1. Dr. Gallimore10/18/20151 Cognitive Issues in VR Chapter 13 Wickens & Baker

2. Dr. Gallimore10/18/20152 Cognitive Issues n Perceiving n Understanding n Short term –Where am I, what do I see, where do I go, how? n Long term –What can I learn

3. Dr. Gallimore10/18/20153 5 Features of VE n 3-D vs 2-D viewing –3D more realistic and similar to how we view the real world. n Dynamic vs static display –E.G.. Movie may provide better understanding than static pictures of same information. n Closed-loop vs open-loop interaction –Closed-loop person has control over the aspects of the world. Active vs passive

4. Dr. Gallimore10/18/20154 5 Features of VE n Ego-referenced vs world reference –Ego vs exocentric view points. –Frame of reference. –Ego reference considered immersed in environment. n Multimodel interaction –Our interactions and learning in the real world is based on information input into multiple channels. »Vision, auditory, touch, kinesthetic feedback, gesture, etc...

5. Dr. Gallimore10/18/20155 5 Features of VE n Five elements are not independent n We don’t know what must be included n Research focuses on subsets of VE features because of difficulty of incorporating everything n What you need will depend on the purpose of the environment

6. Dr. Gallimore10/18/20156 Uses of VE n According to Wickens & Baker, there are four categories of tasks that VE systems are designed to serve n 1. On-line performance - manipulation in a remote environment. Issues include: –Closed loop performance –Situation awareness –Workload or cognitive effort

7. Dr. Gallimore10/18/20157 Uses of VE n 2. Off-line training and rehearsal - practice in forgiving environment. Issues include: –Transfer of training –How realistic must it be? n 3. On line comprehension - obtaining understanding, comprehending, insight of information. Issues include: –How should the information be modeled? –Will modeling choices affect understanding incorrectly?

8. Dr. Gallimore10/18/20158 Uses of VE n Off-line learning and knowledge acquisition- transfer knowledge to be employed later is different form (e.g. Education) –Does it improve understanding more than other methods. –How can deeper knowledge be taught in this environment?

9. Dr. Gallimore10/18/20159 Tasks in Ve’s n Human factors principles should be applied in the development of VE. Including analysis of user needs and tasks. n Wickens & baker discuss 6 tasks that may be performed in a VE. Searchnavigation Visual-motor couplingmanipulation Perception and inspectionlearning

10. Dr. Gallimore10/18/201510 Tasks in Ve’s: Search n Search - looking for information in a 3D world, database, image, etc. –Maps –Different frames of reference –Aids (cues) to help with search

11. Dr. Gallimore10/18/201511 Tasks in Ve’s: Navigation n Navigation –Where am I, where do I go? –Point to point vs smooth navigation –Travel metaphor (flight, walking, logarithmic) –Situation awareness –Control devices and ability to navigate »Stability of perceptual motor loop –Perceptual biases

12. Dr. Gallimore10/18/201512 Perceptual Bias n Humans use cues to distinguish locations and orientations of self and objects in their environments such as: –Regularly spaced texture, size, binocular cues, gradients, slant, optic flow, etc.. (Depth perception cues). –These cues need to be included in the environment, but designed cues may not provide accurate perception of object location. –Examples of two perceptual biases: »Virtual space effect »2D-3D effect

13. Dr. Gallimore10/18/201513 Perceptual Biases Cont. n Virtual space effect - bias in perceived location of objects because of display magnification ( wide field of view) or minification (narrow field of view). n 2D-3D effect - perceived rotation of vectors towards a plane that is more closely parallel to the viewing plane. (Under estimation of slant of a surface, figure 13-1).

14. Dr. Gallimore10/18/201514 Perceptual Biases Cont. n Research needs –What are the perceptual biases? –What designs or aids can we include to help users? –What tasks are affected?

15. Dr. Gallimore10/18/201515 Tasks in VE: Visual Motor Coupling n The VE system can introduce artifacts that interrupt visual-motor coupling (e.G..Reaching, turning the head and seeing update of visual scene). Five issues are: –Gain –Time delay –Order –Travel-view decoupling: direction of motion decoupled from direction of gaze –Field-of-view

16. Dr. Gallimore10/18/201516 Visual Motor Coupling: Gain n Gain setting on control input. –Low gain, need to move the input a great deal before change occurs. –High gain, small input, large change or displacement. (Can lead to instability of control). –Appropriate gain settings will depend on input device and task. »Example space ball rotation vs translation

17. Dr. Gallimore10/18/201517 Visual Motor Coupling: Time Delay n Time delays or lags in updating the VE. –Flight simulation shows that 50 ms can impact performance. –May also effect spatial sensory reflexes (VOR). –To reduce time delays consider: »processing required due to complexity of images »adaptive or progressive imagery (simplified views) »predictive filtering of user input »research is still needed

18. Dr. Gallimore10/18/201518 Visual Motor Coupling: Control Order n System state - Task Dependent –zero order - position control –First-order - constant rate of change »use when navigation for movement to locations

19. Dr. Gallimore10/18/201519 Visual Motor Coupling:Travel View Decoupling n Direction of movement of travel, decoupled from direction of gaze. –Difficult to accomplish, especially with system lags –May cause disorientation –Needs research

20. Dr. Gallimore10/18/201520 Visual Motor Coupling: Field of View n Field of view Vs viewing angle –Field of view - how much of the field we can see at once (Instantaneous, without moving head). –Viewing angle is width subtended by a display. –Field of regard - with limited field of view can rotate our head and get larger field of regard. –Real world: viewing angle = field of view –VE can increase field of view as viewing angle is held constant (wide field of view, minification) or decrease field of view (magnification)

21. Dr. Gallimore10/18/201521 Visual Motor Coupling: Field of View n If use wider field of view: –see more information in the scene at once, may help with situation awareness –distort perceived location of objects –produced compelling sense of forward motion –may result in greater mismatch between motion and vestibular inputs

22. Dr. Gallimore10/18/201522 Tasks in VE: Manipulation n Issues for manipulating objects are similar to those for Navigation and Visual Motor Coupling –gain, time lag, control order, depiction of location and orientation, frame of reference –also consider feedback (force or auditory)

23. Dr. Gallimore10/18/201523 Tasks in VE : Perception and Inspection n Features need for this task may be different than those needed for Navigation. –What is needed is task dependent »May not need large amount of visual realism

24. Dr. Gallimore10/18/201524 Tasks in VE:Learning n Procedural training –how much realism do we need? –Active participation more important than realism n Perceptual motor skill learning –active control –sensory feedback n Spatial learning and navigational rehearsal –ability to build mental maps n Conceptual learning (understanding phenomenon) –active exploration –alternative knowledge representations

25. Dr. Gallimore10/18/201525 Effort and Workload n The VE could increase rather than workload. Need to evaluate the design. If interacting in the world becomes the primary task that diminishes the purpose, it may not be worth it. n Forcing more effort to understanding relationships can at times be beneficial to learning.