Mercedes Benz researchers investigate driving moods

The next time a TV commercial tells you that a car enhances your driving pleasure it may not just be a matter of purely subjective opinion. Mercedes Benz are working on a system that measures emotion while driving in an endeavor to bring some scientific analysis to the issue. In an attempt to understand what makes for an enjoyable driving experience experts from the Fraunhofer Institute in Rostock, Munich Technical University and Mercedes Customer Research have collaborated in a unique pilot study which involved testing various methods for measuring drivers' emotions.

The study used two models featuring different equipment and appointments for the field tests: the new C-Class and the Mercedes-Benz 190 E from 1983. Eight drivers aged between 33 and 53, a mix of men and women, drove the two saloons at a proving ground and negotiated different types of route including country roads, motorway stretches and a winding handling course while a data recorder logged details such as road speed, longitudinal acceleration and lateral acceleration as well as the cars' precise positioning data.

Basing their tests on the findings of American psychologist Paul Ekman, who found that facial expression is an undisputed indicator of emotions, scientists at Munich Technical University developed a process for interpreting facial expression by computer, thus making it possible to observe emotions over a longer period and in different situations, including when driving a car. Cameras inside the car recorded the drivers' facial expressions and 60,000 individual images were copied from the video recordings and then evaluated by computer for facial-expression recognition. A total of around one million images were analyzed in this way. In addition, the computer program also recorded the intensity of the expressions, allowing the scientists to differentiate between the degrees of typical emotions such as anger, sorrow, disgust, fear, enjoyment and surprise. Enjoyment readings which were above individually defined thresholds were interpreted as driving pleasure.

The driving pleasure measurements obtained by means of facial-expression recognition and voice analysis were accompanied by psychological questioning before and after each drive. The aim of this exercise was to find out what the drivers believed contributed to the level of driving pleasure. Unsurprisingly the statements made by the test participants were clearly dominated by aspects such as vehicle control and safety – areas in which the C-Class outshines the older Mercedes-Benz 190 E. These statements were sometimes at odds with the results of the facial recognition findings, which found some of the more experienced drivers enjoyed driving the older car, smiling when the rear end drifted slightly on tight bends of the handling course for example, showing that it all comes down to the type of driver.

The pilot study showed that driving pleasure can be measured using modern emotions-research methods and therefore can become a verifiable criterion for evaluating cars in future. Mercedes-Benz says it will continue its work in this field and integrate driving pleasure measurements into other scientific field tests involving drivers. In this way model development work is to attach even greater importance to driving pleasure — alongside safety, comfort and other measurable criteria. Mercedes Benz believes that such research will enable them to develop cars that, not only appeal to a drivers desire for safety and comfort, but also develop cars with a greater level of agility and dynamism to enhance driver enjoyment.