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Empirical Research on a Driver’s Preference for Onboard Navigation or Portable Navigation

A navigation system is an essential tool for drivers. Most vehicles are equipped with an onboard navigation system. In practice, drivers are willing to use a smartphone or portable device for navigation although both onboard navigation and mobile navigation have the same accuracy and onboard navigation systems have a larger screen. This study is designed to determine whether usability affects a driver’s preference for onboard navigation or portable navigation. A smartphone (5.5 " screen) and automobile central control panel (8" screen) were adopted as the portable and onboard navigation systems, respectively. Thirty subjects were recruited and asked to use the two devices according to instructions. Finger movement data such as finger movement speed and distance moved were collected to illustrate the efficiency of each device. Usability indexes such as duration, number of errors, and number of steps were included. The results indicated that subjects prefer the portable navigation system because they are accustomed to the smartphone input mode, though the onboard navigation has a better logical hierarchy and makes is easier for drivers to input their destination. These results are useful for automobile manufacturers and vehicle information system developers.