Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

Posted by Soulskill on Tuesday December 2, 2014 @10:14PM from the gearing-up dept.

Zothecula writes: A new transmission device that uses magnetic levitation to almost completely eliminate friction and wear has been developed as part of the MAGDRIVE research project, a collaboration of seven European nations. The creation of the unit entailed the development of a magnetic gear reducer and corresponding frictionless magnetic axles. Aimed primarily for use in spacecraft due to its extended mechanical life, the system is also adaptable for use in automobiles, railways, and aircraft.

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never in America! by Anonymous Coward · 2014-12-02 22:16 · Score: -1

Keep that magical eurofag socialist shit off our God given soil. Yeeeeeeeehaaaaaaaaaaawwwwwwwwwww.
1. Re:never in America! by Anonymous Coward · 2014-12-02 22:56 · Score: -1
  
  Yup. These euros are getting too big for their boots. We all know that the US are best. A nuke should take care of it....
inb4 by Hognoxious · 2014-12-02 22:16 · Score: -1, Offtopic

inb4 "No good, acors not murrcan" crowd.

--
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
1. Re:inb4 by Anonymous Coward · 2014-12-02 22:20 · Score: -1
  
  u fa1l 1t
fRosstY p1ss by Anonymous Coward · 2014-12-02 22:17 · Score: -1

1st!
1. Re:fRosstY p1ss by Anonymous Coward · 2014-12-02 22:23 · Score: -1
  
  no
Woot :) by Anonymous Coward · 2014-12-02 22:18 · Score: 0

Electrifying progress
witnessing history by Anonymous Coward · 2014-12-02 22:36 · Score: -1, Troll

Not a long time ago, I was just a normal internet user that surfed various news sites like Sladshdot, reddit, or wsj.com. I read a story, perhaps clicked onto some links it contained, and I was mostly happy with my life.
Then, one day, I surfed Slashdot. It was one of those days you will remember for the rest of your life. So, as I surfed Sladshdot, the title of a story got my attention. I read the summary. The topic seemed interesting, so I decided to read further. I read:

Read on below for the rest what Bennett has to say.
Usually I don't read first line of a story which contains the user who has submitted it. On that day, I didn't neither. As I've only read that bottom line, I asked myself: who is this misterious Bennett? I decided to click onto the "Read the comments" link to read more of the story that was, as it seems, written by some Bennett. During reading, I was already impressed by the clear and detailed but still concise structure of the text. As I finished reading, I was convinced it was the best story I've ever read on Sladshdot, or any comparable news site. I asked myself: perhaps this misterious Bennett has contributed more frequently than just once?
To find that out, I went to Sladshdot's search bar and searched for "Bennett". I clicked the second entry, and it began with:

Frequent contributor Bennett Haselton writes
I searched for the "Read on" line, and I was happy when I found it. As it seemed, he was a frequent contributor. However the story was on a topic completely unrelated to the topic of my article. Would the other article still be as insightful as the first? And the other stories in the search result? Would they be also by Bennett? Or someone else? I decided first to be happy to have found such an insightful article, and decided to make a photograph of me, before I read the second story.
I still have that photograph of me and I can see the hope and the satisfaction in my eyes, the hope that the other stories are also written by this brilliant author called Bennett, and the satisfaction of having read such an insightful article. As I've read the first couple of stories by Bennett, I couldn't believe what my eyes saw: all the stories were as insightful or even more insightful than the original story I read. I asked myself whether the spectators in the Globe theatre would have felt the same way when they watched a piece by shakespeare: Witnessing history of writing. I realized Bennett is one of histories great writers.
As I've finished reading all contributions by Bennett Haselton on Sladshdot, I went back to the first Bennett story, and read them a second time. I sat three days straight, missing all social events during that span, only reading Bennett's stories, and reading them again and again. During that time my eyes opened to the fact that my whole life, I've known nothing. Bennett's stories explained every aspect of very complicated things in such detail, that I formed something in my mind. First, I couldn't describe it what it was, but years later I know that, for the first time of my life, I formed something called "opinion" on a topic. Previously, I've only adopted opinions from others, but Bennett's stories enable people to make their opinions for themselfes, to form them. With his stories, Bennett gives you the material to form your own opinion on your own. I know you will say that you can form your opinion on your own, and that you don't need Bennett for that. I
disagree with you. What you call opinion, is in reality just ideology you imitate from others. You don't form your opinions, you don't have them.
Every time Bennett writes a new story on Sladshdot, I take a free day and spend it reading the story
PBS had a documentary... by Anonymous Coward · 2014-12-02 23:04 · Score: 3, Interesting

On 5-10 years back about classic cars from some museum in SoCal or something.
The 3 primary vehicles they discussed were:
A 1900s era Battery Powered car with a 25 mile range.
A Steam powered car capable of 'gas-like' performance, given ample 'warmup' time.
And a 1920s or 30s electrocoupled automatic transmission car that I believe used increasing rotational speed to more closely couple the engine to the output shaft (Can't remember if it also had gears or if the coupling mechanism doubled as the 'gears'.)
Point being: So they're finally getting back to R&D on 'non-mechanical' coupling mechisms in modern vehicles. Yay! Only took like 90 years.
1. Re:PBS had a documentary... by ledow · 2014-12-03 01:13 · Score: 5, Insightful
  
  If something has been abandoned for 90+ years with no significant advances in the area, it's probably for a reason.
  The upper limit on what such gearing could do is quite low. You're comparing a steel-pushing-steel scenario with one of trying to turn one magnetic wheel by pushing another near it. It's a loser except in ultra-specialist applications with exotic materials (Space? Fine. Your car? Unlikely).
  Battery powered cars have been around forever. UK milk floats were entirely battery powered for decades, delivering hundreds of pints of milk to every house in the local town - they just used lead acid batteries and charged overnight. If you ever got stuck behind one, you quickly (!) found out the limitations of the technology of the time. We've moved on from there now, but only very, very recently.
  Some huge trucks still have things based on variable transmission technology, so the entire gearbox doesn't have gears but just slides into the most convenient gearing automatically. They've been around for decades. And they work by using a strong belt that can slide up and down a conical shaft. I kid you not. Every few years, they are re-invented under another brand / patent / material and actually do quite a good job. But they are still considered specialist parts because we can't overcome their weaknesses.
  Wankel engines were still in mass production until very recently (I believe Mazda don't have newer models that still use them?). Again, they do everything you would want and were constantly reinventing themselves for decades.
  The problem is not that it's been done before. It's that it's been done an awful lot and not much more can be done that way. As such, although we have stronger room-temperature magnets, they aren't THAT much stronger. Superconducting magnets might be considered "new" but we can't make them practical yet - except in the absolute zero and vacuum of outer space.
  There's nothing wrong with going back to the old, but you have to add something new (e.g. the clockwork radio was hailed as genius because it took the old and made it do something "new").
  And I'm not sure this does that at all.
2. Re:PBS had a documentary... by nukenerd · 2014-12-03 01:17 · Score: 1
  
