Personal Mobility Lift
2006-2007 Capstone
Team Members:
Jim Folgate
Bill Beers
Ryan Pelton
David Zuercher
Introduction
PDS
Concept Selection
Design Selections
Analysis
Fabrication
Verification
Additions
Product Design
Specifications
Mission Statement:
This project requires the team to design and build a
small functional device that will lift a person from the
floor (2”) to the height of a wheelchair or walker (24”30”.) The device will be firmly mounted to a wall, and
be powered by the person being lifted. This product
will be designed for anyone requiring the additional
mobility afforded by such a device.
High Priority Requirements
Lifting Range
Lowers Easily and
Safely
Human Powered
Secure Mounting
Ergonomic/Comfort
Maintenance Free
Long Wearing Finish
Cost
Concept Selection
Weight
Hand winch
Hydraulic
Scissor
Performance
3
2
5
2
Ergonomics
2
3
3
3
Quality/Reliability
3
4
4
5
Safety
3
3
4
3
Aesthetics
1
2
4
4
Cost
2
4
2
3
43
53
46
Totals
Ratchet
Detail Design Decisions
Bottle Jack
–
–
–
–
Inexpensive $10
Functional
Lifting Power
Built in features
Pump
Release valve
Scissor Lift
– Number of Linkages
– Lengths
– Beam analysis
Fasteners
– Diameters selected for
strength
– Lengths selected
based on design
geometry
Bushing Blocks
– Bronze Bushing
– Steel mounting
Guide Rods
– Solid Steel Shafts
– Precision machined
Frame
– 3/16” A36 Steel
– Doubles as the housing for
the lifting device, and a
supportive back for the
chair
Pump Handle
– Steel pipe with bungee
cord
Powder Coat
Analysis
FEA analysis of frame
Beam Analysis for the
Scissor members
Lateral Forces on the
Guide rods
Fastener Shearing
Analysis
Fabrication at Warn Industries
Assembly
Verification
Lifting Range
–
Lifts from 1/2” to 28”
Human Powered
–
Check
Secure Mounting
–
Mounted to wall studs
and flooring
Ergonomics
–
–
Smooth pumping action
Pillow-top seat (add-on)
Lowers easily and safely
– Controlled by the release
valve of the jack
Long wearing finish
– Powder Coat
Maintenance Free
– No required maintenance
Cost
– Final Prototype Cost $165
Lifting Capacity
– PDS requirement not met
New Additions
Some unpredicted motion of the chair has
cause the team to redesign and add a
guide block and bearings to the design.
The bearings will be attached to the
centerline of bolts on the scissor members
and will ride up a vertical block to stabilize
the vertical motion of the lift.
Questions