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superfast (too fast?) electric scooters
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thm_w:

--- Quote from: Someone on April 28, 2023, 12:15:10 am ---"average" person is below that figure, while self selecting "fit" people would come in around there:
https://en.wikipedia.org/wiki/Human_power
Even young healthy males have trouble meeting 150W for an hour and that's operating to exhaustion:
"Effects of Differing Pedalling Speeds on the Power-Duration Relationship of High Intensity Cycle Ergometry." McNaughton & Thomas 1996
(people cycling for transport generally don't arrive unable to function)

--- End quote ---

The first wiki link is just someones estimate of "50-150W".
The second one is a good find, shows an infinite line at about 110W. So healthy 24y/o male could cycle easily at 110W for hours. 150W for an hour was the average failure point as you say.

Semi related one I found, power in trained males seemed to drop more with age vs women https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3794488/
Someone:

--- Quote from: thm_w on May 01, 2023, 10:59:07 pm ---
--- Quote from: Someone on April 28, 2023, 12:15:10 am ---
--- Quote from: thm_w on April 27, 2023, 11:25:32 pm ---25km/h on a flat road, is only 115W of output power. Its a bit hard to see that the average person can only output 115W for 1hr. But if you include sedentary individuals, you could be right.

--- End quote ---
"average" person is below that figure, while self selecting "fit" people would come in around there:
https://en.wikipedia.org/wiki/Human_power
Even young healthy males have trouble meeting 150W for an hour and that's operating to exhaustion:
"Effects of Differing Pedalling Speeds on the Power-Duration Relationship of High Intensity Cycle Ergometry." McNaughton & Thomas 1996
(people cycling for transport generally don't arrive unable to function)

--- End quote ---
The first wiki link is just someones estimate of "50-150W".
The second one is a good find, shows an infinite line at about 110W. So healthy 24y/o male could cycle easily at 110W for hours. 150W for an hour was the average failure point as you say.

Semi related one I found, power in trained males seemed to drop more with age vs women https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3794488/
--- End quote ---
exhaustion /= easily
also those figures and plots are extrapolated from a simple model that breaks down at longer (1h plus) durations so the numbers are not representative of longer durations or "infinity":
https://www.eevblog.com/forum/chat/a-possible-way-to-keep-your-fridge-cold-in-long-term-blackouts/msg4245910/#msg4245910
>100W for hours at a time is moving into amateur athlete territory. 100W in 1h is already way above "average" person, but do find some figures to support your claims.....
thm_w:

--- Quote from: Someone on May 02, 2023, 12:13:30 am ---exhaustion /= easily
also those figures and plots are extrapolated from a simple model that breaks down at longer (1h plus) durations so the numbers are not representative of longer durations or "infinity":
https://www.eevblog.com/forum/chat/a-possible-way-to-keep-your-fridge-cold-in-long-term-blackouts/msg4245910/#msg4245910
>100W for hours at a time is moving into amateur athlete territory. 100W in 1h is already way above "average" person, but do find some figures to support your claims.....

--- End quote ---

I'm sure you've experienced the same thing when running, hiking, working whatever. Push yourself a bit, find the point at which you start to progressively wear out, then dial it back. At that level you can go for many hours. You can verify this by looking at a power curve, where power output is recorded on all of your rides, then it gets mapped against time spent.

One example (super fit person, not average):

You can see the difference in power between 2 and 4h is minimal, maybe a few percent. Obviously we don't approach infinity, as we need sleep, but, maybe 5-10h until you see a drop.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5070974/
https://www.highnorth.co.uk/articles/critical-power-calculator
tom66:
A friend of mine pointed me to a website selling scooters with an output power (peak) of 8400W and a top speed of about 60 mph.  That particular scooter weighed 50kg.  With a 100kg rider, say, it has a total mass of 150kg, and a power-to-weight ratio of 56W per kg.

What else has a power to weight ratio in the same range?  The VW Golf 1.5 TSI (2022) with fuel and driver weighs about 1400kg and has an output power of 96kW peak.  That's about 68W per kg.

So this scooter has nearly the same power to weight ratio as a VW Golf, a vehicle for which you need insurance and a proper licence adminstered by a test facility to operate. Obviously, the collision damage risk for the Golf is far worse; I'm not doubting that.  But I've also little doubt that 30+ mph of 150kg scooter and rider hitting a pedestrian will also be fatal.

These vehicles are going to be used; the "cat is out of the bag".  It is up to the government to find appropriate regulations for them.   That will almost certainly include insurance, and possibly a basic competency test.   They'd better figure it out sooner, rather than later.
Someone:

--- Quote from: thm_w on May 02, 2023, 09:48:24 pm ---
--- Quote from: Someone on May 02, 2023, 12:13:30 am ---exhaustion /= easily
also those figures and plots are extrapolated from a simple model that breaks down at longer (1h plus) durations so the numbers are not representative of longer durations or "infinity":
https://www.eevblog.com/forum/chat/a-possible-way-to-keep-your-fridge-cold-in-long-term-blackouts/msg4245910/#msg4245910
>100W for hours at a time is moving into amateur athlete territory. 100W in 1h is already way above "average" person, but do find some figures to support your claims.....

--- End quote ---

I'm sure you've experienced the same thing when running, hiking, working whatever. Push yourself a bit, find the point at which you start to progressively wear out, then dial it back. At that level you can go for many hours. You can verify this by looking at a power curve, where power output is recorded on all of your rides, then it gets mapped against time spent.

One example (super fit person, not average):

You can see the difference in power between 2 and 4h is minimal, maybe a few percent. Obviously we don't approach infinity, as we need sleep, but, maybe 5-10h until you see a drop.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5070974/
https://www.highnorth.co.uk/articles/critical-power-calculator

--- End quote ---
You can keep pointing to data from athletes, but that does not link/match/inform data about average people. Every person is unique and has different limitations on their sustained power, the amateur trials that NASA modelled dropped 30-40% from 2hr to 4hr, 150W to 100W. Or you know instead of trying to extrapolate on highly variable human performance data, just go back to the actual question...

--- Quote from: thm_w on April 27, 2023, 11:25:32 pm ---
--- Quote from: Zero999 on April 27, 2023, 09:15:14 am ---That's the whole point: to limit the speed to what an average person can sustain for a decent period of time on an ordinary bike.
--- End quote ---
I can't find the justification for the laws but, it could also be a direct safety consideration. Above X speed injuries will be much worse.
But my point was it varies based on region. We've got UK 25km/h, Canada 32km/h, USA 32-45km/h. Is the UK one "right"?

25km/h on a flat road, is only 115W of output power. Its a bit hard to see that the average person can only output 115W for 1hr. But if you include sedentary individuals, you could be right.
--- End quote ---
To design road infrastructure the speed of the users is measured, average cyclists being somewhere around 15km/h (already a self selecting group, and not indicative of overall population average). Average bicycle speed sampled in real use 13.5km/h
https://journals.sagepub.com/doi/10.1177/1687814015616918
The histograms only have a few outliers above 25km/h, making the 25km/h limit seem pretty reasonable.
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