  Forgot the fluid flywheel.
3. Re:PBS had a documentary... by jafiwam · 2014-12-03 01:33 · Score: 4, Insightful
  
  Some huge trucks still have things based on variable transmission technology, so the entire gearbox doesn't have gears but just slides into the most convenient gearing automatically. They've been around for decades. And they work by using a strong belt that can slide up and down a conical shaft. I kid you not. Every few years, they are re-invented under another brand / patent / material and actually do quite a good job. But they are still considered specialist parts because we can't overcome their weaknesses.
  For someone asserting they know all kinds of "unknoiwn" details, you sure are behind.
  The description above is called a "Constant Velocity Transmission" and both Nissan (recently) and Subaru (since the 70's) have these. Subaru has had MOST of their new non-performance car fleet use CVTs for the last three years. Nisssan's CVT uses a "pusher" belt made of stacked plates connected by a chain. Subaru, a regular chain.
  This is not "specialists" parts anymore. This is just a different type of automatic transmission.
  True, "going back to the old" works sometimes, often that is because materials and engineering concepts have advanced far enough to actually make the stuff work now. That doesn't mean tinkering with, or taking another try at these old methods isn't worthwhile.
4. Re:PBS had a documentary... by tom17 · 2014-12-03 02:11 · Score: 2
  
  The Corolla has CVT now too. It's getting pretty common out there in some mass-market cars.
  Also, on his other comment about Wankel engines, I believe that Mazda are re-introducing one. Just rumours now, but it's not necessarily dead yet.
5. Re:PBS had a documentary... by RatherBeAnonymous · 2014-12-03 02:19 · Score: 1
  
  UK milk floats were entirely battery powered for decades, delivering hundreds of pints of milk to every house in the local town - they just used lead acid batteries and charged overnight. If you ever got stuck behind one, you quickly (!) found out the limitations of the technology of the time.
  Limited? Perhaps they were, but they did provide for some thrilling television.
  https://www.youtube.com/watch?...
6. Re:PBS had a documentary... by Anonymous Coward · 2014-12-03 02:25 · Score: 2, Informative
  
  If your car has a CVT, it's a "Continuously Variable Transmission". The gear ratio continously varies, hence the name.
  It's unrelated to the CV ("Constant Velocity") joints on the transaxle. Those are joints that maintain a constant velocity on the input and output shafts even though there is a bend in the middle, as opposed to a universal joint that has some change in angular momentum that varies based on the angle of the bend.
  dom
7. Re:PBS had a documentary... by Anonymous Coward · 2014-12-03 02:27 · Score: 0
  
  every vespa scooter has cvt
  nothing common with "magnetic" or "extended mechanical life"
  ant "magnetic" things do not have "extended mechanical life" because of "currie point"
8. Re:PBS had a documentary... by Anonymous Coward · 2014-12-03 02:29 · Score: 0
  
  In spite of some technological inaccuracy, I believe one of Ledow's points stands. It is one thing to introduce this technology in outer space with little to no mechanical stress and wear, and quite another to implement it in ordinary earthbound vehicles. So to the people developing this, congrats if they can get it to work in a spaceship, but that doesn't mean that a successful transition to automobiles is feasible.
9. Re:PBS had a documentary... by stjobe · 2014-12-03 02:34 · Score: 1
  
  Some huge trucks still have things based on variable transmission technology, so the entire gearbox doesn't have gears but just slides into the most convenient gearing automatically. They've been around for decades. And they work by using a strong belt that can slide up and down a conical shaft. I kid you not. Every few years, they are re-invented under another brand / patent / material and actually do quite a good job. But they are still considered specialist parts because we can't overcome their weaknesses.
  My 2012 Toyota iQ most definitely isn't "some huge truck", and its Super CVT-i transmission most assuredly doesn't have any "weaknesses" that needs to be overcome, nor is it considered "a special part" - it's just another option on the options list.
  In fact, after having driven one for three years, I'm not sure I'd want to have a "regular" automatic gearbox, and I'm absolutely sure I don't want to go back to manual. Rush-hour traffic no longer feels like sitting in a pedal car...
  
  --
  "Total destruction the only solution" - Bob Marley
10. Re:PBS had a documentary... by wvmarle · 2014-12-03 02:36 · Score: 1
  
  If something has been abandoned for 90+ years with no significant advances in the area, it's probably for a reason.
  One of those reasons may be that 90 years ago they did not have the super strong rare earth magnets like we have now. They're commonly used in places like hard drives which massively pushed development of such permanent magnets, and pushed the cost down.
  As your attitude towards such abandoned technology is shared by many people, it may be forgotten about, and receive less attention than it deserves. Until someone realises that there is now technology available that makes the idea viable - like the much stronger magnets, allowing for stronger connections, and the demand for super reliable, super long life, super low friction devices for spacecraft which obviously didn't exist 90 years ago.
  Another such example is the hybrid and electric cars of today, which were made possible thanks to great advances of battery tech which in turn was sparked by the demand for mobile phones and related devices.
11. Re:PBS had a documentary... by Applehu+Akbar · 2014-12-03 02:54 · Score: 1
  
  You need to have your head examined. Check into any major hospital to have this done and you will see an Earthly application for large superconducting magnets.
12. Re:PBS had a documentary... by hawkbug · 2014-12-03 03:13 · Score: 1
  
  And unfortunately, this is why the reliability of the Nissan Pathfinder has become utter shit. I wanted to buy a 2014 model, but the horrific reviews of failing transmissions at 30k miles scared me and many others off. For good reason I might add.
13. Re:PBS had a documentary... by MightyYar · 2014-12-03 03:44 · Score: 1
  
  Yes, they are finally nailing down the technology for smaller vehicles, but it's still problematic to scale it up to "truck".
  
  --
  W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
14. Re:PBS had a documentary... by David_Hart · 2014-12-03 03:45 · Score: 2
  
  And unfortunately, this is why the reliability of the Nissan Pathfinder has become utter shit. I wanted to buy a 2014 model, but the horrific reviews of failing transmissions at 30k miles scared me and many others off. For good reason I might add.
  I had the 2013 Murano which came out with CVT. 2013-2015 models had CVT problems. Nissan has pretty much solved this and have since added the CVT to even more models. I did lose my transfer case when it was 8 years old and that is still a weak point today for the Murano.
  Its one of the reasons why I replaced it with a Jeep last year. The Jeep Grand Cherokee has an 8-speed transmission. The Cherokee now has a 9-speed transmission. At the time that I was researching the Jeep, ZF was saying that they were working on a 10-speed transmission. With that many shift points, they rival CVT in regards to being in the most efficient power band. Only time will tell if these transmissions will be more reliable than the CVT.
15. Re:PBS had a documentary... by oldmac31310 · 2014-12-03 04:05 · Score: 1
  
  Ernie. He drove the fastest milk cart in the west...
  
