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The World's Lightest Electric Vehicle

kickstarter.com

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Re: The World's Lightest Electric Vehicle

#91

Post by oftenwrong »

hrktb wrote: post #83
ajross wrote: post #53

Earlier quoted context omitted.

It's not so much the brakes being stable, it's the operator's body with its c.g. 1m above the board. A maximum deceleration for tires on a good road is generally 0.6-0.8G. So in order to avoid being (literally) thrown off the board the rider needs to be leaning backwards by 30-40 degrees before applying the brakes. There's no equivalent to this behavior in any other vehicle. In a car you just hit the pedal, on a bike…

In a bike just sqeueezing the handle will also throw you away, especially when downhill. It takes practice as well to be able to move your gravity center backward in emergency brakings.

It is more about using the handlebars to resist your body's forward momentum.

Re: The World's Lightest Electric Vehicle

#92

Post by aggie »

pg wrote: post #66
FrojoS wrote: post #63

Earlier quoted context omitted.

I remember you wrote in an essay, that the Segway 'failed' because it makes people look lazy, like a 'smug', when they ride it and that changing the position to skateboard style might be the only change required. [1] Well, its not a Segway yet, but seem like we're getting there. But maybe this is the optimum already. edit: found it [1] http://www.paulgraham.com/segway.html

Curiously enough there was another startup this batch that did the converse: used Segway-like balancing technology in what will probably turn out to be a better way: http://doublerobotics.com

It seems a dedicated, remote, wheeled iPad, especially like in the gallery example, should take advantage of an external camera with optical zoom. The iPad camera is good for what it is, but the physical dimension constraints don't seem to apply if it's already mounted to a 5-foot robot.

Otherwise, that's really cool.

Re: The World's Lightest Electric Vehicle

#93

Post by zzzmarcus »

MartinCron wrote: post #33
zzzmarcus wrote: post #29

Earlier quoted context omitted.

Absolutely. The weight difference is definitely the biggest difference. I've ridden longboards with both foot and hand brakes. All the hand braking boards I've tried had a cable from the board to the controls and even with that hassle, I much prefer them to the foot brakes. Moving your foot around and trying to get even pressure at 20mph is a lot more tricky than squeezing a lever.

I'm interested in getting into longboarding. Would you be willing to share the name of the hand braking board you've used?

Looks like it's evolved some since I used it, but this is the company: http://www.skatebrake.com/products.html

Re: The World's Lightest Electric Vehicle

#94

Post by skdoo »

duked wrote: post #56
skdoo wrote: post #44

Co-founder here. Feel free to ask questions!

Why the price is so expensive, it would help people to understand and eventually invest?

Two reasons.

1. We're starting with a great longboard - one that would cost over $300 if you bought it alone.

2. We're using advanced and expensive motor and battery technology. The kind seen in electric motorcycles and cars, but never in bikes or scooters.

The reason the price is so high is because we built the first ones for ourselves, not for customers, and we only used the best ingredients. We have no intention of compromising that, even if it means less volume, because the end result is worth it.

Re: The World's Lightest Electric Vehicle

#96

Post by eurleif »

jonnycowboy wrote: post #78
pg wrote: post #67

Earlier quoted context omitted.

Like all technology it will get cheaper. Even now it seems empirically to be a good deal if you can afford it, judging from the reactions of the three YC partners that bought one.

I'd like to add, I love the controller design. That alone must be worth a couple of hundred ;) Does it use bluetooth? I hope it is not a standard RC transmitter because they can get jammed fairly easily (leading to injury and death, etc etc) even on the new(ish) frequency-hopping 2.4Ghz models. PS. are you hiring ? ;)

>they can get jammed fairly easily (leading to injury and death, etc etc)

Wouldn't a failsafe that activated the brakes if contact with the remote were lost pretty much avoid any serious problems? I don't think getting rear-ended should be much of a concern, since the maximum speed is 20 MPH, and cars will (hopefully) be careful behind someone on a skateboard in general.

Re: The World's Lightest Electric Vehicle

#97

Post by skdoo »

vanhowen wrote: post #61
skdoo wrote: post #44

Co-founder here. Feel free to ask questions!

(Ignore the horrible website) What are your thoughts on this? http://www.metro-board.com/ How does your board compare to the metro board? What makes it special?

The weight, power, hill capability, deck flex, handling, design, aesthetic, and interface are very very different. More to come on this topic later.

Re: The World's Lightest Electric Vehicle

#99

Post by zzzmarcus »

ajross wrote: post #53
IanDrake wrote: post #34

Earlier quoted context omitted.

Maybe I'm thinking about it wrong. Slowing down vs. braking, I mean. If I'm going 20mph, "braking" to me means coming to a stop in an equivalent distance as a car or bike going the same speed. Are the brakes that you've used stable at that rate of deceleration?

It's not so much the brakes being stable, it's the operator's body with its c.g. 1m above the board. A maximum deceleration for tires on a good road is generally 0.6-0.8G. So in order to avoid being (literally) thrown off the board the rider needs to be leaning backwards by 30-40 degrees before applying the brakes. There's no equivalent to this behavior in any other vehicle. In a car you just hit the pedal, on a bike…

If you slam on the brakes, yes, you'll fall. However in my experience in practice it is not hard to get used to braking on a longboard. I've done it and seen lots of other people do it without crashing.

You probably don't stop as fast as you would on a car or a bike, but you learn to control the speed you stop at pretty quickly.

I don't think longboarding will ever be as safe as riding a bike, but braking isn't the biggest reason for that.

Re: The World's Lightest Electric Vehicle

#100

Post by TomatoTomato »

JoeAltmaier wrote: post #90
TomatoTomato wrote: post #89

Are batteries quickly replaceable? i.e. If I had a spare battery in my pack, I could change it out and continue on?

Or can it come with a larger pack to begin with? Avoid changing it at all.

If they don't do it, I'm sure someone will hack multiple batteries together and post a how to.
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