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Crowd Funding For Crank Physics
BuzzSkyline writes "A new design for bicycle cranks violates basic principles of physics, but that's not stopping the inventor of Z-Torque cranks from trying to raise thousands in start-up capital through crowd funding." The picture looks intriguing for a fleeting moment before it looks silly. Covered in similar style at a site I'm glad to discover exists, the Bicycle Museum of Bad Ideas.
Anyone who says anything against this cranky idea is probably some sort of whack job!
What are examiners for again ? Spelling mistakes ?
You seem to regard science as some kind of dodge... or hustle.
that it cannot be used to extract money from the gullible and hopeful -esp in America where the common man knows so much more than the engineer or the scientist...so in that sense it is a good idea just like all the weight loss and sex aid supplements you see on late night cable
-I'm just sayin'
because this guy will get funding and the beta testers WILL report that the new cranks have totally transformed their biking "experience"
...can quite comfortably fit outside it.
If computers were people, I'd be a misanthrope.
Biomechanics doesn't always follow the rules of simple static analysis. It's possible that by moving the pedal so the cyclist's legs are in a different position during the pedal cycle, it's possible that his muscles could more effectively power the pedals. Kind of like the old oval Biopace chain rings that were supposed to optimize pedal strokes, but ended up having little effect.
I'm skeptical that these new cranks make any significant difference since modern bike racing teams do a lot of biomechanical analysis to optimize pedal strokes, and they probably would have discovered this technique long ago if it were true.
But in any case, this can't be dismissed just because simple physics says that it has no mechanical advantage.
These guys don't know the difference between "then" and "than." They are obviously just your garden variety Internet trolls.
One problem with long cranks and a low bottom bracket is the possibility of hitting your pedals on the ground during a turn.
This makes is worse by making it even more likely to hit the crank arm on the ground.
The alternative to limited government is unlimited government.
...or wyse enough friend to tell him he's just plain wrong!
I've seen this before a dozen times or more as an engineering consultant. Some crackpot inventor comes in for a consultation with an engineering idea that "will save the world"*, and they say it works great with the soda-bottle-and-silly-straw model they built of the idea in their bathtub. They have $4 million in investment lined up, and they ask me to work up the numbers to show the feasibility of the idea.
2 minutes later, after trying to explain to them the 0th/1st/2nd Laws of Thermodynamics and how their device can't work because it violates all of them, it degenerates into a shouting match where the inventor (with an on-line PhD in cosmetology or similar) now is trying to tell me how the 0th/1st/2nd Laws of Thermodynamics do not apply to their device. I wish them luck and then send them to the door.
I don't envy them, because their options are 1) somehow continue to snow the investors until they make a major ass out of themselves when demonstration day inevitably comes and/or 2) slowly come to the realization that the 0th/1st/2nd Laws of Thermodynamics DO apply to their invention and that they somehow need to backpedal (pun!) out of the situation.
I'm not against garage inventors, but I wish them the humility to take 30 minutes to get their ideas vetted by a professional in the field before they make asses out of themselves and many others. There are many areas in engineering where the legitimate ideas are getting drowned out by the noise made by the uneducated hucksters.
*actual phrase used.
I think this is the guy's website
Just another example of form over content. Slick video, stupid idea. As TFA states, it does not mater what shape the lever has. But that won't stop ignorant people invest in this idea. In my opinion, even the presenter does not believe in the idea.
Can I get twice the funding?
It's called a 3d printer with PLA, and a technique called casting. Heck since one sode of this will be flat (ok, two sides,) you could probably do this with ABS plastic. Sure you need a software model, but you cnd probably frough one up fast enough in SketchUp, Blender, or even Corel Draw, simply knowing the requirements for mounting to the shaft and mounting pedals to it. And you'llprobalby have to tap the holes for securing each, but so long as your 3d Printer can handle the dimensions of a crank arm, you're golden.
Cast em out of aluminum, brush and laquor them, have fun with the custom cranks. Or if you're less concerned about weight, looks, durability, etc. cast em out of lead, gold, silver, platinum, use the abs print as a core for a carbon fiber build. Use the model to CNC them out of a block of stainless. Build a small mass driven generator into them and add LED's and an arduino to show of pretty lights, present a message as you're riding down the street, whatever.
You never know...
Automatically?
I think: "TIME CUBE"!
