From Table 3, it can be seen from the relationship of perceptual information between users and the parts that BI and CI are necessary for users to understand the parts. AI was needed between two particular parts as shown in Figure 3. Figure 3 illustrates the relationship between the various types of entities in terms of user-part, part-part, and user-part-part relationships and perceptual information for BI, AI, and CI for the tasks. For the user-part type, a certain part may need to be grasped by both hands and the index on the part indicates the operational direction; hence, both BI and CI need to be presented to users for specific operational tasks. For the part-part type, AI is essential for presenting the physical-assembling relationship between two specific parts; for example, subtask 1.3 in Table 1, where part F needed to be inserted into part C. For the subtask, the users did not need to directly operate part C by hand, but users grasped part F to insert it into part C. For the user-part-part type, it synthesizes the two types of parts above; the part is not only operated by the user body but also needs to be assembled with another part for a certain task to be complete. Therefore, BI, CI, and AI were exploited to present the applications of the parts to users.