Toyota's iRoad concept...

[gone-ot]

Originally Posted by NeilBlanchard

Okay, this is unexpected - the i-Road steers with the rear wheel - here's a video:

AOL On - Watch the Toyota I-Road Turn and Lean

...Forklift drivers would probably love it!

[botsapper]

Originally Posted by NeilBlanchard

Okay, this is unexpected - the i-Road steers with the rear wheel - here's a video:

AOL On - Watch the Toyota I-Road Turn and Lean

Great urban maneuverability and ..solves the need for very basic front wheel aero-covers.

[freebeard]

Okay, this is unexpected - the i-Road steers with the rear wheel

Revenge of the Dymaxion!

[NeilBlanchard]

There are still problems with rear wheel steering:

ApteraForum.com - Unofficial Aptera Car Forum - View Single Post - Toyota i-Road Electric 2-Seater

The dynamic instability can probably be managed by computerized "stab aug", but the obstacle avoidance issue remains. Suppose you see a pole or shopping cart not too far in front of your car. Normally, you crank the wheel and the front of the car moves sideways at about a 30-degree angle, avoiding the obstacle while the back of the car follows on a circle INSIDE the front turning circle, thus also missing the obstacle. Note how much harder it is to perform the same avoidance while backing up. Full steering lock only causes the rear end to start tracing a large circle, but does not immediately change its direction like the front wheels do; meanwhile the front end is traveling off at an angle that may hit something. Even if you manage to avoid the obstacle with the rear end, the front end is traveling on an OUTSIDE circle that could still hit the obstacle (or something else). Now imagine this was your normal forward driving experience. You'd be doing a lot of backing and filling for what would normally be a direct avoidance maneuver.

Pat Q

[freebeard]

Full steering lock only causes the rear end to start tracing a large circle, but does not immediately change its direction like the front wheels do; meanwhile the front end is traveling off at an angle that may hit something.

This may be true, but it's hard for me to see it. Wouldn't it be more like "Full steering lock only causes the rear end to start tracing a large circle, which immediately changes its direction like the front wheels do; meanwhile the rear end is traveling off at an angle that may hit something."

Someone should test a 3-wheel steering carver (leaner). One could turn off each feature and see which one gives the better result. I suspect the 3-wheel steer would allow wider treads and better cornering, but the carver with it's narrow contact patch would be better for economy.

[NeilBlanchard]

There is video of the i-Road in motion and steering. The leaning is also done by wire, so it may be that the wider front track (when leaned) means it effectively steers somewhat? But at low speeds (when parking) it can't lean much, if at all - because that would throw the driver for a loop, so to speak!

[gone-ot]

Originally Posted by NeilBlanchard

There is video of the i-Road in motion and steering. The leaning is also done by wire, so it may be that the wider front track (when leaned) means it effectively steers somewhat? But at low speeds (when parking) it can't lean much, if at all - because that would throw the driver for a loop, so to speak!

...and spill their McDonalds' Mocha Cappachino coffee out of its cup-holder (wink,wink).

[freebeard]

The real test would be the X-prize double lane change test.