Driven: Mazda’s new G-Vectoring Control system

MAZDA has revealed its all-new dynamics-enhancing G-Vectoring Control system that is designed to improve stability, driveability and comfort, and will be rolled out across the Japanese brand’s passenger car and SUV line-up.

The technology is the first of its kind, according to Mazda, and will debut in the facelifted Mazda3 small car due in Australia in the second half of this year.

It should be followed early next year by the Mazda6 as part of the mid-sizer’s second update since launch, before being rolled out to the rest of the SkyActiv range which covers all models except the BT-50 utility.

Speaking at a demonstration of the system at California’s Mazda Raceway Laguna Seca this week, Mazda Australia managing director Martin Benders confirmed the Mazda3 facelift and said the company was looking forward to the arrival of the first vehicles equipped with G-Vectoring Control.

“We’re excited to have it because with the mid-life change of Mazda3 it doesn’t just get G-Vectoring by itself, it gets retuned suspension and retuned steering so the whole package makes it a big jump,” he said.

“We’re happy because the car improves significantly over the pre-facelifted model.”

In addition to the new technology, Mr Benders said the updated model “will get some body changes and some interior changes”.

He also emphasised that while G-Vectoring Control (GVC) had a beneficial by-product of boosting cabin comfort, the new system’s greatest effect was improving the company’s ‘jinba ittai’ philosophy and the oneness of human and machine acting together.

“It’s only a comfort feature in the sense that if you’re driving you’re less stressed and less fatigued and your passengers are more comfortable because you are driving better and you’re more connected to the car,” he said.

“We’re focusing on (the fact) that G-Vectoring gives you better control of the car and more intuitive control of the car.

“We already focus on chassis dynamics and steering and we’ve lifted that another level with G-Vectoring.”

Unlike other torque vectoring systems which use a combination of braking an inside wheel in corners while applying power to an outside wheel, Mazda’s self-described “revolutionary” system uses an imperceptible reduction of engine torque to sharpen turn-in.

Each time the driver makes a steering input, the GVC system momentarily reduces the amount of fuel being injected, which results in a small torque decrease, that in turn causes the vehicle to decelerate by between 0.001g and, in extreme circumstances, 0.05g.

The reduction in speed is not great enough to be consciously noticed by occupants of the vehicle, but is significant enough to cause the vehicle’s nose to dive, placing an extra 5kg of weight on to each front tyre.

It may not sound like much, but Mazda says the result is a significant improvement to steering effectiveness and a reduction in the number of steering movements a driver has to make to maintain a continuous course.

The guiding principle for the project was what Mazda calls “minimum jerk” or the reduction of sudden movements which simultaneously allows a smoother driving experience for more driving enjoyment and increases cabin comfort.

With a more responsive steering system, Mazda says stability – particularly slippery surfaces – is significantly improved and fewer corrections are needed by the driver, which directly reduces fatigue of all occupants and improves comfort.

While the system has significant benefits for occupant comfort, the GVC technology is primarily focused on sharpening chassis dynamics, which Mazda says has the knock-on effect of improving ride comfort.

The technology has been eight years in the making, requiring detailed analysis of the forces on both a car and its occupants during cornering and, while cracking a complex GVC equation was part of the battle, its latest SkyActiv engine technology was the final piece in the puzzle.

Initial attempts to create the same effect involved trials using a minute force applied by the brake system but the car-maker found the response was too late to create the desired effect.

The latest SkyActiv engine management system is significantly faster than the older technology, allowing a rapid but short torque interruption.

No mechanical changes were required to implement the system to Mazda’s test vehicles, but for the production versions the system will be enhanced by a chassis retune to enhance the positive effects of G-Vectoring.

The only exception is the Mazda6, which coincidentally has a perfectly matched suspension set-up as standard.

The simplicity of the final system defies the years spent researching and honing GVC as well as the effectiveness of the technology, but Mazda gave GoAuto an opportunity to evaluate the changes with a specially rigged Mazda6 prototype at Laguna Seca.

A retrofitted push button allowed the G-Vectoring system to be switched on and off during a series of demonstrations, starting with a simple low-speed negotiation of an oval circuit.

Initially, it was hard to distinguish the changes in either our driving or the behaviour of the vehicle other than perhaps a reduction in mid-corner corrections, but an on-board Mazda data analyst armed with a laptop and direct line into the vehicle’s sensors proved the effect in black, blue and white.

The initial laps with GVC assistance plotted a much smoother graph line in both steering angle and steering speed, confirming that we were moving the steering wheel through a smaller number of degrees and more slowly with Mazda’s new system turned on.

With water applied, the same track became slippery and representative of a typical rain-soaked road and allowed us to detect the effect of the system more obviously. Switched on, the nose turned in more responsively and held a tighter line against the marker cones.

Again, the data suggested we were working harder with the system inactive and maintained a smoother line with it on.

While the car could be provoked to understeer in both cases, with GVC active we felt a greater sense of confidence in the front end and that it would do as it was told – a point Mazda calls the ‘moment of fear’.

The more tests we threw at the system, the more the GVC effect became apparent, including a rapid lane-change exercise and a crack at the full Laguna Seca track.

The result in steering responsiveness may only be perceptible when really looking for it, but Mazda says that is the beauty of it.

We agree implicitly, especially when bearing down on the intimidating Corkscrew which requires all the confidence you can muster.

Perhaps the most noticeable effect, however, was highlighted by a less adrenalin-fuelled drive along one of California’s straighter roads where a fewer number of steering movements were clearly necessary to keep the Mazda6 on a constant course.

The effect is almost eerily effective when you are looking for it but remarkably normal when you are not.

The critical difference between Mazda’s GVC and all other torque vectoring systems (forms of which Mazda also employs) is that G-Vectoring is enhancing the drive characteristics with every individual turn of the wheel and under all driving conditions.

All other systems that use individual wheel braking and torque distribution do not intervene until the vehicle is near or at the ragged fringes of adhesion, whereas the Mazda innovation is far more passive and complementary to a well-tuned suspension.

When it is wheeled out in the Mazda range starting with the Mazda3 and Mazda6, most drivers will probably not directly notice the G-Vectoring Control technology.

But like many other advances in inconspicuous vehicle technology such as cylinder deactivation and cabin noise cancellation, sometimes the imperceptible changes have the most significant effect.