Cornering ABS

[Motofool]

Copied from
http://www.roadrunner.travel/2016/03...cornering-abs/

"The next big breakthrough is cornering ABS. When a motorcycle is braking in a straight line with no lateral forces acting on it, virtually 100 percent of the tire’s grip is available for braking. As a motorcycle leans over, cornering forces require a larger percentage of the traction available between the tires’ tread and the road surface. Therefore, the portion of the tires’ grip that is available for braking is reduced as the lean angle increases. At maximum lean angle, there’s essentially no more grip available for braking, as added forces will cause the tire to slide out.

Cornering ABS has a complex and difficult job. It must determine not only wheel speeds, but also cornering forces and lean angles, and constantly and rapidly calculate what proportion of full braking force, called for by the rider, may be applied to the individual brakes. This requires accurate and fast-acting sensors, computing power, and actuators, along with complex software.

Presently two German companies, Bosch and Continental, are the pioneers in motorcycle cornering ABS and stability controls. ........"

[cadd]

Sounds very interesting. My concern: how will the system know if the rider is dragging a knee vs riding in-line with the bike vs riding cross-up

In these three scenarios, the bike can have identical lean angles going the same exact speed. The rider that is hanging off the bike will have more traction in reserves compared to the rider that is riding cross up.

Or maybe I'm just thinking about this all wrong.

[SLOWn60]

I haven't studied any of the systems but I'm guessing there's a few accelerometers in the designs that would detect yaw and determine if the front or rear or both tires are exceeding parameters of sideways slip in relation to the other parameter limits.
Way beyond my finger counting skills but all measurable & calculable by those that can. The challenge is to put it all together in a cost effective and compact package!
That's my guess! ....who needs facts!

[Motofool]

Originally Posted by cadd

.......In these three scenarios, the bike can have identical lean angles going the same exact speed. The rider that is hanging off the bike will have more traction in reserves compared to the rider that is riding cross up.......

Regardless the lean angle of a bike, traction is lost when a contact patch is loaded with excessive parallel-to-the-surface force.
That force could be pure braking, pure acceleration, pure cornering, or a combination of those.

That cornering ABS must be a complicated device that receives many inputs and processes those at light speed prior to modulating speed.

A gyro in the device can measure the physical lean angle (respect to a vertical line) of the frame of the bike, just like gyros measure the banking angle of an airplane respect to the horizon in a turn coordinator instrument.



However, that is not the only factor to consider in order to prevent tire slides.

Hanging off or not, cross and super-elevated (tilt) slope of the curve, surface irregularities, as well as type (new or old asphalt/concrete) and condition (wet or dry) affect the capability of the contact patches to hold on and stay connected to the road.

[HoneyBadgerRy]

I just wanted to add, no matter what the brochure says, I will always trust myself over the ABS or Traction control system. And the fact that motogp riders just sack the throttle wide open and trust that stability control and traction control will work is mind blowing.