PeteHski

Yeah I was thinking this too. They will for sure have a direct mechanical link from lever to reservoir. So if the electronics should ever fail you still at least have non-assisted hydraulic braking (similar to most modern cars). So don't expect hydraulic hoses to disappear anytime soon, at least not with this patented concept.
You also have 2 independent braking systems on a bike (front and rear brakes) so that gives a safety redundancy too. Good point about cable brakes being totally dependent on the cable not failing. Bike cables never snap right?

ABS functionality actually seems to be the main benefit of this patent. That would be interesting for sure.

Kimmo

Okay, how does this work? Presumably there are rather strong springs to provide all the braking power you might ever need, with the electric actuators holding the brakes open 98% of the time...

Beginning to see the problem with this idea?

ssmiker

I am not advocating fly by wire brakes. But if you use a Maxell 2032 rechargeable battery, a small magnet to induce charge, it might be possible to keep the brakes charged with no maintenance. If you kept the whole thing as one unit it might make a decent touring solution since yo would not need cables, or hoses just an extra brake?

dkatz1

Right. And BIll gates has injected millions of americans with mirco chips.

RGMN

If they just wanted to kill it why would you spend several thousand $ filing a patent and then create something that you would need to track and defend if someone decided to challenge it? Just write a white paper and reveal the details to the world. That way it is in the public domain and no one else can patent it, and all you incur is the cost of the white paper. No future tracking costs, no future liability, no future defense cost.

PeteHski

Occam's razor applies here i.e. the reason why most people patent ideas is pretty obvious. Having to make other assumptions to arrive at an alternative explanation makes it somewhat less likely.

colnago62

The rumor has been debunked as the sun came out in honor of Memorial Day

smashndash

Even with a very heavy ebike, the main bottlenecks for braking will be thermals and grip/going OTB. If you're too weak to pull the brake lever, you're probably too weak to brace your body against the bars to prevent yourself from going OTB. If ebikes end up with boosted brakes, you'll probably see an epidemic of people throwing themselves off the front of their bikes. ABS can mitigate this but probably not solve it entirely.

From what I can tell, even motorcycles with 100+ HP weighing 500+lbs do not have power brakes.

big john

On a tractor-trailer with air brakes only the trailer brakes are locked on when there is no air pressure. If a trailer is disconnected from the tractor air pressure, the brakes can be released by installing screw type devices at the brake actuators to manually force the brakes to release. This has nothing to do with bicycles and was a terrible analogy.
The Shimano system linked in the OP looks to be a booster type thing to allow fine control of the brake power. It's configured in such a way as to allow manual override if the system/battery fails. It does seem to be a totally unnecessary extravagance.

Some electric cars actuate the braking system with a pump which also creates an artificial pedal feel. Again, if there is a failure there is a mechanical ability to push through an apply the brake pressure the old fashioned way.
The advantage to this system is the ability to use regenerative braking. On light braking or gradual stops the brakes are not applied, instead the computer uses regenerative braking (the generator charges the battery) to slow the vehicle. The brakes on the wheels are only applied during hard stops.

So why have this on a bike? Other than fine control and the possibility of an anti-lock feature, it could be the first step toward regenerative braking for e-bikes.

big john

They don't,, but they can have 3 huge brake rotors and massive calipers with giant pads.

smashndash

That's for thermals as far as I know. Does almost nothing to actually make it easier to stop in a normal situation.

But actually I did some research. Looks like motorcycles have around 3x more leverage than bicycles do. Typical hand force to clamp force ratio for a bicycle hydraulic disc brake seems to be around 1:50 whereas typical ratios for motorcycles seems to be around 1:150.

https://bikerumor.com/2020/11/06/aas...brake-answers/

https://www.wristtwisters.com/thread...ylinder.48345/

It seems that motorcycles run their pads with literally 0 clearance to the rotors. They're more than willing to accept some power loss in exchange for higher leverage ratios. Constant brake rub isn't acceptable on pedal bicycles though, so maybe ebikes will have to bridge the gap.

InvertedMP 

I fly the Airbus. The side stick has springs in it to replicate feel.

PeteHski

+1
Knowing the brake lever position/pressure would allow management of regen braking on an e-bike. In an electric car it's a bit different as regen braking is usually managed entirely by throttle position and the mechanical brakes are completely separate, working in parallel with regen braking. So if you lift off the throttle you always get regen braking and if you want to slow down more quickly you press the brake pedal to engage the disc brakes - similar to engine braking in an ICE car. But on an e-bike you don't always want regen braking every time you stop pedalling, since you might well just be coasting, so it needs to know whether or not you are on the brakes.

big john

Some e-cars have the "one pedal" feature where you put the shifter in "low" and every time you lift from the accelerator you get heavy deceleration from regenerative braking. In other words, the computers can vary the load on the generator. When you apply the pedal lightly the deceleration is only from regen and the wheel brakes are not in play. The brake pads on these cars get very little wear.
And I checked, when "one pedal" driving the brake lights do come on when you lift from the gas pedal.

