Speed vs. acceleration advice for advisory cooperative driving

Cooperation among vehicles is aimed to create a smooth traffic flow and minimize shockwaves and traffic jams. Cooperative adaptive cruise control (C-ACC) systems calculate acceleration values and exchange them between vehicles to maintain appropriate speed and headway. Before C-ACC technology gets mature, cooperative driving may already be made possible by advisory systems, keeping the drivers in the loop. While C-ACC systems are based on acceleration values, in conventional vehicles one of the main sources of information to the driver for maintaining appropriate speed is the speedometer. In this paper we present a study addressing the question of whether advisory systems should employ acceleration or speed values to advise the driver. Subjective results showed that preferences were approximately equally split between both systems. Objective results showed that acceleration advice caused more uniform speed in heavy traffic and more stable distance keeping, that speed advice led to more efficient accelerator pedal changes, and that letting drivers use their preferred advice resulted in a shorter time headway leading to a more effective traffic flow

Auditory messages for speed advice in advanced driver assistance systems

Simple tones in in-car systems are mostly used for status indication or warning and alerting purposes. We argue that simple tones can also be used for the purpose of advising drivers through an Advanced Driver Assistance System (ADAS). Our ADAS application is called Cooperative Speed Assistance (CSA), where drivers receive advice to slow down or speed up to coordinate their speed with the speed of other vehicles in the traffic. Two concepts of auditory messages are presented: Looping messages are played as long as the advice applies, while Toggle messages mark the beginning and the end of an advice. For each concept, two prototypes of simple-tone signals were designed based on existing guidelines about sound characteristics affecting urgency and evaluation by users. The temporal characteristics of the signals indicated how much or how fast drivers should adapt their speed. The concepts were evaluated by having users drive in a driving simulator. Objective measurements indicated that there was no difference in effectiveness between the two concepts. Subjective evaluation indicated that users preferred the Toggle concept

Speed vs. acceleration advice for advisory cooperative driving

Cooperation among vehicles is aimed to create a smooth traffic flow and minimize shockwaves and traffic jams. Cooperative adaptive cruise control (C-ACC) systems calculate acceleration values and exchange them between vehicles to maintain appropriate speed and headway. Before C-ACC technology gets mature, cooperative driving may already be made possible by advisory systems, keeping the drivers in the loop. While C-ACC systems are based on acceleration values, in conventional vehicles one of the main sources of information to the driver for maintaining appropriate speed is the speedometer. In this paper we present a study addressing the question of whether advisory systems should employ acceleration or speed values to advise the driver. Subjective results showed that preferences were approximately equally split between both systems. Objective results showed that acceleration advice caused more uniform speed in heavy traffic and more stable distance keeping, that speed advice led to more efficient accelerator pedal changes, and that letting drivers use their preferred advice resulted in a shorter time headway leading to a more effective traffic flow

Development of a questionnaire for identifying driver's personal values in driving

The speed behavior of drivers is influenced by their personal driving values. It is assumed that these personal values may differ between drivers. In this paper, we describe the development of the Personal Driving Values (PDV) questionnaire. The questionnaire is to be used as a means of identifying personal values of drivers underlying their speed behavior. The development of the questionnaire items was inspired by other driving questionnaires, but the aim is to extract factors that represent the personally relevant values in driving. A questionnaire consisting of 49 items was distributed to 250 drivers. An exploratory factor analysis resulted in a final 25-item questionnaire addressing six different driving values: Sustainable Driving, Driving Fun, Driving Relaxed, Safe Driving, Driving Efficiency (Time) and Avoiding Fines

Supporting behavior change in cooperative driving

Cooperation among vehicles is aimed to create a smooth traffic flow and minimize shockwaves and traffic jams. Before the technology gets mature, cooperative driving may already be made possible by involving the drivers. This paper reports a literature survey on two issues: 1) cooperation in traffic and motivations in driving; 2) persuasive technology and applications of extrinsic feedback. Informed by the literature survey, we propose concepts for supporting driver’s behavior change for the purpose of cooperative driving

Development of a questionnaire for identifying driver's personal values in driving

The speed behavior of drivers is influenced by their personal driving values. It is assumed that these personal values may differ between drivers. In this paper, we describe the development of the Personal Driving Values (PDV) questionnaire. The questionnaire is to be used as a means of identifying personal values of drivers underlying their speed behavior. The development of the questionnaire items was inspired by other driving questionnaires, but the aim is to extract factors that represent the personally relevant values in driving. A questionnaire consisting of 49 items was distributed to 250 drivers. An exploratory factor analysis resulted in a final 25-item questionnaire addressing six different driving values: Sustainable Driving, Driving Fun, Driving Relaxed, Safe Driving, Driving Efficiency (Time) and Avoiding Fines

ActiveShare: sharing challenges to increase physical activities

This paper discusses the use of social goal setting as a strategy to achieve persuasion through technology. This approach was applied in the design of ActiveShare a system developed to motivate people with sedentary lifestyles to increase their physical activity. In this system, users obtain and share their goals through challenges, which are posted on a social networking website. The paper describes the iterative design process followed, including concept tests, a focus group, and a field test with a fully functional prototype. Preliminary results are promising, although we found no significant increase on physical activity during the one week test. Suggested improvements to the design and plans for a follow up study are outlined