This research report aimed to present a team leader intervention model regarding when unexpected events arise in meetings. Onward, the model will form a starting point for the creation and validation of a team leader interventions inventory. Sixteen managers provided the empirical material for the construction of the model. The subjects proposed as many interventions as possible based on 10 different group meeting scenarios. In total, 327 interventions were proposed, which constituted the basis for a conceptual framework comprising six categories—Control, Inform, Initiate, Investigate, Support, and Avoid. Three of the categories correspond to classical leadership behaviours: the Control category to Authoritative Leadership and Task Behaviour and structure; the Support category to Democratic Leadership and Relationship Behaviour and consideration; and the Avoid category to Laissez-Faire Leadership, letting events pass without taking leadership. In addition, the conceptual framework includes three new categories in addition to the classical leadership theory. The Inform category is related to the controlling function. When the leader clarifies goals and how to achieve the goals, it is indirectly a controlling function. The Initiate category is related to launching procedural or distracting activities. Finally, the Investigate category is an almost necessary step ahead of the other categories. Before controlling, informing, initiating, supporting, or avoiding, the leader ought to investigate the causes of the disorder and then decide which intervention is most appropriate.

Shift-by-wire technology enables more options concerning the design, placement and functions of gear shifters compared to traditional gear shifters with manual transmission. These variations can impact usability and driver performance. There is a lack of research regarding the potential advantages and disadvantages of different types of gear shifters. The purpose of this study was to investigate the efficiency and subjective ease-of-use of mono- and polystable joystick gear shifter types at different complexity levels and with full or limited visibility. An experimental study with 36 participants was conducted. The results showed that monostable joysticks, especially those with an I/J-shape, were overall less efficient and easy to use than polystable joysticks. The highest complexity level clearly affected the efficiency for the monostable joystick with an I/J-shape (mono I/J) compared with the other gear shifter types. The monostable joystick with an I/J-shape (mono I/J) was also most affected by reduced visibility at the highest level of complexity, indicating that it was more prone to causing users to take their eyes off the road.

Shift-by-wire gear shifters are increasing the opportunities for individualization of functions and design. Though, greater variations can make gear shifters inefficient and error prone. Research regarding these aspects is still lacking. The aim of this study was to investigate how different gear shifter concepts were perceived in terms of Perceived Ease-of-Use and Task success, depending on their level of complexity, the shape of the shifter and stability of the shifter pattern. An experimental study was conducted with participants using six types of gear shifters on three levels of complexity. Results showed that the Monostable joystick received the lowest Perceived Ease-of-Use scores. Furthermore, the Rotary Toggle shifter with monostable function, had lowest Task success, which was supposed to be a result of e.g. unfamiliar design.

The purpose of this paper was to investigate how individual differences in glance strategy could impact the glance performance test defined in the NHTSA visual manual distraction guidelines. Better understanding of the test procedure could help development of new technology for safe driving. A custom in-vehicle information system was developed and assessed in a driving simulator by eighteen participants. The interfaces were designed according to recommendations in the NHTSA guidelines and contained manual radio-tuning tasks, sound settings tasks and six letter spelling tasks. Two of the six tested interfaces fully complied with the test. In addition, clear individual differences in glance strategy were found among the participants. Four individual glance strategies were identified. Two of these, long glancers and frequent glancers, highly affected the outcome of the compliance test. Participants belonging to the long glancers and the frequent glancers categories were identified as statistical outliers in many test cases. For example, if the individual values of these participants were replaced with sample mean, the number of complying interfaces would increase to five out of six, which is more in line with expectations for these interfaces. The results of this study show that individual variations in glance strategy exist. Also, these individual variations seem to have a non- negligible influence on the result when performance-testing of in-vehicle interfaces is done according to the NTHSA guidelines.

An in-vehicle haptic rotary device developed to interact with secondary tasks can provide haptic support to a visual interface and reduce the need to look away from the road. However, added haptic information intended to support interaction may distract the driver by adding cognitive load. This study examines how visual and haptic interfaces affect driver performance and if visual–haptic information could reduce effects of driver distraction. Four menu selection interfaces were compared: visual-only, visual–haptic with partly haptic support, visual–haptic with full haptic support, and haptic-only. The Lane Change Test was used with four measures. Interaction with the interfaces while driving caused increased driving deviation and delayed lane change initiation. The visual-only and the visual–haptic interface with partly haptic support caused erroneous crossed lanes. The haptic-only interface caused missed road signs. Full haptic support had the least negative effect on driver performance. In conclusion, haptic support could reduce effects of visual load without adding effects of cognitive load.

