Posted by Androcles on June 5, 2009, 2:35 pm
> On Fri, 05 Jun 2009 09:48:31 -0700, tgdenning wrote:
>>> On 6/5/09 7:52 AM, in article
>>> a187370d-0d8a-4565-8cb8-407364942...@d31g2000vbm.googlegroups.com,
>>>
>>>
>>>
>>> >> tgdenn...@earthlink.net wrote:
>>>
>>> >>>> It is very simple. Think of motors in a wheel bouncing down the
>>> >>>> road. Heavy is not good because too much energy is fed right back
>>> >>>> to them because the suspension cannot transfer it quickly enough
>>> >>>> to some putative absorber in the chassis.
>>>
>>> >>>> However, if one distributes the total desired power among four
>>> >>>> wheels, then each will be lighter and life is good again.
>>>
>>> >>>> My friend, I have been building race setups for forty years. I
>>> >>>> know this shit.
>>>
>>> >>> Glad to hear it. I like to talk to people who know what they are
>>> >>> talking about. However, my point does not change---the benefit of 4
>>> >>> electric motors is pretty much the same even if they are 'mounted
>>> >>> inboard'. I am not interested in worrying about what you call them.
>>>
>>> >> Never seen "inboard" mounted wheels on an autombile. What would they
>>> >> look like?
>>>
>>> >http://teslamotorsclub.com/technical/303-hub-motors-dual-motors.html
>>>
>>> That is not an inboard hub motor. It is not a hub motor at all. It is a
>>> perfectly conventional motor. A hub motor is inside the wheel, not
>>> just something that drives the hub. There are no motors or engines that
>>> drive the wheel anywhere but to the hub. None drive at the rim of the
>>> wheel (except for a couple exotic show motorcycles that are
>>> impractical. Citations available.)
>>
>> You lost me there---I'm in favor of using perfectly conventional motors
>> if that works.
>>
>>
>>> If I were home I'd shoot some pics of the Porsche's IRS and you would
>>> see it's connected to the transmission just like that illustration done
>>> by the would-be impressionistic, unlearned contributor to the site in
>>> question.
>>>
>>>
>> The picture is just so people can visualize the possible configuration.
>> I don't see anything wrong with it.
>>
>>
>>> So, let's stick to real-world terms. I would not use the post in
>>> question as a source of any authority.
>>>
>>> > Scroll down to number 8 I think. I would dispense with disc brakes
>>> > on the wheel and put some very simple parking-brake device on the
>>> > inboard side as a 'final ultimate' emergency stopping option, relying
>>> > on electric braking.
>>>
>>> Old hat. We have been mounting disc brakes on drive shafts for many
>>> years. I think Lotus does it. I have done it. You can't turn a disc
>>> brake into a generator. Its lack of a flywheel effect and radius make
>>> it impractical, and also consider that all electric motors are also
>>> generators, but not particularly powerful.
>>
>> Again you've lost me---you are obviously misinterpreting what I said.
>> Braking is done by the electric motor; for most of the braking period
>> you are recovering the kinetic energy, which is why it is called
>> regenerative braking. The ultimate implementation would have no disc
>> brakes at all. If you need further explanation please let me know.
> Motor/generators are transducers, not brakes. That means you can only
> slow down, not come to a complete stop. If the electronic controller
> failed, you couldn't even slow down. How big a market do you expect for
> cars without brakes?
> Remember, everything looks easy to the guy who doesn't actually have to
> do it.
Don't know much about stepper motors, do you?
http://en.wikipedia.org/wiki/Stepper_motor
However, any vehicle would have brakes for parking if nothing else.
Posted by Bill Ward on June 5, 2009, 3:35 pm
On Fri, 05 Jun 2009 19:35:02 +0100, Androcles wrote:
>> On Fri, 05 Jun 2009 09:48:31 -0700, tgdenning wrote:
>>
>>>> On 6/5/09 7:52 AM, in article
>>>> a187370d-0d8a-4565-8cb8-407364942...@d31g2000vbm.googlegroups.com,
>>>>
>>>>
>>>>
>>>> >> tgdenn...@earthlink.net wrote:
>>>>
>>>> >>>> It is very simple. Think of motors in a wheel bouncing down the
>>>> >>>> road. Heavy is not good because too much energy is fed right
>>>> >>>> back to them because the suspension cannot transfer it quickly
>>>> >>>> enough to some putative absorber in the chassis.
