evaluating motion constraints for 3d wayfinding in immersive and desktop virtual environments

15
Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments Niklas Elmqvist [email protected] M. Eduard Tudoreanu [email protected] Philippas Tsigas [email protected] CHI 2008 – Florence, Italy

Upload: niklas-elmqvist

Post on 22-Apr-2015

1.572 views

Category:

Technology


0 download

DESCRIPTION

Motion constraints providing guidance for 3D navigation have recently been suggested as a way of offloading some of the cognitive effort of traversing complex 3D environments on a computer. We present findings from an evaluation of the benefits of this practice where users achieved significantly better results in memory recall and performance when given access to such a guidance method. The study was conducted on both standard desktop computers with mouse and keyboard, as well as on an immersive CAVE system. Interestingly, our results also show that the improvements were more dramatic for desktop users than for CAVE users, even outperforming the latter. Furthermore, the study indicates that allowing the users to retain local control over the navigation on the desktop platform helps them in familiarizing themselves with the 3D world.

TRANSCRIPT

Page 1: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

Evaluating Motion Constraints for 3D

Wayfinding in Immersive and Desktop Virtual

Environments

Niklas [email protected]

M. Eduard [email protected]

Philippas [email protected]

CHI 2008 – Florence, Italy

Page 2: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

2

Where am I? Where am I going?

Page 3: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

3

How to Aid Wayfinding?

• Wayfinding: navigation to solve specific task– Performed on cognitive map– Poor map leads to poor performance

• Problem: aiding wayfinding by supporting cognitive map building– Motion constraints and guides– Example: sightseeing tour of new city

Page 4: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

4

Cognitive Maps

Hotel

Tour Eiffel

Montmartre

Notre DameLouvre

Airport (CDG)

?

Page 5: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

5

Supporting Cognitive Maps

• GC: Global coverage– Expose viewer to whole environment

• CM: Continuous motion– Support spatial relations

• LC: Local control– Learning by doing

Hotel

Tour Eiffel

Montmartre

Notre DameLouvre

Airport (CDG)

?

Page 6: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

6

Virtual vs. Physical Worlds

• Why is wayfinding more difficult in virtual worlds?– Low visual fidelity– Mouse and keyboard poorly mapped to

3D navigation– Lack of sensorial cues

• High cognitive load on users

Page 7: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

7

Reducing Cognitive Load

• Method: Immersive Virtual Reality– Full 3D input– Full 3D output

• But: No widespread use, expensive (?)

• Mouse and keyboard are standard

Page 8: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

8

Guiding using 3D Motion Constraints

• Tour-based motion constraints (GC)• Smooth animation (CM)• Spring-based control (LC)

Page 9: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

9

User Study

• Hypotheses– H1: Guiding navigation helps wayfinding– H2: Local control improves familiarization– H3: Navigation guidance has higher impact for

desktop than for CAVE

• Controlled experiment (mixed design)• Two experiment sites• 35 participants

– 16 (4 female) on desktop computer– 19 (2 female) on CAVE system

Page 10: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

10

Factors

• Platform (BS): desktop or CAVE• Navigation (BS/WS): free, follow,

spring• Scenario (WS): outdoor, indoor,

infoscape, conetree• Collect distance, error, and time

Page 11: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

11

Procedure

• Phase I: Familiarization– Create cognitive map (5 minutes)– Supported by guidance technique– Three target object types

• Phase II: Recall– Locate two targets on overhead map

• Phase III: Evaluation– Collect third target in world – No navigation guidance

Page 12: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

12

Results – Summary

• Navigation method:– Free navigation: CAVE better– Motion constraints: desktop significantly

better (p < 0.05) [H1]

• Desktop platform:– Spring-based guidance gave better

accuracy than other methods [H2]– Navigation guidance more efficient than

free flight [H3]

Page 13: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

13

evaluation error

0

0,05

0,1

0,15

0,2

0,25

0,3

follow free spring

no

rma

lize

d e

rro

r

CAVE

Desktop

average time per target

0

5

10

15

20

25

30

35

40

45

50

follow free spring

tim

e p

er

targ

et

(se

co

nd

s)

CAVE

Desktop

recall distance

0

0,05

0,1

0,15

0,2

0,25

0,3

follow free spring

no

rma

lize

d e

rro

r

CAVE

Desktop

Results – Details

Page 14: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

14

Conclusions

• Navigation guidance based on tours– Improve cognitive map building

• Evaluation on desktop and CAVE– Navigation guidance on desktop

outperforms CAVE– Less focus on interaction mechanics

• Take-away message: removing (some) freedom in 3D navigation may actually help wayfinding!

Page 15: Evaluating Motion Constraints for 3D Wayfinding in Immersive and Desktop Virtual Environments

15

Questions?

• Main findings:– Free-flight best on

immersive platforms– 3D guidance: desktop

outperform CAVE– Allowing local control

helped desktop

– Removing freedom improves performance

• Contact information– Niklas Elmqvist

([email protected])

– Edi Tudoreanu ([email protected])

– Philippas Tsigas ([email protected])