Twin clutch AWD + Torque vectoring explanation?

Freeskierdude

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I'm having a hard time looking for a source on how a twin-clutch AWD system works. Can somebody explain it or point me to a good source? Is a twin-clutch AWD system the same as a limited-slip? Or is a limited-slip exclusive to a solid rear axle vehicle? Schematics? My friend who is a car guy is asking me these questions but he lives in the land of 90's solid axels. sorry, this should be in the technical section but I can't change it now.





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Raymo

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https://www.autoanything.com/resources/bronco-sport-explorer-2-0-or-just-bs/

Off-road traction

More than traction control, new AWD systems are getting very good at optimizing traction. Take for example the Bronco Sports optional AWD system. Supplied by GKN, it’s an always active AWD system that can fully decouple. Dropping a transfer case, the Bronco Sport uses a Power Transfer Unit or PTU that attaches to transaxle and sends power to the Rear Drive Module, or RDM.

The RDM has 2 clutches, one on each axle shaft that takes the torque from the prop shaft and distributes it to the wheel that needs it. These 2 clutches handle front-to-rear as well as side-to-side speed and torque biases, effectively eliminating 2 differentials, the center, and rear. When AWD is commanded, such as when the “center lock” button is pressed, the 2 rear RDM clutches engage at the same time, allowing torque to go to the rear axle. When turning sharply, the computer disengages the clutch on the inside wheel of the RDM allowing it to slip to deal with the speed difference a differential would normally handle. When you “lock” the “rear diff” you are commanding more pressure more often to those clutches. The buttons are programming tricks to tell the computer you prefer traction over smooth on-road driving but “lock” nothing, not really.

Even when “locked” the systems will know to allow the required slip for turning for example. Despite this, the system is very effective, allowing for at least half and probably more up to 70% or so of the engine torque to go to the rear axle and “almost all” that torque to go to a single rear wheel according to Ford. The front differential is your run-of-the-mill open type and is managed through braking individual wheels to simulate traction on a slipping wheel and allow more torque to go to a gripping one.
 

Excape

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Cabezone

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Freeskierdude

Freeskierdude

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Thank you so much!!! This helps so much!
 

CrookedLetta

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The RS is different as it is overdriven but I can say it works very well in that vehicle. Unique set up as it is basically a spool design with the give being wet clutch packs actuated with hydraulics created desired TQ distribution.
 

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