Stromer ABS ??

[MinnBobber]

Their ABS is said to have “roll-over protection when brakes fully applied”.
Does this mean it can prevent the deadly front flip in an emergency braking situation?

That is more important to me vs anti skidding of front tire.
Anyone know??
Thanks

 

[bluecat]

Their ABS is said to have “roll-over protection when brakes fully applied”.
Does this mean it can prevent the deadly front flip in an emergency braking situation?

Have a closer look on the two video. The blubrake video shows the intention of the ABS. I've added some slow motions which unveil: No hard braking was made. But the concept is visible. My own video shows, how it works when hard (or panic) braking occurs: Front wheel locks for a fraction of a second, then the ABS performs a smooth braking.

 

[fooferdoggie]

since Bosch was the first one with it. but so far it does not seem to have gone anywhere.

 

[Johnny]

Their ABS is said to have “roll-over protection when brakes fully applied”.
Does this mean it can prevent the deadly front flip in an emergency braking situation?

That is more important to me vs anti skidding of front tire.
Anyone know??
Thanks

On paper it should be able to prevent it. Cruising >20mph I would really welcome this since in an emergency rolling over the bike is quite easy and very dangerous. After all not everyone has the skills/reaction time to move their weight and modulate the brakes in the event of an emergency braking.


btw ABS for motorcycles has been around for almost 30 years and the so called ebike version is just a straightforward adaptation of it not boschs or any other ebike companys invention.

 

[fooferdoggie]

On paper it should be able to prevent it. Cruising >20mph I would really welcome this since in an emergency rolling over the bike is quite easy and very dangerous. After all not everyone has the skills/reaction time to move their weight and modulate the brakes in the event of an emergency braking.


btw ABS for motorcycles has been around for almost 30 years and the so called ebike version is just a straightforward adaptation of it not boschs or any other ebike companys invention.

but bike brakes don't usually have electronics involved they are pretty simple. I have had panic stops and not lost control. I cant steer much as my brain does not allow that.

 

[MinnBobber]

On paper it should be able to prevent it. Cruising >20mph I would really welcome this since in an emergency rolling over the bike is quite easy and very dangerous. After all not everyone has the skills/reaction time to move their weight and modulate the brakes in the event of an emergency braking.


btw ABS for motorcycles has been around for almost 30 years and the so called ebike version is just a straightforward adaptation of it not boschs or any other ebike companys invention.

My concern is that an ABS system COULD make emergency braking front flips more likely AS it gives one maximum braking force……does that equal more flip forces?

A skidding tire (no ABS) has less traction so less front flip forces??? but skidding tire certainly can foster other loss of control scenarios.

Does bike ABS really help prevent front flips ?
Since it is set for max traction, does that promote front flips?
Kind of theoretical here but also what is the reality?

Part of me can’t help but think ABS without some sort of electronics, like motorcycle anti wheelie program, that max ABS braking power = front flips more likely.
Does it modulate any way to prevent flips?

Help me understand the dynamics better , thanks

 

[Johnny]

My concern is that an ABS system COULD make emergency braking front flips more likely AS it gives one maximum braking force……does that equal more flip forces?

A skidding tire (no ABS) has less traction so less front flip forces??? but skidding tire certainly can foster other loss of control scenarios.

Does bike ABS really help prevent front flips ?
Since it is set for max traction, does that promote front flips?
Kind of theoretical here but also what is the reality?

Part of me can’t help but think ABS without some sort of electronics, like motorcycle anti wheelie program, that max ABS braking power = front flips more likely.
Does it modulate any way to prevent flips?

Help me understand the dynamics better , thanks

You can find detailed information by searching how abs work in motorcycles.

But to put it simply, there is relative rotational motion between the front wheel and your frame. You front wheel is rotating with respect to the frame of the bicycle, this is the same relative motion as your whole frame rotating along the axis of the front wheel when the wheel is not turning.

In an emergency braking situation The braking force creates a moment in the opposing direction of the rotation of your wheel. if your wheel gets locked(your wheel stops rotating), you will go into the state where this moment will rotate whole frame towards the front, around front wheel's axis.
ABS prevents your wheel from getting locked, that is, your wheel will keep on turning so you will never go into the aforementioned state and you will not roll over the bicycle.

 

[bluecat]

In an emergency braking situation The braking force creates a moment in the opposing direction of the rotation of your wheel. if your wheel gets locked(your wheel stops rotating), you will go into the state where this moment will rotate whole frame towards the front, around front wheel's axis.
ABS prevents your wheel from getting locked, that is, your wheel will keep on turning so you will never go into the aforementioned state and you will not roll over the bicycle.

