Meh...this showed up on some other forum a couple days ago. 50 miles per hour...right. That'd be a steep hill.
I'm sure it is fairly stable. As he points out, your COG is below the axles. It's also very complicated, huge, weighs 200 lbs, and won't fit on my roof rack. Oh, and in case anyone didn't notice, the drivetrains are disconnected left and right. That appears to be how one steers, which seems slightly ungainly.
He ends his demo video with a comment along the lines of "so we're just looking for a couple million dollars investment and we'll be ready to produce these things." I think that's the same line Moller used when he showed off drawings of his sky car 40 years ago...and 30 years ago, and 20 years ago, and 10 years ago, and last year.
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