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Comment by orblivion | Hacker News Reader

But you still can't ride slowly downhill for too long without it cutting out the brakes to prevent overcharging?

This is only an issue if the battery is already fully charged. I live on a very steep incline ~18%, I know if I charge my battery 100% that I can't ride it downhill for the first leg of my trip, I simply unplug it a few minutes early to leave room for the extra charge that comes from riding it downhill first. Really not a big deal at all.

I can't believe this is an actual problem. Too much charge...

Anyway, wouldn't it make more sense to walk a bit when you are on a downhill, less tiresome than going uphill.

I mean you're generating energy. It's like your filling up a bucket. Once the bucket is full what can you do with the excess?

Someone mentioned already that trains do that, but that would require a heating element, maybe a fan, and of course the chance of melting things, or catching stuff on fire if not designed properly.

No shortage of air to move over the heatsink since you're only using the brakes if you're moving, so you shouldn't need a fan.

But there's definitely a fire risk if you're not careful. And you'd have people burning themselves when they pick up the board.

Talking from a position of extreme ignorance here, but assuming they've got some genre of H-Bridge in their brushless DC driver they should be able to pulse the motor in reverse to support braking. (also making assumptions as to how the regen braking is hooked up here...)

They could switch to brakes that drain energy. That's a lot more work I'm sure, and maybe they needed an MVP. But for version 2 I'd think they'd make it a priority.

I think this board is really cool but until they fix this I'm not in the market.

I've got 500 miles on my board and it has never been a problem, just something to be aware of. Adding mechanical brakes would involve one or two servos, two sets of brake disks and pads, and a few dozen more parts. That's a lot of hardware for a problem that few experience so it will likely never happen.

I've been seriously considering buying one, but can't decide if the brakes cutting out will be a problem.

I live at the top of a steep hill, so it sounds like I wouldn't be able to leave my house on a full charge. Maybe I could just do a bit of trial and error to figure out how much "room" I need for the downhill?

The main issue with this style of brake is dissipating the huge amount of energy generated from a person riding down a long steep grade, in braking components that need to remain small and lightweight.

If it were an annoyance, sure, but this is a safety issue.

If they at least gave you a clear warning of some sort that would be okay actually.

There is a clear warning. The board will start beeping like a m'fer. I live in Seattle and there are lots of hills that I go down. I usually make sure to charge the board to 90% instead of 100%. I agree that the brakes could be better - having the motor brake instead of an actual disc brake does sometimes cause a bad side-turning skid, but it's nothing that can't be dealt with diligently by knowing how to ride. I've never fell off due to the brakes.

You already have a friction brake when riding a long board, it's your foot (with a shoe on it)

True, but soft rubber shoe soles aren't exactly the most sustainable replacement for brake lining. Source: I've ruined several pairs of shoes this way.

Yeah, gotta pay to play but skateboarding is fairly cheap as far as hobbies go (if you can stay out of hospital !)

Resistive dissipation like trains.

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