"Flyin' in just a sweet place,
Never been known to fail..."
Manual of Patent Examining Procedure; 706.03(a) Rejections under 35 USC 101 III A rejection on the ground of lack of utility is appropriate when ... (2) an assertion of specific and substantive utility for the invention is not credible. Such a rejection can include the more specific grounds of inoperativeness! Such as inventions involving perpetual motion.
You seem to regard science as some kind of dodge... or hustle.
Nothing to see here, even less to "invest" in.
The length of one of the elements is innecesarily longer than the final crack length. I bet it's a nighmare to pedal thru irregular terrain, collisioning with the ground every second.
Actually, this could work but not due to leverages: If this crank extends the diameter of the rotation, like an extra gear it will allow to modulate power differently. Though adjusting the gearing will accomplish the same result...
So, at best, he's reinventing the wheel...
FYI, If my time at the gym bro-learning meat-head science is worth anything, than cycling is a very inefficient movement since it overrides the hamstring which counts for over 50% of the leg muscles. Now, this doesn't account for energy output - though since this "tours" take days I imagine the body can produce more power - In that respect, it's quite possible to invent a new type of bicycles that will involve those muscles and will allow more top speed... Technically bro-speaking...
If this crank extends the diameter of the rotation
Just making the crank longer would do that. The shape bears no effect on the diameter of the rotation as long as the distance between the pedal and the axle stays the same. The shape would only bear an effect if the crank dynamically changed shape during the rotation, but alas, this is a fixed construct.
You decide.
the bracket axle to the middle of the pedal and make a arm that length and you will have the same thing.
I wonder if the report as a "Scam/Fraud" has an automated threshold for removal of a certain fundraising video on youtube:?v=O-WN8kPolug
Really? Slashdot can't even understand something that would be taught in week one or two of high school physics? Doesn't anyone remember the calculations for torque and how when "johnny" ties a rope to the end of the wrench and pulls on that for "torque", it doesn't actually change anything?
Also, this has been all over the internet quite literally for months. Slashdot is getting this story after it is how many months old?
Grandpa: My Homer is not a communist. He may be a liar, a pig, an idiot, a communist, but he is not a porn star.
What happens with this design if the pedals are at TDC and BDC, with a weight hanging off the top pedal? It should go forward as that is the direction of the "Z" arm. By my understanding that is one of his design goals, to eliminate the dead spots as with regular straight arms in the same situation nothing happens (you would need forward motion to move the arm).
Of course, there are plenty of problems with this design that are greater than this problem which it might marginally solve. And in all my years of cycling I never found myself cripplingly stuck in TDC/BDC, you need very little power to get out of it and if you're in the act of pedalling you are likely not going to even notice it.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
"only bear an effect if the crank dynamically changed shape during the rotation"
Wait, that's not what it does ?! So, it's just a Z shaped crank ? wow... I thought it at least extends at some degree to allow better leverages at key angles thus allowing the muscles to extend and retract to a greater degree. Since the muscles don't exert the same amount of force at different degrees... Well, it just made some sense that way even if the energy lost from the extra moving parts...
So it's essential dead weight... Just wow...
I've spent enough time on a bike to tell you the leading edge that breaks the surface tension of the air as you pedal is a critical component of air resistance.
Trust me, when you are constantly breaking wind, or if you routinely draft in the turbulence of the rider in front of you who is breaking wind, it will degrade your performance at least 10-20%.
Never ask for directions from a two-headed tourist! -Big Bird
Are taxes on the stupid a bad thing?
New bad ideas can be patented. It isn't supposed to be possible to patent old bad ideas. The problem, is that old bad ideas are often badly documented, because they are bad ideas. If the patent examiner doesn't find the prior art in the limited time available, then the examiner is likely to grant the patent.
How often do you get to discuss a crank with a crank... too bad its not April, I'd have gone with the prank crank thanks.
Oh come on. I'm not giving my money to anyone who can't write a sentence.
----------
Any problem can be made unsolvable if there are enough meetings made to discuss it.
I always slow way down when the guy up front is farting. Don't have to breathe as much of it that way.
but post a story about "warp drive" and "FTL starships" and the Space Nutters will come slobbering out of the woodwork. Sure, we'll have warp drive in a few years...
Hmm, subtle pun or can't spell??
Mostly random stuff.
