way. In this paper, we analyze and discuss how this integration can take place, reviewing the work that has been developed in recent years in each of the stages of the vehicle-human interaction, analyzing the challenges of vulnerable users and proposing solutions that contribute to solving these challenges.This work was partially funded by the Ministry of Economy, Industry, and Competitiveness of Spain under Grant: Supervision of drone fleet and optimization of commercial operations flight plans, PID2020-116377RB-C21.Peer ReviewedPostprint (published version