Abstract: With the rapid development of intelligent vehicles and logistics, and the combination of
these two industries has promoted the emergence of driverless delivery cars. In order to improve the
safety, efficiency and user experience of the driverless delivery car, the design of the human-machine
interface (HMI) of the car’s exterior screen was studied. We first put forward the theory of
human-vehicle-environment relationship based on driverless delivery cars, and studied the design
requirements of vehicle exterior interface in view of the running scenario flow of delivery cars. On
this basis, the information architecture, multi-channel interaction mode and interface design of the
exterior interface of the driverless delivery car were discussed and practiced, and the usability test
was conducted regarding the preliminary prototype design of recycling function. The test results show
that the preliminary interactive prototype of the driverless delivery car’s exterior screen runs logically
smoothly and has high usability. The survey results show the users’ hope for the driverless delivery
car to be accurately located and the use of the points system for exchanging material rewards. This
research indicates that HMI design can improve the safety, efficiency and user experience of the
driverless delivery car. Through modifying and perfecting the design of the exterior screen with test and iteration, the design of the exterior screen will be continuously improved.

Key words: interaction design, driverless delivery cars, vehicle exterior screen, human machine
interface, design practice, usability test