318 research outputs found
Motion sickness in automated vehicles: principal research questions and the need for common protocols
No full textMotion sickness in automated vehicles (AVs) represents a key Human Factors concern that will negatively impact the passenger experience and, ultimately, public acceptance. Minimizing or avoiding motion sickness altogether, therefore, becomes a strategic design goal. In this articlewe propose principal research questions that need to be addressed as part of a concerted effort to understand the causative factors of motion sickness and the need to develop and apply common protocols to accelerate knowledge and subsequent innovation in this field. With the ultimate goal to provide guidelines to inform the design of future vehicles, the International Organization for Standardization standard (ISO) 2631-1 (1997) is taken as the starting point. The current standard provides estimates of the likelihood of motion sickness as a function of vertical motion input only. However, in the context of AVs, and in particular in the light of anticipated non-driving-related activities in such vehicles, the current standard is of limited use: The model has not been validated for horizontal and rotational motions or any potential multi-axes interactions; The standard was derived on the basis of the percentage of passengers reaching the point of emesis while less severe levels of motion sickness are of greater interest and may show a different relationship between the frequency and acceleration; Modulating factors that are able to regulate, adjust, or adapt sickness levels are not included, in particular vision and the associated concept of anticipation, passenger orientation, and reclination angles. Finally, the accumulation of motion sickness knowledge in this field is severely hampered by the absence of consistent study protocols. We here propose the identification and development of appropriate vibration measurements and motion sickness assessment and evaluation methods
Will autonomous vehicles make us sick?
No full textAutonomous vehicles have the potential to radically change the way we use and interact with our cars. Current thinking assumes that drivers will engage in non-driving tasks and, accordingly, future vehicle design may look dramatically different. However, the use cases envisaged are also known to exacerbate the incidence and severity of carsickness. This paper will discuss these scenarios with reference to the aetiology of carsickness and suggest design constraints to facilitate acceptable future autonomous vehicle design
Visually induced motion sickness
No full textAt times, people exposed to moving visual scenes may perceive themselves as moving even though they are, in fact, stationary. This sensation is sometimes experienced by people sitting in a railway carriage, in a station, when a neighbouring train slowly pulls away. Rather than sensing that the other train is leaving the station, they have the compelling feeling that their own train is moving in the opposite direction. This phenomenon, the feeling of moving brought about solely by a change in the visual scene, is called vection. Sustained exposure to moving visual scenes may not only produce vection, but can also provoke signs and symptoms of motion sickness such as dizziness, sweating, stomach awareness, and nausea and these adverse effects are now generally termed "visually induced motion sickness" (VIMS). VIMS is frequently reported in a variety of simulated or virtual environments such as flight and driving simulators, as well as in other contexts, such as at the cinema. It not only constitutes a nuisance to the user of these technologies, but also limits the usability of these technologies. Unlike other forms of motion sickness, such as seasickness, little is known about what conditions, or what aspects of moving visual scenes, are particularly provocative. Furthermore, research conducted thus far has generally investigated rotational motion patterns that are not representative of motion typically encountered in the real world. As a consequence, the work presented here has investigated the interrelationship between visual stimulus characteristics, VIMS, and vection during simulated forward and backward selfmotion (Le. along the fore-and-aft axis). In the first study, individuals were exposed to moving visual scenes that induced an illusion of motion in the fore-and-aft axis. These were presented either at a constant speed, or at a sinusoidally varying speed. Although varying the speed was expected to lead to higher levels of VIMS, this was not observed. The absence of an increased level of VIMS was hypothesised to be a consequence of the particular frequency employed (0.025 Hz). The frequency dependence of VI MS was then tested in a series of experiments. Noting that amplitude and acceleration covaried with frequency, it was found that within the range 0.025 - 1.6 Hz, VIMS peaked at 0.2 Hz. Using motion profiles with varying amplitude and acceleration, studies employing angular motion stimulation, on the other hand, had previously shown a peak in VIMS to occur at a frequency of approximately 0.06 Hz. This suggests that results obtained with angular motion stimulation cannot be extrapolated to scenarios involving linear motion stimulation in the fore-and-aft axis. The studies thus far isolated the effect of stimulus characteristics by preventing eye movements from occurring by means of fixation. A further study was conducted with the express purpose of investigating the effect of gaze shifting. It was found that the level of VIMS significantly increased with fixation away from the focus of expansion of a radial display. This suggests that the visual stimulus interacts differently with different portions of the retina. Real-world motion scenarios generally entail motion along different axes simultaneously. Most studies into VIMS have been restricted to single-axis motion and, although VIMS is assumed to increase with more complex motion scenarios, little is known about how VIMS changes with·increasing complexity. Comparing single- versus dual-axis motion, it was unexpectedly found that dualaxis motion did not lead to higher levels of VIMS, challenging the generally held assumption that VIMS is proportional to the degree of sensory conflict. The feasibility of predicting the incidence of VIMS based on an individual's motion sickness history as assessed by the revised Motion Sickness Susceptibility Questionnaire (MSSQ) was finally explored. Correlation coefficients were comparable to those observed with true motion suggestive of a common underlying mechanism between different forms of motion sickness. For the prediction of individual behaviour, the MSSQ was found to be of limited value in its current form. . A general finding was that vection consistently preceded the occurrence of VIMS, in line with the idea that vection is a necessary condition for VIMS to occur. This implies that future displays optimising the simulation of self-motion are likely to result in higher levels of VIMS. In addition, the findings that frequency, gaze direction, and multi-axis motion affected VIMS differently with simulated motion in the fore-and-aft axis as compared to angular motion profiles, indicate that angular motion commonly used to study VIMS may be of limited value.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
