Vibrotactile pedals : provision of haptic feedback to support economical driving

The use of haptic feedback is currently an underused modality in the driving environment, especially with respect to vehicle manufacturers. This exploratory study evaluates the effects of a vibrotactile (or haptic) accelerator pedal on car driving performance and perceived workload using a driving simulator. A stimulus was triggered when the driver exceeded a 50% throttle threshold, past which is deemed excessive for economical driving. Results showed significant decreases in mean acceleration values, and maximum and excess throttle use when the haptic pedal was active as compared to a baseline condition. As well as the positive changes to driver behaviour, subjective workload decreased when driving with the haptic pedal as compared to when drivers were simply asked to drive economically. The literature suggests that the haptic processing channel offers a largely untapped resource in the driving environment, and could provide information without overloading the other attentional resource pools used in driving

Encouraging eco-driving: the case for vibrotactile information presented through the accelerator pedal

different methods of in-vehicle information presentation to encourage fuel efficient driving behaviours, and to explore the theoretical justifications for the use of in-vehicle haptic stimuli (related to the sense of touch), presented at the site of control (i.e., the accelerator pedal). A review of the literature concerning design, behaviour, and energy use led on to an exploration of Ecological Interface Design, and the Skills, Rules, and Knowledge (SRK) taxonomy of human behaviour, particularly with regard to haptic information presented through the accelerator pedal. Survey and on-road studies served to shed light on the practice of eco-driving more generally, in terms of attitudes, knowledge, behaviour, and cognition. Then followed an analysis of expert eco-drivers’ decision-making processes. This made use of the decision ladder, an analysis tool rooted in the SRK framework. Results of the analysis went on to inform the design of an in-vehicle information system that aimed to support optimum use of the accelerator pedal, both for efficient accelerations, and for maximisation of the coasting phase of the vehicle when approaching deceleration events. A simulator-based experiment served to assess the effects of presenting stimuli in different sensory modes (visual, auditory, vibrotactile), resulting in the conclusion that vibrotactile feedback, being both effective and well received by participants, is indeed suitable for the support of eco-driving. In a second simulator-based study, coasting support provided the sole focus; acceleration behaviours were not investigated. Results suggested that there is a minimum distance away from an event below which stimuli encouraging removal of the foot from the accelerator pedal (in order to coast down to the desired speed)have neither a beneficial effect on driving performance, nor attract positive acceptance ratings from users. Moreover, stimuli presented farther from the event supported greater benefits in terms of efficiency. Overall findings are discussed with regard to the practical aspect of how best to support eco-driving in the private road vehicle, and in relation to the theoretical justifications for accelerator-based haptic feedback in the vehicle

WATI: Warning of Traffic Incidents for Fuel Saving

Traffic incidents (heavy traffic, adverse weather conditions, and traffic accidents) cause an increase in the frequency and intensity of the acceleration and deceleration. The result is a very significant increase in fuel consumption. In this paper, we propose a solution to reduce the impact of such events on energy consumption. The solution detects the traffic incidents based on measured telemetry data from vehicles and the different driver profiles. The proposal takes into account the rolling resistance coefficient, the road slope angle, and the vehicles speeds, from vehicles which are on the scene of the traffic incident, in order to estimate the optimal deceleration profile. Adapted advice and feedback are provided to the drivers in order to appropriately and timely release the accelerator pedal. The expert system is implemented on Android mobile devices and has been validated using a dataset of 150 tests using 15 different drivers. The main contribution of this paper is the proposal of a system to detect traffic incidents and provide an optimal deceleration pattern for the driver to follow without requiring sensors on the road. The results show an improvement on the fuel consumption of up to 13.47%

Analyzing Measures for the Construct “Energy-Conscious Driving”: A Synthesized Measurement Model to Operationalize Eco-Feedback

During the last several years, a large number of studies have dealt with eco-driving and have defined rules for driving vehicles more ecologically, eco-friendly, and energy efficiently. These rules are vague or insufficient for achieving their purpose, and the construct “energy- conscious driving” is unsatisfactorily defined. To structure available research and develop a more extensive concept of energy-conscious driving, a measurement model for energy- conscious driving is introduced. The model stems from a literature review conducted to identify six groups of measures for energy-conscious driving, and a synthesis of these groups to identify dependencies between them. This paper contributes to theory by building on existing knowledge on eco-driving through an analysis of available literature and describing dependencies between our six measures of energy-conscious driving. Based on our model, researchers can evaluate different eco-feedback designs and practitioners can implement more specific eco-feedback systems for improved user performance

A Review of Shared Control for Automated Vehicles: Theory and Applications

The last decade has shown an increasing interest on advanced driver assistance systems (ADAS) based on shared control, where automation is continuously supporting the driver at the control level with an adaptive authority. A first look at the literature offers two main research directions: 1) an ongoing effort to advance the theoretical comprehension of shared control, and 2) a diversity of automotive system applications with an increasing number of works in recent years. Yet, a global synthesis on these efforts is not available. To this end, this article covers the complete field of shared control in automated vehicles with an emphasis on these aspects: 1) concept, 2) categories, 3) algorithms, and 4) status of technology. Articles from the literature are classified in theory- and application-oriented contributions. From these, a clear distinction is found between coupled and uncoupled shared control. Also, model-based and model-free algorithms from these two categories are evaluated separately with a focus on systems using the steering wheel as the control interface. Model-based controllers tested by at least one real driver are tabulated to evaluate the performance of such systems. Results show that the inclusion of a driver model helps to reduce the conflicts at the steering. Also, variables such as driver state, driver effort, and safety indicators have a high impact on the calculation of the authority. Concerning the evaluation, driver-in-the-loop simulators are the most common platforms, with few works performed in real vehicles. Implementation in experimental vehicles is expected in the upcoming years.This work was supported in part by the ECSEL Joint Undertaking, which funded the PRYSTINE project under Grant 783190, and in part by the AUTOLIB project (ELKARTEK 2019 ref. KK-2019/00035; Gobierno Vasco Dpto. Desarrollo económico e infraestructuras)