  --
  http://www.acetonestudio.com
16. Re:PBS had a documentary... by ledow · 2014-12-03 04:28 · Score: 1
  
  If kept at ultra-low temperatures in a room full of equipment to help do that.
  MRI's are one of the largest users of liquid helium in the world, and it's considered to be one of the bigger supply-chain problems to come in the future (i.e. we won't have enough).
17. Re:PBS had a documentary... by superdave80 · 2014-12-03 05:55 · Score: 2
  
  For someone asserting they know all kinds of "unknoiwn" details, you sure are behind.
  
  This coming from a guy that thinks CVT means "Constant Velocity Transmission"...
  CVT = Continuously Variable Transmission
18. Re:PBS had a documentary... by RockDoctor · 2014-12-05 14:33 · Score: 1
  
  it's considered to be one of the bigger supply-chain problems to come in the future (i.e. we won't have enough).
  Oh, people have noticed that little train-wreck ahead, have they. That'll be nice.
  Nobody is doing anything about it, of course?
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
19. Re:PBS had a documentary... by x_t0ken_407 · 2014-12-06 17:08 · Score: 1
  
  Mitsubishi too has CVT (I have one in my 2012 Lancer). It's made by the same company who makes Nissan's.
Perpetual Motion by Anonymous Coward · 2014-12-02 23:15 · Score: -1

Perpetual motion still won't become a reality.
1. Re:Perpetual Motion by Anonymous Coward · 2014-12-03 00:36 · Score: 0
  
  Pretty sure perpetual motion is a Newton's Law, an object keeps moving unless acted upon.
2. Re:Perpetual Motion by camperdave · 2014-12-03 02:03 · Score: 1
  
  The rest of the universe always acts upon. One of the laws of thermodynamics.
  
  --
  When our name is on the back of your car, we're behind you all the way!
Been done before by Anonymous Coward · 2014-12-02 23:19 · Score: 1

Research into the 'most exciting aspect' (room temperature gearbox) part of this has been done before:
http://www.magnomatics.com/technology/magnetic-gears.aspx
But the idea of using the low temperature and vacuum of space to run superconducting systems seems quite innovative.
One of the main limitations with magnetic gears is that material properties (the saturation flux density of iron/cobalt basically) limits the amount of force that can be transmitted across the airgap. If the motion is being generated by an electric motor in the first place, then it doesn't really make sense to attach this to a magnetic gearbox - you might as well just direct drive the system. Whether the airgap sheer stress is being generated by rotating permanent magnets or sequenced electromagnets, the final torque/speed output limits will be limited by the same physics.
I'm sure there are special applications, but don't expect to see this in your day to day life any time soon.
1. Re:Been done before by TWX · 2014-12-03 02:32 · Score: 1
  
  The other side of the coin too, is that hydraulic solutions like the conventional automatic transmission and its torque converter can be designed to function entirely without electricity whatsoever, and in the past, the only electricity that went to a conventional hydraulic automatic transmission was for getting gear status (ie, the neutral safety switch). Even early lock-up torque converters were hydraulic. Later electronic controls were added, but fundamentally they're still hydraulic systems that need very little tech to operate.
  
  There's a good reason why the least expensive solution often wins-out, people are cost-conscious first, and only a very small group of people would choose otherwise when the cost to do so is high. Space certainly qualifies, but terrestrially I don't expect something that's expensive and complicated to win-out over something that's inexpensive and relatively simple when the simple solution meets the needs of the application.
  
  --
  Do not look into laser with remaining eye.
Efficiency??? by Anonymous Coward · 2014-12-02 23:22 · Score: 0

Sounds great but how Efficient is it? AKA cars can't forward to lose 10% more power over conventional gears...
1. Re:Efficiency??? by K.+S.+Kyosuke · 2014-12-02 23:29 · Score: 1
  
  I think that the Voyager probes would have been happier with a working instrument platform rather than with an efficient but broken one.
  
  --
  Ezekiel 23:20
2. Re:Efficiency??? by SharpFang · 2014-12-02 23:48 · Score: 4, Insightful
  
  Way more efficient than gears for loads it's designed to handle - but it's not meant for heavy lifting; the "magnetic gears" will "slip" if the load is too high, and in this case "too high" is quite low (think force required to move two magnets oriented in "repulsing" way against each other).
  It would be great for stuff like stabilizing flywheels - things that once set in motion stay in motion for years, and may take a long time to spin up or stop. It would work well for things that require very little force, like reorienting the solar panels or aiming the antenna.
  OTOH, stuff like lander wheel bearings or drills for picking samples are better handled with normal bearings that can take much heavier loads.
  It's not a cure-all solution, it's just a good new option for specific applications. You won't use it to build a better crane but gyroscope flywheels could immensely benefit from that!
  
  --
  45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
3. Re:Efficiency??? by drinkypoo · 2014-12-03 00:13 · Score: 3, Interesting
  
  Way more efficient than gears for loads it's designed to handle - but it's not meant for heavy lifting; the "magnetic gears" will "slip" if the load is too high, and in this case "too high" is quite low (think force required to move two magnets oriented in "repulsing" way against each other).
  If you couldn't move high forces with a transmission like this, then you also couldn't generate them with an electric motor, because you couldn't hope for the magnetic fields to turn the stator against high loads.
  
  OTOH, stuff like lander wheel bearings or drills for picking samples are better handled with normal bearings that can take much heavier loads.
  What happens when you put too much torque through a drill? You shatter your bit. What happens when you put too much torque through an axle? All kinds of exciting things can happen, check out some four wheeling videos. There's lots of reasons why some slip designed into the system is not an undesirable thing.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
4. Re:Efficiency??? by Tyr07 · 2014-12-03 00:22 · Score: 2, Interesting
  
  The question is, how much force can it handle? Large electro-mags can pick up entire cars. Sure, it's huge, but it's lifting up 2700 lbs+. Also the surface area is large because the objects surface area is large. If a really high powered small electro mag was used, it would just rip out that piece of metal.
  How many pounds of force can the small one withstand? It's possible using two small unpowered magnets to easily make one that could crush a hand if a hand was implace and restraints were let go on the mags.
  I imagine it could potentially with a little voltage withstand a lot of torque, and limited slip to prevent spin outs, it might be fantastic for rovers.
  They're often in lower gravity environments to begin with.
5. Re:Efficiency??? by rgbatduke · 2014-12-03 00:32 · Score: 4, Insightful
  
  The other point being that it could be designed only to replace the kinetic friction parts of a transmission, the parts that synchronize the system. The gearing itself can probably still be mechanical. Not having to replace clutch plates, for example, might be a nice and relatively easily doable thing.
  
