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Total results: 302

Free-hand pointing for identification and interaction with distant objects

Year: 2013

Authors: S Rümelin,C Marouane,A Butz

In this paper, we investigate pointing as a lightweight form of gestural interaction in cars. In a pre-study, we show the technical feasibility of reliable pointing detection with a depth camera by achieving a recognition rate of 96% in the lab. In a subsequent in-situ study, we let drivers point to objects inside and outside of the car while driving through a city. In three usage scenarios, we studied how this influenced their driving objectively, as well as subjectively. Distraction from the driving task was compensated by a regulation of driving speed and did not have a negative influence on driving behaviour. Our participants considered pointing a desirable interaction technique in comparison to current controller-based interaction and identified a number of additional promising use cases for pointing in the car.

7 versions available

Increasing complexity of driving situations and its impact on an ADAS for anticipatory assistance for the reduction of fuel consumption

Year: 2013

Authors: C Rommerskirchen, M Helmbrecht

This paper presents a study of the impact of different complex situations on an advanced driver assistance system (ADAS) for anticipatory assistance for the reduction of fuel consumption. Different studies showed that it is possible to reduce the individual fuel consumption of drivers by extending the driver's anticipation horizon through an ADAS. But the influences of the driving situation on the success of such a system has not been researched yet. Therefore the driving simulator study which is presented in this paper deals with the impact of different traffic situations and its complexity on an anticipatory ADAS for fuel reduction in deceleration scenarios. For this, different rural and urban deceleration scenarios where chosen and situations of different complexity were implemented by changing traffic and environmental conditions. As the main focus of the ADAS lies on the reduction of the fuel consumption, this was one of the main variables which was measured. Additionally the glance time on the HMI was analyzed as an indicator for the manner how the system was used. The results showed that the degree of complexity of the chosen road traffic situations has generally no impact on the fuel consumption if it was driven without any assistance system. The glance times on the HMI of the ADAS shorten if a situation is more complex. But this does not lead to differences in the reduction of the fuel consumptions by the ADAS in different complex situations. The overall fuel consumption was reduced by about 10%. These results lead to the assumption that a good designed anticipatory ADAS reduces the driver related fuel consumption independently from the degree of the complexity of a situation.

3 versions available

Integrated simulation of attention distribution and driving behavior

Year: 2013

Authors: B Wortelen,A Lüdtke,M Baumann

A suitable distribution of attention to task demands is an essential component for efficient handling of multitasking situations. In most cases humans are not consciously aware of how they allocate attention to tasks. Yet they automatically weight their distribution to properties of the task like task value or the frequency of information events for a specific task. The Adaptive Information Expectancy (AIE) model was developed as a dynamic model of attention allocation and integrated into a cognitive architecture. It automatically derives the rate of information events for a task based on the interaction of a formal task model with the environment. The attention of the model is distributed according to these event rates and task priorities. Previous studies demonstrated that a dynamic driver model which uses the AIE model could reproduce many key characteristics of visual attention. In this paper it is shown, how changes in attention distribution are reflected in the task performance of the driver model for the three tasks of (1) keeping the car in the center of the lane, (2) keeping the speed close to 100 km/h and (3) solving a continuous in-vehicle secondary task. Driver model performance is compared to experimental data from a study on human drivers. Shortcomings of the driver model are discussed based on this comparison.

1 version available:

The influence of a driving task on movement times of goal directed hand-arm movements

Year: 2013

Authors: F Kremser, M Gebhart, M Stecher,K Bengler

A model based approach for the prediction of interaction times is needed for the evaluation of display and control concepts during the early virtual phase of the vehicle design process. The main objective of the described experiment is to assess the influence of a driving task on movement times of goal directed hand-arm movements. Another objective was to create a dataset to empirically model motion times and to support the adaptability of Fitts’ law for goal directed hand-arm movements in vehicle conditions. The experiments were conducted with 31 subjects in a fixed based driving simulator. In Scenario A the subjects performed a pointing only task, and in Scenario B, a driving task and the pointing task were performed together. Motions were captured using a VICON MX system. The variables scenario F(1, 27)=14.25, p<.001 and target distance F(4.97, 134.21)=174.962, p=.001 had a significant influence on movement time. Movements were performed 6% faster in Scenario B than in Scenario A. A stepwise linear regression showed that the distance from the origin of the movement to the target is the best predictor for the calculation of movement time.

3 versions available

Towards the automated recognition of assistance need for drivers with impaired visual field

Year: 2013

Authors: E Kasneci

Mobility enabled through driving is a crucial aspect of today’s social lives. It concerns young and elderly people and is critical for those among us suffering from visual field defects. Since driving primarily involves visual input, such people are often considered as unsafe drivers and banned from driving, although several recent studies, including our own, provide evidence that even severe visual field defects can be compensated through effective visual search strategies. In this context, this work pursues the challenging vision of adaptive driving assistance systems that take the visual deficits of the driver into account to enable a safer driving experience. The main challenges towards this vision are: (1) individual analysis and detection of visual field defects, (2) online analysis of visual search behavior, and (3) integrated analysis of visual deficits, search behavior, and traffic objects to identify and draw the driver’s attention towards potential hazards. Each of the above challenges is approached by customized methods. For (1), a mobile method for the assessment of the visual field and an algorithm for the recognition of the type of the visual field defect are proposed. For (2), an online probabilistic method is combined with algebraic analysis of the driver’s gaze. For (3), a detailed analysis of the driving scene is combined with the above methods to reliably detect hazardous traffic objects that might be overlooked by the driver. The methods were evaluated on real-world data from driving experiments with patients suffering from visual field defects. In combination, they improve over state-of-the-art techniques by being flexible, adaptive, and reliable. The feasibility of detecting objects that might be overlooked by the driver, and thus an adaptive assistance need, is demonstrated in different user studies. The methods developed in this work have a broad applicability that reaches beyond the driving context. Their application to a variety of tasks involving visual perception might help better understand its underlying mechanisms. Some of these tasks are already being investigated and will also be presented in this thesis.