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They basically dog leg the peddle arm and claim there's an advantage. I thought it was linked in some way so the length changes during a stroke. It isn't even that clever it's just a pointless waste of aluminum. Even a variable length one wouldn't work because it'd throw off you rhythm. Bicycle peddles haven't changed much in over a hundred years for a reason.
Whoa, OK, I misunderstood that for a moment.
*** "Freiheit ist immer die Freiheit des Andersdenkenden". -- Rosa Luxemburg ***
If you read one of the papers, from Florida Atlantic University, referenced on the site, the author claims that the advantage comes from an 'intrinsic favorable flexure mode." Basically, he is saying that the flex at the joint of the Z shape creates a smoother ride and higher torque at specific angles (not peak torque however).
While I find it unlikely that the effect is as positive as stated in the article, it is plausible that there is a small second-order effect due to non-rigid behavior of the crank. It is claimed in the article that this effect was tested independently, however I can't see how a flex in the pedal would produce any other effect than to steal energy away from the peddler.
Besides, if you want more torque while biking, just use clip-ins.
Judging by the photos, it appears that the Crank with Z-pedals has a larger Moment of Inertia ( http://en.wikipedia.org/wiki/Moment_of_inertia) than the Crank without Z-pedals.
Perhaps that increased moment of inertia has a flywheel effect that helps ease the pedaling? I wouldn't expect it to make a difference, but then again bicycle racing is so incredibly optimized -- just look at those stupid looking helmets bicycle racers wear to improve their aerodynamics -- so perhaps the riders can tell the difference.
First thing you should do is ditch the cranks that came with your bike, and find some 175 or 180mm cranks instead. You have the longer legs required to use them, after all.
Hal Spacejock: Science Fiction with Nuts
Just take a look at those infomercials that try to tell you that 1) for your entire life you've been wobbling around about to fall over
The solution to that is to become a Weeble, because Weebles wobble but they don't fall down.
The crankarm is likely just a distracting gimmick to confuse people. The real secret sauce would be putting planetary gearing inside the bottom bracket to give the rider heaps wider gear ratios without any extra chain or unwanted chan slop. Combine that with an existing two deraileur system driveline, and you could climb hills and scream on downhills like nobody's business with fairly normal tooth ratios on chainring and gearset and have no worries about throwing your chain.
Physics violations? Derp... Look closer.
At least that's what I'd suspect.
You think that's bad? An entire town in Tennessee was suckered by HEFT industries, promising them to build a factory for a free energy device.
http://ucbjournal.com/news.php?id=127
http://w.overtoncountynews.com/index.php?option=com_content&view=article&id=5330:heft-has-officially-left-the-oshkosh-building-leaving-dirty-toilets-behind&catid=119:business&Itemid=183
One measly zig? That's not going to efficiently couple my torque rotation constant. I want a crank with a minimum of five zigs and, for fuck's sake, a bare minimum of *three* zags... and that will be the "intro" model. The "pro" crank will come with seven zigs and five zags. The "custom" option will end the zigzags with a loop.
Throw in enough, and the bike will basically pedal itself. All I need to figure out now is how to perfect my shake weight handlebars. Still having problems with the braking on those things.
FYI, If my time at the gym bro-learning meat-head science is worth anything, than cycling is a very inefficient movement since it overrides the hamstring which counts for over 50% of the leg muscles.
If you do it right, you use your hamstrings. They kick in toward the bottom of the stroke, and pull across the bottom and up the back.
> A new design for bicycle cranks violates basic principles of physics
At first I was prepared for a crank out of MC Escher, that couldn't exist in the real world. But it's just snake oil. Sigh. In a Kevin Kline voice; DisaPOINTed.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
How is this different from alleged gurus claiming that foo-oriented programming is a silver bullet and selling books, seminars, special languages, methodology consultants, and so forth without first having objective evidence?
It's not just bicycles.
Table-ized A.I.
This guy almost got me to tie up $1 on kickstarter, but plenty of other people covered the comments.
Pun intended?
Good old USPO. Of COURSE they granted a patent for this wondrous idea!
They also accepted a patent application (in 2012) for a chain power transmission system for bicycles.
http://www.google.com/patents/US20120277046?dq=z-torque+crank+arm&hl=en&sa=X&ei=ZPvwUICCCbC_0QHP3YDYAQ&ved=0CE4Q6AEwCQ
I'm sure any resemblance to the Derailleur gears we've all known about since the late 1800's.