  --
  Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
6. Re:Efficiency??? by Anonymous Coward · 2014-12-03 00:53 · Score: 0
  
  Why did you capitalize "efficient" and what does forward mean here? And how is that an "AKA"? Do you know what AKA stands for?
7. Re:Efficiency??? by drewm19801927 · 2014-12-03 01:00 · Score: 1
  
  3 N-m on the output of the reducer.
8. Re:Efficiency??? by DigiShaman · 2014-12-03 02:29 · Score: 1
  
  A magnetic clutch.
  
  --
  Life is not for the lazy.
9. Re:Efficiency??? by TWX · 2014-12-03 02:34 · Score: 1
  
  We already have extremely low friction fluid-drive connections, they're called torque converters.
  
  --
  Do not look into laser with remaining eye.
10. Re:Efficiency??? by wvmarle · 2014-12-03 02:40 · Score: 1
  
  It would work well for things that require very little force, like reorienting the solar panels or aiming the antenna
  Maybe you should look into this natural phenomena called "wind". It's there in many parts of the world. It's something that can put massive forces on things like solar panels, and to a lesser extent antennas.
11. Re: Efficiency??? by Anonymous Coward · 2014-12-03 02:56 · Score: 0
  
  Ah, yes: Space Wind. How could we forget?
12. Re:Efficiency??? by Smidge204 · 2014-12-03 05:09 · Score: 1
  
  If you couldn't move high forces with a transmission like this, then you also couldn't generate them with an electric motor, because you couldn't hope for the magnetic fields to turn the stator against high loads.
  Electric motors can stall, and when they do so they draw a terrifyingly huge amount of power compared to when they're operating properly. Providing that static torque is very expensive and often dangerous unless the motor and controls were designed for it.
  It's not that magnetic fields can't be strong enough, it's getting fields that are strong enough without additional energy input.
  =Smidge=
13. Re:Efficiency??? by drinkypoo · 2014-12-03 05:10 · Score: 1
  
  We already have extremely low friction fluid-drive connections, they're called torque converters.
  Yes, but you have to be already making use of fluid pressure for that to be worth using, and they have lots of drawbacks. Some hybrids replace the TC with an electric motor already, starting with the Honda Insight and including Subaru's hybrids. This is already a form of magnetic coupling, and the only friction comes from the bearings themselves. It is capable of doing the TC's job, plus giving full-drivetrain power — and regenerative braking.
  In an EV, obviously, we can eliminate the ICE and otherwise use basically the same system, with a larger electric motor. But as Tesla has demonstrated, it actually makes more sense to use a motor per axle, if you don't have an ICE involved.
  Torque converters are going away in favor of other solutions, because they are crappy.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
14. Re:Efficiency??? by drinkypoo · 2014-12-03 05:18 · Score: 1
  
  Electric motors can stall, and when they do so they draw a terrifyingly huge amount of power compared to when they're operating properly.
  Part of the motor controller's job is to prevent that, but it's irrelevant here, because they're using permanent magnets. The maglev bearings have to be cooled, but the part of the transmission that provides the gearing doesn't require any power at all. You design the system for the torques you're expecting to see and you get limited slip out of it for free. This part of the system could be used even without the maglev bearings, to eliminate gear friction and to prevent damage in the case of a lockup. If I were designing the system for an off-road vehicle, I'd want to have a physical clutch available as a backup in my lowest gear, but for on-road use it shouldn't be a problem at all. As long as just one axle can provide enough motive force to move the car up the steepest hills it's meant to manage, and the brakes are present to lock up any wheels which are spinning (Bosch calls this EDL, and Porsche and VW have been using it since the nineties, often with a torsen diff but sometimes just an open one) then then the rest is just tuning.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
15. Re:Efficiency??? by TubeSteak · 2014-12-03 05:21 · Score: 1
  
  The question is, how much force can it handle?
  The video says it has a max input speed of 3000 rpm and a max output torque of 3Nm (~4 ft/lbs) with a gear reduction of 1:20.
  
  --
  [Fuck Beta]
  o0t!
16. Re:Efficiency??? by Smidge204 · 2014-12-03 05:53 · Score: 1
  
  Your argument basically boils down to "since electric motors can produce high torque, then permanent magnet couplings can also provide high torque"
  My contention is you make it sound way, way simpler than it is. Also, you'll find that the really big motors are not the permanent magnet type exactly because producing a high-torque motor with permanent magnets is more difficult and expensive. It's an issue of flux density.
  I'm sure you COULD design a permanent magnet coupling for any particular purpose, but that doesn't mean it makes sense to do so.
  =Smidge=
17. Re:Efficiency??? by Anonymous Coward · 2014-12-03 06:03 · Score: 0
  
  In response to your last comment
  
  not a cure-all solution, it's just a good new option for specific applications. You won't use it to build a better crane but gyroscope flywheels could immensely benefit from that!
  We can build a Gyroscope that has absolutely no moving parts simply by using a coiled fiber optic cable. Been doing that since the 90's when I first read about it.
18. Re:Efficiency??? by drinkypoo · 2014-12-03 06:05 · Score: 1
  
  Your argument basically boils down to "since electric motors can produce high torque, then permanent magnet couplings can also provide high torque"
  Yeah, pretty much.
  
  Also, you'll find that the really big motors are not the permanent magnet type exactly because producing a high-torque motor with permanent magnets is more difficult and expensive.
  Mostly expensive.
  
