Given a source of 12 VDC and one of 110 VAC at 60 or 400 Hz, how might
synchro operation be established between the driven wheel of a bicycle
or tricycle and the free (nondriven) wheel(s) for all-wheel drive?

IIRC a synchro is a rotary VDT (variable displacement transducer) or
type of transformer. They were used in airplanes (long ago?) to
connect the steering yoke to flight control surfaces (ailerons,
elevator, and rudder)

The reason I ask is I have a Kinetic Energy Recovery Bicycle group on
LinkedIn. Any of you here would be welcome there. Our goal is to save
lives and smooth bicycle/automotive traffic interaction with
regenerative braking of bicycles/tricycles as they approach a stop,
including "winding up some joules" while stopped (applicable to
trikes) by backpedaling. With energy on board, extending the
development to all-wheel drive seems a natural next step--for a
different purpose and market, though.

We've discussed magnets in the rim and an arc of electromagnets along
an arc near the rim, as one method of drive, and then I though, that
looks like it could be a synchro. Without a synchro, we'd have to
measure the torque at the pedal driven wheel, and control power input
to the electric wheel(s)...way too much trouble, like building an ABS
from the ground up. We can assume our trike has 3 same-size wheels.

There's no reason to reinvent...the wheel. (giggle)

Douglas (Dana) Goncz
Replikon Research
Seven Corners, VA 22044-0394

On Dec 31, 3:16*am, The Dougster
wrote:
Given a source of 12 VDC and one of 110 VAC at 60 or 400 Hz, how might
synchro operation be established between the driven wheel of a bicycle
or tricycle and the free (nondriven) wheel(s) for all-wheel drive?

IIRC a synchro is a rotary VDT (variable displacement transducer) or
type of transformer. They were used in airplanes (long ago?) to
connect the steering yoke to flight control surfaces (ailerons,
elevator, and rudder)

The reason I ask is I have a Kinetic Energy Recovery Bicycle group on
LinkedIn. Any of you here would be welcome there. Our goal is to save
lives and smooth bicycle/automotive traffic interaction with
regenerative braking of bicycles/tricycles as they approach a stop,
including "winding up some joules" while stopped (applicable to
trikes) by backpedaling. With energy on board, extending the
development to all-wheel drive seems a natural next step--for a
different purpose and market, though.

We've discussed magnets in the rim and an arc of electromagnets along
an arc near the rim, as one method of drive, and then I though, that
looks like it could be a synchro. Without a synchro, we'd have to
measure the torque at the pedal driven wheel, and control power input
to the electric wheel(s)...way too much trouble, like building an ABS
from the ground up. We can assume our trike has 3 same-size wheels.

There's no reason to reinvent...the wheel. (giggle)

Douglas (Dana)Goncz
Replikon Research
Seven Corners, VA 22044-0394

I looked up synchros and found they usually relay position. They don't
usually control a load unless an amplidyne is used.

From the Wikipedia:

"How an amplidyne works

An amplidyne is a special type of motor-generator which uses
regeneration to increase its gain. Energy comes from the motor, and
the power output is controlled by changing the field current of the
generator. In a typical generator the load brushes are positioned
perpendicular to the magnetic field flux. To convert a generator to an
amplidyne you connect what would be the load brushes together and take
the output from another set of brushes that are parallel with the
field. The perpendicular brushes are now called the 'quadrature'
brushes. This simple change can increase the gain by a factor of
10,000 or more."

More recently, power FETs are used.


Doug

You don't need to sense pedal torque, the driven wheel either has
enough traction or it slips. When it slips you have a speed difference
between the wheels that you can sense and correct. You don't need to
accurately measure the difference, just null it out.

The All Wheel Drive on my car detects a difference between front and
rear axle speed and connects power to the rear axle proportionally to
the difference. Each axle drives a pump that moves hydraulic fluid in
a circle. A speed difference lets pressure build up and operate a
clutch cylinder. There's some allowance for cornering and driving in
reverse but it's a simple concept that works very well.

For an electronic version you could sense wheel speeds as DC voltages,
subtract the main and slave voltages and power the slave wheels
proportionally to the difference, with a small dead band. You'd need
PM motors etc for tachs to sense speed, a low-gain op amp to compare
them, and an H bridge or PWM controller for the slave wheel motors.
And a kill or dead-man switch.

I love the irony of printing KILL KILL KILL KILL on the label maker
when I'm assembling *safety* equipment.