>>>>
>>>> >>>> However, if one distributes the total desired power among four
>>>> >>>> wheels, then each will be lighter and life is good again.
>>>>
>>>> >>>> My friend, I have been building race setups for forty years. I
>>>> >>>> know this shit.
>>>>
>>>> >>> Glad to hear it. I like to talk to people who know what they are
>>>> >>> talking about. However, my point does not change---the benefit of
>>>> >>> 4 electric motors is pretty much the same even if they are
>>>> >>> 'mounted inboard'. I am not interested in worrying about what you
>>>> >>> call them.
>>>>
>>>> >> Never seen "inboard" mounted wheels on an autombile. What would
>>>> >> they look like?
>>>>
>>>> >http://teslamotorsclub.com/technical/303-hub-motors-dual-motors.html
>>>>
>>>> That is not an inboard hub motor. It is not a hub motor at all. It is
>>>> a perfectly conventional motor. A hub motor is inside the wheel, not
>>>> just something that drives the hub. There are no motors or engines
>>>> that drive the wheel anywhere but to the hub. None drive at the rim
>>>> of the wheel (except for a couple exotic show motorcycles that are
>>>> impractical. Citations available.)
>>>
>>> You lost me there---I'm in favor of using perfectly conventional
>>> motors if that works.
>>>
>>>
>>>> If I were home I'd shoot some pics of the Porsche's IRS and you would
>>>> see it's connected to the transmission just like that illustration
>>>> done by the would-be impressionistic, unlearned contributor to the
>>>> site in question.
>>>>
>>>>
>>> The picture is just so people can visualize the possible
>>> configuration. I don't see anything wrong with it.
>>>
>>>
>>>> So, let's stick to real-world terms. I would not use the post in
>>>> question as a source of any authority.
>>>>
>>>> > Scroll down to number 8 I think. I would dispense with disc brakes
>>>> > on the wheel and put some very simple parking-brake device on the
>>>> > inboard side as a 'final ultimate' emergency stopping option,
>>>> > relying on electric braking.
>>>>
>>>> Old hat. We have been mounting disc brakes on drive shafts for many
>>>> years. I think Lotus does it. I have done it. You can't turn a disc
>>>> brake into a generator. Its lack of a flywheel effect and radius make
>>>> it impractical, and also consider that all electric motors are also
>>>> generators, but not particularly powerful.
>>>
>>> Again you've lost me---you are obviously misinterpreting what I said.
>>> Braking is done by the electric motor; for most of the braking period
>>> you are recovering the kinetic energy, which is why it is called
>>> regenerative braking. The ultimate implementation would have no disc
>>> brakes at all. If you need further explanation please let me know.
>>
>> Motor/generators are transducers, not brakes. That means you can only
>> slow down, not come to a complete stop. If the electronic controller
>> failed, you couldn't even slow down. How big a market do you expect
>> for cars without brakes?
>>
>> Remember, everything looks easy to the guy who doesn't actually have to
>> do it.
>
> Don't know much about stepper motors, do you?
Well, I've designed control systems and drivers for them, but I haven't
ever seen one used for vehicle propulsion or regeneration. Please tell
us more about that. An example or app note would be nice. I could think
of several uses for a nice four quadrant stepper system.
> http://en.wikipedia.org/wiki/Stepper_motor
>
> However, any vehicle would have brakes for parking if nothing else.
The question was about the size of the market. I'd want disk brakes, or
equivalent, capable of several reliable maximum emergency stops, and I
don't think I'm alone in that. Call me old fashioned...