PeteHski

I don't think that is true in practice. We have a couple of Teslas and when you lift completely off the throttle they go into maximum regen braking (smoothly ramped up). But if you only partially lift off the throttle you only get partial regen braking in proportion to how much you lift off. So you can drive the car with "one pedal" simply by feathering the throttle to control how much regen braking you are getting (up to the maximum regen braking available). But as soon as you get on the brake pedal you will already be getting maximum regen braking simply from lifting completely off the throttle and any additional braking force then comes from the disc brakes as the 2 systems work in parallel. There is no scenario where you are applying the brake pedal without activating the brake pads.

The brake lights are simply controlled by the amount of deceleration, not brake pressure. So if you lift off the throttle you will see your brake lights coming on as you have observed.

big john

I don't know Tesla products but I am certified in GM e-cars. I retired in 2019 and braking was not my specialty but the amount of regen varies. The brake pedal is more of a sensing system than a traditional brake pedal which drives the master cylinder, either directly or through a booster.
When you apply the brake pedal the computers decide how much wheel brake to apply, if any, and the pump applies the brakes, if needed, and pushes back against the pedal to create a pedal feel/resistance for the driver. In some driving situations the wheel brakes will not be used, therefore the pads last "forever".
If there is electrical or other system failure the pedal can overcome the pump system and apply the brakes.
In a Volt or a Bolt EV the regen can be pretty strong.

big john

I forgot they also had a paddle on the steering wheel to engage maximum regen which will stop the car without the brakes, according to this guy:

"The Bolt EV comes equipped with a Regen on Demand (RoD) paddle behind the left-side of the steering wheel. To use it, simply pull back against the RoD paddle, and it will apply the maximum amount of regenerative braking force available, without using the friction brakes. When pulled back, the RoD paddle will bring the vehicle to a complete stop in either driving mode (D or L). In Drive, the RoD paddle will provide up to 65 kW of regenerative braking power. In Low, it will provide up to 70 kW. Apparently, you can also hold the RoD paddle down in D while modulating the accelerator to mimic driving in L,"

Bald Paul

The only way I would trust electronic braking on a bicycle would be if it were some type of electronic-assist braking. Sort of like power brakes on your car. Even if the electronics fail, you still have a mechanical connection between the pedal and the piston in the brake master cylinder. Without that fail safe, if the electronics fail, you'd have no brakes.
I had a BMW K1200LT motorcycle (about 800 lbs loaded and fueled up) that was equipped with electronically assisted power brakes. They were incredible. Just for giggles, while riding along where I was the only one on the road, I put the bike in neutral at around 50 MPH, turned the key off (which killed the electronic braking assist) and tried the brakes.
It was at that time that I decided that if I ever saw the warning light for the brake assist come on while I was riding, my ride was over.

Jax Rhapsody

Redundancies that'll add more wieght than a normal ass brake system. I'd rather use twine as a brake cable than ebrakes.

Jax Rhapsody

Any thing with airbrakes uses air to hold the brakes open. The trailer, the truck, even a train will lock the air brakes with no pressure. Nowadays the only reason you'll find runaway trucks and trains is most likely brake fade. Spring brakes allow you to move a truck a short distance before complete lock up from lack of air. Is a poor analogy, though.

PeteHski

As someone else pointed out earlier, what failsafe do you have on a cable rim brake? If the cable fails there is no back-up (except for the other brake of course!). Now I would fully expect this new fangled electronic system to have a mechanical connection (which it very much looks like it does) and again you have 2 brakes anyway, so there is always some redundancy.

Same applies with hydraulic disc brakes. Your only failsafe is in having 2 independent brakes.

PeteHski

Okay, that's a completely different system to what I'm used to. It sounds like GM are using the brake pedal to modulate/blend in regen braking. While Tesla use the throttle pedal to modulate regen braking (hence one-pedal driving) and the brakes are conventional, working in parallel with full regen. So you effectively brake by feathering the throttle and then if you want to brake harder than max regen allows you lift off completely and hit the brake pedal. Whenever you lift completely off the throttle you get full regen braking plus additional braking from the disc brakes when you hit the brake pedal. Again the pads last forever as most of the braking is done with regen. The disc brakes only provide braking force beyond what the regen can handle.

big john

The GM e-cars will do that with the shifter in "low". Except the Spark EV, I don't think they can but I never tried. I know the Spark is a pain the remove the battery, that part I remember.

Bald Paul

I agree, in part. With a cable actuated brake system, or even a hydraulic system, you can inspect the cable/hoses for any wear and repair/replace as needed before they fail completely. I have never seen a cable "just break" or a hydraulic line blow without some type of prior warning/leak.
When an electronic component decides it's time to go, it just goes, and most of the time there is no warning.

On a 800 lb motorcycle travelling at highway speeds, electronically assisted brakes were required. I really don't think there is a need for electronic brake systems on a bicycle. It seems more like a "look what we can do!" rather than "look what needed to be done" type of thing.

Andy Somnifac 

I mean, it's a shame that the only "bikes" you can buy now are eBikes, right? I hate how they forced everyone into buying them and took away our good old human powered ones...