My truck has an all-mechanical 4WD with no center differential, both
axles turn at the same speed. In very slippery conditions both work
well, any difference is masked by the different weight distributions.
In marginal conditions the AWD slips a bit before the rear axle
engages but I don't feel it, only hear the tire noise. There is no
feedback to the steering wheel. At speed I think stable steering is
more important than maximum traction, having owned a Civic that
oversteered on ice.

Ever ride a dirt bike on a slippery surface? If the rear drive wheel
can slip you don't have much steering traction either. When you brake
enough that the front wheel slips you go DOWN.

A three-wheeler with an electric motor driving a rear differential
might be easy to do and work well. Separate wheel motor drives would
give you dangerous steering problems at more than lawn tractor speed.
Once you go fast enough for wheel hop things can become complicated.

ABS is really simple until you add on all the fail-safe circuits. I
built the test stations for the first analog electronic ones in the
70's.

jsw

On 2009-12-31, The Dougster wrote:
Given a source of 12 VDC and one of 110 VAC at 60 or 400 Hz, how might
synchro operation be established between the driven wheel of a bicycle
or tricycle and the free (nondriven) wheel(s) for all-wheel drive?

IIRC a synchro is a rotary VDT (variable displacement transducer) or
type of transformer. They were used in airplanes (long ago?) to
connect the steering yoke to flight control surfaces (ailerons,
elevator, and rudder)

Actually -- the synchros which I have seen/used don't have
enough torque to do what you want, nor do they have enough to control
the flight surfaces.

They were good at feedback from the remote control surface to
tell the controller what position it has reached, so the servo motor (a
different thing) could be told to keep trying until it got there. Best
is to power one end's rotor with the AC, and compare that voltage to the
voltage induced in the rotor at the other end. The difference will be
zero when the two are pointing the same direction. Amplify the
difference and use it to power the AC servo motor to position things.
Still not what you really want on what you are building.

Smaller ones were used to drive pointers in navigation
instruments.

I guess that a synchro *could* generate the torque you
need/want, but the total size and weight would make it a losing
proposition. I picture one perhaps four or five feet in diameter, and
maybe 8 feet long to do it with 60 Hz. A bit smaller at 400 Hz, but you
still have to generate that much power.

The reason I ask is I have a Kinetic Energy Recovery Bicycle group on
LinkedIn. Any of you here would be welcome there. Our goal is to save
lives and smooth bicycle/automotive traffic interaction with
regenerative braking of bicycles/tricycles as they approach a stop,
including "winding up some joules" while stopped (applicable to
trikes) by backpedaling. With energy on board, extending the
development to all-wheel drive seems a natural next step--for a
different purpose and market, though.

We've discussed magnets in the rim and an arc of electromagnets along
an arc near the rim, as one method of drive, and then I though, that
looks like it could be a synchro. Without a synchro, we'd have to
measure the torque at the pedal driven wheel, and control power input
to the electric wheel(s)...way too much trouble, like building an ABS
from the ground up. We can assume our trike has 3 same-size wheels.

An interesting approach -- but I doubt that you could get enough
power through it. They really are not designed for power -- just for
driving things like a compass card, driving it from a gyrocompass (the
60 Hz ones used by the Navy once upon a time.)

There's no reason to reinvent...the wheel. (giggle)

I think that perhaps you do need to do just that. The drive
from coils next to the rim might work for other types of motors, but not
for synchros.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

DoN. Nichols wrote:

Actually -- the synchros which I have seen/used don't have
enough torque to do what you want, nor do they have enough to control
the flight surfaces.

They were good at feedback from the remote control surface to
tell the controller what position it has reached, so the servo motor (a
different thing) could be told to keep trying until it got there. Best
is to power one end's rotor with the AC, and compare that voltage to the
voltage induced in the rotor at the other end. The difference will be
zero when the two are pointing the same direction. Amplify the
difference and use it to power the AC servo motor to position things.
Still not what you really want on what you are building.


Don, there were basically three types of "Synchros".
Generators, Motors, and Control Transformers.(CT)
The ones that used an amplifier and servo drive motor
were the CTs. That is what was used in PPI scopes
to control the rotating yoke. (I forget the size
designations) The Generators and Motors would
produce a fair amount of actual positional force.
The Generators were not as suitable for an output
end as they were not damped, but the general config.
was the same as the motor. (I had a pair of those
from the surplus when our outfit was broken up in
1952 and may still be in the "milk house" in PA)
The CTs were constructed with a completely different
rotor and could not be powered like the motors.
Finally something I have had experience with. :-)
...lew...