Posted by Androcles on June 5, 2009, 5:30 pm
> On Fri, 05 Jun 2009 19:35:02 +0100, Androcles wrote:
>>> On Fri, 05 Jun 2009 09:48:31 -0700, tgdenning wrote:
>>>
>>>>> On 6/5/09 7:52 AM, in article
>>>>> a187370d-0d8a-4565-8cb8-407364942...@d31g2000vbm.googlegroups.com,
>>>>>
>>>>>
>>>>>
>>>>> >> tgdenn...@earthlink.net wrote:
>>>>>
>>>>> >>>> It is very simple. Think of motors in a wheel bouncing down the
>>>>> >>>> road. Heavy is not good because too much energy is fed right
>>>>> >>>> back to them because the suspension cannot transfer it quickly
>>>>> >>>> enough to some putative absorber in the chassis.
>>>>>
>>>>> >>>> However, if one distributes the total desired power among four
>>>>> >>>> wheels, then each will be lighter and life is good again.
>>>>>
>>>>> >>>> My friend, I have been building race setups for forty years. I
>>>>> >>>> know this shit.
>>>>>
>>>>> >>> Glad to hear it. I like to talk to people who know what they are
>>>>> >>> talking about. However, my point does not change---the benefit of
>>>>> >>> 4 electric motors is pretty much the same even if they are
>>>>> >>> 'mounted inboard'. I am not interested in worrying about what you
>>>>> >>> call them.
>>>>>
>>>>> >> Never seen "inboard" mounted wheels on an autombile. What would
>>>>> >> they look like?
>>>>>
>>>>> >http://teslamotorsclub.com/technical/303-hub-motors-dual-motors.html
>>>>>
>>>>> That is not an inboard hub motor. It is not a hub motor at all. It is
>>>>> a perfectly conventional motor. A hub motor is inside the wheel, not
>>>>> just something that drives the hub. There are no motors or engines
>>>>> that drive the wheel anywhere but to the hub. None drive at the rim
>>>>> of the wheel (except for a couple exotic show motorcycles that are
>>>>> impractical. Citations available.)
>>>>
>>>> You lost me there---I'm in favor of using perfectly conventional
>>>> motors if that works.
>>>>
>>>>
>>>>> If I were home I'd shoot some pics of the Porsche's IRS and you would
>>>>> see it's connected to the transmission just like that illustration
>>>>> done by the would-be impressionistic, unlearned contributor to the
>>>>> site in question.
>>>>>
>>>>>
>>>> The picture is just so people can visualize the possible
>>>> configuration. I don't see anything wrong with it.
>>>>
>>>>
>>>>> So, let's stick to real-world terms. I would not use the post in
>>>>> question as a source of any authority.
>>>>>
>>>>> > Scroll down to number 8 I think. I would dispense with disc brakes
>>>>> > on the wheel and put some very simple parking-brake device on the
>>>>> > inboard side as a 'final ultimate' emergency stopping option,
>>>>> > relying on electric braking.
>>>>>
>>>>> Old hat. We have been mounting disc brakes on drive shafts for many
>>>>> years. I think Lotus does it. I have done it. You can't turn a disc
>>>>> brake into a generator. Its lack of a flywheel effect and radius make
>>>>> it impractical, and also consider that all electric motors are also
>>>>> generators, but not particularly powerful.
>>>>
>>>> Again you've lost me---you are obviously misinterpreting what I said.
>>>> Braking is done by the electric motor; for most of the braking period
>>>> you are recovering the kinetic energy, which is why it is called
>>>> regenerative braking. The ultimate implementation would have no disc
>>>> brakes at all. If you need further explanation please let me know.
>>>
>>> Motor/generators are transducers, not brakes. That means you can only
>>> slow down, not come to a complete stop. If the electronic controller
>>> failed, you couldn't even slow down. How big a market do you expect
>>> for cars without brakes?
>>>
>>> Remember, everything looks easy to the guy who doesn't actually have to
>>> do it.
>>
>> Don't know much about stepper motors, do you?
> Well, I've designed control systems and drivers for them, but I haven't
> ever seen one used for vehicle propulsion or regeneration. Please tell
> us more about that. An example or app note would be nice.
Just because you've never seen it doesn't make it a negative requirement,
the wheel is redesigned for every new model of car. ICEs are redesigned
and improved constantly, why not electric motors?
