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CrankGPT

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Re: CrankGPT

#141

Post by rirze »

rahimnathwani wrote: post #127
eks391 wrote: post #84

Earlier quoted context omitted.

I took several biomechanics classes as electives back in my undergrad, and in one assignment I remember comparing the energy outputs between the human and robot equivalents of different tasks, whether or not the robot was humanoid in how it was designed. The most impressive think that stuck with me is that humans are incredibly efficient , from an energy perspective, in anything we do, compared to machines. Every tim…

"Every time we delegate a task to a machine, we are using several orders of magnitude of energy to do the same thing." Might this just be selection bias? I mean, if humans can't do a task efficiently, we're not going to do the comparison with a machine. Some actions we do seem (to me) very inefficient when compared with machines. For example: grating carrots and brushing teeth.

There's a difference between consistency and efficiency.

I read efficiency as "Energy inputted to accomplish a task", in which case, biological systems are far more efficient than current-day mechanical ones. It's a tradeoff.

Re: CrankGPT

#142

Post by layer8 »

eks391 wrote: post #84
meindnoch wrote: post #24

Earlier quoted context omitted.

For reference, this is what 700W cycling looks like: https://www.youtube.com/watch?v=S4O5voOCqAQ

I took several biomechanics classes as electives back in my undergrad, and in one assignment I remember comparing the energy outputs between the human and robot equivalents of different tasks, whether or not the robot was humanoid in how it was designed. The most impressive think that stuck with me is that humans are incredibly efficient , from an energy perspective, in anything we do, compared to machines. Every tim…

Unfortunately, humans want houses and cars and vacations and such, which makes them very expensive. ;)

Re: CrankGPT

#143

Post by malfist »

kccqzy wrote: post #119
kowbell wrote: post #88

Earlier quoted context omitted.

As an average male who is ~175lbs and untrained at cycling, this is hugely validating for my terrible idea; 140 watts is the max charging speed for 16" M5 MacBooks. I can finally stop thinking for myself and have my computer do it all for me, powered by my big beefy legs.

140 watts is the FTP. That means you can do it for an hour, and it will be an extremely exhausting hour and you will want at least two days of rest to recover from this workout before doing it again. If you are not chasing watts, it’s much more sustainable to do 70 watts for two hours. You can probably do this every day.

This exactly. FTP is functional threshold power, it's the maximum you can physically maintain in zone 4 heart rate for 40-60 minutes and it's physically exhausting. This is hard work, hardest work honestly. If you have gas left in the tank after you could had a higher FTP. I'll get out on the bike and do a zone 4 workout and keep a steady state of 180-200 watts through the first 20-30 minutes, by the end of the hour or hour and a half of my workout, even with breaks to break, reset heart rate, have some water, salt and glucose, I'm down to 120-150 watts at the end of the ride.

Basically, you can probably charge your macbook at peek power for an hour every other day, or every day for a short while if you're okay with burning out eventually.

Expect to need to eat 400-600 calories and a lot of water each time you do this.

Re: CrankGPT

#144

Post by xnx »

SoftTalker wrote: post #118
thewebguyd wrote: post #57

Earlier quoted context omitted.

For more reference how insane 700W is, the average FTP of a world tour pro road cyclist (i.e., Tour de France) is ~350-420W/6-7W/kg. FTP (Functional Threshold Power) being the avg you can sustain for an hour without fatiguing. My own is ~250W @ 3.12W/kg. I can't even hit 700W yet, let alone for over a minute. My 5 second power is ~640W. Crazy numbers.

A trained powerlifter probably exerts a few kW on a heavy lift, but only for a second or two.

~3000 watts for 0.75 seconds (not counting pauses)

Re: CrankGPT

#146

Post by codazoda »

kowbell wrote: post #9

My partner just got a rowing machine that offered "watts" as a unit of how hard you're going (like "calories" or "mph") and got me wondering if they made rowing machines that could slowly charge a battery, and how much I'd need to row to power one of them fancy newfangled M5 Max MacBooks answering prompts. All that to say, CrankGPT, I am your target demographic and if you don't respond to my request for a demo I'll b…

[dead]

Re: CrankGPT

#147

Post by vitally3643 »

rahimnathwani wrote: post #127
eks391 wrote: post #84

Earlier quoted context omitted.

I took several biomechanics classes as electives back in my undergrad, and in one assignment I remember comparing the energy outputs between the human and robot equivalents of different tasks, whether or not the robot was humanoid in how it was designed. The most impressive think that stuck with me is that humans are incredibly efficient , from an energy perspective, in anything we do, compared to machines. Every tim…

"Every time we delegate a task to a machine, we are using several orders of magnitude of energy to do the same thing." Might this just be selection bias? I mean, if humans can't do a task efficiently, we're not going to do the comparison with a machine. Some actions we do seem (to me) very inefficient when compared with machines. For example: grating carrots and brushing teeth.

No, it's evolution. Mammals burn a ridiculous amount of energy just existing, so evolutionary pressures tend toward more efficient muscles and body geometry.

Electrochemical reactions in your muscles combined with the mechanical advantage from the geometry of your joints and ligaments is simply more energy efficient than most mechanical or electromechanical systems. On top of that, our learned and evolved kinematic algorithms result in vastly more efficient control. Humans tend to be pretty good at using only exactly as much energy as required for a given action. Overshoot is quite limited compared to robots.

Your suggested actions seem inefficient, but if you look at the actual energy expenditure, mechanical means are much worse simply because mammalian muscle is so efficient.

Re: CrankGPT

#149

Post by pants2 »

eks391 wrote: post #84
meindnoch wrote: post #24

Earlier quoted context omitted.

For reference, this is what 700W cycling looks like: https://www.youtube.com/watch?v=S4O5voOCqAQ

I took several biomechanics classes as electives back in my undergrad, and in one assignment I remember comparing the energy outputs between the human and robot equivalents of different tasks, whether or not the robot was humanoid in how it was designed. The most impressive think that stuck with me is that humans are incredibly efficient , from an energy perspective, in anything we do, compared to machines. Every tim…

If you're comparing raw calories to output, yes. Even gasoline has a caloric value, but humans can't drink gasoline. Growing and preparing food for human consumption uses a lot more energy than pumping and refining gasoline, so at the end of the day, human efficiency gains are not that impressive.

Re: CrankGPT

#150

Post by bko »

jszymborski wrote: post #135
bko wrote: post #117

Earlier quoted context omitted.

Or we could... hear me out... build more power plants. The de-growth stuff is pretty evil when you take it to it's logical conclusion of population control.

There's a bit of a difference between population control and reaching a sustainable equilibrium. One can also argue the death of all life on earth is a pretty evil logical conclusion of infinite growth on a finite planet.

What does "sustainable equilibrium" mean?

What are you balancing if not human growth? And how do you plan to do that?

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