Obvious? Apparently not obvious for our USPO wizards. Prior art? Ah well, perhaps the "inventor" changed the number of teeth on a sprocket? Yeah, that's the ticket!
Sheesh .. what a bunch of maroons.
And they go to extreme efforts to reduce it. Muscle strength spent flexing the crank is wasted.
Same thing for crank weight. They go to extreme lengths to shave grams off their bikes, and even more to reduce weights of moving parts.
The idea that this is a great, new, magic crank because it's flexible and heavy is ridiculous!
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
This inventor has apparently managed to duplicate the invention of medieval alchemists: Transmuting gullibility into gold.
Once upon a time, I had a wall-mounted coffee mill of high quality and life-long quality. Every one to two years, I'd be sending in the crank handle because it had broken off. It was some cast material, granted, but the main problem was that it had an S-curved design and consequently stress points that were not really dealing well with discontinuities in the mechanical resistance of the coffee beans.
The curvage of this Z-crank is way worse. With forged steel, it would likely be manageable to avoid stress-induced breaking at reasonable weight. However, the material looks like aluminum. It would likely just snap eventually, with a life time significantly shorter than that of a straight crank.
The guy uploaded the analysis from a professor of Florida University which notes improvements over regular cranks... However, not the ones claimed in the video.
What is nice is that the first paragraph contradicts the video : "As far as mechanical advantages is concerned, the angle crank does not offer any more than the traditional straight-link crank[...]". The Pr sees the higher momentum of inertia as beneficial for pedalling as well as the bending mode, concluding that those two properties are obviously not intended.
As far as I am concerned I am not quite sure I would like to have more momentum of inertia to overcome and I find the effective improvement from flexure mode dubious.
The crank has a BEND in it BUT for physics it is a perfectly straight crank, a direct line from the pedal join and the center of the gear. It therefor does NOT change the position of the pedal in the circle of movement despite how it might appear. 0 degrees and 180 degrees is STILL the pedal being at the top OR bottom regardless of how the metal of the crank zigzags.
Somewhere else it is suggested that the extra material creates a flywheel effect. In theory, this is true but since ANY crank has weight ANY crank will be in object in motion that stays in motion until an opposite force stops it (the friction of the rest of the bike). And if the extra weight is what does the trick, why make it out of aluminum (the currently selling model) and the new one out of carbon? Make it out of cast iron, inlayed with lead.
Perpetual motion machines usually have some kind of charming "but it should work because it looks cute" aspect but physics ain't cute or charming, it just is. But people who believe in beards in the sky, karma, justice outside a court system, democracy are always looking for the fantasy to beat reality.
THe whole "dead" points while cycling by the way only happens in extreme cases where you are standing on the pedals and encountering a lot of resistance. In normal daily cycling the sheer weight of your leg, the motion will just continue smoothly on.
This crank solves an issue that isn't there and doesn't solve it either.
Oh and if you fit it on your bike, you just lowered the ride height of your bicycle, enjoy scraping them across the ground in corners.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
On a bike crank, you have about a third of an arc where your leg has power to offer.
With a straight crank shaft, you blow a chunk of that power pushing directly into the center of the axle as opposed to perpendicular to it.
Try putting a wrench on a tight nut and pushing on the tail end of the wrench directly toward the nut. It's not going to move.
If you shift to just off 90 degrees to the nut, then you now have somewhere to go, but it's a hard damned push and most of the energy you expend is absorbed in trying to flex the nut along its own shaft rather than turn it. You turn that energy in heat rather than motion.
With this Z design, if you stand upright on the pedal at its highest point, it'll move at peak efficiency where you leg has the most to offer.
Physics involving a perfectly perpendicular push at all points on the arc would render this design pointless. But our legs don't work that way.
There's a reason corrective bends are useful.
Angle of attack matters.
Just figured out why this doesn't work.
The fleeting moment was longer for me than usual today.
So that I'm always cycling downhill.
If you were blocking sigs, you wouldn't have to read this.
The problem, is that old bad ideas are often badly documented, because they are bad ideas.
Did I find it?
The one perfect example of begging the question?
Is there a prize or something?
The length of one of the elements is innecesarily longer than the final crack length.
That was surely just a typo, but when indeed this thing finally cracks, it will leave you with a veritable leg dagger rather than just a sharp break-off edge.
