1. Neck Extender/Flexor for Fluoroscopy Examination
Client: Victor Haughton, M.D.
Advisor: Naomi Chesler, Ph.D.
Alison Boumeester
Vidhya Raju
Susan Samreth
Peter Strohm

2. Overview Problem Statement Background Information
Product Design Specifications
Design Alternatives
Decision Matrix
Future Work

3. Problem Statement Create neck positioner for use in fluoroscopy
Accommodate comatose patient

4. Background Information
Cervical Spine
Determine disk health through neck movement
Fluoroscopy
X-ray imaging in motion
Metal not desirable in imaging areas
Non-motorized device created Spring 2006

5. Product Design Specifications
Must not induce neck injuries
Motorized to prevent human error
Simulate natural neck movement
Extension/flexion to 45˚
from neutral
Rate of rotation 1˚/sec
Remote control operation
Neck Extension
Neck Flexion

6. Motor & Gear Design Bi-directional motor runs minor gear
Minor gear rotates planetary gear guide
Extension/ flexion centered about axis

7. Motor & Gear Design Cons Pros Gear must always support head board
Limited potential for expanding rotation range
Awkward shape
Mechanically complex
Pros
Easy assembly
No obstruction for lateral imaging
Achieves desired range of rotation
Realistic (anatomic) center of rotation
Components beneath table

8. Gear Actuator Design Motorized worm gear controls shaft elevation
Pins stabilize shaft, prevent rotation
Head board supported by roller guide

9. Gear Actuator Design Cons Pros Frame limits lower rotation range
Possible interference
Mechanically complex
Pros
Easy assembly
No obstruction for lateral imaging
Achieves desired range of rotation
Realistic (anatomic) center of rotation
Components beneath table

10. Linear Actuator Design
S-shaped board on table
Movement from actuator
Speed of rotation altered by adjusting voltage
power supply
AC to DC signal conversion

11. Linear Actuator Design
Pros
Easily constructed
No obstruction of lateral imaging
Achieves desired range of motion
Easily powered
Cons
Moments will occur at base of actuator
Base of actuator much lower than table
Rotational rate will vary

12. Design Matrix 100 86 68 71 Criteria Weights Linear Actuator Worm Gear
Gear and Motor
Safety 30 25 27 22
Feasibility 40 39 20
Aesthetics 10 6 9
Mechanics 16 15
Totals
100 86 68 71

13. Future Work Research linear actuators/power supplies
How to modify linear actuators
Research materials that will not
interfere with radiographic imaging
How to machine these materials
Prototype design

14. Acknowledgements Professor Block, Department of Biomedical Engineering
Professor Fronczak, Department of Mechanical Engineering
Professor Ranallo, Department of Radiology

15. Questions?