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Jeep May Have Told Us What Hummer's "Crab Mode" Is...15 Years Ago

1347 Views 4 Replies 3 Participants Last post by  StillHummer
So by total chance, I came across this today. Meet the Jeep Hurricane Concept.

This was a 2005 concept car from Jeep that features TWO Hemi engines, one in the front, and one in the rear. Not unlike two electric motors...sound familiar?

Anyways, the Jeep used a four-wheel steering system to turn both front wheels in towards the front of the car, and both rear wheels in towards the back of the car. Then using some special differentials connected to the two engines, the wheels began to spin and move the car in a perfect circle. Jeep called this "Crab Steer."

Unlike Rivian's "Tank Turn," which just has the motors turn opposite directions both front and back without turning the wheels...I think the Hummer may do something close, but with all wheels turned into a perfect circle. It requires FAR less power to do this, as Rivian's system really only works on loose dirt or sand, where wheel resistance is low.

Check out the article, and especially the video. Depending on how possible this is to do with 3 electric motors (I assume that the front motor can choose to drive just one of the front wheels, with the two motors in the rear powering each rear wheel independently) ...I really believe this is exactly what Crab Mode is.

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Here;s a diagram of how it worked, for interest.

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That seems way too elaborate for a production model. My guess is that it will be more similar to the Rivian's tank turn.

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That seems way too elaborate for a production model. My guess is that it will be more similar to the Rivian's tank turn.
That's what I thought too, but it's not conventionally possible with the Hummer's current motor setup. Rivian has a motor at each wheel, which is what makes Tank Turn possible. Hummer maxes out at 3 motors. They could theoretically make some kind of differential that splits the torque between the front wheels and sends them different directions when Crab Mode is engaged, but that seems too complex to attempt, especially for an off-roader.

Remember, the Hurricane system is complex because it uses gas engines...the entire system becomes much more plausible with electric motors. You can essentially cut out everything in that image between the engines. It's all direct placement, motor to wheel, not motor, to transmission, to differential one, to differential two, to wheel hub, etc.

The only reason I mentioned this was because it fits with something a journalist said at the March EV event GM had - he said it looked capable of 4 wheel steering, and the wheel wells were huge. That sounds like they're leaving open room for high-degree turning at all 4 wheels. Guess we'll have to wait and see tomorrow!
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