1. 9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Upper-Body Interactive Rehabilitation System for Children with Cerebral Palsy: The Effect of Control/Display Ratios
Takehiko Yamaguchi1, Paul Richard2, Fabienne Veaux3, Mickaël Dinomais4, Sylvie Nguyen5
1,2,3,4,5Laboratoire d'Ingénierie des Systèmes Automatisés, Université d’Angers, Angers, France
3,4Centre les Capucins, Département de Médecine Physique et de Rééducation Pédiatrique, Angers, France
4Faculté de Médecine; Département de Médecine Physique et de Réadaptation Pédiatrique, Université
d’Angers, Angers, France

2. Introduction Related Studies Proposed System System Evaluation
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Related Studies
Proposed System
System Evaluation
Results and Discussion
Conclusion

3. 9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Cerebral palsy (CP): various motor impairments caused by damage to the central nervous system during foetal development
It affects about 0.3% of births
(Krageloh-Mann, and Cans, 2009)
It often manifests itself during childhood
Physical therapy is need;
- Improve their movement patterns.
- Maintain the range of the affected arm/leg joints.
Constraint-induced movement therapy (CIMT)
It encourages the use of the
affected hand by restricting the
unaffected hand and asking for
intensive movement with the
impaired upper limb
Having the "good" arm blocked for long
periods of time can generate frustration
in the child
More "child-friendly" approaches are needed

4. 9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Traditional CP Therapy: is often of little interest to a child, affecting his motivation to continue such therapeutic activities (Schmidt, and Lee, 2005)
Traditional CP Therapy is not motivating and entertaining for child
Virtual Reality (VR): systems offer the capability to achieve rehabilitative goals through the use of real-time feedback and adaptive strategy/difficulty (Le Gal et al., 2008)
VR remains motivating and entertaining
Goal of project: is to develop a “child-friendly, motivating, and entertaining” rehabilitation system for children with CP

5. Motion capture based VR rehabilitation system using Kinect sensor
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Traditional CP Therapy: is often of little interest to a child, affecting his motivation to continue such therapeutic activities (Schmidt, and Lee, 2005)
Traditional CP Therapy is not motivating and entertaining for child
Virtual Reality (VR): systems offer the capability to achieve rehabilitative goals through the use of real-time feedback and adaptive strategy/difficulty (Le Gal et al., 2008)
VR remains motivating and entertaining
Motion capture based VR rehabilitation system using Kinect sensor

6. Related Studies Introduction Proposed System System Evaluation
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Related Studies
Proposed System
System Evaluation
Results and Discussion
Conclusion

7. 9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, FranceS eptember 10–12, 2012
Related Studies
IREX
EyeToy
Cybex Trazer
VR Rehabilitation ： Using full-body interaction via a tracking device
Working Space of Previous Systems： Visually limited since the user’s movement is directly projected on a screen via a tracking system
Limited working space could generate frustration on children’s motivation
Limit system capability: task variation, and interaction techniques for the rehabilitation task.
Concept of our system: Assist children with CP in a full-range of avatar movements to adapt the Control/Display (C/D) ratio of limb positions

8. 9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Related Studies
VR Rehabilitation ： Using full-body interaction via a tracking device
IREX
EyeToy
Cybex Trazer
Working Space of Previous Systems： Visually limited since the user’s movement is directly projected on a screen via a tracking system
Limited working space could generate frustration on children’s motivation
Limit system capability: task variation, and interaction techniques for the rehabilitation task.
Aim of this study: Explore the effectiveness of C/D ratios to analyze user performance,
work load, and user enjoyment

9. Proposed System Introduction Related Studies System Evaluation
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Related Studies
Proposed System
System Evaluation
Results and Discussion
Conclusion

10. Proposed System System Configuration A 60” TV monitor, A laptop
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Proposed System
System Configuration
A 60” TV monitor,
A laptop
A Microsoft Kinect sensor
A rehabilitation application running on the laptop
The application renders a visually-realistic 3D environment.

11. Proposed System VR Rehabilitation Application
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Proposed System
VR Rehabilitation Application

12. System Evaluation Introduction Related Studies Proposed system
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Related Studies
Proposed system
System Evaluation
Results and Discussion
Conclusion

13. System Evaluation Participants Apparatus 12 university students:
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
System Evaluation
Participants
12 university students:
9 male and 3 female,
between 19 and 30 years (M = 24.3, SD = 3.3 years)
Dominant hand: All participants were right-handed
Health: in good health,
Kinect experience: had not used a game using Kinect
All subjects were at a distance of about 3 meters from the Kinect sensor.
Apparatus
Kinect: one Kinect was used for training exercises and experimental tasks
FPS: Kinect was updated to about 20Hz
Platform: The Unity3D platform was used for graphic rendering
Monitor: 60 inch LG
PC: TOSHIBA laptop
OS: Windows 7
CPU: Intel Core i7 720QM processor
RAM: 4GB of memory

14. System Evaluation Task Procedure 1 session x 3 times
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
System Evaluation
Task Procedure
Training
Trial
Questionnaire
x 3 times
1 session
Independent variable: C/D ratio
Level: ratio 1.0, ratio 1.5, ratio 2.0