JC avoids a question. Tell you anything about success trolling? He spell what he did for a living on his resume he posted. Failure's the result of his trolling since he yanked his resume online once he was aware of that misspelling. Now, that's hilarious. It was that way for years!
OK. I haven't got one in my hands to test, but he seems to be saying that the principle lever arm IS longer.
Crude ASCII art:
Typical crank lever: ----- (5 dashes)
_
\
His crank lever : ------- (7 dashes)
I'm sure that many of you, like me, have used a hammer on long wrench to help get it turning. This sounds like a
similar idea; he's making the lever longer and focusing the effort elsewhere (swinging the hammer). As he says,
it's because legs cannot move that far, so he moved the pedals back in.
Torque is the cross product of force and lever arm length. T=FxL. = F * L * sin(theta)
A longer arm L, will produce greater torque T.
But in bicycles, Theta is important. With traditional bikes, we know that our
maximum force is applied at 3 o'clock and 9 o'clock positions. So, this pedal
introduces some added complexities because it moves this position to different
points on the dial. 6 o'clock is no longer a zero Torque position for the new
crank. This change could subtly help the cyclist feel like he has fewer dead spots.
This is where real life tests are important.
But let's simplify this and refocus on the 3 o'clock and 9 o'clock positions where
the angle would be 90 degrees for a typical bicycle crank. For our new Z crank
we break the force into components, we have a downward (Normal) force
and an outward force. It's the downward component of the force that will be
applied to the longer arm. If this force is sufficiently less, then it could cancel
out the advantage of the longer arm L. (But a part of me is thinking that
the outward force could actually help the cyclist pedal more smoothly.)
OK. Some really simple maths:
Using 5 dashes v. 7 dashes for length and a normal force of unity:
If the angle Theta is about 45 degrees, then the new design is a loser,
resulting T=4.9 instead of T=5.
If, however, the angle is larger, say 60 degrees,
then we have T=7* sin(60) = 6.1.
That's an increase in torque!
Actually, anything 46 degrees and greater is a winner in this 5 v 7 scenario.
The upshot of this is that without one in my hands, I can't do a detailed analysis
to prove it one way or another. And I don't feel like doing any fancy mathematical
simulations at the moment. Suffice it to say, that things are more complicated
than y'all are understanding them.
These are going to look awesome with my Biopace chanrings on them.
... features Lotus Notes and a machine gun.
It is the finest available.
See you space cowboy
This thing DOES work to reduce _perceived_ pedaling torque. Everyone on here is bringing up the trivial physics issue that torque is the same - believe it or not, that's NOT THE POINT.
The point is that this pedal's design advances the angle of the rotation cycle by 15 or 20 degrees due to the kink. That means at the TOP of the pedaling cycle, the cyclist now HAS leverage from a downward push on the pedal. Normally, at the top of the pedal cycle, you get ZERO leverage from pushing down. You have to normally push 100% forward at the top of the pedal cycle (because the pedal axis is pointing perpendicular to the ground and pushing down pushes you into origin of the wheel). Pushing forward at the top is much harder (think about it - it's a weird angle and you have restricted muscle leverage up there) than being able to push down with your whole gravity-assisted body weight. This design shifts the deadspot from the normal 0 degree point at the top of the cycle to a point further down where momentum is presumably easier to deal with.
It's like everyone on here gives themselves a medal for understanding physics 101 without actually taking a look at the effective biomechanics of the situation. Torque being the same does NOT equate into a similar pedaling experience. The offset rotation is the selling point of this thing. People should try it before commenting.
and you have a winner!
This is all easily explained by one simple mistake: you are looking at the wrong crank. There is one, funny shaped crank in the video that seems to be strangely effective at extracting more work (in the form of money) than it should. Unfortunately it's also the one giving the sales pitch which may be where the confusion arises.
this is achieved using oval shaped gears
Really? Slashdot can't even understand something that would be taught in week one or two of high school physics?
At least in Canada moments of forces are no longer taught at school. They may get some basic archimedes lever-style principles but the first time students see proper rotational dynamics with moments of forces is when we teach it to them in a first year introductory physics course at university. Even AP physics B skips this stuff - you have to do physics C - so I imagine the US is the same.
