CAR TECH

What the Heck is Active Nibble Control?

Apr 24, 2018

Summary
And what’s steering nibble anyway?

We just stumbled upon one of the very weirdest names of all weirdly named things in the world of the automobile. Beware the slight inconvenience of “steering nibble” – Ford was, and they’ve put a little engineering and technological know-how to work to help it from bothering you.

So, just what in the world is steering nibble? Here’s a hint: it’s not what happens when your ride’s steering gets the munchies.

Joe Raad, the Senior Engineer of Electric Power Assist Steering (EPS) at Ford, explains: “Steering nibble is a common term used to describe a steering wheel vibration or shimmy during vehicle operation at medium to high speed.

“A steering ‘nibble’ may be felt in the steering wheel when driving on smooth roads at highway speed and is commonly caused by minor front wheel/tire imbalances, or from slight temporary flat-spotting of tires, from being stationary overnight.”

You yourself may have felt a little shimmy or wobble in the steering from time to time – though an unknown person at an unknown time and place once referred to this sensation as “nibble”, and that term has stuck. But it’s unlikely you’ll experience steering nibble if you’re driving a recent Ford vehicle, equipped with the brand’s Active Nibble Control system. Andrew Brown, Ford’s EPS Features Supervisor, explains how the uniquely named system works:

“Ford has continuously looked for ways to reduce or eliminate nibble, and our chassis engineers developed the idea to do this via electric power steering.

“Since the steering nibble is at the same frequency as the road wheel rotational speed, the electric power steering system can detect that wheel rotational frequency. Then, using our internal sensors inside the electric power steering system, we can determine the amount of steering nibble occurring at the same frequency. We then reduce nibble by applying an opposite torque to the steering system. This allows the system to reject the nibble, while leaving the desired steering wheel torque feedback passed on to the driver.”

In simple terms, it sort of works like noise-cancelling headphones, but with vibrations, not sound waves. Noise-cancelling headphones detect and neutralize unwanted sound patterns from entering the listener’s ears, while Active Nibble Control detects and neutralizes unwanted vibration frequencies that may otherwise travel up to the steering wheel and be detectable to the driver.

Though the source of the term is unknown, it is commonly used today, says Raad, adding “steering nibble is a common term used in dealerships and service shops to describe steering wheel vibration experienced by the customer.”

Do you need to worry, if your steering feels a little bit nibbly? Kelly Trost, Ford’s North America Ride and Handling Lead, says no.

“Nibble is not dangerous; it’s just an annoyance. Tire/wheel imbalance and brake inputs can cause the suspension to resonate, which causes small left-to-right motions in the steering gear, which moves upstream into the steering wheel, creating the torsional input we call ‘nibble’.”

Why develop and create a system to neutralize such a minor inconvenience? Brown explains: “This was driven by customer feedback, but was a very bright idea by engineers Joe Raad and Darrel Recker, on how to fix it with the advent of electric power assist steering.”

Meet the Author

Justin Pritchard is an automotive journalist, consultant, TV presenter, and photographer based in Sudbury, Ontario.