4 versions available

Traffic Light Assistant–Can take my eyes off of you

Year: 2013

Authors: M Krause, V Knott,K Bengler

A traffic light assistant on a smart phone is assessed with an eye tracker in real traffic. The system is displayed on three different screen sizes on a nomadic device and gaze durations are measured. Another condition of the experiment includes an acoustic click when the display content changes to reduce glance frequency. The acoustic click as an auditory hint does not reduce the frequency of gazes, as expected. The gaze durations can get shorter as display size increases, but this does not necessarily reduce the percentage of time an in-vehicle information system (IVIS) is looked at. Subjective ratings indicate that display contents can even be shown too big. Overall, the gaze durations are in line with current limits, even when displayed on a small screen. A set of gaze histograms and calculated gaze metrics is provided to enable comparison with other experiments and IVIS.

4 versions available

Comparison of in-car touchpads with adaptive haptic feedback

Year: 2012

Authors: A Blattner,K Bengler, W Hamberger

Two in-car touchpads with adaptive haptic feedback are specified in the context of this contribution. These innovative control elements enable an easy and intuitive handling of modern car infotainment systems. The current paper presents the results of a field experiment comparing a touchpad with realistic haptic feedback via sensible and operable elements to a touchpad with haptic feedback via vibration of the touchpad surface in a real driving situation.

2 versions available

Driving with a partially autonomous forward collision warning system: How do drivers react?

Year: 2012

Authors: E Muhrer, K Reinprecht,M Vollrath

Objective: The effects of a forward collision warning (FCW) and braking system (FCW+) were examined in a driving simulator study analyzing driving and gaze behavior and the engagement in a secondary task. Background: In-depth accident analyses indicate that a lack of appropriate expectations for possible critical situations and visual distraction may be the major causes of rear-end crashes. Studies with FCW systems have shown that a warning alone was not enough for a driver to be able to avoid the accident. Thus, an additional braking intervention by such systems could be necessary. Method: In a driving simulator experiment, 30 drivers took part in a car-following scenario in an urban area. It was assumed that different lead car behaviors and environmental aspects would lead to different drivers’ expectations of the future traffic situation. Driving with and without FCW+ was introduced as a between-subjects factor. Results: Driving with FCW+ resulted in significantly fewer accidents in critical situations. This result was achieved by the system’s earlier reaction time as compared with that of drivers. The analysis of the gaze behavior showed that driving with the system did not lead to a stronger involvement in secondary tasks. Conclusion: The study supports the hypotheses about the importance of missing expectations for the occurrence of accidents. These accidents can be prevented by an FCW+ that brakes autonomously. Application: The results indicate that an autonomous braking intervention should be implemented in FCW systems to increase the effectiveness of these assistance systems.

8 versions available

Enhancement of driver anticipation and its implications on efficiency and safety

Year: 2012

Authors: D Popiv

This dissertation presents the research performed on the anticipatory advanced driver assistance system with visual and haptic modalities of integrated human-machine interface, whose purpose is to enhance driver abilities in performing deceleration maneuvers in the most efficient (with reduced fuel consumption) and, which is applicable in potentially critical situations, safe manner. This is done by presenting information about upcoming deceleration situations and suggestions of recommended course of driving actions. The system’s aim is to pursue the driver to extensively exploit the motor torque during deceleration phases instead of conventionally applying pressure on the brakes. The driver is advised by the system when the optimal coasting phase should be initiated, i.e. when to release the accelerator and let the vehicle slow down using engine braking to the upcoming lower speed without pressing the brake pedal. If the driver does not immediately follow the initial advice of the system and therefore is not able to solely coast the vehicle to the lower target speeds, moderate braking is suggested at the appropriate point in time. As an implication, the extreme decelerations are to be avoided in safety critical situations by assisted preceding coasting and moderate braking phases. Three experiments are performed to validate the influence of proposed advanced driver assistance system on driver behavior. In the first experiment, different visual assistance concepts are investigated. Innovative Bird’s-Eye View concept is subjectively evaluated as the most suitable human-machine interface for the system, which information about upcoming deceleration situations and proposition of coasting actions result in estimated 4% of fuel reduction throughout a drive. In the second experiment, possible inaccuracies of presented information are considered. Results show, that drivers are not affected by partially missing situational data, as long as the information presented gives important situational cues for the comprehension of the upcoming situation. Also, no one has blindly followed advices of the system without having observed the development of driving situation in reality. The third experiment proved additional benefit of multimodal human-machine interface: haptic feedback via impulse of an active gas pedal, also known as force-feedback pedal, decreases reaction times and results in 7.5% reduction of estimated fuel consumption.

1 version available:

Evaluation of Automotive HMI Using Eye-Tracking-Revision of the EN ISO 15007-1 & ISO TS 15007-2

Year: 2012

Authors: C Lange

This paper presents the revision of documents EN ISO 15007-1 and ISO/TS 15007-2 which was done by the ISO TC22SC13WG8 working group consisting of eye-tracking specialists worldwide. Both ISO documents were published in 1999. Since then many research studies were conducted, which lead to an increasing level of knowledge about eye-movement behavior. In parallel to that, eye-tracking technology developed enabling fully automated data analysis. Due to that both standards were revised in the ISO TC22SC13WG8 working group to include latest findings in eye-movement behavior and latest developments in eye-tracking technology.

1 version available: