Engineered Components
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Transcript of Engineered Components
Engineered Components
Steering system Plate End cap Positioning rings Stabilizers String Placement
Suction and lubrication systems Drill Stand
Problem Definition
Drill a curved hole through the spine Used for medical procedures
i.e. spinal surgery, hip replacement, bone screws
Improved patient recovery time Less invasive anterior and posterior
approaches Increased mobility
Objectives Angle of approach equal to 45° Hole diameter of 5.5 – 7 millimeters
Definition of Scoliosis
Condition that involves complex lateral and rotational curvature of the spine Congenital – anomalies
present at birth Idiopathic – occurs during
lifetime Developed from other
symptoms
Current Scoliosis Treatments
Bracing is recommended when initial curve magnitude is between 20% and 40% Reduction of curvature between 25 and
35 degrees Negative side effects of discomfort and
psychological anguish Surgical procedure involving screws and
inserting metal rods to straighten the spine Time consuming with a six month recovery
time
Budget
Item Proposed ($) Spent ($) Difference ($)Rotary Drill Bit 20 20.02 -0.02
Flexible Shaft 30 58.97 -28.97Casing 100 22.24 77.76
Power System 50 98.97 -48.97Experiment Budget 1000 295.04 704.96
Total 1200 495.24 704.76
Technical Approach
Procedures Three phases performed concurrently Design phase – design components Build phase – assemble drill and
model spine Test phase – drill curved hole in spine
Milestones Progress Report, Student Expo
Presentation, Poster Presentation, Final Report, Delivery of Prototype
Gantt Chart
Prototype Components
Suction and Lubrication System
Current Drill Prototype
Plate steering system Three strings Angle of strings to shaft: 15° , 30° , 45° ,
60° Cutting Head
Carbide burr
Drill Stand
Concept drawing Designed to hold drill
during surgical procedure
To minimize number of hands needed to complete procedure
Placed on operating room tray
3-Phase Drilling
Phase 1 Insertion into vertebrae
Phase 2 Navigating the bend
Phase 3 Directed drilling
Material Testing
Drilled curved hole Point- and Push-the-Bit Compound curve
Model Spine 2:1 scale Represents layersof bone
Deflection Testing
Deflection Angle (°) Ave
Mass (kg) Weight (N) Trial 1 Trial 2 Trial 3 Angle (°)1 9.81 10 6 5 72 19.62 24 14 16 183 29.43 33.5 24 25 27.54 39.24 34 32 41 35.675 49.05 42.5 37 45 41.5
Horizontal Position (mm) Vertical Position (mm)
Mass (kg)x-
coordinatey-
coordinate Mass (kg)x-
coordinatey-
coordinate
0 0 0 0 0 0
1 7 -0.5 1 4 0
1.5 9 -1 1.5 11 -2
2.4 15 -4 2.4 20 -6.5
4.6 32 -10 3.5 33.5 -12
Deflection Results
0 5 10 15 20 25 30 35
-12
-10
-8
-6
-4
-2
0f(x) = − 0.336978810663021 x + 1.14593301435407R² = 0.960292217669766
Position of Cutting Head
Y-coordinate (mm)
X-c
oord
inate
(m
m)
0 5 10 15 20 25 30 35 40
-14
-12
-10
-8
-6
-4
-2
0f(x) = − 0.378953940066593 x + 1.09166897891232R² = 0.97468237974755
Position of Cutting Head (ver-tical set-up)
Y-coordinate (mm)
X-c
oord
inate
(m
m)
Progress Challenges
Unexpected Technical Challenges Drilling through plaster Completing surgical procedure in one
phase Keeping drill level Keeping tension in the strings Modeling drill tip using mathematical
equations
Deliverables
Written technical progress report Delivered [12/12/06]
Final drill prototype [5/7/07]
Test model with drilled holes [5/7/07]
List of further recommendations [5/7/07]
Drawings and prints for future assembly (CD format)
[5/7/07]
Written final report [5/7/07]