Haven't ridden a bike hard since I was young. But I do remember the blisters on the inside ankle joint. Mebbee a canted angle relieves you of that worry, so you can pedal .001 % harder.
Listening to this discussion reminds me of the 'Airplane on a Treadmill' internet debates from long ago. There are 2 sides to this discussion and (at least) one side is not listening to the other. As I see it:
Side 1 The Z-crank is a simple change in geometry from straight crank arms. If you assume a rigid body, then the shape makes NO DIFFERENCE to the torque/energy transfer characteristics. The larger mass will likely have a higher rotational inertia and an increase in total bike weight, but these effects are assumed negligible for the purpose of this discussion.
Side 2 These folks assume the crank is not rigid, yielding some spring energy storage at certain positions in the crank rotation and giving it back when the cranks is in a different position. It is quite plausible that this happens, the question is: Is this energy storage significant and beneficial to the rider.
It would be nice to see arguments on the relative merits of each and do away with all the finger pointing.
Looks like we'll know how well it works when the next Tour de France runs{grin}
If they ban it it MUST work... right?
Someone is going to make money off this idea... it's just too shiny for people to pass up... Hopefully the lesson the investors learn will serve them well in the future!
Most power is applied by cyclist from 1 to 4 o'clock in the pedal stroke. This crank allows cyclist to dynamically adjust the effective gear ratio mid-stroke by changing his knee angle, and therefore the effective crank length, during the power portion of the stroke. Mid-stroke adjustment creates the possibility of a better bio-mechancial match to the leg. The only way to know if this is really beneficial is experiment.
Of course, it's obvious that the crank is the same as a standard crank ** for a given knee angle **. The interesting aspect of this crank is the possibility of the rider dynamically adjusting effective crank length during the stroke.
...he's not marketing to engineers. Or anyone else who actually understands torque.
That said, there is always a market for these types of things...
Quoted directly from their website (http://z-torque.com/Video.aspx):
Results: Participants achieved similar maximal oxygen consumption, peak power outputs and gross efficiencies with the Z-Torque and normal crank configurations (Table 1). In addition, ratings of perceived exertion (RPE) at 150 and 200 W, heart rate (HR) at peak power output, 150, and 200 W, and cadence at 150 and 200 W were not significantly different. However, participants perceived their effort to be significantly lower at peak power output with the Z-Torque crank.
--
So it's a placebo. Or Nocebo, depending. You believe the pedals make it easeir, so it feels easier, but it's exactly the same.
Yes, there are 2 points at 6-12 and 12-6 that are dead in an normal crank. The 'recover' (bringing it back up to 12) is also wasted time when only one leg is doing the work. So you are only pedalling at 50% mechanical efficiency unless you pull upwards with the resting leg. I don't think this has been solved.
Almost all of these conversations are looking at max torque. Max Torque is only achieved once per peddle rotation. Torque is R corss (X) F. Or the magnitude of the Force times the magnitude of the lever arm times the sine of the angle between them.
You don't need longer lever arms to get more torque, since in most cases its the average torque (POWER) that matters, you simply need a design that allows for more of your motion to drive the wheels.
Note that the topic crank arm doesn't accomplish this either. No fixed axis circular motion would. It would have to be a compound motion.
http://z-torque.com/About/TheInventor.aspx
(subject line punctuation left as an exercise for the reader)
Any chance of elastic deformation giving a boost? cranky crank?
--
It was a dark and drunken night. Four shots called out -- drink me.
It doesn't violate the principles of physics. It works exactly as the physics determines it should. What it does do is take advantage of people's misconceptions and ignorance of physics.
It's the old story of more money than sense, or to be more accurate, the (almost as) old story of taking advantage of people with more money than sense.
One of the universal rules of happiness is always be wary of any helpful item that weighs less than its operating manual
Back in the late 70s one of the bike mags had a piece on an Italian company who were marketing a beautifully made crankset with right angle bends in them.. They weren't impressed with the idea then, either.
Now, as to the efficacy of oval chainwheels.....
Star Trek transporters are just 3d printers.
So let me get this straight - the more zigzags the crank has, the less effort? How about a dragon curve crank? It could be made out of paper, since the pedalling would be so easy it would exert hardly any pressure!
... I actually had this same idea several years ago. Then I built a simple prototype out of wood, tested it, and saw that it didn't do squat. Apparently my second thought should have been, "Don't test it, just build it and charge money for it."