A driving simulator study was conducted to investigate the effects of carrying out a variety of tasks using two different types of contemporary in-car multifunctional interfaces: a touch screen interface and an interface manoeuvred by a rotary control. Participants drove on a curved rural road while performing tasks such as list scrolling, radio tuning, alphanumeric input and continuous adjustments. The results indicate that, in terms of task completion time and the number of glances made to the display, the optimal interface is dependent on the task being performed. The touch screen interface was better for alphanumeric input tasks and the interface manoeuvred by a rotary control was better for continuous adjustments and list scrolling. Alphanumeric input seems to be more demanding than other tasks, independent of the interface used. It was apparent in this simulator study that both interfaces affected the lateral control performance, but lateral control performance deteriorated to a greater extent when the touch screen interface was used, probably partially as a result of the lower display position.

Today, several vehicles are equipped with a visual display combined with a haptic rotary device for handling in-vehicle information system tasks while driving. This experimental study investigates whether a haptic addition to a visual interface interferes with or supports secondary task performance and whether haptic information could be used without taking eyes off road. Four interfaces were compared during simulated driving: visual only, partly corresponding visual-haptic, fully corresponding visual-haptic, and haptic only. Secondary task performance and subjective mental workload were measured. Additionally, the participants were interviewed. It was found that some haptic support improved performance. However, when more haptic information was used, the results diverged in terms of task completion time and interface comprehension. Some participants did not sense all haptics provided, some did not comprehend the correspondence between the haptic and visual interfaces, and some did. Interestingly, the participants managed to complete the tasks when using haptic-only information.

With the functional revolution in modern cars, evaluation methods to be used in all phases of driver-car interaction design have gained importance. It is crucial for car manufacturers to discover and solve safety issues early in the interaction design process. A current problem is thus to find a correlation between the formative methods that are used during development and the summative methods that are used when the product has reached the customer. This paper investigates the correlation between efficiency metrics from summative and formative evaluations, where the results of two studies on sound and navigation system tasks are compared. The first, an analysis of the J.D. Power and Associates APEAL survey, consists of answers given by about two thousand customers. The second, an expert evaluation study, was done by six evaluators who assessed the layouts by task completion time, TLX and Nielsen heuristics. The results show a high degree of correlation between the studies in terms of task efficiency, i.e. between customer ratings and task completion time, and customer ratings and TLX. However, no correlation was observed between Nielsen heuristics and customer ratings, task completion time or TLX. The results of the studies introduce a possibility to develop a usability evaluation framework that includes both formative and summative approaches, as the results show a high degree of consistency between the different methodologies. Hence, combining a quantitative approach with the expert evaluation method, such as task completion time, should be more useful for driver-car interaction design.

A driving simulator study was conducted to investigate whether the interaction with an in-vehicle multifunctional interface maneuvered by a rotary control can be improved if assisting haptics is provided. Two conditions were compared in the study, one in which neutral haptics was provided through the rotary control and one in which enhanced haptics was provided. Participants drove on a curved rural road while performing tasks such as list scrolling, radio tuning and text entry. The results indicated that, for radio tuning and settings adjustments tasks, interaction is improved when enhanced haptics is provided. It was shown that enhanced haptics can increase performance in terms of task completion time and can reduce the number and duration of glances made to the display. However, for alphanumeric input tasks, improvements are needed. Enhanced haptics seems to facilitate interaction with functions in which the sensations can be incorporated in an intuitive way.

There has been an increasing interest for in-vehicle interfaces that make use of haptic information. A simulator study was conducted to investigate whether haptic information can facilitate the interaction with an interface while driving. The conceptual in-car interface consisted of a visual menu of four textures displayed on a screen and corresponding haptic information displayed through the interaction device - a rotary device. The experimental conditions included either visual or haptic or both visual and haptic information. One advantage of the condition including only haptic information was that the participants' eyes remained on the road during the interaction. However, since the haptic interaction necessitated serial processing, the experimental task took longer when using only haptic information. Therefore the participants seem to have relied more on the visual information when it was available. The degradation in driving performance and mental workload assessment did not differ between the conditions.