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I remember reading about Goodyear releasing a "spherical wheel" concept in early 2016: http://www.popularmechanics.com/cars/a19747/goodyear-eagle-360-spherical-

I remember reading about Goodyear releasing a "spherical wheel" concept in early 2016: http://www.popularmechanics.com/cars/a19747/goodyear-eagle-360-spherical-tires/ http://www.popularmechanics.com/cars/a19747/goodyear-eagle-3...

tempestn 9y ago
ISTM you could get all the same benefits much more easily using four-wheel independent steering, on regular, cylindrical wheels. The design could also be much more compact by sacrificing fully horizontal motion. (IE if the rear wheels only turned up to +-30 degrees, say.) It could still park very tightly using a zig-zag motion, and in any other situation tighter turning wouldn't be useful. Porsche (and possibly other companies) are already moving in this direction, with newer models featuring computer-controlled rear wheel steering. At low speeds the rear wheels steer in the opposite direction to the front, and at high speeds in the same direction.
- MrFoof 9y ago
  Active rear-wheel steering actually has a far larger history than its recent resurgence from Porsche, actually coming from Japanese manufacturers with mostly hydraulic (not electric) implementations. * Nissan stared offering it with several 1986 Skyline trims, and would also offer it on Z32 300ZXs. * Honda starting offering it on the 1987 Prelude, and also on the Accord starting in 1991. * The 1988 Mazda 626 sedan (predecessor to the Mazda 6) had it. * Toyota offered it in Japan on the Camry/Vista for the 1988 model year. * ... and many, many more. From MPVs to pickup trucks. The modern resurgence started again with Nissan, with several Infiniti models (the M and Q) offering electric versions from around 2006, and it appeared in the R35 GT-R. Though BMW was technically first with the E65 7-series. Porsche got into the game with the 991 911 GT3 (and optional on all 991.2 911s) because it alone hacked 1.5% off of lap times. The benefit of the newer setups is how wonderfully simple it is in terms of parts, complexity, and reliability (and no more hydraulic leaks!) Having driven both the R35 and 991.2s, the difference is pronounced. RWS is one of the reasons why the GT-R could manage itself (it is approaching 4000 pounds) as well as it could around the track, and why the latest 911s I've driven on track were so eager to dive-bomb apexes compared to any other 911 I've ever driven.
  - macintux 9y ago
    I briefly drove a Honda with 4-wheel steering in the early 90s. All I remember is the amazing turning radius.

tempestn 9y ago

ISTM you could get all the same benefits much more easily using four-wheel independent steering, on regular, cylindrical wheels. The design could also be much more compact by sacrificing fully horizontal motion. (IE if the rear wheels only turned up to +-30 degrees, say.) It could still park very tightly using a zig-zag motion, and in any other situation tighter turning wouldn't be useful. Porsche (and possibly other companies) are already moving in this direction, with newer models featuring computer-controlled rear wheel steering. At low speeds the rear wheels steer in the opposite direction to the front, and at high speeds in the same direction.

MrFoof 9y ago
Active rear-wheel steering actually has a far larger history than its recent resurgence from Porsche, actually coming from Japanese manufacturers with mostly hydraulic (not electric) implementations. * Nissan stared offering it with several 1986 Skyline trims, and would also offer it on Z32 300ZXs. * Honda starting offering it on the 1987 Prelude, and also on the Accord starting in 1991. * The 1988 Mazda 626 sedan (predecessor to the Mazda 6) had it. * Toyota offered it in Japan on the Camry/Vista for the 1988 model year. * ... and many, many more. From MPVs to pickup trucks. The modern resurgence started again with Nissan, with several Infiniti models (the M and Q) offering electric versions from around 2006, and it appeared in the R35 GT-R. Though BMW was technically first with the E65 7-series. Porsche got into the game with the 991 911 GT3 (and optional on all 991.2 911s) because it alone hacked 1.5% off of lap times. The benefit of the newer setups is how wonderfully simple it is in terms of parts, complexity, and reliability (and no more hydraulic leaks!) Having driven both the R35 and 991.2s, the difference is pronounced. RWS is one of the reasons why the GT-R could manage itself (it is approaching 4000 pounds) as well as it could around the track, and why the latest 911s I've driven on track were so eager to dive-bomb apexes compared to any other 911 I've ever driven.
- macintux 9y ago
  I briefly drove a Honda with 4-wheel steering in the early 90s. All I remember is the amazing turning radius.