Heavy Hub Motors: Unsprung weight issue solved: Hub motor = in wheel active suspension system!?

I'm surprised nobody has brought up curb damage, ppl wanting custom rims, snow, salt, specialty machines to change tires. Do you know how often wheel speed sensors go bad for brakes, imagine hall sensors subjected to the same environments, not to mention the bazillion pounds of metal shavings on the roads at any given moment from the lack of maintenance on 90% of the vehicles on the road. Plus if you are unlucky enough to live in places like Baltimore or DC or NYC you would need new wheels/motors every other month. I think manufacturers understand the baha like roads that our cities are made of thus they shy away from hub motors.
 
Elias lector said:
I'm surprised nobody has brought up curb damage, ppl wanting custom rims, snow, salt, specialty machines to change tires. Do you know how often wheel speed sensors go bad for brakes, imagine hall sensors subjected to the same environments, not to mention the bazillion pounds of metal shavings on the roads at any given moment from the lack of maintenance on 90% of the vehicles on the road. Plus if you are unlucky enough to live in places like Baltimore or DC or NYC you would need new wheels/motors every other month. I think manufacturers understand the baha like roads that our cities are made of thus they shy away from hub motors.
Click to expand...
Yes; the roads are bad. And if you think they're bad there, you should see them here! (The 'New' South Africa and Africa in general)

Now did you watch the video of the Bose Active Suspension sensing and jumping over bricks, potholes etc?
Did you see it retracting the wheel/s just the right amount and extending it again for it to go over the pothole with zero movement of the car body?

Now IF that active suspension is in the wheel, between the hub and the rim; then the hub motor with all its hall sensors and whatever is as still as the cart body in the video.

If you look at the 1st video; the hub Motor does DOUBLE DUTY as both a motor AND a fully active suspension...
ie: You can take the heavy suspension and shock in your bike, car, truck and throw it away! Because you no longer need it! Its just dead weight..!

Also; if the hub of every wheel is now (better than) sprung weight,
then
you deduct the weight of the hub, brake disk, suspension arms from your unsprung weight and move it all over to sprung weight, where it doesn't need to be designed as heavy and large.
So what does that leave you in unsprung weight?
The outer rim and the tire.
How much does that weigh vs the unsprung weight of the status quo?
And what does reducing unsprung weight by 60-70% do for vehicle dynamics..??

So now its not just the increased reliability of of the hub motors now being (better than) sprung.
That nullifies the weight=power constrains that apply to unsprung hub motors..!
Its a decrease sprung weight. (now better than sprung) and in a car; an increase in space and better aerodynamics.
And a decrease in unsprung weight buy a LOT! Including the now big/powerful hub motor.
Which will do wonders for vehicle dynamics and road-holding..?
 
Last edited:
Logic11 said:
Yes; the roads are bad. And if you think they're bad there, you should see them here! (The 'New' South Africa and Africa in general)

Now did you watch the video of the Bose Active Suspension sensing and jumping over bricks, potholes etc?
Did you see it retracting the wheel/s just the right amount and extending it again for it to go over the pothole with zero movement of the car body?

Now IF that active suspension is in the wheel, between the hub and the rim; then the hub motor with all its hall sensors and whatever is as still as the cart body in the video.

If you look at the 1st video; the hub Motor does DOUBLE DUTY as both a motor AND a fully active suspension...
ie: You can take the heavy suspension and shock in your bike, car, truck and throw it away! Because you no longer need it! Its just dead weight..!

Also; if the hub of every wheel is now (better than) sprung weight,
then
you deduct the weight of the hub, brake disk, suspension arms from your unsprung weight and move it all over to sprung weight, where it doesn't need to be designed as heavy and large.
So what does that leave you in unsprung weight?
The outer rim and the tire.
How much does that weigh vs the unsprung weight of the status quo?
And what does reducing unsprung weight by 60-70% do for vehicle dynamics..??

So now its not just the increased reliability of of the hub motors now being (better than) sprung.
That nullifies the weight=power constrains that apply to unsprung hub motors..!
Its a decrease sprung weight. (now better than sprung) and in a car; an increase in space and better aerodynamics.
And a decrease in unsprung weight buy a LOT! Including the now big/powerful hub motor.
Which will do wonders for vehicle dynamics and road-holding..?
Click to expand...
Did you see any power consumption figures for that? Unless they're doing something so high tec it's near magical that figure is going to be a high one, energy can be recovered from suspension movement but not without losses and on poorly maintained roads it could be running at hundreds of sense-responses a second. If/when it finds it's way onto EVs it'll likely need "eco mode" settings to avoid complaints of crappy range from owners regularly traveling on poor roads.
 
Elias lector said:
I'm surprised nobody has brought up curb damage, ppl wanting custom rims, snow, salt, specialty machines to change tires. Do you know how often wheel speed sensors go bad for brakes, imagine hall sensors subjected to the same environments, not to mention the bazillion pounds of metal shavings on the roads at any given moment from the lack of maintenance on 90% of the vehicles on the road. Plus if you are unlucky enough to live in places like Baltimore or DC or NYC you would need new wheels/motors every other month. I think manufacturers understand the baha like roads that our cities are made of thus they shy away from hub motors.
Click to expand...

I mean yeah.. this is a significant problem even on bikes with 26"-29" wheels.. so bikes have an advantage in that the hub motor is usually much higher up.. and we still suffer of these problems.
 
Logic11 said:
Now did you watch the video of the Bose Active Suspension sensing and jumping over bricks, potholes etc?
Did you see it retracting the wheel/s just the right amount and extending it again for it to go over the pothole with zero movement of the car body?
Click to expand...

