An experimental study on the applicability of Fusion display and Overlay display of AR smart city data and information
Authors: Zheng Yu , Dong Zhanxun 
Published: June 2022

Background Smart digital twin cities digitally create virtual models of urban systems,It simulates the behavior of physical entities in a realistic environment with the help of data . And through virtual and real interactive feedback, data fusion analysis, decision iterative optimization and other means to design and build smart city platforms, Thus adding or extending new capabilities to smart city management.In conjunction with the trend towards AR glasses， paperless information design，the visual expression of information models, will be an important trend in the future, In demand for AR smart city related information reading, The right visual expression can assist managers in their exploration of the city's data.The key to AR information presentation is the presentation of the information, i.e. the way information is covered. Based on past research findings，There are two most conventional and operational ways to present，Fusion display and Overlay display. However, which one to use as the dominant form of presentation needs to be explored experimentally.Method In order to investigate which is more suitable for smart city data overlay, Fusion display or Overlay display. This experiment used Rhino 3D tools to build a 3D model of the city, The model contains three smart city operation scenarios: building equipment operation status, community power management system, and smart operation of business district，The content of the message is consistent in each scenario，while it is expressed through both Fusion display and Overlay display. Twenty identical questions and answers were set up for each comparison group's information presentation.The experiment will last for five weeks and the number of recruits will be 32, Recruiters are divided into groups A and each with sixteen members. The experiment required the subject to be able to read 12pt Arial regular characters without wearing glasses，Group A uses Fusion display, Group B uses Overlay display，Comparison of accuracy of information delivery and fatigue of information reading by subjects after test subjects have completed the same information questionnaire，The applicability of the interface was verified using the NASA- TLX scale. The specific experiments are as follows：(1)Information accuracy test session, this session is for the experimenter to wear the TOBII eye-movement instrument and conduct a 2 question visual expression test to ensure that the experimenter is familiar with the experimental process.(2) Cognitive experiment, the experimenter first read the questions carefully, after clarifying the questions, the experimenter picked up the tablet computer for AR overlay on the images, then the subject looked at the centre of the screen, received the "start" command, clicked on the centre of the screen and started reading to find information and complete the questions, a total of 5 groups of 20 questions, the experimenter recorded the time for each question.(3）Fatigue experiment, in this session, we ask the experimenter to test the fatigue of reading information in two types of visual information presentation: Fusion display and Overlay display，after the experimenter says "start", the experimenter will carry out a 10-minute information reading task of the same type of visual information presentation, read the information in the diagram The test is completed with multiple-choice questions. After reading the same type of visual expression, a five-minute break is taken and another visual expression reading task follows.(4）Interface usability questionnaires, in which the subjects are asked to evaluate the experimental interface according to their own circumstances, fill in an experimental research questionnaire and provide preferences and experimental suggestionsResultAt the end of the experiment, questionnaires, question completion schedules, eye-tracking point charts, thermograms, eye-beat charts and point analysis charts were collected from the AB group, and conclusions were generated through statistical analysis of the experimental data,The results are as follows：1) In terms of correctness data analysis, the Fusion display has a significantly lower correctness rate than the Overlay display2) In terms of completion efficiency, the Fusion display is significantly slower than the Overlay display in recognitionConclusion(1)Under the task-oriented experiment, users in the Fusion display were more focused on text.(2)Users who used the Fusion display f tended to search more in the central area.(3)Users' subjective feedback shows that fusion displays are preferred because they are more technological in nature(4)The range of eye movements of the subjects in the Fusion display is wider, while in the Overlay display, the trajectory of the subjects' eye movements is concentrated on the layer information. (5)The saturated color module has a higher number of user attentions