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Show HN: Sketch, connect and simulate gears and chains

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Re: Show HN: Sketch, connect and simulate gears and chains

#51

Post by hamburglar »

Sunlis wrote: post #12

Great for touchscreen, but tricky with a mouse. I would like to see an option for drawing gears where mouse down sets the center of a new gear and dragging away determines the radius.

Agreed, and some controls that allow you to specify the radius of a gear instead of drawing it would help, too. I spent a long time trying to draw two gears with the same number of teeth on my ^#$(@#! trackpad. :)

Also, there's a UI limitation with snapping concentric gears together: you can snap a small gear onto a larger one, but not the other way around. This seems to make it impossible to add a pair of concentric gears whose smaller gear is meshed with the edge of an existing gear.

But overall, great project with very pleasant casual interaction. Would be interesting to see what you plan to do with it.

Re: Show HN: Sketch, connect and simulate gears and chains

#53

Post by acomjean »

reminds me of Arthur Ganson, artist who sometimes makes homemade gears. Has fun with gear ratios too (I think the machine with concrete will spin 1 revolution in 10000yrs if I remember correctly).

http://www.arthurganson.com/pages/Sculptures.html

I was a museum gaurd at an art museum that had his work last century. He now has a permanent home at the MIT Museum.

Re: Show HN: Sketch, connect and simulate gears and chains

#54

Post by lifeformed »

bmelton wrote: post #41
lifeformed wrote: post #27

Earlier quoted context omitted.

Hmm... maybe there are more common sources of strong-but-slow power. The heat expansion of bridges? The weight of vehicles sitting idly at a stoplight? The swaying of skyscrapers? I wonder if you could make a purely mechanical solar panel that way. Get a giant sheet of metal, put it out in the sun, and attach this gear arrangement to it, braced by opposite sides of the expansion. Hmm... I kinda want to make this now.

What you're describing is a move up the Kardashev scale[1]. The Kardashev scale measures how tech-savvy a society is by how they collect and use energy. A Type I society on the scale is able to harness and store all the energy generated on the planet, which we're moving towards now. Regenerative braking and such are definitely progressions in that area, but presumably bigger gains could be had by harnessing the power…

I wonder if we'll be able to harvest all ambient sound one day.

Re: Show HN: Sketch, connect and simulate gears and chains

#55

Post by pfraze »

jameshart wrote: post #48
lifeformed wrote: post #22

I've always wondered - Consider the following gear arrangement: http://snag.gy/Tvsgi.jpg The tiniest push on the gear on the left causes the gear on the right to fly at thousands of RPM. Of course, there would be a ton of friction in the system to overcome. However, what if the left gear was a pinion connected to a rack that was pushed by an extremely powerful, yet slow-moving source, such as a glacier or tectonic pl…

So the total gear ratio of that gearchain comes out to something like 1119:1, though that's lower than you intended I suspect because you geared it down with a 9:57-or-so ratio on the end. The penultimate axle is geared at 7089:1 with respect to the first axle. Now while that implies a rotation of one degree of the first axle is accompanied by a rotation of the penultimate axle through 20 or so revolutions, in practi…

So do gears basically help you distribute kinetic energy, or do they serve other purposes?

Re: Show HN: Sketch, connect and simulate gears and chains

#57

Post by EzGraphs »

Reminds me of Mindstorms:

http://www.amazon.com/Mindstorms-Children-Computers-Powerful...

In the intro of the book Seymour A. Papert describes how gears provided an early concrete framework that made understanding abstract mathematical concepts presented at a later point much easier to visualize and apply.

Re: Show HN: Sketch, connect and simulate gears and chains

#58

Post by jameshart »

pfraze wrote: post #55
jameshart wrote: post #48

Earlier quoted context omitted.

So the total gear ratio of that gearchain comes out to something like 1119:1, though that's lower than you intended I suspect because you geared it down with a 9:57-or-so ratio on the end. The penultimate axle is geared at 7089:1 with respect to the first axle. Now while that implies a rotation of one degree of the first axle is accompanied by a rotation of the penultimate axle through 20 or so revolutions, in practi…

So do gears basically help you distribute kinetic energy, or do they serve other purposes?

Gears 'distribute' kinetic energy in that they allow you to take a rotational motion on one axis and generate a rotational motion on a different axis. That can be a parallel, offset axis, as in this case, but it can also be at a different angle, using angled or crown gear teeth. So yes, that's one use, certainly. They let you reverse a rotational direction, too - turning clockwise into anti-clockwise.

But the main thing they do is let you trade angular distance of motion against angular force, or torque - same as a lever does, and much like how a pulley system lets you trade off linear distance of motion against linear force. I can make a gear system that multiplies the effective force I can exert by 50, at the expense of my having to rotate a crank on the input shaft fifty times for every time I want the output shaft to rotate. Or I can use it the opposite way around and make an output shaft spin fifty times for every rotation of my input shaft, at the expense that I have to exert fifty-times the force to overcome any load on the output shaft.

Re: Show HN: Sketch, connect and simulate gears and chains

#59

Post by pfraze »

jameshart wrote: post #58
pfraze wrote: post #55

Earlier quoted context omitted.

So do gears basically help you distribute kinetic energy, or do they serve other purposes?

Gears 'distribute' kinetic energy in that they allow you to take a rotational motion on one axis and generate a rotational motion on a different axis. That can be a parallel, offset axis, as in this case, but it can also be at a different angle, using angled or crown gear teeth. So yes, that's one use, certainly. They let you reverse a rotational direction, too - turning clockwise into anti-clockwise. But the main th…

Thanks for coming back to answer. Back to school for me.
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