A Review of Shared Control for Automated Vehicles: Theory and Applications

The last decade has shown an increasing interest on advanced driver assistance systems (ADAS) based on shared control, where automation is continuously supporting the driver at the control level with an adaptive authority. A first look at the literature offers two main research directions: 1) an ongoing effort to advance the theoretical comprehension of shared control, and 2) a diversity of automotive system applications with an increasing number of works in recent years. Yet, a global synthesis on these efforts is not available. To this end, this article covers the complete field of shared control in automated vehicles with an emphasis on these aspects: 1) concept, 2) categories, 3) algorithms, and 4) status of technology. Articles from the literature are classified in theory- and application-oriented contributions. From these, a clear distinction is found between coupled and uncoupled shared control. Also, model-based and model-free algorithms from these two categories are evaluated separately with a focus on systems using the steering wheel as the control interface. Model-based controllers tested by at least one real driver are tabulated to evaluate the performance of such systems. Results show that the inclusion of a driver model helps to reduce the conflicts at the steering. Also, variables such as driver state, driver effort, and safety indicators have a high impact on the calculation of the authority. Concerning the evaluation, driver-in-the-loop simulators are the most common platforms, with few works performed in real vehicles. Implementation in experimental vehicles is expected in the upcoming years

Sustainability, transport and design: reviewing the prospects for safely encouraging eco-driving

Private vehicle use contributes a disproportionately large amount to the degradation of the environment we inhabit. Technological advancement is of course critical to the mitigation of climate change, however alone it will not suffice; we must also see behavioural change. This paper will argue for the application of Ergonomics to the design of private vehicles, particularly low-carbon vehicles (e.g. hybrid and electric), to encourage this behavioural change. A brief review of literature is offered concerning the effect of the design of a technological object on behaviour, the inter-related nature of goals and feedback in guiding performance, the effect on fuel economy of different driving styles, and the various challenges brought by hybrid and electric vehicles, including range anxiety, workload and distraction, complexity, and novelty. This is followed by a discussion on the potential applicability of a particular design framework, namely Ecological Interface Design, to the design of in-vehicle interfaces that encourage energy-conserving driving behaviours whilst minimising distraction and workload, thus ensuring safety

New knowledge and methods for mitigating driver distraction

Driver distraction is the diversion of attention to a non-driving related activity. It has been identified as major cause of accidents. Even as we move away from traditional ‘driver’ and towards highly-automated vehicles, distraction remains an important issue. A distracted driver could still potentially miss a handover of control message from the car, or have a reduced awareness of the traffic environment. With the increased number and complexity of new features being introduced in vehicles, it is becoming more important to understand how drivers interact with them, to understand the benefit they offer in helping the driver to focus on-road, but also to identify their limitations and risks. Thereby it is important to consider that the interaction between human and technology, e.g. driver distraction, can be described by many aspects. To learn the most about the interaction between user and technology, it is important to select a suitable measure and to utilise that measure in best practice, which can be hard to find in literature. This research project is divided into two research streams that investigate the opportunities of new in-vehicle interfaces to mitigate driver distraction and that research how to efficiently identify measures for the ergonomic evaluation of in-vehicle interfaces. Research stream one, comprising four studies, evaluated tactile information as a new interface technology to mitigate distraction in manual and automated cars. Tactile perception requires physical contact between the driver and the device delivering the feedback. It can be decreased by clothing. In the first user trial it was evaluated, for the first time, how shoe type, gender, and age influence the driver’s perception of a tactile pedal. Shoe type did not, but gender, age, and the feedback’s duration and amplitude did influence the perception. In some durations and amplitudes, the feedback was recognised by all participants and was rated highly intense, both aspects a warning should have. Next, it was evaluated how fast people would react to a tactile warning compared to a traditional auditory warning and an auditory-tactile warning. The participants reacted significantly slower to the tactile warning. Following, a tactile warning might not be suitable as an in-vehicle warning. However, adding an auditory component to the tactile warning increases its efficiency and people missed less auditory-tactile compared to auditory warnings. Newly introduced interfaces, such as tactile interfaces, put an effort on drivers to adjust to them and might lead to unsafe interactions. In the third and fourth study, it was investigated how a driver’s trust effects the reaction time and glance behaviour. Trust was not associated with the reaction time towards a tactile warning signal, but it influenced the glances at a voice-navigation interface that was new for the majority of the participants. The findings can be utilised to increase the trust in the interface dialogue and thereby decrease a driver’s time glanced off-road. Research stream two investigated how Human-Machine-Interface (HMI) engineers can be supported in the comparison and selection of measures (e.g. a usability score) to evaluate the ergonomics of in-vehicle devices, for example to measure driver distraction. Industry projects are often restricted by tight deadlines and limited availability of equipment. Measure selection can then become a time critical issue. In published literature, there existed no guidelines to support this task. In four rapid prototyping evaluations, an interface was developed that can aid HMI-engineers in the comparison and selection of measures for an ergonomic evaluation. The tool functions as knowledge management and foresees to inform users about the best practice to utilise a measure, tips to set-up required equipment, and templates for the measure, for example templates for the analysis or electronic versions of questionnaires