Does anyone know of a site/page that describes humanoid arm lengths, leg lengths, torso dimensions, etc., as ratios ? In other words, I'm looking for something that would give a rough roadmap of humanoid proportions so that it could be easily scaled to any size.
Something that describes simple anatomy in terms of mechanics might fit the bill, too.
The kind of information you are looking for is commonly presented in books about drawing the human figure. Try a search on the terms; human proportions draw. If you need to narrow it down, add terms which are parts of the body.
What the others have said. You can also find this information at any sewing pattern site, for typical male or female proportions. The ones that cater to self-designers have calculators for adjusting size.
But why humnanoid? We're not the most efficient biped on the earth. If I were to do something like this I think I'd model it after an orangutan (not a true biped but capable of it), or something.
I've been thinking the same... A few artist friends helped me on a design for a biped robot... They hadn't ever seen any other biped robots, and the design came out looking more orangutan looking than human.. It never got off paper, but it would have been much easier to balance and move the thing (than making it humanoid)
The original design was in laser cut plate, all I had to work with at the time and I couldn't fit it all in where it got skinny, particularly the ankle and the forearm so I gave up. I know have 2.5D CNC and I've come back to it, but it's not easy finding the time and I've got a lot more AutoCadding to do before I start cutting metal.
I haven't figured out the articulation at the base of the rib cage. It's a power movement (I differentiate power and gesture) and there isn't a lot of room for it because motors don't squidge out of the way like intestines so the lower abdomen is mostly off limits.
I'm also trying to design feet. You can extend the foot through the Achilles, you can rotate it at the ankle, then there's the twist. The twist has to be powered from inside the foot unless you want to start messing with universal couplings which makes the ankle fat. The toes twist a lot further than the heel when you turn an ankle so the pivot point has to be inclined. The pivot turns with the foot when you extend it but it's movement becomes increasingly restricted. I think this pivot has to move and align the toes with the ground as the weight rolls forward off the heel, and then lock either due to weight falling on the toes, or due to the extension of the foot. The final twist just before it leaves the ground can be achieved at the ankle. Probably. It's so hard to see what's actually happening, heaven knows I have tried :o)
Then there's the toes. Only one really counts, the rest vaguely follow it. The big toe can draw power from the foot extension and become part of it for gait. It also a screw drive, sprung to allow some flex and gesture but mainly providing a moveable stop that puts a hard limit on upward movement so it can contribute to static balance.
You've probably guessed I don't get to talk about this stuff much.
IMO even more reason to not model it after a human! An orangutan, as an example, can lift a car motor. It can walk on its hind legs, but it has the option of walking on all four legs, because its front legs are so long.
The only thing keeping the higher primates from taking over the world is their brains, not their bodies. Their bodies are better suited to manual labor than hours.
Hmmmm...apes taking over the world. Sounds like a neat concept for a movie, doesn't it?
There's a difference between human and humanoid in form. Many of the great apes are humanoid in form, though technically they are referred to as hominid. In the late 50s and early 60s NASA used chimps for environmental training - and even the first flight - in the very same capsules they used for the Mercury program. I think all they added was a booster seat. The chimps could be trained to flip switches if they needed to (they didn't need to as it was all automatic).
About the only thing to consider is leg length to reach a pedal. Easy to overcome, as any little old lady driving a Honda Civic will attest.
Ah, but as Gordon points out, you don't have to be humanoid in form just to operate equipment meant for humans. There are no doubt many options which are far better than the form of a human.
Lets say we have advanced AI technology to allow our machine to be as intelligent as a human (or more intelligent), and advanced enough to learn on its own how to operate any sort of appendage, or sensor, or effector we wanted to give it. In other words, what if programming complex dynamics of behavior were no long the issue. So, if we wanted it to hop on one foot, it would learn to do it as long as we gave it enough power to do it (or enough spring).
Given that type of control logic power, what form might we actually build machines which were meant to be general assistants for humans (could drive our cars for us, go to the store and shop for us, cut our grass for us, cook for us in a kitchen made for a human, clean for us with tools meant for use by a human, etc)?
Of course if such technology was available, we would see a whole range of robots of different sizes, shapes, and costs optimized for different tasks. But ignoring that, what generic form might we see develop for a general helper-bot which was designed so it could operate all typical human tools? Maybe it would be something more like the Octavius AI-arms from Spiderman where it was nothing more than 6 very flexible arms each with hands and eyes with only a very small central body? What other odd forms might they be built in?
Seriously, it does make more sense than I initially thought. For example, during those times when the bot is not doing any work, why waste power on maintaining balance when it can just drop down on all fours? But I absolutely refuse to give my robot a tail! On the other hand ... that might come in handy ...
When humans deviate from the norm, life becomes awkward. Humans don't have to deviate very far before parts of their environment have to be adapted so they can cope. Any deviation to gain an advantage in our ergonomic world will prove a handicap somewhere else, you will have made a cripplebot. My wife is 5 foot 2, the house is immaculate except for the cooker hood which gathers dust, she can't see it. With the benefit of my extra 10 inches I view it as a small oasis of reality in an artificially sterile world.
Also, I'm getting old, want to play now, not enough time left to wait for some future technology. I found the femoral length to be the determining factor for the overall height. Not because the levers are too long but because it's hard to make it short and fit everything in. You can't just bung in an RC servo when you want over 20 ft.lbf torque and some degree of alacrity :o)
Perhaps my problem is that I'm an engineer who loves designing lever systems. I see the human form as a fascinating design constraint which makes it fun to do. Each to his own I guess :o)
The constraint here is not mechanical but economics. Many of the machines humans operate inside of can themselves be automated. If you're going to spend the time and money on a human-like robot to operate a fork lift, you would have long exceeded the budget had you just automated the fork lift. (And in fact, they have those.)
Robots that work *around* humans and human-oriented machines are a different matter, and in that case, it makes much less sense to insist on strict humanoid proportions because they simply are not the best suited for most manual labor tasks. Example: On a human the strongest limbs are the legs, for running (after something, away from something).
OTOH, higher order primates like the arangutan have short stocky legs because running isn't that critical, but arms powerful enough to rip a person in two. Or more costructively, lift boxes or tools or lumber or merchandise. THAT is the kind of strength that would be useful in a work setting, don't you agree?