  I'm sure you COULD design a permanent magnet coupling for any particular purpose, but that doesn't mean it makes sense to do so.
  Well, TFA says they did it already, and I suspect they're smarter than you are (or me, to be fair) so I suspect you're on about nothing.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
19. Re:Efficiency??? by Anonymous Coward · 2014-12-03 06:23 · Score: 0
  
  Well, TFA says they did it already,
  
  For a very limited torque...
20. Re:Efficiency??? by Anonymous Coward · 2014-12-03 06:27 · Score: 0
  
  We can build a Gyroscope that has absolutely no moving parts simply by using a coiled fiber optic cable. Been doing that since the 90's when I first read about it.
  That is great when all you need to do is detect changes in orientation, but the point of flywheels on spacecraft is to mechanically maintain and stabilize orientation without using fuel.
21. Re:Efficiency??? by Smidge204 · 2014-12-03 07:09 · Score: 1
  
  As the AC said, for a very limited torque; 15 Newton-Meters. For a sense of scale, the recommended torque on a lug nut for a car tire is typically around 8-10 times that.
  It's also under cryogenic conditions, intended for space applications, which is a rather special case (ultra-reliable under extreme environments) where it makes makes more sense to use something exotic.
  And having said that, the more I learn about it the less I'm impressed with it. Magnetic bearings are pretty old hat technologically speaking, and the harmonic drive aspect is only novel in that it uses magnetic repulsion to flex the spline cup rather than physical contact. Meh. Even their "through-wall transmission" thing is a glorified magnetic stirrer.
  =Smidge=
22. Re: Efficiency??? by Anonymous Coward · 2014-12-03 09:26 · Score: 0
  
  Fucking moron ACs...
23. Re:Efficiency??? by Sardaukar86 · 2014-12-03 09:28 · Score: 1
  
  As the AC said, for a very limited torque; 15 Newton-Meters. For a sense of scale, the recommended torque on a lug nut for a car tire is typically around 8-10 times that.
  Please forgive my ignorance Smidge but I find that number quite astounding although I have no reason to doubt your comment.
  Isn't 150NM about what a small car is putting out in terms of torque? Admittedly one (rightly or wrongly) is supposed to stand on lug nuts to tighten them properly, is this what is meant here?
  Just seems quite a lot to me with my limited understanding of the topic.
  
  --
  ..Mullah or Pope, Preacher or Poet, who was it wrote: "Give any one species too much rope and they'll fuck it up"?
24. Re:Efficiency??? by StikyPad · 2014-12-03 10:01 · Score: 1
  
  Not having to replace clutch plates, for example, might be a nice and relatively easily doable thing.
  Probably not worth it. A properly functioning clutch should have minimal parasitic loss from friction when engaged, so the only thing you're saving is the cost of replacing the clutch. Since clutches are usually easy to replace and relatively cheap, especially compared to the cost of something like this, it's probably throwing money away.
  
  --
  https://www.eff.org/https-everywhere
25. Re: Efficiency??? by SharpFang · 2014-12-03 11:10 · Score: 1
  
  Yeah, so could you give me an estimate on the massive force of solar wind pressure against solar panels of a space probe?
  Oh, wait, the linked article has it. At 1AU, typically in the range of 1–6 nanonewtons per square meter.
  Yeah, massive indeed. The bearings stand no chance.
  
  --
  45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
26. Re:Efficiency??? by Smidge204 · 2014-12-03 11:53 · Score: 1
  
  150Nm is about what a typical small car engine might be capable of at peak, but torque at the wheels would typically be greater due to gear reductions. Not really relevant, though - the torque of the engine applied to the wheels is not applied to the lug nuts on the wheels as a torque, but applied to the lugs themselves as a shear.
  Maybe imperial units will help?
  15 Newton-meters is roughly 11 foot-pounds. Most people can comfortably apply that kind of torque with a normal wrench, and that's about twice what a strong person could do with a screwdriver.
  Torque specifications for lug nuts are typically in the 80 to 120 foot-pound range, though practically nobody outside of a reputable auto shop will bother with that (and even most reputable shops will gloss over it...). Most people, including myself, either use an impact gun or step on the lug wrench, which results in slight over-tightening. Figure a 150-lb person standing on a 12" long wrench and that's 150 ft-lbs... slightly over but not too bad.
  For gasoline car engines, torque (ft-lbs) seems to always be fairly close to horsepower... so 120 ft-lbs is about right for a 120hp engine, plus or minus. It boils down to the fact that most gasoline engines are designed to run at a certain RPM, which makes the math turn out that these two metrics are often within maybe 10% of each other.
  =Smidge=
27. Re:Efficiency??? by Sardaukar86 · 2014-12-03 12:00 · Score: 1
  
  Great explanation, thank you very much. :)
  
  --
  ..Mullah or Pope, Preacher or Poet, who was it wrote: "Give any one species too much rope and they'll fuck it up"?
28. Re:Efficiency??? by ChrisMaple · 2014-12-03 12:24 · Score: 1
  
  (Hydraulic) torque converters are at very best 95% efficient, which sucks. Why do you think heavy vehicles with automatic transmissions require a separate radiator for the transmission?
  
  --
  Contribute to civilization: ari.aynrand.org/donate
29. Re:Efficiency??? by drinkypoo · 2014-12-04 01:07 · Score: 1
  
  the torque of the engine applied to the wheels is not applied to the lug nuts on the wheels as a torque, but applied to the lugs themselves as a shear.
  And that is why lug nut torque is entirely irrelevant. Guess what? Small car, flat surface, don't set the brake, you'll move the car while tightening the lug nuts. But it's still irrelevant.
  
  Torque specifications for lug nuts are typically in the 80 to 120 foot-pound range, though practically nobody outside of a reputable auto shop will bother with that (and even most reputable shops will gloss over it...)
  There is no such thing as a reputable shop which won't torque your lug nuts to specification, only idiots who can't identify a reputable shop. My tire shop always torques my lug nuts with a torque wrench, to spec, and so do I. Not doing so risks a wheel falling off.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
30. Re:Efficiency??? by rgbatduke · 2014-12-04 01:14 · Score: 1
  
  You're probably right. Although I've had a standard transmission car go through 100% of its clutch plate and they are not cheap to replace. But what is? And how many cars have standard transmissions any more? And of those, how many go through a whole clutch plate before they die from some other cause. Toyota's magnetic regenerative braking system suggests that one "can" mass produce the requisite magnetic coupling, but there probably isn't a compelling reason to do it in this case.
  
  --
  Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
31. Re:Efficiency??? by uninformedLuddite · 2014-12-04 13:45 · Score: 1
  
  You actually expect me to look up videos Myself ?
  
  --
  The new right fascists are bilingual. They speak English and Bullshit.
32. Re:Efficiency??? by SharpFang · 2014-12-05 03:57 · Score: 1
  
  The point of transmission is not only "displacement" of rotary movement but also exchange of rotation speed for momentum. So, if (as the article says) the gear ratio is 1:20, it means the load on an axis two such transmissions away will be 400 times that of a motor.
  And while, yes, the design makes the system safe against damage due to too high load, the load it can provide is still far away from load which could damage the mechanics; if the slippage was to occur at loads ten times as high, it would still be outside the self-damage zone.
  
  --
  45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
Might be a fit for EVs by drinkypoo · 2014-12-02 23:44 · Score: 2

It looks too bulky to provide a lot of gears in an automotive application, but if it could provide just two that you couldn't strip out no matter how much torque you put through them, it could be a really nice match for EVs. They would benefit from a transmission, but it's difficult for any transmission of a reasonable size to handle the output torque.