What's wrong with a bicycle wheel with alternate permanent magnets
around the rim and a horseshoe stator with a single coil to drive them,
fitted like a caliper brake?
http://homepages.nyu.edu/~jh15/bikes/images/stdreach.jpg
Speed control is merely frequency control, you can get the magnets
by recycling old hard drives, the magnets in those are very strong.
Embed the magnets in a solid tyre or fit them to the spokes.
Cheap and super simple, easy to fit, no problem with torque.
> I could think
> of several uses for a nice four quadrant stepper system.
Such as regenerative braking, perhaps?
Oh wait, you are against that idea, right?
>> http://en.wikipedia.org/wiki/Stepper_motor
>>
>> However, any vehicle would have brakes for parking if nothing else.
> The question was about the size of the market. I'd want disk brakes, or
> equivalent, capable of several reliable maximum emergency stops, and I
> don't think I'm alone in that. Call me old fashioned...
Nothing wrong with belt and suspenders or wearing a parachute if you plan
on strapping a military jet to your arse and jumping up the air.
But the real solution is rail; the infrastructure is mostly in place, its
cheaper
than road beds, easily electrified and vehicles can be individually
controlled
and navigated by computer, eliminating the train. You load your vegetables
on a truck and send it direct to destination, at night, phasing out 18
wheelers.
Who needs truck drivers anyway? Re-employ them as maintenance crews.
If you want to go somewhere you call a rail taxi, board it and the computer
takes you to your destination. Or you buy your own computerized rail
vehicle.
Leave the freeways for those that want to kill themselves with ICEs.
Size of market? The whole damn world.
Can it be done? Cities had trams, computers are cheap, cell phones...
of course it can. Breakdown? push the vehicle off the main rails into a
siding
and send a repair crew with a tow truck.
Posted by Bill Ward on June 5, 2009, 7:52 pm
On Fri, 05 Jun 2009 22:30:02 +0100, Androcles wrote:
>> On Fri, 05 Jun 2009 19:35:02 +0100, Androcles wrote:
>>
>>>> On Fri, 05 Jun 2009 09:48:31 -0700, tgdenning wrote:
>>>>
>>>>>> On 6/5/09 7:52 AM, in article
>>>>>> a187370d-0d8a-4565-8cb8-407364942...@d31g2000vbm.googlegroups.com,
>>>>>>
>>>>>>
>>>>>>
>>>>>> >> tgdenn...@earthlink.net wrote:
>>>>>>
>>>>>> >>>> It is very simple. Think of motors in a wheel bouncing down
>>>>>> >>>> the road. Heavy is not good because too much energy is fed
>>>>>> >>>> right back to them because the suspension cannot transfer it
>>>>>> >>>> quickly enough to some putative absorber in the chassis.
>>>>>>
>>>>>> >>>> However, if one distributes the total desired power among four
>>>>>> >>>> wheels, then each will be lighter and life is good again.
>>>>>>
>>>>>> >>>> My friend, I have been building race setups for forty years. I
>>>>>> >>>> know this shit.
>>>>>>
>>>>>> >>> Glad to hear it. I like to talk to people who know what they
>>>>>> >>> are talking about. However, my point does not change---the
>>>>>> >>> benefit of 4 electric motors is pretty much the same even if
>>>>>> >>> they are 'mounted inboard'. I am not interested in worrying
>>>>>> >>> about what you call them.
>>>>>>
>>>>>> >> Never seen "inboard" mounted wheels on an autombile. What would
>>>>>> >> they look like?
>>>>>>
>>>>>> >http://teslamotorsclub.com/technical/303-hub-motors-dual-
motors.html
>>>>>>
>>>>>> That is not an inboard hub motor. It is not a hub motor at all. It
>>>>>> is a perfectly conventional motor. A hub motor is inside the wheel,
>>>>>> not just something that drives the hub. There are no motors or
>>>>>> engines that drive the wheel anywhere but to the hub. None drive at
>>>>>> the rim of the wheel (except for a couple exotic show motorcycles
>>>>>> that are impractical. Citations available.)
>>>>>
>>>>> You lost me there---I'm in favor of using perfectly conventional
>>>>> motors if that works.
