Designing Camera Monitoring Systems in Cars for Enhanced User Performance
Examensarbete för masterexamen
Industrial design engineering (MPDES), MSc
This Master Thesis was conducted at the Industrial Design Engineering program at Chalmers University of Technology in collaboration with Volvo Cars. The aim was to investigate which – and how- design parameters impact user performance (includes the ability to perceive the image, detect objects and estimating the distance to them), when Camera Monitoring Systems (CMS) replace rearview mirrors in cars and which benefits and drawbacks related to the user performance that a specific CMS prototype posed compared to driving with traditional car. It was furthermore to develop guidelines for how to apply this knowledge when designing CMS for increased user performance in cars. Literature studies, expert interviews, workshops, FMEA and user tests were some methods used for discovering this knowledge. The project resulted in a compilation of 20 design parameters that could affect user performance for CMS and which ten driving situations that are most relevant for the context of CMS. It also resulted in general guidelines for how to apply knowledge regarding researched design parameter’s impact on user performance in CMS that any industry party could apply in their work, but also in specific guidelines for how to develop the CMS prototype with regard of enhancing the user performance and experience. The literature studies led to knowledge regarding the impact that vertical and horizontal placement of the sideview camera, magnification, field of view, distance between the driver’s eyes and displays, image resolution and update rate, as well as pictorial depth cues have on distance estimations. Furthermore, how the lateral display placement, number of displays, field of view, presence of vehicle references, viewpoint as well image resolution and update rate impact overall control and object detection when driving. A parameter user test explored the impact zoom level (which depends on the parameters magnification and field of view) as well as vertical placement of the virtual inner rearview mirror’s camera have on distance estimation. Lower camera placement and zoom level made the user perceive distances as longer compared to higher ones. The users however experienced difficulties when estimating the distance using any configurations for the camera, due to the lack of present vehicle reference and since the direct vision through the rearview window was covered. Many design parameters affect the overall user performance and each design decision must therefore be made considering the others. There is no right or wrong way of how to perform this process, but the general guidelines present an order of which the decisions could be made to make the process more practically implemented based on the parameter characteristics. A user test comparing the user experience of driving the CMS prototype to a regular car led to insights and guidelines regarding which driving situations that the user experience needs to be improved, namely during lane changes, overtakings and driving in roundabouts. The CMS prototype guidelines also contains suggestions for how to reduce inconsistencies between the different display types and improvements regarding size, shape, surface finish, resolution, magnification and FOV of the displays, and some system functionalities that should be included.