Re: Bike tech idea for Jeff

On 1/23/2025 9:05 PM, AMuzi wrote:

On 1/23/2025 7:55 PM, Jeff Liebermann wrote:

On Thu, 23 Jan 2025 17:38:20 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:
>

A sling of firewood is not a light load.  I just weighed it at 30 lbs.
When green, it's about 40 lbs.

>
<https://photos.app.goo.gl/rmqqcZ4g8h6mGg7v6>
>

 Nice photo. THX.
Any reason you couldn't carry less but more frequently?

I'll note that whatever Jeff weighs, he's got to haul his own weight upstairs every time me makes a trip. That argues for minimizing those trips.
To get 60 pounds of firewood lifted 35 feet, a 175 pound man carrying one pound per trip would do 370,000 ft*lbs of work against gravity, which is mostly just repeatedly lifting his body mass. If he were able to carry the 60 pounds of wood in one trip, his work against gravity would be just 8200 ft*lbs, mostly because his body mass is lifted only once.
But human power output is not simple. Carrying 60 pounds might be impossible. Still, it seems there's some optimum size for the load.
Normally the best approach would be to avoid lifting the body mass. Jeff wants exercise, but if we could work out a practical lift device, he could consider getting exercise some other way.
--
- Frank Krygowski