Flex4 System Leads Magna's Wave of New Fuel-Saving Technologies

October 23, 2014

Kami Buchholz

Magna's Actimax features fully active, electro-mechanical clutch actuation controlled by an integrated electronic control unit to provide variable torque between the front and rear axles. Current production applications include the Hyundai Genesis and BMW 3-, 5-, 7-Series. A two-speed version is used in the Jeep Grand Cherokee and Chevrolet Silverado.

A new drivetrain technology that's soon to enter production will provide truck- and car-based platform vehicles a fuel efficiency boost.

The next evolution of Magna Powertrain’s fully active Actimax 4WD technology, providing variable torque distribution between the front and rear axles, will have a fuel-savvy attitude.

The illustration depicts how Magna's Flex4 technology can react to changing road conditions. (For more images, click on the small arrow at the upper right corner of this image.)

“We recently secured our first customer for Flex4, a fast-acting active disconnect system that uses our Actimax active clutch technology," reported John Zalewski, the company's Global Product Manager of Axle Drives and Chassis Modules. The Flex4 system enables the traction-coupling clutch to be opened all the way, disconnecting the axle from the driveshaft. According to Zalewski, the patent-pending system can deliver a 4-7% fuel economy gain, depending on vehicle type.

The system debuts in 2016 on a front-drive-based AWD vehicle.

Automotive Engineering recently spoke with Magna engineers and tested various production 4WD and AWD systems during a media event at The Mounds Off-Road Vehicle Park near Flint, MI.

Since a typical 4WD system weighs approximately 110 lb (50 kg), trimming weight in ways that will not adversely affect performance is important.

“Although this isn’t something we’ve applied to production drivetrain products yet, we’re looking at using the patented High-Q-Cast vacuum high-pressure aluminum die casting process from Magna’s Cosma group to produce the Flex4’s housing," Zalewski told Automotive Engineering. "If the process proves to be production-feasible for this application, it will allow us to make 2-mm (.07-in) walls instead of the typical 3-mm to 3.5-mm (.11- to .13-in) walls,” he said.

Magna Powertain and Magna Electronics engineers are joining forces to put 4WD/AWD into the realm of semi-autonomous vehicle activity. “We’re in the R&D stage now with using the vehicle’s camera-based vision system to engage or disengage automatically the 4WD/AWD system,” Zalewski said.

An off-road ride and drive program for the media featured vehicles equipped with Magna technology. This Jeep Wrangler tackles a mud pit with Magna's standard 241 transfer case, a manual shift transfer case with 2.72:1 low gear ratio as well as 2WD, 4-low, and 4-high operating modes.

The supplier’s commercially available vision system features a proprietary camera, developed and produced by Magna, and an image processing sub-system.

According to Chris Van Dan Elzen, Director of Machine Vision Systems at Magna Electronics, “The image processing takes the video stream from the camera and mines it for information, (such as) lane position, objects ahead, traffic signs, headlights/taillights.”

An advanced image processing vision system that networks with the vehicle’s chassis controls could expand the active safety scope and provide a fuel efficiency payback.

Said Zalewski, “If the vehicle is in 2WD and is approaching black ice, the vision system’s detection of glare on the roadway could prompt an automatic switch into AWD to prevent a skid issue. The ability to determine whether or not AWD is the best option, based on the terrain’s condition, also could yield fuel economy gains.”

Added Van Dan Elzen, “Curves, speed limits, and other information can be taken into consideration with the ultimate goal of maximizing the use of 2WD whenever conditions permit.”