automated animal board for positioning in ocular photography and imaging
DESCRIPTION
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. Glaucoma. - PowerPoint PPT PresentationTRANSCRIPT
Automated Animal Board for Positioning in Ocular
Photography and Imaging
Dhaval DesaiNathan Kleinhans
Holly LiskeLaura PiechuraKellen Sheedy
Client: B’Ann GabeltDepartment of Ophthalmology
Advisor: Wally Block, PhDDepartment of Biomedical Engineering
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
Normal Vision
National Eye Institute
Vision with Glaucoma
National Eye Institute
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
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.
Design Specification
• Automated or require minimal manual labor
• Support weights up to 50 lbs
• Rotate 30 degrees from horizontal in pitch and roll directions
Rotary Actuator Model
•Independent rotary actuators–Control pitch and roll
•Automated rotation
•Inclinometer to measure angular displacement
Rotary Actuator Model
Pros:• No center support of
plate required• Low center of gravity• Direct correlation to
handheld control
Cons:• Precision• Torque on actuators• Actuator cost
• Mechanical approach
• Tape runs through platform in both directions
• Relies on system of internal pulleys
• Small motor retrieves tape (normalizes)
Ticker-Tape Model
Ticker-Tape Model
Cons:• Manual• Normalizing may
decrease life in service
Pros:• Simple design• Easy to record
displacement• Inexpensive design
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
Linear Actuator ModelPros: • Automated design• Continuous motion
and fine adjustment capabilities
Cons:• Complicated design• Actuators and
inclinometers are expensive
Design Matrix
Criteria Rotator Ticker Tape
Linear Actuator
Accuracy 4 7 7
Maximum loads 6 4 9
Cost 2 8 5
Ease of Manufacturing
6 4 6
Prototype Life 7 4 8
Total 25 27 35
Future Work
• Final Design modifications
• Choose and order materials
• Build prototype
• Test
References
• Glaucoma Research Foundation. www.glaucoma.org
• National Glaucoma Research. American Health Assistance Foundation. www.ahaf.org
• Glaucoma Resource Guide. National Eye Institute. www.nei.nih.gov/health
Questions?