User interface design for highly and fully automated driving:designing for system trust and comfort in non-driving related tasks
No full textTwo new alkaloids from Melodinus hemsleyanus Diels
No full textTwo new monoterpenoid indole alkaloids, named 14,15-dihydro-14,15-epoxy-10-hydroxyscandine (1) and 15-hydroxy-meloscandonine (2), together with 12 known compounds, were isolated from the aerial parts of Melodinus hemsleyanus Diels. The structures of 1 and 2 were elucidated on the bases of 1D and 2D NMR spectra and MS. Two new compounds were evaluated for their PTP1B and Drak2 inhibitory effects, and inactivity
Carsickness: preventive measures
No full textTRL was contacted by Esure to provide guidelines and advice regarding measures to prevent and alleviate carsickness. Following a brief introduction to motion sickness, factors that are likely to affect the occurrence of carsickness will be presented. Particular emphasis is placed on the role of new in-vehicle entertainment systems and their likely exacerbating effect on carsickness. This may be of particular relevance to the occurrence of carsickness amongst children who not only tend to be most susceptible, but also most likely to use this type of in-vehicle entertainment systems. Finally, it is concluded with a list of tips to prevent or ameliorate carsickness
Carsickness: preventive measures
No full textTRL was contacted by Esure to provide guidelines and advice regarding measures to prevent and alleviate carsickness. Following a brief introduction to motion sickness, factors that are likely to affect the occurrence of carsickness will be presented. Particular emphasis is placed on the role of new in-vehicle entertainment systems and their likely exacerbating effect on carsickness. This may be of particular relevance to the occurrence of carsickness amongst children who not only tend to be most susceptible, but also most likely to use this type of in-vehicle entertainment systems. Finally, it is concluded with a list of tips to prevent or ameliorate carsickness
Visually induced motion sickness: Single- versus dual-axis motion
No full textThe majority of studies into visually induced motion sickness (VIMS) either use complex motion scenarios or are limited to single-axis motion. This study compared VIMS during single- and dual-axis motion. Twelve participants were exposed to (i) oscillating roll motion, (ii) linear motion in the fore-and-aft axis, and (iii) spiral motion, i.e. the summed direction of both of these flow vectors. Increased sensory conflict during exposure to spiral motion was hypothesised to increase the level of VIMS compared with exposure to its constituent motion patterns in isolation. Unexpectedly, spiral motion was not found to be more provocative than either of the two single-axis motion patterns, and this finding appears to be inconsistent with VIMS being determined by simple summation of the provocative stimuli. In the spiral motion condition, an atypical decrease in VIMS was observed during exposure, which was consistently preceded by a reduction in reported vection. It was hypothesised that the abstract nature as well as the unusual motion profile in the spiral motion condition may have rendered the stimulus increasingly ‘improbable’ and ultimately being disregarded, or ‘quarantined’, as an orientation cue by the central nervous system. The results are discussed in the context of methodological consequences for VIMS research and potential limitations of the use of abstract stimuli
One-component intrinsic self-healing polymer for coatings based on reversible crosslinking by Diels-Alder-cycloadditions
No full textSelf-healing can be achieved in polymer coatings by the incorporation of extrinsic materials, i.e. a healing agent is embedded into the coating (e.g., within capsules). In contrast the polymeric coating itself can feature the ability for healing \u96 for instance if reversible covalent bonds are introduced into the polymer network. The Diels-.Alder reaction is one prominent example to obtain reversibility within self-healing/mendable materials. In this context, a novel acrylic-based one-component polymer system has been synthesized, which contains both binding units for the Diels-Alder reaction (i.e. the maleimide and the furan moiety) as well as comonomers to tune the mechanical as well as thermal properties. The ATRP (atom transfer radical polymerization) of maleimide methacrylate (MIMA), furfuryl methacrylate (FMA) as well as of different alkylmethacrylates was utilized to synthesize well-defined functional terpolymers, which could be crosslinked subsequently via thermal treatment. The mechanical and thermal properties of these polymers have been investigated in detail. Moreover, the healing ability of these polymer coatings was studied. The influence of the crosslinking density, the kind of the comonomer and the healing temperature was investigated in detail. An efficient healing of these coatings could be observed. Additionally first attempts to tune the healing temperature of these coatings have been performed. The comonomers can also influence the required temperature for the retro-Diels-Alder reaction
Human-machine interface design development for connected and cooperative vehicle features
No full textThis paper discusses the design and evaluation of a number of connected and cooperative vehicle sign designs which have been developed within the UK Connected Intelligent Transport Environment project (UKCITE). As part of the first phase of the project, the sign design of four different applications were developed and evaluated: Emergency Electronic Brake Lights, Emergency Vehicle Warning, Traffic Condition Warning, and Road Works Warning. Whereas some of the feature made use of existing signs (e.g. road works warning), other applications required new signs. Appropriateness of the signs were evaluated by 21 participants who were shown videos of relevant traffic scenarios with the different signs displayed at appropriate moments. Results are discussed in the context of their appropriateness and suggest that existing standard signs may not appropriately represent new connected vehicle features requiring new design solutions
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