[QUOTE=Electictracer;285171]
Quote:
Originally Posted by Ken Fry
1. The issue can be seen by watching someone start out on an Ecomobile or Monotracer. Unlike a motorcycle, which the rider naturally makes vertical with respect to gravity at a stop, enclosed motorcycles (so far) list at a stop to be perpendicular to the road, which is typically crowned. So the driver has to first get the wheels directly under the CG, which requires a swerve. If the bike is leaning to the right, the driver must steer to the right. If there is a car immediately to the right, this is a problem.
In a normal motorcycle, this stuff is so easy that it requires no thought and almost no effort: even if you are leaning slightly at a stop, a tiny push to vertical is simple.QUOTE]
This is very insightful. I wish I had read this about 6 months ago.
My plan with my outriggers is to have torsion springs with an air shock holding down the wheels. The start out lean would be less dramatic this way, then say if your wheels where 1 inch off the ground when straight up. The crown in the road is something I did not consider. I can see the difficulty in correcting this lean on start out. It will be interesting to how big a problem this is.
Oregon commuter is the thread name for project if interested.
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I'll post a note here (and on your Oregon thread) I sent to Visionary, who asked for driving impressions, etc. It highlights some of the issues to consider:
Hi Pete,
Looks like a pretty cool project! My main caution is that the vehicle should be vertical with respect to gravity when you come to a stop. The common alternative (perpendicular to the road surface) usually means that the bike is leaning when stopped (itself a little odd feeling) and so you must swerve to get the contact patches under the CG. This takes Monotracer drivers a while to learn, and even then, they still swerve and wobble, using up road space that might not be available.
I didn't spend a great deal of time on linkages before deciding to go with three wheels (just drive it like a car) but found that even with the outriggers deployable independently, it was hard to get the leverages right to permit both quick deployment and enough force to have good control if the vehicle started to lean too much. If the system were powered (as in power steering, with good force feedback) then this would not be an issue -- just have the outriggers reflect foot position.
My outriggers had casters for wheels, so that as they moved toward and away from centerline during balancing they did not create large drag, the way a forward facing wheel would. On the Ecomobile system, for example, tilting right and left (if possible) would cause a lot of tire scrub (which hydraulics could overcome, but human power could not).
You will need to be able to adapt to the situation in which there is a four inch deep pothole right where you need to have an outrigger (or in the path of an outrigger as you start to move).
I thought the idea of having feet come out the bottom was potentially unsafe, (as well as less than ideal aerodynamically) but it might be a simpler way to deal with balancing when stopped.
I'm an old roadracer, and familiar with countersteering, and I understand the physics of driving like a car with the outriggers down (steer right to go right) and driving like a motorcycle with the outriggers up (steer left to go right). But in actual operation of the vehicle, I found I could get out of synch. My seat was very low (6") off the ground, so roll inertia was low, and as a result the response time to control inputs was short (the roll rate was pretty high). Crashed once by getting out of synch -- kind of like the pilot induced oscillations that can happen with airplanes, especially during landings -- in my case right left right left right left boom.
I have not driven a Monotracer, but if you can find one, doing so would be helpful, I'd think.
That's about all I can think of right now, but if you have questions, please ask... and I'll try to respond more quickly. Actually a better address is
ken@zingcars.com.
Regards,
Ken