# A Needs-Based Augmented Reality System
## 4 Materials and Methods
### A Proof of Concept Prototype  
Concurrent research provides an extensive explanation of the triggers, sensors, and data requirements for the needs-based AR concept. As a result, it presents suggested guidelines to develop a needs-based AR system matching the concepts in Figures 7 and 8. The nine guidelines may be generalized to all needs in the fundamental human needs matrix beyond the basic needs discussed in this study. While the prior research focused on data analysis and need prediction, this study has a goal to connect all the elements and present a connected concept demonstrating the complete application process. These guidelines are  
Figure 8: Testing prototype architecture. Figure 7: Application Process. seen from the developer/designer's point of view. Following are the guidelines listed and exhibited for a prototype study. 1. Decide on the need you plan to satisfy with the AR experience. The case study is a restaurant business that satisfies the subsistence needs of hunger and thirst. The goal is to trigger the AR experience that interests the individual to visit the restaurant at the detection of the subsistence need. 2. Determine needs specific elements and requirements (context, personas, type)  
The subsistence need is dependent on internal and external contexts. Internal context represents the homeostasis imbalance of low blood glucose or dehydration. External context includes time, day, location, activity, and settings. The personas considered for this case are healthy individuals with no food allergies, and the type is needs-based triggered AR experience. 3. Select the trigger (homeostasis imbalance, habits, or incentives). Developing a collective experience requires the use of all triggers; however, to simplify the process, this case selects the use of habits trigger. The habits trigger requires the collection of several records for accurate need prediction. The records must include basic profile information in addition to context information, activity, and current need. 4. Develop the AR experience with multiple options and preferences for that particular need. This step aims to create an AR experience that targets particular needs and matches the business goals of the experience creator. Examples of such experiences (Figure 9) are retrieved from the menu AR application [43], and the SeeFood Augmented Reality Menu [44]. In the database, the AR experience should be paired with restaurant information such as restaurant name, location, cuisine, description, and such to create a point of interest and map directions for the individual. 5. Based on the need and trigger, select the appropriate sensors required to collect data. Since subsistence is the selected need and habits constitute the trigger, the required sensors must capture the following data: time, day, activity, location, and proximity with others. The use of a mobile device allows for capturing the time, day, GPS location (identified by the user as home, restaurant, or other), and proximity with others (identified by the user as being with family, friend, or no one). 6. Collect data and build a user profile and database. A sample of the database records representing the required data fields is presented in Figure 10. These records are extracted from the Context-Aware Personalization for Augmented Reality (CAP-AR) dataset [37]. 7. Decide and develop the analysis mechanism (a rule engine, predictive algorithms). The analysis mechanism of choice for the subsistence need based on habits are predictive algorithms. This choice is because habits are usually repetitive, and it is possible to train an algorithm to recognize them having enough records in the dataset. The analysis mechanism should detect the occurrence of a basic human need (trigger) and initiates the recommendation process, to present the individual with related AR experience. 8. Apply a recommendation process to select the AR experience specific to the individual's preferences.