skyote

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Brake are applied (lights are on) until they get towards the bottom of the hill at the end of the clip.
Yep, and doesn't appear that it's using the mechanical brakes either, as evidenced by the front left tire at 0:04.





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DucRider

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Yep, and doesn't appear that it's using the mechanical brakes either, as evidenced by the front left tire at 0:04.
The tire rotation actually reverses for a moment in the video which implies the motors are using energy to control the descent. As motor speed drops, regen also drops to non-existent and energy must be applied thru the motor(s) to slow/stop a vehicle (or wheel).
 

DuckTruck

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If it's true that a picture is worth a 1,000 words, you guys are well on your way to many multiples of that with all of the information and observations you've already gleaned from this short video. It's also great to see the Rivian take that big rock to the underbelly without issue. I'm sure glad the underarmor was included with the L.E. That was a very nice call by the company.
 

staples

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Yes the rock hit the bottom of the truck, but we really don't know if it caused any damage.
 

eemri

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I wouldn't necessarily expect the wheels to stop spinning completely as that would imply the motors are being used to apply a reverse torque to prevent them from spinning freely which is slightly wasteful. Or perhaps they are appyling the mechanical brakes? I would certainly expect the motors to disengage in this scenario but am somewhat surprised the wheel doesn't continue to spin freely. Makes me wonder if they found a good reason to actually "brake" the lifted wheel or if this was done for customer perception (especially after all the comments about the tires spinning up in response to earlier AZ offroad videos).
My guess is that since they're going downhill, they're trailing the brakes. So when the wheel is in the air, it doesn't take much brake pressure to stop a wheel from spinning. It seems the brake lights are also on so that's my guess.
 

electruck

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My guess is that since they're going downhill, they're trailing the brakes. So when the wheel is in the air, it doesn't take much brake pressure to stop a wheel from spinning. It seems the brake lights are also on so that's my guess.
Keep reading the replies after mine where it was pointed out that the wheels do indeed spin backwards briefly.
 

Mark K

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My guess is that since they're going downhill, they're trailing the brakes. So when the wheel is in the air, it doesn't take much brake pressure to stop a wheel from spinning. It seems the brake lights are also on so that's my guess.
I thought that all electric vehicles now were required to turn on the brake lights when the vehicle is in regeneration mode. I don't know what "trailing the brakes" means but I expect that it wouldn't be necessary in this situation to touch the brakes at all.
 

Bumble1978

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There's a questionable chuck-chuck-chuck-chuck noise at the end...likely the Flux Capacitor reengaging with the Chromocentric diverter? Or the camera person really didn't want to be left in the middle of the AZ Desert...and wanted a ride home?!?!? :clap:
 

skyote

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Or the camera person really didn't want to be left in the middle of the AZ Desert...and wanted a ride home?!?!? :clap:
Noticed that too, & definitely sounded like footsteps to me.
 

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