"DoN. Nichols" wrote in message
...
On 2009-12-31, The Dougster wrote:
Given a source of 12 VDC and one of 110 VAC at 60 or 400 Hz, how might
synchro operation be established between the driven wheel of a bicycle
or tricycle and the free (nondriven) wheel(s) for all-wheel drive?


FWIW, I have a pair of 60 hz synchros here - if I tie the x,y,z leads
together and also parallel the excitation leads, one syncrho will follow the
other nicely - and the torque is enough foot pounds that it's well nigh
impossible to hold - these units are about 8 inches long and 4 to 5 inches
in diameter.

This would most assuredly be one of the last ways I would attempt to achieve
all wheel drive -it is horribly inefficient, very expensive for the large
syncrhos and very heavy - a much more standard solution would be to just use
three separate DC or AC motors

Syncro's are sense and transmit the same rotation.

I have several sets - some very large.

I'd think they could be on a steering wheel and then hydrologists
then slave power from another source to the small control power making
the distant and resistant to move actually do it.

e.g. flight control surface. Drive or sense where it is and feed it back.

Torque on one won't consider driving a wheel if someone is sitting.

Martin



The Dougster wrote:
Given a source of 12 VDC and one of 110 VAC at 60 or 400 Hz, how might
synchro operation be established between the driven wheel of a bicycle
or tricycle and the free (nondriven) wheel(s) for all-wheel drive?

IIRC a synchro is a rotary VDT (variable displacement transducer) or
type of transformer. They were used in airplanes (long ago?) to
connect the steering yoke to flight control surfaces (ailerons,
elevator, and rudder)

The reason I ask is I have a Kinetic Energy Recovery Bicycle group on
LinkedIn. Any of you here would be welcome there. Our goal is to save
lives and smooth bicycle/automotive traffic interaction with
regenerative braking of bicycles/tricycles as they approach a stop,
including "winding up some joules" while stopped (applicable to
trikes) by backpedaling. With energy on board, extending the
development to all-wheel drive seems a natural next step--for a
different purpose and market, though.

We've discussed magnets in the rim and an arc of electromagnets along
an arc near the rim, as one method of drive, and then I though, that
looks like it could be a synchro. Without a synchro, we'd have to
measure the torque at the pedal driven wheel, and control power input
to the electric wheel(s)...way too much trouble, like building an ABS
from the ground up. We can assume our trike has 3 same-size wheels.

There's no reason to reinvent...the wheel. (giggle)

Douglas (Dana) Goncz
Replikon Research
Seven Corners, VA 22044-0394

It sounds like they want to steal power through the synchros and drive
another wheel. Using lots of power for the core that transfers to the
other.

It is an idea, not a good one for a project like this.

Martin

Bill Noble wrote:


"DoN. Nichols" wrote in message
...
On 2009-12-31, The Dougster wrote:
Given a source of 12 VDC and one of 110 VAC at 60 or 400 Hz, how might
synchro operation be established between the driven wheel of a bicycle
or tricycle and the free (nondriven) wheel(s) for all-wheel drive?


FWIW, I have a pair of 60 hz synchros here - if I tie the x,y,z leads
together and also parallel the excitation leads, one syncrho will follow
the other nicely - and the torque is enough foot pounds that it's well
nigh impossible to hold - these units are about 8 inches long and 4 to 5
inches in diameter.

This would most assuredly be one of the last ways I would attempt to
achieve all wheel drive -it is horribly inefficient, very expensive for
the large syncrhos and very heavy - a much more standard solution would
be to just use three separate DC or AC motors

Lewis Hartswick wrote:
DoN. Nichols wrote:

Actually -- the synchros which I have seen/used don't have
enough torque to do what you want, nor do they have enough to control
the flight surfaces.

They were good at feedback from the remote control surface to
tell the controller what position it has reached, so the servo motor (a
different thing) could be told to keep trying until it got there. Best
is to power one end's rotor with the AC, and compare that voltage to the
voltage induced in the rotor at the other end. The difference will be
zero when the two are pointing the same direction. Amplify the
difference and use it to power the AC servo motor to position things.
Still not what you really want on what you are building.