--
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
1. Re:Might be a fit for EVs by Anonymous Coward · 2014-12-03 00:01 · Score: 1
  
  Actually it is a terrible idea for an EV. Magnetic material properties limit the amount of force you can transmit across an airgap, and physics doesn't care whether this is being generated by rotating permanent magnets or electromagnets. If it made sense to put one of these on the end of your electric motor, it would make even more sense to just replace the gearbox's input rotor with an electromagnetic stator and have a direct drive motor in the first place.
  Also, one of the great things about an electric motor is that you can accurately control the torque output. It is really the most pointless application for an overload safe transmission, especially in an EV where you don't have servo type dynamic loads.
2. Re:Might be a fit for EVs by drinkypoo · 2014-12-03 00:11 · Score: 2
  
  Actually it is a terrible idea for an EV. Magnetic material properties limit the amount of force you can transmit across an airgap,
  That is a feature. You're thinking in terms of a perfect world. I guess now we know what kind of cowardice you display, coward. You're afraid to think things through completely. Guess what? Torque converters slip sometimes, too.
  
  one of the great things about an electric motor is that you can accurately control the torque output. It is really the most pointless application for an overload safe transmission
  Again, you're not living in the real world, where EVs don't have multiple gears because they destroy transmissions when we try to use them with one more complicated than a simple reduction gear. See, the problem with torque control on an electric motor isn't how rapidly you can back off the power. It's how rapidly it comes on, and how much of it there is. When the motor applies its full torque, and there is some sort of binding or resistance, the transmission gets all of that torque right away. But energy from ICEs comes in squishy packets.
  It's a feature and not a problem that this transmission will slip slightly occasionally. It will only happen when you would otherwise have been at risk of breaking something.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
3. Re:Might be a fit for EVs by Charliemopps · 2014-12-03 00:21 · Score: 4, Informative
  
  It looks too bulky to provide a lot of gears in an automotive application, but if it could provide just two that you couldn't strip out no matter how much torque you put through them, it could be a really nice match for EVs. They would benefit from a transmission, but it's difficult for any transmission of a reasonable size to handle the output torque.
  Electric cars don't need gears in the first place. The only reason we have gears in IC engines is because, 1. it would be expensive and hard to keep the engines in sync if you had a separate one for each wheel, 2. IC engines operate in most efficiently at very specific RPMs. Notice how the tachometer tends to hover around 2000 rpm as you shift gears? That's what the gears are for, to keep the engine at a constant RPM. Electric motors work just as efficiently at just about any RPM.
4. Re:Might be a fit for EVs by NoNeeeed · 2014-12-03 01:55 · Score: 1
  
  The other reason is that an ICE can't generate force when at rest (unlike an electric motor), so getting going from stationary is impossible without a clutch. That's why, if you drive a manual, the engine has to be revved and the clutch gradually engaged, bleeding power into the axels while allowing the engine to run without stalling. Engage the clutch too fast and the engine will simply stall.
  I believe External CEs like steam engines can generate force when at rest, so they don't need gearing.
  It's one of the reasons by diesel trains (and some very large vehicals) are diesel-electric. A rail engineer I used to work with told me the gearbox and clutch needed to gear down a diesel engine to the point it could start a train would be enormous, bigger than a train car. Diesel electric trains are basically diesel generators that power electric motors, which is why they are sometimes used for emergency power.
  
  --
  Paul Leader
5. Re:Might be a fit for EVs by trout007 · 2014-12-03 02:12 · Score: 1
  
  Wrong. Electric cars have plenty of gears. You need to change the relatively high RPM of an electric motor to the lower RPM of the wheels. Also if a motor is driving more than one wheel you need a differential which is full of gears.
  What you might not need is a transmission where you can actively change the gear ratio but there are plenty of gears in an electric car.
  
  --
  I love Jesus, except for his foreign policy.
6. Re:Might be a fit for EVs by Anonymous Coward · 2014-12-03 02:49 · Score: 1
  
  Actually it is a terrible idea for an EV. Magnetic material properties limit the amount of force you can transmit across an airgap,
  That is a feature. You're thinking in terms of a perfect world. I guess now we know what kind of cowardice you display, coward. You're afraid to think things through completely. Guess what? Torque converters slip sometimes, too.
  
  one of the great things about an electric motor is that you can accurately control the torque output. It is really the most pointless application for an overload safe transmission
  Again, you're not living in the real world, where EVs don't have multiple gears because they destroy transmissions when we try to use them with one more complicated than a simple reduction gear. See, the problem with torque control on an electric motor isn't how rapidly you can back off the power. It's how rapidly it comes on, and how much of it there is. When the motor applies its full torque, and there is some sort of binding or resistance, the transmission gets all of that torque right away. But energy from ICEs comes in squishy packets.
  It's a feature and not a problem that this transmission will slip slightly occasionally. It will only happen when you would otherwise have been at risk of breaking something.
  You attack my post yet leave out the most important point - that due to physical limits on attainable airgap sheer stress, the design is redundant compared to direct drive. I don't know why you left that bit out but perhaps you don't understand how magnetic systems work.
  Also your bit about torque control is plain wrong. Current is immediately and directly proportional to torque in an electric motor. If the system 'locks up' as you say, then just limit the current. Let the control software provide the 'slip' rather than having it needlessly blast torque into your gearbox so that you have to use a mechanical clutch to prevent failure.
  I suspect much of this thinking comes from old school voltage regulating motor drives where stalling would produce high torque/current only limited by the terminal resistance. Electronic control has come a long long way since then, and is very much in the real world.
7. Re:Might be a fit for EVs by Anonymous Coward · 2014-12-03 03:09 · Score: 0
  
  Also EVs don't have to eat gearboxes (the differential/final drive is a gearbox and it seems to be doing fine), it is just that Tesla was not very good at designing a reliable multi-speed one. Making one of these with low cost, weight and long life is not trivial, but they really should have been able to sort it out.
  However, in an EV you always have the option of just making the motor slightly bigger and eliminating the multi-speed gearbox. My guess is that after discovering good gearbox design was a bit more complex than they thought, Tesla decided it wasn't worth the effort for now (at higher vehicle volumes that might change). An added benefit of oversizing the motor is that you get better acceleration so it is probably a tight race as to which way to go when you consider the entire vehicle package. Again this may change as they move from luxury to commodity vehicles.
8. Re:Might be a fit for EVs by Anonymous Coward · 2014-12-03 03:30 · Score: 0
  
  Ignore drinkypoo's attacks. He/she is really smart, but if you say "pink" and drinky thinks it is "light red" you won't get "no, I think it is light red because the RGB value is ..." you will get something more like "It's light red you Communist pig! What fool you are not to see that the RGB value is..." I just prefer to assume this person is really smart but has some kind of metal/social disorder.
9. Re:Might be a fit for EVs by fnj · 2014-12-03 03:47 · Score: 2
  
  An electric car does not have to have reduction gearing at all. In fact there are electric cars that do not. Repeat, do not. Believe it. In fact you can also do away completely with mechanical brakes.
  If Tesla and GM and Nissan and others were all too timid or conservative to do it right, that is their problem.
  Now who is wrong?
10. Re:Might be a fit for EVs by a4r6 · 2014-12-03 04:02 · Score: 1
  
  I have to refute your point #1.
  
