Elad Gefen presents his mechanical engineering design portfolio including projects completed during his BSc studies. The portfolio includes a CAD model of a bicycle gear derailleur created in SolidWorks with 37 parts and an exploded view. It also describes the development of a shopping bag handle including conceptualization, CAD modeling, FEA analysis, and prototype manufacturing. Another project involved FEA analysis of a plastic medical device enclosure to test for stresses from applied forces and drop tests. A fidget toy project covered managing a team through the entire product development cycle of market research, design, mold CNC, plastic flow modeling, and final production.
2. Before we start…
Welcome, and thank you for taking the
time to view my portfolio.
This portfolio presents some of the
many projects I completed during my
BSc studies.
I hope this gives you a better picture of
my skills and abilities.
Please feel free to contact me at
eladgfen@gmail.com with any
questions or to discuss my projects.
• Projects Index:
• Bicycle Gear Derailleur – CAD model
(SolidWorks)
• Shopping Bag Handle –
R&D/Manufacturing
• Finite Element Analysis (FEA) of Plastic
Medical Device Enclosure
• Fidget Toy – R&D/Manufacturing
3. Bicycle Gear Derailleur – CAD model (SolidWorks)
• Reverse engineering Solidworks CAD model of Shimano RD-TX35 bicycle derailleur
• 37 uniquely modeled parts
• Motion study with exploded view
• Multiple sub-assemblies created for design review purposes
4. Bicycle Gear Derailleur – CAD model (SolidWorks)
• Mechanism was taken apart
• Each part as outlined and measured for modelling
5. Bicycle Gear Derailleur – CAD model (SolidWorks)
• General dimension drawing, exploded view drawing, BOM (as required for project)
6. Shopping Bag Handle – R&D/Manufacturing
Full product development cycle:
• Conceptualization
• Mock-up and testing
• CAD model with FEA analysis
• Prototype manufacturing (3d printed body, cast aluminum core)
7. Shopping Bag Handle – R&D/Manufacturing
Conceptualization based on User Requirement Specification (URS)
8. Shopping Bag Handle – R&D/Manufacturing
Mock-up and Testing:
• Used card-stock layering and hand forming
based on ergonomic principles researched
• Ergonomics testing
• Usability testing
9. Shopping Bag Handle – R&D/Manufacturing
CAD model (SolidWorks):
• Core and symmetrical body
• Designed per Factor of Safety
(FOS) requirements (FOS < 1.6)
• FEA used to ensure FOS
10. Shopping Bag Handle – R&D/Manufacturing
Prototype manufactured:
• Ergonomic 3D printed body
• Lightweight cast aluminum core for strength
• Tested at 20kg with no bending of materials,
no shearing of connecting pins
11. Finite Element Analysis (FEA) of Plastic Medical Device Enclosure
• Force applied equal to approximate pressure
applied by users hand (~20 Newton)
• Analysis of enclosure snaps
• Drop test from various heights
12. Finite Element Analysis (FEA) of Plastic Medical Device Enclosure
• Mesh size chosen using Convergence on Point and
Convergence on Line analyses
0
1
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3
4
5
6
7
8
0 50000 100000 150000 200000 250000 300000 350000
SigmaMax
DOF
Convergence at Point, Sigma Max
(DOF)
0
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-50 -40 -30 -20 -10 0
Sigma[MPa}
X Coordinate
Line Convergence, Sigma (X)
Mesh 8
Mesh 6
Mesh 4
Mesh 3
Mesh 2
13. Finite Element Analysis (FEA) of Plastic Medical Device Enclosure
• Drop tests between 1 and 2 meter heights
• Drop test angle 31.02 degrees
• Maximum stresses located
• Snaps analysis for max stress and failure
14. Fidget Toy – R&D/Manufacturing
• Managed team of five; oversaw entire product
development cycle
• Manufactured using plastic injection molding
15. Fidget Toy – R&D/Manufacturing
• Development cycle included: market research,
ideation, iterative design, CAD, mold CNC, plastic
flow modelling, final production
16. Fidget Toy – R&D/Manufacturing
• Plastic flow analysis on individual parts and parts tree
• Analyzed parameters to optimize injection: material
temperatures, pressures, number of injection points,
injection locations
• FEA to find maximum yield strength for parts
undergoing bending
• Additionally analyzed for maximum deformation
17. Fidget Toy – R&D/Manufacturing
• Used SolidCam to generate GCODE for CNC machine
• Worked with CNC operator to mill mold
• Final production of product
• Poor moldings were analyzed for manufacturing
defects
• Injection parameters altered to produce perfect
examples