Don, there were basically three types of "Synchros".
Generators, Motors, and Control Transformers.(CT)
The ones that used an amplifier and servo drive motor
were the CTs. That is what was used in PPI scopes
to control the rotating yoke. (I forget the size
designations) The Generators and Motors would
produce a fair amount of actual positional force.
The Generators were not as suitable for an output
end as they were not damped, but the general config.
was the same as the motor. (I had a pair of those
from the surplus when our outfit was broken up in
1952 and may still be in the "milk house" in PA)
The CTs were constructed with a completely different
rotor and could not be powered like the motors.
Finally something I have had experience with. :-)
...lew...

But they wre never intended to move control surfaces.
Just instrument indicators.

Controls take *torque*...

"The Dougster" wrote in message
...

The reason I ask is I have a Kinetic Energy Recovery Bicycle group on
LinkedIn. Any of you here would be welcome there. Our goal is to save
lives and smooth bicycle/automotive traffic interaction with
regenerative braking of bicycles/tricycles as they approach a stop,
including "winding up some joules" while stopped (applicable to
trikes) by backpedaling. With energy on board, extending the
development to all-wheel drive seems a natural next step--for a
different purpose and market, though.


I am old enough to remember when the Schwinn Varsity was panned by all the
bike aficionados because it was a few pounds heaver than the whizz bang
French, Italian or Japanese bicycle.

Now you are suggesting to add weight so that after you pedal up the long
grade you can recover some of the energy when you are going down hill to
make it easier to go up the next hill.

Unless I am missing something, seems to me you will be expending more energy
to go the same distance on your ride.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.

On Sat, 2 Jan 2010 09:11:52 -0800, the renowned "Roger Shoaf"
wrote:


"The Dougster" wrote in message
...

The reason I ask is I have a Kinetic Energy Recovery Bicycle group on
LinkedIn. Any of you here would be welcome there. Our goal is to save
lives and smooth bicycle/automotive traffic interaction with
regenerative braking of bicycles/tricycles as they approach a stop,
including "winding up some joules" while stopped (applicable to
trikes) by backpedaling. With energy on board, extending the
development to all-wheel drive seems a natural next step--for a
different purpose and market, though.


I am old enough to remember when the Schwinn Varsity was panned by all the
bike aficionados because it was a few pounds heaver than the whizz bang
French, Italian or Japanese bicycle.

Now you are suggesting to add weight so that after you pedal up the long
grade you can recover some of the energy when you are going down hill to
make it easier to go up the next hill.

Unless I am missing something, seems to me you will be expending more energy
to go the same distance on your ride.

I think the improvement would come if you could capture, store and
return some of the energy that is dissipated as heat when the cyclist
uses the brakes. Being able to recover the energy might encourage
cyclists to not just sail through stop signs and to maintain more
reasonable speeds on down grades. For example, imagine a flywheel that
would spin up when you are stopping for an intersection or going down
a long grade. Then you could use that energy to boost yourself back up
to speed. Sort of a hybrid.. and the weight added would be much less
than if you tried to power the bike continuously.

If you seldom touch the brakes, it's not going to save anything
significant.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

"Spehro Pefhany" wrote in message
...

I think the improvement would come if you could capture, store and
return some of the energy that is dissipated as heat when the cyclist
uses the brakes. Being able to recover the energy might encourage
cyclists to not just sail through stop signs and to maintain more
reasonable speeds on down grades. For example, imagine a flywheel that
would spin up when you are stopping for an intersection or going down
a long grade. Then you could use that energy to boost yourself back up
to speed. Sort of a hybrid.. and the weight added would be much less
than if you tried to power the bike continuously.

If you seldom touch the brakes, it's not going to save anything
significant.


Best regards,
Spehro Pefhany

I understand what he is trying to accomplish, but it seems to me that there
are several problems that might be very difficult to overcome. First off
lets say you were able to store energy in a flywheel. First you will have
extra energy expended to pedal the flywheel up the hill, then you are at the
bottom of the hill stopped and have a big old gyroscope that will create
mischief if you need to change direction. I seem to recall that this
flywheel idea was tried in automobiles and abandoned for that reason.

Next, if you were to try to convert the wheels of the bicycle into a
generator, then attempt to store the electricity into batteries, you have
some practical problems as well. First off you increase the weight
requiring more energy to be expended going up the hill. Next your generator
will be operating at a whole lot of different speeds and that is going to be
a real pain to efficiently regulate the voltage to charge the batteries.

Think of how much weight and space it would require to have enough battery
power available to go up hill at any decent rate of speed. Now think about
having to pedal that weight up a hill or even drag it around on the
flatland. Seems to me you are going to pay too big a price to get little in
return.

Just my 2 cents.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.