How Rivian’s off-roading electric vehicles get their supercar-like feel

How Rivian’s off-roading electric vehicles get their supercar-like feel

Automakers were already experimenting with electrified cars long before Tesla was introduced to the market. Urban commuters who want to save money at the pump will appreciate cars like Toyota’s Prius or Chevrolet’s Volt. These vehicles were followed by the Hyundai Ionic 5 (and later Volkswagen ID.4).

Today’s next frontier is battery-powered off-roading trucks. GMC accelerated its production schedule for the Hummer EV, which features a crab-walking trick made for tight turns on tough terrain, and Ford’s new all-electric F-150 Lightning wasn’t far behind. Chevrolet is following suit with an electric-powered Silverado pickup truck.

Meanwhile, small-batch upstart Rivian has been selling its R1T pickup since 2021 and R1S SUV since 2022–and coming up with new ways to make electric trucks as capable off the pavement as they are on it. The kinetic system is a unique electro-hydraulic roll control system that replaces a mechanical antiroll bar and smoothens out the ride. An anti-roll bar, which is a simple U-shaped metal piece that acts as a torsion Spring, connects the axles to prevent excessive rolling. This is uncomfortable and makes it difficult to control the vehicle.

The company sent teams in both of its vehicles to this year’s all-female Rebelle Rally, the longest rally raid (long distance off-road racing that takes place over several days) in the United States, at over 1,600 miles between Nevada and California. Rivian put their trucks to the test on dirt and rock, and won. Rookie team Lillian Macaruso and Alex Anderson, both engineers for the automaker, placed fourth overall out of 53 teams in an R1T and Rosanna Nuch and Nicole Johnson also performed admirably in the top half of the field in an R1S. Macaruso explained more about Rivian technology to PopSci during a ride along after the competition to explain how it works.

Rivian’s hydraulic roll control provides stiffness when cornering in the same manner (and with similar equipment) as a McLaren 720S supercar. This is no accident: Rivian hired Charles Sanderson, chief engineer at the auto manufacturer in 2018,, and Sanderson integrated the Tenneco-supplied linked hydraulic damer system that he was very familiar with. That means the R1T has a sportscar feel, especially when accelerating, but the system leaves space for a looser fit in situations where articulation–vertical wheel travel, or how far the axle can move up and down– is present.

A typical gas-powered offroad-capable vehicle has a sway bar. This reduces the vehicle’s body roll and “sway”, which helps to stabilize the vehicle’s weight distribution. A weight shift that causes the car to tip is something you don’t want if you’re turning on a racetrack or cresting a dunes. Rivian strives for “living room comfort .”

” by improving the vehicle’s “head toss,” which is the way it shakes while you traverse uneven terrain.

” Essentially, you feel the vehicle tilt or tipping when you turn a corner. The hydraulic system controls this by applying different pressures to each corner. Imagine if you tried to walk up a set stairs with your legs extended and your arms on your sides. One leg gets tired and the others compensate .”

Rivian’s R1T has 800 horsepower and more than 900 pound-feet of torque on tap, and drivers can mash the accelerator and reach 60-mph in a scant three seconds. This is great when speed is the goal. However, four-by-four driving is more difficult to maintain the truck’s integrity. The R1T boasts balanced geometry for its approach, breakover (the angle between the vehicle’s tires and the middle its underbelly), and departure angles matched with a fairly generous ground clearance of 15 inches, giving the truck plenty of poise and steady movement over obstacles on the trail.

The company is monitoring how the truck performs during tough test runs and making adjustments as necessary. Rivian introduced a soft-sand mode to the R1T/R1S earlier this year after Emme Hall and Rebecca Donaghe, long-time Rebelle team members, found the R1T settings to be too restrictive for sand-dune driving during 2021’s rally. While soft sand is fine for driving on hard sand, it is not necessary to switch to soft sand mode. However, floating on top of dunes and on the beach requires more rotation so this mode allows for better control.

“When soft sand mode is activated, it alters how much wheel spin you are able to have,” Macaruso explains. It basically tells the truck that it can dig more because each wheel can be controlled independently. Each motor can control a single wheel and move it in a different way .

While Rivian’s recent recall was caused by an insufficiently torqued steering wheel fastener, investors were alarmed this week. However, the company continues to move forward with its SUV and truck. They’re well positioned to succeed if they can handle the Rebelle Rally.

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