Screenshot_20240907-110515~3.png
From Snow Crash by Neal Stephenson, 1992
 
stan.distortion said:
Did you see any power consumption figures for that? Unless they're doing something so high tec it's near magical that figure is going to be a high one, energy can be recovered from suspension movement but not without losses and on poorly maintained roads it could be running at hundreds of sense-responses a second. If/when it finds it's way onto EVs it'll likely need "eco mode" settings to avoid complaints of crappy range from owners regularly traveling on poor roads.
Click to expand...
A very good point stan.
And one that's been bothering me for a day or 2 now having thought this through some more.

The forces to the spokes look like they would cancel each other out should the hub try to fall to the rim floor..? So no losses there I dont think.
How much juice the the electronics would need I have no idea.

But hope springs eternal! :)
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The biggest problem with swingarm mounted motors is the torque reaction of the motor on the suspension. My first build had a qs205/50 in a 19” wheel that weighed 43lbs. With the asi controller I achieved 93mph. But at that speed I was limited because of the pogo sticking effect. With the torque reaction on the suspension it would cause the rear end to lift when it had traction, and sag when it lost it. This turned into an oscillating motion that would have me pogo sticking and unable to find traction at speed, and skipping forward when it would bounce up. A solution to this would be floating torque arms with a reaction link mounted to the frame like racing motorcycles have for the rear disc caliper. Or just go mid drive and solve the other problems like high unsprung weight which along with the torque reaction problem, causes the “hub motor stutter” at medium to high lean angles where it skips out in a stutter before really sliding out and causing you to highside.
 
Tony01 said:
The biggest problem with swingarm mounted motors is the torque reaction of the motor on the suspension. My first build had a qs205/50 in a 19” wheel that weighed 43lbs. With the asi controller I achieved 93mph. But at that speed I was limited because of the pogo sticking effect. With the torque reaction on the suspension it would cause the rear end to lift when it had traction, and sag when it lost it. This turned into an oscillating motion that would have me pogo sticking and unable to find traction at speed, and skipping forward when it would bounce up. A solution to this would be floating torque arms with a reaction link mounted to the frame like racing motorcycles have for the rear disc caliper. Or just go mid drive and solve the other problems like high unsprung weight which along with the torque reaction problem, causes the “hub motor stutter” at medium to high lean angles where it skips out in a stutter before really sliding out and causing you to highside.
Click to expand...
Ummm... not swing arm:
The 3 wheel 'spokes' are actuated by 3 separate electric motors.
The motors turn forward, mostly together, to drive the vehicle, but their speed varies to actuate the active 'In Spoke' suspension.

3 Motors is more inefficient than 1 big one (copper losses if I've got it right) and then how much juice for the 'look ahead' computer control and for keeping the vehicle suspended..??

So a clever idea is all it is at this point.
(But the ride and ability to jump pot holes and spike strips makes active suspension like the Bose System very interesting)
 
As somebody else pointed out, the amount of current that you'd need to move the counter-rotating motors to deflect the wheel up or down in a few milliseconds would be massive. This is a primary problem. The way you could combat that, of course, is to make everything really light, but then you don't even need the whole suspension system because now your unsprung mass is not so big anymore. It's a difficult problem. I do like the idea, however.
 
Cars are already way too complex, heavy, and energy wasting. Why make that worse?

Car wheels are a bad enough place for brakes... why would you put a motor in there as well?

Active suspension draws massive amounts of power ( both raw voltage and CPU processing power )

Inboard brake/motor units make a lot more sense, no more difficult than the CV axles most cars have now. Cooling wouldn't be the issue it used to be ( inboard disk brakes go back over 50 years) since regen braking could take much of the load off the friction brakes

Suspension wheels have been around for over a century, they never seem to work as well as their inventor claims they will.
 
Logic11 said:
Ummm... not swing arm:
The 3 wheel 'spokes' are actuated by 3 separate electric motors.
The motors turn forward, mostly together, to drive the vehicle, but their speed varies to actuate the active 'In Spoke' suspension.

3 Motors is more inefficient than 1 big one (copper losses if I've got it right) and then how much juice for the 'look ahead' computer control and for keeping the vehicle suspended..??

So a clever idea is all it is at this point.
(But the ride and ability to jump pot holes and spike strips makes active suspension like the Bose System very interesting)
Click to expand...
The best suspension works when sprung components are as light as possible, and a wheel is strongest when it has a hub. So point one; it will probably not be very much lighter than a typical wheel if all the strength must come from the rim.

It would have to be some very rigid mechanical assemblies in that complex wheel to handle the loads on the axle as well. Point 2, it would absolutely be heavier than any modern suspension.

3 motors can be in anything. Not a point to show off with the inherent reduced reliability that’s a requirement for operation.
 
Tony01 said:
The best suspension works when sprung components are as light as possible, and a wheel is strongest when it has a hub. So point one; it will probably not be very much lighter than a typical wheel if all the strength must come from the rim.

It would have to be some very rigid mechanical assemblies in that complex wheel to handle the loads on the axle as well. Point 2, it would absolutely be heavier than any modern suspension.

3 motors can be in anything. Not a point to show off with the inherent reduced reliability that’s a requirement for operation.
Click to expand...
yep; the more I think about it the more I think it's a clever concept on paper...

Very good point about the rim having to be heavy to to strong enough.
However any weight besides that is sprung in the same way the chassis of the car is sprung...

But one cannot afford to expend the energy required to keep the hub 'up in the center'.
ie; Hold the car up against gravity which is what the wheel was invented for in the 1st place.
 
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