thang010146 | Emergency chain ladder 1 @thang010146 | Uploaded 1 year ago | Updated 2 days ago
It is a suggested solution on request from Adaptive Concepts LLC Troy, Michigan USA working on a project with the University of North Carolina Natural Disaster Mitigation Team to reduce mass casualties from a tsunami event.
The user sits on the yellow saddle and pedals to lift himself up.
The chain (transparent red) wraps around the four orange sprockets. Its upper end is fixed to a fixed beam.
For more on the pedal mechanism see:
youtu.be/xkeALEAkIds
Pros: the mechanism is automatically blocked when pedaling is stopped.
Cons: can't pedal down.
To drop the ladder down for the next user: separate the blue pawls from the pink ratchet wheels using the brown cams.
Some calculations:
Sprocket radius R: 35 mm
Crank length L: 175 mm
Mechanical advantage: L/R = 5
Equipment weight: 10 KG
Weight of the user: M KG
Required pedaling force: (M+10)/5
1 double step makes the sprocket turn 1/6 rev.
1 double step lifts the user to: Pi*2*R/6 = 3.14*2*35 = 36.6 mm
Required lifting height: 30 m = 30,000 mm
Number of double steps required to lift the user to 30 m
30,000/36.6 = 820 steps
In 1 second the user can do 2 double steps
Time required to lift the user 30 m:
820 steps / 2 (steps/second) = 420 seconds = 7 minute
It is a suggested solution on request from Adaptive Concepts LLC Troy, Michigan USA working on a project with the University of North Carolina Natural Disaster Mitigation Team to reduce mass casualties from a tsunami event.
The user sits on the yellow saddle and pedals to lift himself up.
The chain (transparent red) wraps around the four orange sprockets. Its upper end is fixed to a fixed beam.
For more on the pedal mechanism see:
youtu.be/xkeALEAkIds
Pros: the mechanism is automatically blocked when pedaling is stopped.
Cons: can't pedal down.
To drop the ladder down for the next user: separate the blue pawls from the pink ratchet wheels using the brown cams.
Some calculations:
Sprocket radius R: 35 mm
Crank length L: 175 mm
Mechanical advantage: L/R = 5
Equipment weight: 10 KG
Weight of the user: M KG
Required pedaling force: (M+10)/5
1 double step makes the sprocket turn 1/6 rev.
1 double step lifts the user to: Pi*2*R/6 = 3.14*2*35 = 36.6 mm
Required lifting height: 30 m = 30,000 mm
Number of double steps required to lift the user to 30 m
30,000/36.6 = 820 steps
In 1 second the user can do 2 double steps
Time required to lift the user 30 m:
820 steps / 2 (steps/second) = 420 seconds = 7 minute
