Rivian R1T is the electric pickup truck the world needs

One problem with using in-wheel motors or axle motors is that limits the motor to running at exactly the same RPM speed as the wheels. Generally speaking, electric motors work more efficiently and more smoothly when they are run at higher speed, which is why most EVs have the electric motor connected to the drivetrain with a reduction gearset, to allow the motor to run at a higher speed than the wheels.

Electric motors which run at the (relatively) slow speed of the wheels also have problems with cogging:

Cogging torque of electrical motors is the [torque] due to the interaction between the permanent magnets of the rotor and the stator slots of a Permanent Magnet (PM) machine... Cogging torque is an undesirable component for the operation of such a motor. It is especially prominent at lower speeds, with the symptom of jerkiness [when used to propel a vehicle, rather than smooth forward motion]. -- Wikipedia
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If the R1T (I mistakenly called it the "RT1" above) and the R1S have 4 smaller inboard motors, then does each have a separate reduction gearset to avoid the various problems of limiting an electric motor to running at the same RPM speed as the wheels? Or does Rivian accept all the problems and limitations of slaving the speed of the motors to that of the wheels?

Either way, the problems associated with using 4 separate motors are going to drive up the complexity and cost of the vehicle, and possibly or even probably make it more prone to mechanical breakdown.

As I've implied, I won't be at all surprised if Rivian switches to two inboard electric motors for the production vehicle.
 
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I left out the reduction gears from that equation. Anyway, here is a shot of the R1T skateboard where you can just make out the motors in the front.
Rivian-R1T-skateboard.webp
 
Pushmi-Pullyu said:
One problem with using in-wheel motors or axle motors is that limits the motor to running at exactly the same RPM speed as the wheels. Generally speaking, electric motors work more efficiently and more smoothly when they are run at higher speed, which is why most EVs have the electric motor connected to the drivetrain with a reduction gearset, to allow the motor to run at a higher speed than the wheels.

Electric motors which run at the (relatively) slow speed of the wheels also have problems with cogging:

Cogging torque of electrical motors is the [torque] due to the interaction between the permanent magnets of the rotor and the stator slots of a Permanent Magnet (PM) machine... Cogging torque is an undesirable component for the operation of such a motor. It is especially prominent at lower speeds, with the symptom of jerkiness [when used to propel a vehicle, rather than smooth forward motion]. -- Wikipedia
​
If the R1T (I mistakenly called it the "RT1" above) and the R1S have 4 smaller inboard motors, then does each have a separate reduction gearset to avoid the various problems of limiting an electric motor to running at the same RPM speed as the wheels? Or does Rivian accept all the problems and limitations of slaving the speed of the motors to that of the wheels?

Either way, the problems associated with using 4 separate motors are going to drive up the complexity and cost of the vehicle, and possibly or even probably make it more prone to mechanical breakdown.

As I've implied, I won't be at all surprised if Rivian switches to two inboard electric motors for the production vehicle.
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Here's a better look from the underside.

upload_2018-11-30_12-42-26.webp
 
Thanks Domenick! :)

Obviously those are inboard twin motors using, as RLXXI said, CV joints enable the drive half-shafts to carry power to the wheels... which I believe is the standard setup for front-wheel-drive cars and light trucks.

But I don't know enough about EV powertrains to be able to tell, from that photo, if there are reduction gearsets between the motors and the drive half-shafts in that photo. I've seen photos of such gearsets but I don't know how large they are. Obviously they are far simpler, and thus can be much smaller, than a gasmobile's multi-gear transmission, but I don't know how much smaller.
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Here's pic of a YASA motor hooked to a reduction gearbox from this article. They're relatively compact. Or at least, can be.

1166_Integrated_Electric_Vehicle_Transmission_Rear_Left.jpg
 
Pushmi-Pullyu said:
Thanks Domenick! :)

Obviously those are inboard twin motors using, as RLXXI said, CV joints enable the drive half-shafts to carry power to the wheels... which I believe is the standard setup for front-wheel-drive cars and light trucks.

But I don't know enough about EV powertrains to be able to tell, from that photo, if there are reduction gearsets between the motors and the drive half-shafts in that photo. I've seen photos of such gearsets but I don't know how large they are. Obviously they are far simpler, and thus can be much smaller, than a gasmobile's multi-gear transmission, but I don't know how much smaller.
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Given how the torque at the wheels is 14000 Nm and the torque at the motors is 1120 Nm, there has to be gears with 12.5 to 1 ratio somewhere.
 
Pushmi-Pullyu said:
I think the Bollinger B1 is the one with the frunk which is going to be hard to beat!

fbTSj2m.jpg


If a "tailgate" is on the front, does that make it a frontgate? ;)

Anyway, I think putting a gate at the front of a BEV's front storage space is brilliant!
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They need to make sure that headgate is watertight, not just for rain but when the truck is pushing through deep water. Any water that gets in there drains directly inside the truck through the front to back tunnel.
 
Tid said:
They need to make sure that headgate is watertight, not just for rain but when the truck is pushing through deep water. Any water that gets in there drains directly inside the truck through the front to back tunnel.
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That would be a real design challenge. Pickup tailgates are not watertight. Perhaps a more practical solution would be to put a watertight door at the front of the tunnel.
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Does anyone know the width of the bed? I have seen the length at 55" but curious if you would be able to fit sheetgoods flat in the back. Too many midsized trucks can't do this due to wheel well intrusion (with the exception of the Ridgeline). Thx
 
Jfkm said:
Does anyone know the width of the bed? I have seen the length at 55" but curious if you would be able to fit sheetgoods flat in the back. Too many midsized trucks can't do this due to wheel well intrusion (with the exception of the Ridgeline). Thx
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I don't know the exact width between the wheel wells, but I've seen it repeatedly claimed that you can put uncut 4' x 8' sheets of plywood in the bed of the R1T with the tailgate down.
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Busiek said:
That's poor. how about a regular cab with an 8' bed??
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That doesn't seem to be in the cards at this point. Remember, they aren't really targeting the "work truck" market with this. It's more for playing. Like, throw all your camping gear and kayaks in it and get out of the city.
 
Roughly 17% of the US market is pickup trucks with a average price at sale of 52k. What market is Rivian going after with a 62k four door "looks like a pickup" truck?

It tows 5,000kg, that's full size pickup range.

Regardless I love the R1T and the box's it checks on my dream vehicle list are all there.

1. 400+ mile range
2. Seats 5 comfortably
3. Extreme utility (70+ft³ cargo capacity)
4. Extreme straight line speed
5. Looks great!
6. Autonomous driving (whatever level)

Where the Model S was only up against full size luxury cars, it also catered to the speed freaks and was able to grab a substantial market share it occupied with the help of louring M5 and E63 fans to EV's.

Rivian and the R1T can do the same. Even if they're only in roughly the tail end of the pickup truck bell curve as far as price point 62k+, I'm sure the R1T will steal a ton of Range Rover/Land Rover Sales, high end luxury pickups, Yukon Denali's,
Escalades, and other 70k SUV's let alone four door pickup trucks. Which is well beyond what the Model S did.

Rivian's R1T is genius on product placement alone for that reason, not to mention that the best EV would ideally be what is the hallmark of ICE fuel inefficiency... A truck!

So whatever market the R1T demographic is appealing to I'm definitely in it.
 
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