Stair Caddy Carries items up to 50 lbs up and downstairs 2.009 Blue - - PowerPoint PPT Presentation

Stair Caddy

2.009 Blue B Carries items up to 50 lbs up and downstairs

Sketch Model Review

Stair Caddy Design

For the 36+ million senior citizens

Existing Products

AATA International SR 450 AATA International SR 1750

Comparison

SR 450 SR 1750 Stair Caddy Mass of Cart 49 kg 175 kg 25kg Power 375 W 500 W 400 W Battery Life 3.5 hours 3.5 hours 5 hours Speed .15 m/s (7.9 in/s) .05 m/s (5.9 in/s) .31 m/s (12 in/s)

Testing for Consumer Needs

n Safety - Slip n Not ruining floor

material

n Items not falling out n Items not squished n Storage

Other Issues Learned

n Need more testing with treads n Turning Radius n Force applied to handle n Safety n Storage Size n Driving

Downstairs

Appendices

Additional Calculations

Total Steps 50 Steps Total Operation Time 50 sec Mass of Front Treads 3 kg Ang Speed .5 rad/sec (~30 deg/sec) Coefficient of Friction of Floor .3-.5 Motor Torque for Main Treads 20 Nm

Size

30” 30”

Staircase

Narrow Staircase 3 Contact Points

Stair Data

n Building Codes (Public Areas)

¡ Tread length: 9” ¡ Riser: 8.25”

n Measurements (Residential)

¡ Tread length: 7” ¡ Riser: 8”