1. Automated Animal Board for Positioning in Ocular Photography and Imaging
Dhaval Desai
Nathan Kleinhans
Holly Liske
Laura Piechura
Kellen Sheedy
Client: B’Ann Gabelt
Department of Ophthalmology
Advisor: Wally Block, PhD
Department of Biomedical Engineering

2. Glaucoma High intraocular pressure
Damage of the nerve fibers and the optic disc
Result: Vision loss
Current cure: None
Second leading cause of blindness in the world

3. Normal Vision
National Eye Institute

4. Vision with Glaucoma
National Eye Institute

5. Motivation Aim 1: Early diagnosis of glaucoma
Nerve fiber layer thickness
Normal vs. glaucoma
Aim 2: Explore treatment options
Chemotherapeutics and gene therapy
Animal model: Monkey
Monitor nerve fiber layer parameters at several time points

6. Problem Statement
Fine adjustments in the positioning of the eye are necessary to obtain quality images of the retina and nerve for glaucoma research. The goal of this project is to construct an automated positioning device that provides accurate alignment of the animal for successive scans.

7. Design Specification Automated or require minimal manual labor
Support weights up to 50 lbs
Rotate 30 degrees from horizontal in pitch and roll directions

8. Rotary Actuator Model Independent rotary actuators Automated rotation
Control pitch and roll
Automated rotation
Inclinometer to measure angular displacement

9. Rotary Actuator Model Pros: Cons: No center support of plate required
Low center of gravity
Direct correlation to handheld control
Cons:
Precision
Torque on actuators
Actuator cost

10. Ticker-Tape Model Mechanical approach
Tape runs through platform in both directions
Relies on system of internal pulleys
Small motor retrieves tape (normalizes)

11. Ticker-Tape Model Cons: Pros: Manual Simple design
Normalizing may decrease life in service
Pros:
Simple design
Easy to record displacement
Inexpensive design

12. Linear Actuator Model Employs two electric linear actuators
Ball and socket heads are mounted to actuators
Central ball and socket column
Inclinometer to measure angular displacement

13. Linear Actuator Model Pros: Cons: Automated design Complicated design
Continuous motion and fine adjustment capabilities
Cons:
Complicated design
Actuators and inclinometers are expensive

14. Design Matrix Criteria Rotator Ticker Tape Linear Actuator Total 25 27
Accuracy 4 7
Maximum loads 6 9
Cost 2 8 5
Ease of Manufacturing
Prototype Life
Total 25 27 35

15. Future Work Final Design modifications Choose and order materials
Build prototype
Test

16. References Glaucoma Research Foundation. www.glaucoma.org
National Glaucoma Research. American Health Assistance Foundation.
Glaucoma Resource Guide. National Eye Institute.

17. Questions?