8 shows examples of pop-up cards designed using our system

Fig. 8 shows examples of pop-up cards designed using our system. The first was based on “The Wonderful Wizard of OZ” [2] pop-up book shown in Fig. 8 (a). We designed the piece shown in Fig. 8 (b) on our system in approximately C D E F G H I J Fig. 8. Pop-up cards designed using our system. 2h. Determining the heights and position was easy due to the error detection mechanism. Fig. 8 (d)-(f) show the templates generated by our system, which required approximately 2h for assembly in the final form shown in Fig. 8 (c). Fig. 8 (g) shows another example. This required approximately 2h for the design and 2.5 h for assembly into the final form shown in Fig. 8 (h). These results show that our system can handle reasonably complicated pop-up structures. We also conducted an informal preliminary user study. The test was conducted using a typical notebook personal computer with a keyboard and a mouse. We assigned two tasks: create a pop-up card of a building without using our system (Task 1) and perform the same task using our system (Task 2). Two test users participated in the study. They first completed Task 1. We then explained our system to them and had them practice with it for approximately 5 min before attempting Task 2. After they had finished both tasks, we conducted a brief interview to receive their feedback. &_' &`' &a' EQNNKUKQP &b' &c' Fig. 9. User study results. (a) The card produced by the first user in Task 1. (b) Collision occurs when the object in (a) is closed. (c) The card produced by the first user in Task 2. (d) The card produced by the second user in Task 1. (e) The card produced by the second user in Task 2. The first test user had never created pop-up cards before and had no knowledge of them. Fig. 9 (a) shows the card created by the first user in Task 1. It looks good, but it is difficult to close because of the collision shown in Fig. 9 (b). Fig. 9 (c) shows the card created by the first user in Task 2; it is simple but it closes correctly. The first user required 30 min to complete Task 1 (15 min for design and 15 min for construction) but only 20 min to complete Task 2 (10 min each for design and construction).