Dig Mode will join Tank Mode, which was shown before
This drive mode makes both of the rear wheels spin in different directions
This is possible due to the R1S and R1T’s quad motor setup
Due to their completely different drivetrains, electric vehicles are capable of doing many things that would be very difficult to achieve with combustion-engined vehicles.
One of those things is turning on the spot, without moving forward or backward. A number of automakers teased this capability, especially those who make electric trucks, such as GMC and Rivian.
This last company previously showed an R1T doing a tank turn and a patent that was recently unveiled could provide another way to steer the electric truck.
Indeed, the patents pertain to a new drive mode called “Dig Mode” which would make the inside rear wheel spin in reverse while the other three wheels are going forward, which could help the vehicle pivot around its rear wheel.
Rivian doesn’t explain why this would be useful in addition to the capability of doing a tank turn, but its name could be a clue. Indeed, using this drive mode could help the vehicle get moving again if it becomes stuck in sand, snow or mud.
Unlike the tank turn, which makes both of the wheels on one side spin backward while the other two spin forward, this mode would require drivers to turn the steering wheel towards the intended direction.
Both of those capabilities make use of the truck’s quad motor setup, which makes it possible to control the movements of each wheel separately.
Since Rivian is currently developing its own in-house powertrain which will only use two motors, one per axle, it is possible that this technology will never be offered to the public.
This could also be why no production Rivian trucks have been able to do tank turns despite the company having made quite a big deal of this feature before production started.
Source: Rivian Forums