Honda Motorcycle Lane Keep Assist

[Admin]

As you would imagine, something as complicated as Lane Keep Assist on a motorcycle requires many systems to work in unison for success. (Honda/)

With an ambitious plan to end all motorcycle fatalities involving its bikes by 2050, Honda is understandably hard at work developing new safety systems for motorcycles. We’ve already seen patents illustrating plans for semi-autonomous machines that are clearly still years or even decades from reality, but Honda also has a more real-world motorcycle safety tech under development in the form of a lane-keep assist system (LKAS).

Most of us are used to the idea of having a computer step in to help with braking in the form of ABS. More recently, most bikes have also gained ride-by-wire throttles, eliminating the mechanical link between the twistgrip and butterfly and allowing manufacturers to tailor throttle response and power delivery as well as ushering in the era of traction control. But even though both those developments have led to better bikes, the idea of allowing a computer to get involved with steering as well goes against the grain for most of us.

Fortunately, Honda’s engineers are well aware of this resistance. More often than not the engineers who design motorcycles also ride them, and are undoubtedly as concerned as anyone about the issue of taking control away from the rider and putting it in the hands of a computer. As such, the patents for Honda’s motorcycle LKAS put an emphasis on the system’s subtlety and its willingness to cede control back to the rider at the first hint of a conflicting input at the handlebars.

Like other motorcycle safety systems that Honda has under development, the LKAS concept relies on a combination of a front camera and a radar sensor to monitor its surroundings, in particular keeping an eye on road markings and other vehicles ahead. It’s an idea that will be familiar to anyone who’s driven or owned a car with a similar system, but applying the idea to a bike adds a layer of complexity because steering on two wheels isn’t as simple as turning the steering wheel of a car.

The steering actuator is very similar to a steering damper in appearance, except that it is making inputs to the steering instead of damping sharp unwanted inputs. (Honda/)

The mechanical side of the LKAS system is essentially a more sophisticated version of an active steering damper. The idea of steering dampers that can change their damping properties via computer control isn’t new, but instead of simply damping movement, Honda’s LKAS unit can actively combat it, using an electronic actuator rather than a damper. The unit itself, illustrated in the patent, is fairly compact and connects to the triple clamps via a simple linkage, allowing it to mount on the bike’s frame. There’s no reason the same unit couldn’t be used on a wide variety of models.

Like the steering-assist system that Yamaha revealed earlier this year, and is currently testing on its works motocross bikes racing in Japan, the Honda steering actuator uses a magnetostrictive torque sensor to measure the input on the bars and to distinguish that from external forces (for instance, those caused by bumps in the road surface). As such, it can tell the difference between an intentional move made by the rider and an unwanted one.

Unlike an automotive system that simply turns the steering wheel to get back on track, the LKAS gives a quick countersteering input to lean the bike back into the center of the lane. (Honda/)

Like familiar car-based LKAS systems, if the camera notices you’re drifting out of the lane without a positive movement on the bars, it can correct that drift. Unlike a car system, which simply moves the wheel to steer back into the center of the lane, the bike version countersteers, turning the bars briefly in the opposite direction to change the bike’s lean angle and get it back on course. It’s tied into an inertial-measurement unit of the sort already used on many bikes, monitoring roll, pitch, and yaw, as well as sensors for acceleration, speed, throttle position, steering angle, steering torque, and even suspension stroke. As soon as the system corrects the bike’s drift out of lane with a brief moment of countersteering, it disengages again to return full control to the rider, and if the magnetostrictive sensor picks up an intentional steering input from the rider, it also instantly disengages. The idea is that you shouldn’t really notice it’s there at all.

As well as acting as an LKAS system, the setup is intended to act as power steering, rather like the setup Yamaha is developing to assist inputs that you make at the bars. The radar element of the system, which is likely to also be tied to an adaptive cruise control system, is intended to help you take avoidance action if the vehicle ahead suddenly stops, slows, or swerves. In that situation, if there’s no avoiding action already taken by the rider, the computer controlling the system makes a decision whether it needs to steer around the danger, and whether it’s safer to go to the left or the right, before making that move automatically. Even then, however, if the rider makes his or her own input at the bars, the human judgment is automatically given priority, disengaging the auto-steering system.

There are quite a few scenarios in which the system relinquishes control to the rider. A bumpy road surface is one of them, as is anytime it feels the rider trying to override its decision. (Honda/)

Whether this sort of tech has the same potential to reduce accidents as ABS and traction control remains to be seen, but it’s clearer than ever that it’s something multiple manufacturers are working on and Honda’s patents show that the designers are determined to make it as unobtrusive as possible, giving the rider the ability to overrule it at every stage and really only stepping in when the person who’s meant to be in control isn’t paying enough attention.

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[Mickly]

No no no, just no !!
I’ve got lane departure in my current car and when it tries to re-centre I really gives me the shits & I over compensate as I don’t initially realise what’s happening and end up swerving, this would be a disaster on a bike & would probably have me off.

I do use my indicators but sometimes it has a mind of its own.