Navigation and orientation in 3D user interfaces: the impact of navigation aids and landmarks Author: Avi Parush, Dafna Berman International journal of Human-Computer Studies Reporter: Yang Kun Ou

Purpose The objective of this study was to examine how users acquire spatial cognition in an on- screen virtual environment.

Reference The notion of a ‘cognitive map’ has received much research attention (e.g. Evans, 1980; Hintzman et al., 1981; Chown et al., 1995) landmarks are the objects and elements in the survey knowledge and they are part of constructing the layout and relational configuration of the elements in the environment (Siegel and White, 1975; Heth et al., 1997; Chen, 1999; Wickens and Hollands, 1999)

Reference Findings indicated that map learning produced better performance with orientation tasks such as direction pointing, map drawing, and relative location estimation (Thorndyke and Hays- Roth, 1982; Moeser, 1986; Ruddle et al., 1997) Many studies showed that findings from the lab and the virtual environment can be generalized to the real world (e.g. Waller et al., 1998).

Method Participants –Included 109 participants (50 men, 59 women) –Age was 22.8(undergraduate and graduate student) –Previous experience with 3D environments, the mean rating was 2.7 (S.D.=1.3) –Previous experience navigating in the real world with map, the mean rating was 2.6 (S.D.=1.1)

Study Design The experimental design was a fully between- participant factorial 2x2 design based on two factors: –Landmarks—This factor included two conditions: the experimental environment with landmarks and without landmarks. –Navigation aid—This factor included two navigation aids: a map and a route list.

Experimental tasks The experiment included three tasks that were performed in the following sequence: –Learning: Navigating with navigation aids –Navigation test: Navigating without navigation aids –Orientation test: The task was performed in the same environment, with or without landmarks

Experimental system The experimental 3D environment was a T- shaped environment divided into 4 rooms

Experimental system Two identical views in the 3D environment, the right-hand picture with landmarks, and the left hand picture without landmarks.

Experimental system In each point the participant could rotate in intervals of 45 (e.g. eight possible directions) by pressing on right or left buttons displayed on both sides of the view. Movement in the environment was done in the point-to-point or teleporting method

Apparatus The map was a 40x56 cm cardboard with an overview of the 3D environment Two partial map views of the top left-hand room, the right-hand picture with landmarks, and the left-hand picture without landmarks

Technical set-up The 3D environment was built using Form-Z Renderzone The orientation task set-up was built separately using MS Visual Basic The experiment was performed using a personal PC with a Pentium 3 processor and a 17-in monitor with displayed pixels and 24 bit color depth

Procedure Participants were assigned randomly into one of the four experimental conditions Participants then received one task at a time on a small card All performed 10 navigation trials with the appropriate navigation aid Each trial started randomly from another point in the environment

Procedure Once the participant decided that the target object was found, she was required to press the Enter key on the keyboard Then she was given the next task and so on. Another experiment As before, each trial started randomly from another point in the environment. This order was randomized across all conditions and participants

Procedure Finally, each participant was given eighteen orientation tasks. A picture showing a certain point of view in the 3D environment was displayed along with the eight directional keys The participant was asked to point in the direction of a given object by pressing on the appropriate arrow button.

Measurements The performance measurements included the following: –Navigation duration –Number of navigation steps –Unessential navigation steps –Target correctness –Orientation correctness –Orientation response time –Orientation deviation

Results Learning: navigation with aids

Results

Learning transfer: switching to navigation without aids

Transfer: orientation test

Practical implications and research agenda The findings can be extended to approaches of training navigation and orientation. It was shown that there may be different strategies in how individuals acquire and use spatial cognition More adaptive approach in the utilization of various navigation aids should be employed in the learning or training of spatial skills.