This document summarizes a study on the usability and safety of searching for radio stations using in-vehicle Digital Audio Broadcasting (DAB) devices. The study tested different strategies for searching stations based on station name, genre, and sub-genre using a driving simulator. Results showed searching by sub-genre took less time and eye fixation than other methods. User questionnaires also indicated DAB radio was perceived as slightly more satisfying to use than traditional FM radio. The study concluded that categorizing stations by genre and sub-genre can help users search more easily and safely while driving, and recommended further testing with more participants.

1. Searching Digital Audio Broadcasting radio stations: Usability and safetyissues for in-vehicledevices 1 M.Dibitonto1, M.Camilli1.2, A.Vona1, R.Grimaldi1, F. Di Nocera1,2, C.M. Medaglia1 1 C.A.T.T.I.D. – Sapienza University of Rome 2 L.A.F.C. – Dept. of Psychology -Sapienza University of Rome CHItaly 2011

3. Contents

4. User Interaction

5. Context(s) of Use

6. …2 CHItaly 2011

7. What is DAB? Digital Audio Broadcasting System is a digital technology for broadcasting radio station with an high quality of service. DAB+ is the most recent evolution and adds new multimedia services. 3 CHItaly 2011

8. Some data services CHItaly 2011 4 DLS EPG SLS iTxt

10. Test new type of contents/ formatContents and usability are key factors to make DAB appealing for a broad public 5 CHItaly 2011

11. Our focus In Italy 15mlns (42%) of users listens to analogue radio in their cars.* In this context introduction of new interactive system may affect the driving performance. Usability, User Experience and Safety are key factors to correctly design DAB+ services for an in vehicle context. *Menduni, 2003 6 CHItaly 2011

12. How wewillsearch a station with DAB? With DAB the number of radio stationswillincrease andsearchingcouldbecome a difficult task. DAB+ can supportserching/browsing station with: SL = station description EL = name of the Ensemble PT-1 = global genre of a station PT-2 = sub-genre Whichoneis the mosteffective, efficient and the best in terms of UX, usability and safety? 7 CHItaly 2011

13. The prototype 3.5 inch - 480x320px A prototypehasbeenimplemented to test differentsearchstrategies: name– PT1 (genre) – PT2 (sub-genre) 8 CHItaly 2011

14. Test environment Driving simulator Eyetracker DAB prototype Vibration feedback steeringwheel Camera for video recording The test environment to simulate an in-vehicle context . 9 CHItaly 2011

15. CHItaly 2011 10

16. 8 participants (2F – 6M, age 28.12, sd 3.18) A pre-test questionnaire A post-test questionnaire Analisys of eyefixations 11 CHItaly 2011

17. Results Resultsshowed no significantdifference in task durationwhile the analysis of eye scanning pattern showedthatuserspendless time lookingat the receiverwhileusing the PT-2 station search. 12 CHItaly 2011

18. Results Usabilityquestionnairescoresshowed a that DAB radio wasperceivedasslightly more satisfyingthan FM 13 CHItaly 2011

19. Conclusion and future works DAB will deeply change radio and the way the people interact with it giving new opportunities and challenges With DAB the number of radio station will increase and the user will face an higher complexity Generally the results showed that categorization of the program could help user searching a station. It seems to be particularly useful in automotive domain where hands-free implications could be critical for user safety The quali-quantitative approach used showed to be a suitable method to assess the usability of DAB technology Future studies will be aimed at testing the reliability of these results with a larger sample of users 14 CHItaly 2011

20. Thank you for your attention! Questions and (hopefully) answers. 15 CHItaly 2011