>>>>>
>>>>>
>>>>>> If I were home I'd shoot some pics of the Porsche's IRS and you
>>>>>> would see it's connected to the transmission just like that
>>>>>> illustration done by the would-be impressionistic, unlearned
>>>>>> contributor to the site in question.
>>>>>>
>>>>>>
>>>>> The picture is just so people can visualize the possible
>>>>> configuration. I don't see anything wrong with it.
>>>>>
>>>>>
>>>>>> So, let's stick to real-world terms. I would not use the post in
>>>>>> question as a source of any authority.
>>>>>>
>>>>>> > Scroll down to number 8 I think. I would dispense with disc
>>>>>> > brakes on the wheel and put some very simple parking-brake device
>>>>>> > on the inboard side as a 'final ultimate' emergency stopping
>>>>>> > option, relying on electric braking.
>>>>>>
>>>>>> Old hat. We have been mounting disc brakes on drive shafts for many
>>>>>> years. I think Lotus does it. I have done it. You can't turn a disc
>>>>>> brake into a generator. Its lack of a flywheel effect and radius
>>>>>> make it impractical, and also consider that all electric motors are
>>>>>> also generators, but not particularly powerful.
>>>>>
>>>>> Again you've lost me---you are obviously misinterpreting what I
>>>>> said. Braking is done by the electric motor; for most of the braking
>>>>> period you are recovering the kinetic energy, which is why it is
>>>>> called regenerative braking. The ultimate implementation would have
>>>>> no disc brakes at all. If you need further explanation please let
>>>>> me know.
>>>>
>>>> Motor/generators are transducers, not brakes. That means you can only
>>>> slow down, not come to a complete stop. If the electronic controller
>>>> failed, you couldn't even slow down. How big a market do you expect
>>>> for cars without brakes?
>>>>
>>>> Remember, everything looks easy to the guy who doesn't actually have
>>>> to do it.
>>>
>>> Don't know much about stepper motors, do you?
>>
>> Well, I've designed control systems and drivers for them, but I haven't
>> ever seen one used for vehicle propulsion or regeneration. Please tell
>> us more about that. An example or app note would be nice.
>
> Just because you've never seen it doesn't make it a negative
> requirement, the wheel is redesigned for every new model of car. ICEs
> are redesigned and improved constantly, why not electric motors?
>
> What's wrong with a bicycle wheel with alternate permanent magnets
> around the rim and a horseshoe stator with a single coil to drive them,
> fitted like a caliper brake?
>
> http://homepages.nyu.edu/~jh15/bikes/images/stdreach.jpg
>
> Speed control is merely frequency control, you can get the magnets by
> recycling old hard drives, the magnets in those are very strong.
> Embed the magnets in a solid tyre or fit them to the spokes.
> Cheap and super simple, easy to fit, no problem with torque.
How is that different from a multipole PM motor? Once you learn some
physics, you may be able to put your imagination to practical use. Until
then, it appears it will mostly provide entertainment.
>> I could think of several uses for a nice four quadrant stepper system.
>
> Such as regenerative braking, perhaps? Oh wait, you are against that
> idea, right?
Not at all. I'm just waiting for you to explain how to do it with a
stepper motor. I don't think it's in the wiki, so you may have to
actually think realistically about the problem.
>>> http://en.wikipedia.org/wiki/Stepper_motor
>>>
>>> However, any vehicle would have brakes for parking if nothing else.
>>
>> The question was about the size of the market. I'd want disk brakes,
>> or equivalent, capable of several reliable maximum emergency stops, and
>> I don't think I'm alone in that. Call me old fashioned...
>
> Nothing wrong with belt and suspenders or wearing a parachute if you
> plan on strapping a military jet to your arse and jumping up the air.
Or driving at 80 on the freeway. You do know, don't you, that nearly all
vehicle hydraulic brake systems are actually two redundant systems? Most
people consider brake reliability important.
>
> But the real solution is rail; the infrastructure is mostly in place,
> its cheaper
> than road beds, easily electrified and vehicles can be individually
> controlled
> and navigated by computer, eliminating the train. You load your
> vegetables on a truck and send it direct to destination, at night,
> phasing out 18 wheelers.