Thanks for your observations regarding road motorcycles. This gives me the opportunity to explain the difference to the ST5 ABS commuter bicycle.

A motorcycle has often three times the weight of its rider - and the center of gravity is clearly below the handlebar. In case of the Stromer, it's the complete opposite: The rider has mostly three times the weight of the ST5 ABS and the center of gravity is far above the handlebar. The leverage force to throw the rider over the handlebar is much bigger - and takes in place before the front wheel is blocked.

Therefore, the main job of the ABS on the ST5 is provide a smooth negative acceleration. To control this, a gyroscope sensor is part of the bluebrake system. This is, what the video above shall illustrate.

 

[MinnBobber]

Thank

Thanks for your observations regarding road motorcycles. This gives me the opportunity to explain the difference to the ST5 ABS commuter bicycle.

A motorcycle has often three times the weight of its rider - and the center of gravity is clearly below the handlebar. In case of the Stromer, it's the complete opposite: The rider has mostly three times the weight of the ST5 ABS and the center of gravity is far above the handlebar. The leverage force to throw the rider over the handlebar is much bigger - and takes in place before the front wheel is blocked.

Therefore, the main job of the ABS on the ST5 is provide a smooth negative acceleration. To control this, a gyroscope sensor is part of the bluebrake system. This is, what the video above shall illustrate.

Thank you for this clarification @bluecat !!!
I was hoping for a gyro system as straight ABS would seem to increase the probability of a front flip as it provides maximum braking force, with the high center of gravity on a Stromer, this max deceleration would equal front flip.

If the front wheel locks /skids then traction is lost and braking force is LESS so no front flip, just other control issues. A locked front wheel/tire equals a big skid but not a front flip.

I would then characterize the Stromer ABS as the reverse of motorcycle “anti-wheelie systems”. They keep motorcycle from flipping over backwards under too much acceleration while Stromer ABS keeps bike from front flipping under too great of deceleration.

IMO, preventing front flips is much more important than a traditional ABS, non-skid system, which maximizes brake force and can foster front flips.

This now makes me excited to get a Stromer with their “AFS” ABS , anti-flip system!!!!
Thanks again bluecat for this info

 

[Johnny]

Therefore, the main job of the ABS on the ST5 is provide a smooth negative acceleration. To control this, a gyroscope sensor is part of the bluebrake system.

I believe some of the motorcycle abs systems also make use of gyroscopes. And what you point out is the job of an abs whether it is a bicycle or a motorcycle am I mistaken ?

I agree that because cg is higher with ebikes they are easier to flip over.

 

[MinnBobber]

I believe some of the motorcycle abs systems also make use of gyroscopes. And what you point out is the job of an abs whether it is a bicycle or a motorcycle am I mistaken ?

I agree that because cg is higher with ebikes they are easier to flip over.

Motorcycle ABS systems can make use of gyroscopes and accelerometers. They can be computer coordinated with the bike systems to provide anti-wheelie protection and anti-stoppie protection.
If a wheelie is imminent they can reduce engine power to lower the acceleration forces.
If they detect a stoppie is happening, they relax the front brake level to reduce the deceleration forces.
This is independent of anti-lock protection, a stoppie can happen well short of the front wheel locking up/ front tire losing grip and skidding.

That’s why it’s so good to hear that Stromer abs goes beyond anti-lock brake protection, takes it to the next level of anti-stoppie protection.

 

[Johnny]

Motorcycle ABS systems can make use of gyroscopes and accelerometers. They can be computer coordinated with the bike systems to provide anti-wheelie protection and anti-stoppie protection.
If a wheelie is imminent they can reduce engine power to lower the acceleration forces.
If they detect a stoppie is happening, they relax the front brake level to reduce the deceleration forces.
This is independent of anti-lock protection, a stoppie can happen well short of the front wheel locking up/ front tire losing grip and skidding.

That’s why it’s so good to hear that Stromer abs goes beyond anti-lock brake protection, takes it to the next level of anti-stoppie protection.

It was erroneous on my part to only mention the state where the wheel locks. It doesn't need to completely lock, the leftover kinetic energy that can not be absorbed by friction etc. will translate into rotational motion. The whole bike will simply rotate with the front wheel.

While abs name only states anti-lock, my understanding was that it was actually used for general control systems which uses feedback from sensors such as gyroscope to keep the vehicle at a controllable state. For bikes this state is both wheels staying on the ground and moving in the direction that the front wheel is facing. For braking this is achieved by loosening front brakes just enough to keep this stable state.