  There's no need to keep engines "in sync" when they each power their own wheel. the road does that.
  
  The only thing to watch out for would be loss of traction on a particular wheel, but traction control would not significantly more complicated with two or four drivetrains instead of one. In fact, you could do away with the wheel speed sensors and rely on relative engine rpms to determine when one has lost traction.
  
  The biggest reasons we don't have cars with multiple IC engines are:
  1. Cost
  2. Complexity (each would need its own transmission because as you mentioned, they work best at certain rpms)
  3. Efficiency at high load (two 2.0l engines will eat more gas than one 4.0l)
  4. It's unorthodox - you'd have to convince people its not stupid
  
  Honestly, I think that there is a compelling argument for making cars with multiple engines, i.e. a transverse engine for the front two wheels, and another for the back.
  
  1. you can re-use almost all of the parts from front to back, so while there are more parts, there aren't more UNIQUE parts.
  2. Efficiency at low loads (ideally done with a stop-start kind of system, you could simply leave one engine off when the extra power and traction are not needed, thus doing away with almost half your frictional losses and reciprocating mass)
  3. Redundancy - (if one engine is experiencing a failure of some kind, you have another one!)
  4. Ideal AWD! perfect front/rear torque distribution when both are running. (All other methods of torque distribution have shortcomings, whether it's by viscous clutch, eletronic clutch, clutch packs, torsen, solid coupling, whatever. There is a trade off between slip and traction, and slip is needed for a car to turn without destroying gears.)
11. Re:Might be a fit for EVs by drinkypoo · 2014-12-03 05:21 · Score: 1
  
  Now who is wrong?
  The lames who think that hubmotors are appropriate for anything more than a golf cart. Around 25 mph, the effect on unsprung mass begins to seriously affect handling. This speed is not a law of physics, it just has to do with typical wheel sizes and masses. If you could substantially knock down the mass of the stuff around the hub motor, then you could get away with it, but if you made a tire thinner then you can't handle higher speeds anyway, if you make a rim thinner it deforms, and so on.
  If all you want is to drive a golf cart or a segway, you don't need gearing. But hub motors make for shitty handling on real cars, not toys which should be driven by (and not just controlled with) pedals and a horn with a squeeze bulb.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
12. Re:Might be a fit for EVs by timeOday · 2014-12-03 05:58 · Score: 1
  
  It sounds to me like this contact-free coupling actually is basically like an electric motor - except stationary:
  
  Prototype number two is designed to be used at room temperature. In this case, the magnetic reducer sees the gear teeth replaced with permanent magnets that repel and attract each other so that "the transmission of couples and forces between the moving parts with contact is achieved."
  
  This is what an electric motor does, except some mechanism (such as brushes) enables and disables the magnets in phase, such that the armiture is always magnetically attracted forwards, in the desired direction of rotation.
13. Re:Might be a fit for EVs by Anonymous Coward · 2014-12-03 06:38 · Score: 0
  
  The sync part is true for ICE, a car magazine 30 years ago or so put a second engine in a Honda (I think) to prove it. They were worried about that when they built it, turns out it IS a non-issue. I remember it cause I was thinking how awesome our Phoenix would be with a 2nd engine :)
  2x HP and 1.5x the weight plus AWD.
14. Re:Might be a fit for EVs by holmstar · 2014-12-03 07:46 · Score: 1
  
  I agree on the unsprung mass issue, but I wonder if it would be possible to use a linear motor in place of a shock absorber to counter some of the negative handling effects. I doubt it would be able to make up for it completely, but I imagine it could help quite a bit.
15. Re:Might be a fit for EVs by fnj · 2014-12-03 08:37 · Score: 1
  
  "But unsprung weight" is a tired old preconception. Maybe if you bothered exploring the references provided and elsewhere you would be relieved of some of your misconceptions.
  Protean Electric tackles the unsprung-mass 'myth' of in-wheel motors
  Heresy Unsprung, Lotus Engineering: Unsprung Weight Doesn’t Really Matter Much[The Truth]
16. Re:Might be a fit for EVs by Anonymous Coward · 2014-12-03 09:13 · Score: 0
  
  That looks like the best confirmation of the problem, instead of debunking it. They needed a Focus RS suspension instead of the regular Focus just to cancel out the extra unsprung weight of the wheels - and part of the premium price of the Focus RS suspension is its use of lightweight materials so the actual increase in unsprung mass wasn't as great as claimed. Of course engineers can fix the problem given enough money.
  The reality is that when a wheel hits a bump, all the unsprung mass of the wheel suddenly undergoes a large acceleration. 'That's pretty much the definition of unsprung weight. And with a fixed, F=m*a also means the force on the wheel is proportional to the unsprung weight. This is 17th century physics.
17. Re:Might be a fit for EVs by fnj · 2014-12-03 14:18 · Score: 1
  
  That looks like the best confirmation of the problem, instead of debunking it. They needed a Focus RS suspension instead of the regular Focus just to cancel out the extra unsprung weight of the wheels - and part of the premium price of the Focus RS suspension is its use of lightweight materials so the actual increase in unsprung mass wasn't as great as claimed. Of course engineers can fix the problem given enough money.
  The reality is that when a wheel hits a bump, all the unsprung mass of the wheel suddenly undergoes a large acceleration. 'That's pretty much the definition of unsprung weight. And with a fixed, F=m*a also means the force on the wheel is proportional to the unsprung weight. This is 17th century physics.
  Welcome to the conversation, intellectus superiosa slashdotus. Confronted with the results of actual engineering studies by experts in the field, which you could actually learn something from, you repeat the same tired old preconceived crap with no analysis whatsoever to support it.
18. Re:Might be a fit for EVs by drinkypoo · 2014-12-04 01:11 · Score: 1
  
  "But unsprung weight" is a tired old preconception. Maybe if you bothered exploring the references provided and elsewhere you would be relieved of some of your misconceptions.
  My. Asshole. That is complete fucking bullshit, and if you had any relevant experience with the subject at hand, you'd know that. I've personally felt the difference in ground contact made by removing just fifteen pounds per wheel, and it is massive. These assholes (who are selling something, you rube) are telling us that adding sixty pounds won't negatively impact handling. But hey, from your own first citation:
  