It sounds easy, until you start to understand some of what's involved.
But dream on, you'll never be the one actually expected to do it.
> Who needs truck drivers anyway? Re-employ them as maintenance crews.
>
> If you want to go somewhere you call a rail taxi, board it and the
> computer takes you to your destination. Or you buy your own computerized
> rail vehicle.
> Leave the freeways for those that want to kill themselves with ICEs.
> Size of market? The whole damn world. Can it be done? Cities had trams,
> computers are cheap, cell phones... of course it can. Breakdown? push
> the vehicle off the main rails into a siding
> and send a repair crew with a tow truck.
Using the rails? Or do you plan to still have roads for when you really
need something to work?
Posted by Androcles on June 5, 2009, 10:05 pm
> On Fri, 05 Jun 2009 22:30:02 +0100, Androcles wrote:
>>> On Fri, 05 Jun 2009 19:35:02 +0100, Androcles wrote:
>>>
>>>>> On Fri, 05 Jun 2009 09:48:31 -0700, tgdenning wrote:
>>>>>
>>>>>>> On 6/5/09 7:52 AM, in article
>>>>>>> a187370d-0d8a-4565-8cb8-407364942...@d31g2000vbm.googlegroups.com,
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> >> tgdenn...@earthlink.net wrote:
>>>>>>>
>>>>>>> >>>> It is very simple. Think of motors in a wheel bouncing down
>>>>>>> >>>> the road. Heavy is not good because too much energy is fed
>>>>>>> >>>> right back to them because the suspension cannot transfer it
>>>>>>> >>>> quickly enough to some putative absorber in the chassis.
>>>>>>>
>>>>>>> >>>> However, if one distributes the total desired power among four
>>>>>>> >>>> wheels, then each will be lighter and life is good again.
>>>>>>>
>>>>>>> >>>> My friend, I have been building race setups for forty years. I
>>>>>>> >>>> know this shit.
>>>>>>>
>>>>>>> >>> Glad to hear it. I like to talk to people who know what they
>>>>>>> >>> are talking about. However, my point does not change---the
>>>>>>> >>> benefit of 4 electric motors is pretty much the same even if
>>>>>>> >>> they are 'mounted inboard'. I am not interested in worrying
>>>>>>> >>> about what you call them.
>>>>>>>
>>>>>>> >> Never seen "inboard" mounted wheels on an autombile. What would
>>>>>>> >> they look like?
>>>>>>>
>>>>>>> >http://teslamotorsclub.com/technical/303-hub-motors-dual-
> motors.html
>>>>>>>
>>>>>>> That is not an inboard hub motor. It is not a hub motor at all. It
>>>>>>> is a perfectly conventional motor. A hub motor is inside the wheel,
>>>>>>> not just something that drives the hub. There are no motors or
>>>>>>> engines that drive the wheel anywhere but to the hub. None drive at
>>>>>>> the rim of the wheel (except for a couple exotic show motorcycles
>>>>>>> that are impractical. Citations available.)
>>>>>>
>>>>>> You lost me there---I'm in favor of using perfectly conventional
>>>>>> motors if that works.
>>>>>>
>>>>>>
>>>>>>> If I were home I'd shoot some pics of the Porsche's IRS and you
>>>>>>> would see it's connected to the transmission just like that
>>>>>>> illustration done by the would-be impressionistic, unlearned
>>>>>>> contributor to the site in question.
>>>>>>>
>>>>>>>
>>>>>> The picture is just so people can visualize the possible
>>>>>> configuration. I don't see anything wrong with it.
>>>>>>
>>>>>>
>>>>>>> So, let's stick to real-world terms. I would not use the post in
>>>>>>> question as a source of any authority.
>>>>>>>
>>>>>>> > Scroll down to number 8 I think. I would dispense with disc
>>>>>>> > brakes on the wheel and put some very simple parking-brake device
>>>>>>> > on the inboard side as a 'final ultimate' emergency stopping
>>>>>>> > option, relying on electric braking.
