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
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
Analysis FEA analysis of frame Beam Analysis for the Scissor members Lateral Forces on the Guide rods Fastener Shearing Analysis
Fabrication at Warn Industries
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 maintenanceCost –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.