  Hereâ(TM)s what Steve Williams of Lotus Engineering said:
  
  Whilst it is true to say that the vehicle dynamic performance was degraded by the increase in unsprung mass, the degree to which this was noticeable was small and could be said to have moved the overall dynamic performance of the test vehicle from class leading to mid class.
  So just to be clear, even in the hands of Lotus, unsprung mass negatively effects handling sufficiently to take a car from "best in class" to "middle of the class". And you suggest it doesn't affect handling? Perhaps you should read your citations.
  Here's something you can take home from personal experience: I went from 21lb to 11lb wheels, and chose a new tire 10mm narrower because the tire weight dropped 4lb from 25 to 21. The car became immediately easier to control on broken pavement, especially while pushing around a corner. It's not rocket surgery to figure out why. In a perfect world the spring rates would actually be different during compression and rebound, and you can only fake that effect so much with damping.
  TL;DR: Your first citation says precisely the opposite of what you want it to say.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
19. Re:Might be a fit for EVs by drinkypoo · 2014-12-04 20:36 · Score: 1
  
  Confronted with the results of actual engineering studies by experts in the field, which you could actually learn something from,
  
  You failed to either read or comprehend your own citation, which says precisely the opposite of what you want it to say. Then you belittled others for it. Congratulations!
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Efficiency??? by Anonymous Coward · 2014-12-03 00:49 · Score: 0

Sounds great but how Efficient is it? AKA cars can't afford to lose 10% more power over conventional gears...
FTFY
mod down by Anonymous Coward · 2014-12-03 01:06 · Score: -1

the public eye: as poosible? How EFNet servers. GNAA on slashdot, a popular 'news And enjoy all the
FYI: Milk Float by camperdave · 2014-12-03 01:54 · Score: 2

For the confused: A milk float is a small flatbed vehicle for delivering milk, and not an alternative name for a milkshake.

--
When our name is on the back of your car, we're behind you all the way!
I'm confused: Loses its teeth? by camperdave · 2014-12-03 03:12 · Score: 1

I'm confused. Doesn't "loses its teeth" mean that it has failed and/or become less powerful? I was expecting to hear how the research had failed.

--
When our name is on the back of your car, we're behind you all the way!
1. Re:I'm confused: Loses its teeth? by Anonymous Coward · 2014-12-03 04:20 · Score: 0
  
  I'm confused. Doesn't "loses its teeth" mean that it has failed and/or become less powerful? I was expecting to hear how the research had failed.
  teeth as in gears or cog wheel
2. Re:I'm confused: Loses its teeth? by camperdave · 2014-12-03 04:24 · Score: 1
  
  When a gear or cog-wheel loses its teeth, it also becomes less powerful, does it not?
  
  --
  When our name is on the back of your car, we're behind you all the way!
3. Re:I'm confused: Loses its teeth? by Anonymous Coward · 2014-12-03 04:49 · Score: 0
  
  This drive has no gears with teeth literary. Its movement is based in magnets, not the teeth in gears.
4. Re:I'm confused: Loses its teeth? by Anonymous Coward · 2014-12-03 04:54 · Score: 0
  
  These gears literally have no teeth man!
5. Re:I'm confused: Loses its teeth? by Anonymous Coward · 2014-12-03 06:55 · Score: 0
  
  It also have no teeths to lose!
  My Duck Loses Its Teeth.
6. Re:I'm confused: Loses its teeth? by holmstar · 2014-12-03 07:52 · Score: 1
  
  Really, they replaced the metal teeth with magnetic teeth.
The killer app for magnetic transmissions by benjfowler · 2014-12-03 03:23 · Score: 1

Deep-space power systems to run big space probes like Galileo and Cassini are nuclear powered, but use incredibly inefficient RTG... which are only 1-2% efficient.
Somebody (US Department of Energy) was looking to boost this by using a plutonium heat source to drive a Sterling engine coupled to a generator. The problem with this arrangement is that moving parts wear out.
It just so happens that deep space is very cold...
Still need transmission in cars by Chirs · 2014-12-03 03:45 · Score: 1

Just like IC motors, electric motors do not provide constant power/torque across their whole speed range. There's a reason why cordless drills often have two or three speed transmissions.
A typical universal motor generates max torque just before it stalls, and relatively little torque at high speed. This is great for fast acceleration from a standstill, not so much for trying to hit maximum speed with just a single-speed gearbox.
1. Re:Still need transmission in cars by holmstar · 2014-12-03 07:50 · Score: 1
  
  I wonder how high speed electric trains are geared? Maybe they have more than one motor on the same axle, wound for different ranges of speed?
Smoothing out diesel Aircraft engines? by chaim79 · 2014-12-03 03:55 · Score: 2

This should really be looked at by those producing Diesel engines for Airplanes.
The biggest problem tinker's face when trying to put a Diesel engine on an airplane is that the Diesel has very massive "power surges" each time a cylinder fires, and a nasty power "stall" when it's compressing a cylinder. This isn't a huge deal with the other applications of Diesel engines, they just add mass to the fly-wheel and transmission and that takes care of it. In Airplanes however, the mass costs too much (in terms of airplane weight) so they try to reduce it as much as possible, however if you reduce it too much the propeller is literally torn apart by the surges and stalls. Early tests had the propeller lasting only hours when running on a 4 or 6 cylinder diesel. If there is a reduction drive on it to bring the RPMs further down they too like to self destruct with a Diesel.
If they could use a low-weight magnetic coupler to absorb the surges and stalls and provide smooth power that would solve the biggest problem putting a diesel on an airplane and would really boost that market!

--
DEMETRIUS: Villain, what hast thou done?
AARON: Villain, I have done thy mother.
Shakespeare invents 'your mom'
1. Re:Smoothing out diesel Aircraft engines? by holmstar · 2014-12-03 07:59 · Score: 1
  
  I wonder whether the magnetic coupler would be any lighter than a larger flywheel. Also, couldn't the slipping of the coupler set up harmonic vibrations in the prop as well? (I imagine a magnetic coupler would slip in a notch-y fashion.)
Cost? by dumky2 · 2014-12-03 06:43 · Score: 1

Look, this great shiny technology. Oops, it's uneconomical...
Costs are an important question as this story happens quite often (mag trains anyone?).
For space projects the cost may not matter, since it's paid for by taxpayers. But for applications for the rest of us making this affordable is as important, if not more.

--
These comments are mine; I do not speak for my employer.
Story source by Anonymous Coward · 2014-12-03 15:17 · Score: 0

Hey, how about posting where this source was quoted (verbatim) from...? Especially as the title is pilfered directly from the original story!
http://www.gizmag.com/frictionless-superconductor-magnetic-levitating-gear-system/35005/