>>>>>>>
>>>>>>> Old hat. We have been mounting disc brakes on drive shafts for many
>>>>>>> years. I think Lotus does it. I have done it. You can't turn a disc
>>>>>>> brake into a generator. Its lack of a flywheel effect and radius
>>>>>>> make it impractical, and also consider that all electric motors are
>>>>>>> also generators, but not particularly powerful.
>>>>>>
>>>>>> Again you've lost me---you are obviously misinterpreting what I
>>>>>> said. Braking is done by the electric motor; for most of the braking
>>>>>> period you are recovering the kinetic energy, which is why it is
>>>>>> called regenerative braking. The ultimate implementation would have
>>>>>> no disc brakes at all. If you need further explanation please let
>>>>>> me know.
>>>>>
>>>>> Motor/generators are transducers, not brakes. That means you can only
>>>>> slow down, not come to a complete stop. If the electronic controller
>>>>> failed, you couldn't even slow down. How big a market do you expect
>>>>> for cars without brakes?
>>>>>
>>>>> Remember, everything looks easy to the guy who doesn't actually have
>>>>> to do it.
>>>>
>>>> Don't know much about stepper motors, do you?
>>>
>>> Well, I've designed control systems and drivers for them, but I haven't
>>> ever seen one used for vehicle propulsion or regeneration. Please tell
>>> us more about that. An example or app note would be nice.
>>
>> Just because you've never seen it doesn't make it a negative
>> requirement, the wheel is redesigned for every new model of car. ICEs
>> are redesigned and improved constantly, why not electric motors?
>>
>> What's wrong with a bicycle wheel with alternate permanent magnets
>> around the rim and a horseshoe stator with a single coil to drive them,
>> fitted like a caliper brake?
>>
>> http://homepages.nyu.edu/~jh15/bikes/images/stdreach.jpg
>>
>> Speed control is merely frequency control, you can get the magnets by
>> recycling old hard drives, the magnets in those are very strong.
>> Embed the magnets in a solid tyre or fit them to the spokes.
>> Cheap and super simple, easy to fit, no problem with torque.
> How is that different from a multipole PM motor? Once you learn some
> physics, you may be able to put your imagination to practical use. Until
> then, it appears it will mostly provide entertainment.
Bwhahahahahaha!
Pissed off because you've never been practical, huh?
>>> I could think of several uses for a nice four quadrant stepper system.
>>
>> Such as regenerative braking, perhaps? Oh wait, you are against that
>> idea, right?
> Not at all. I'm just waiting for you to explain how to do it with a
> stepper motor. I don't think it's in the wiki, so you may have to
> actually think realistically about the problem.
>>>> http://en.wikipedia.org/wiki/Stepper_motor
>>>>
>>>> However, any vehicle would have brakes for parking if nothing else.
>>>
>>> The question was about the size of the market. I'd want disk brakes,
>>> or equivalent, capable of several reliable maximum emergency stops, and
>>> I don't think I'm alone in that. Call me old fashioned...
>>
>> Nothing wrong with belt and suspenders or wearing a parachute if you
>> plan on strapping a military jet to your arse and jumping up the air.
> Or driving at 80 on the freeway. You do know, don't you, that nearly all
> vehicle hydraulic brake systems are actually two redundant systems? Most
> people consider brake reliability important.
You do know, don't you, that nearly all aircraft hydraulic systems are
actually never used for brakes?
Should you ever learn engineering you may never be able to put your
pathetic lack of imagination to practical use. It appears it will mostly
provide mild amusement.
>>
>> But the real solution is rail; the infrastructure is mostly in place,
>> its cheaper
>> than road beds, easily electrified and vehicles can be individually
>> controlled
>> and navigated by computer, eliminating the train. You load your
>> vegetables on a truck and send it direct to destination, at night,
>> phasing out 18 wheelers.
> It sounds easy, until you start to understand some of what's involved.
> But dream on, you'll never be the one actually expected to do it.
Rail was always easier than road, that's why it was built first.
It's easier today, we are not limited to grossly underpowered steam
locomotives that can't climb hills so we wouldn't need the tunnels
and bridges the Victorians built. Why, I've even heard of ships that
are nuclear powered, unlike the coal-fired Titanic of your non-existent
old-fashioned imagination.