15. System Evaluation Task Procedure 1 session x 3 times Training
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
System Evaluation
Task Procedure
Training
Trial
Questionnaire
x 3 times
Independent variable: C/D ratio
Level: ratio 1.0, ratio 1.5, ratio 2.0
1 session
Training
20 – 40 objects were applied every 2 seconds
Randomly
between °

16. System Evaluation Task Procedure 1 session x 3 times Trial
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
System Evaluation
Task Procedure
Training
Trial
Questionnaire
x 3 times
1 session
Independent variable: C/D ratio
Level: ratio 1.0, ratio 1.5, ratio 2.0
Trial
60 objects
The applied direction : randomly selected out of 3 angles
60°
-5°
-40°
C/D 1.0

17. System Evaluation Task Procedure 1 session x 3 times Trial
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
System Evaluation
Task Procedure
Training
Trial
Questionnaire
x 3 times
1 session
Independent variable: C/D ratio
Level: ratio 1.0, ratio 1.5, ratio 2.0
Trial
60 objects
The applied direction : randomly selected out of 3 angles
60°
-5°
-40°
C/D 1.0
27.5°
125°
-25°
C/D 1.5
190°
-10°
60°
C/D 2.0

18. System Evaluation Task Procedure 1 session x 3 times Questionnaire
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
System Evaluation
Task Procedure
Training
Trial
Questionnaire
x 3 times
1 session
Independent variable: C/D ratio
Level: ratio 1.0, ratio 1.5, ratio 2.0
Questionnaire
Nasa TLX for workload
Physical Activity Enjoyment Scale (PACES) for Enjoyment of the training

19. Results and Discussion
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Related Studies
Proposed system
System evaluation
Results and Discussion
Conclusion

20. Results and Discussion
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Results and Discussion
Dependent variables
Performance data:
Take success rate
Subjective data:
Nasa TLX
Physical Activity Enjoyment Scale

21. Results and Discussion
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Results and Discussion
Task success rate
C/D 1.0 (M = 99.72% , SD = 0.96%) > C/D 2.0 (M = 90.28% , SD = 10.77%)
C/D 1.5 (M = 97.50% , SD = 3.51% ) > C/D 2.0 (M = 90.28% , SD = 10.77%)
C/D ratio was related to task difficulty
190°
-5°
-40°
60°
125°
-10°
-25°
27.5°
User comments

22. Results and Discussion
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Results and Discussion
Task success rate
C/D 1.0 (M = 99.72% , SD = 0.96%) > C/D 2.0 (M = 90.28% , SD = 10.77%)
C/D 1.5 (M = 97.50% , SD = 3.51% ) > C/D 2.0 (M = 90.28% , SD = 10.77%)
C/D ratio was related to task difficulty
User comments
60°
190°
60°
125°
27.5°
-5°
-10°
-25°
-40°
The user’s movement strategy for the task could be changed

23. Results and Discussion
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Results and Discussion
Nasa TLX
Temporal Demand (Significant trend):
C/D 2.0 (M = 3.67 , SD = 1.15) > C/D 1.0 (M = 2.67 , SD = 0.98)
Effort (Significant effect):
C/D 2.0 (M = 3.41 , SD = 1.24) > C/D 1.0 (M = 2.08, SD = 0.67)
Required to make an effort to complete a task with a C/D 2.0 ratio
There was time pressure with C/D 2.0 ratio
Concerning frustration:
Expected Result : Felt stress for avatar operations in C/D 1.5 and 2.0 ratio conditions
Result : No significant effect
comfortable operation for the C/D 2.0 ratio because of the speed of the avatar's movement.
uncomfortable operation for C/D 1.0 because the avatar’s movement was slow.
User comments

24. Results and Discussion
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Results and Discussion
Enjoyment
No significant effect
C/D 1.5 and 2.0 :
Could be challenged, excited, and motivated to perform the task
C/D 1.0 condition :
no excited, and no challenged , but the movement was realistic, natural, simulated
User comments
User motivation can be changed with different C/D ratios.

25. Conclusion Introduction Related Studies Proposed system
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Introduction
Related Studies
Proposed system
System evaluation
Results and Discussion
Conclusion

26. Conclusion Aim of this study Method Findings Future works
9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Conclusion
Aim of this study
Explored the effectiveness of C/D ratios in our prototype application
- Applied the object catching task with 3 kinds of C/D ratio to analyze user performance, work load, and user enjoyment with university students without motor impairments
Method
Performance data - Success rate:
C/D ratio was related to task difficulty
The user’s movement strategy for the task could be changed
Subjective data - Workload:
High C/D ratio could make an effort, and time pressure
High C/D ratio could make it comfortable on avatar movement
Low C/D ratio could make it uncomfortable on avatar movement
Subjective data - Enjoyment:
User motivation could be changed with different C/D ratios.
Findings
Different kinds of C/D ratios will be designed to better understand their effectiveness.
Other kinds of interaction techniques we have developed will be investigated using patients with impaired motor function.
Future works

27. 9th International Conference on Disability, Virtual Reality and Associated Technologies Laval, France September 10–12, 2012
Any questions?