But you carry on living in the 20th century with your electric motors
that are also generators, but not particularly powerful like this:
http://www.railwayclassics.com/images/acl01/ACL501%20color.jpg
>> Who needs truck drivers anyway? Re-employ them as maintenance crews.
>>
>> If you want to go somewhere you call a rail taxi, board it and the
>> computer takes you to your destination. Or you buy your own computerized
>> rail vehicle.
>> Leave the freeways for those that want to kill themselves with ICEs.
>> Size of market? The whole damn world. Can it be done? Cities had trams,
>> computers are cheap, cell phones... of course it can. Breakdown? push
>> the vehicle off the main rails into a siding
>> and send a repair crew with a tow truck.
> Using the rails? Or do you plan to still have roads for when you really
> need something to work?
No, and I also plan to dump you for the miserable and highly limited
unimaginative old-fashioned fuckhead you really are.
>>> On 6/5/09 7:52 AM, in article
>>> a187370d-0d8a-4565-8cb8-407364942...@d31g2000vbm.googlegroups.com,
>>>
>>>
>>>
>>> >> tgdenn...@earthlink.net wrote:
>>>
>>> >>>> It is very simple. Think of motors in a wheel bouncing down the
>>> >>>> road. Heavy is not good because too much energy is fed right back
>>> >>>> to them because the suspension cannot transfer it quickly enough
>>> >>>> to some putative absorber in the chassis.
>>>
>>> >>>> However, if one distributes the total desired power among four
>>> >>>> wheels, then each will be lighter and life is good again.
>>>
>>> >>>> My friend, I have been building race setups for forty years. I
>>> >>>> know this shit.
>>>
>>> >>> Glad to hear it. I like to talk to people who know what they are
>>> >>> talking about. However, my point does not change---the benefit of 4
>>> >>> electric motors is pretty much the same even if they are 'mounted
>>> >>> inboard'. I am not interested in worrying about what you call them.
>>>
>>> >> Never seen "inboard" mounted wheels on an autombile. What would they
>>> >> look like?
>>>
>>> >http://teslamotorsclub.com/technical/303-hub-motors-dual-motors.html
>>>
>>> That is not an inboard hub motor. It is not a hub motor at all. It is a
>>> perfectly conventional motor. A hub motor is inside the wheel, not
>>> just something that drives the hub. There are no motors or engines that
>>> drive the wheel anywhere but to the hub. None drive at the rim of the
>>> wheel (except for a couple exotic show motorcycles that are
>>> impractical. Citations available.)
>>
>> You lost me there---I'm in favor of using perfectly conventional motors
>> if that works.
>>
>>
>>> If I were home I'd shoot some pics of the Porsche's IRS and you would
>>> see it's connected to the transmission just like that illustration done
>>> by the would-be impressionistic, unlearned contributor to the site in
>>> question.
>>>
>>>
>> The picture is just so people can visualize the possible configuration.
>> I don't see anything wrong with it.
>>
>>
>>> So, let's stick to real-world terms. I would not use the post in
>>> question as a source of any authority.
>>>
>>> > Scroll down to number 8 I think. I would dispense with disc brakes
>>> > on the wheel and put some very simple parking-brake device on the
>>> > inboard side as a 'final ultimate' emergency stopping option, relying
>>> > on electric braking.
>>>
>>> Old hat. We have been mounting disc brakes on drive shafts for many
>>> years. I think Lotus does it. I have done it. You can't turn a disc
>>> brake into a generator. Its lack of a flywheel effect and radius make
>>> it impractical, and also consider that all electric motors are also
>>> generators, but not particularly powerful.
>>
>> Again you've lost me---you are obviously misinterpreting what I said.
>> Braking is done by the electric motor; for most of the braking period
>> you are recovering the kinetic energy, which is why it is called
>> regenerative braking. The ultimate implementation would have no disc
>> brakes at all. If you need further explanation please let me know.
> Motor/generators are transducers, not brakes. That means you can only
> slow down, not come to a complete stop. If the electronic controller
> failed, you couldn't even slow down. How big a market do you expect for
> cars without brakes?
> Remember, everything looks easy to the guy who doesn't actually have to
> do it.