Hi everyone, im planning on building an electric longboard with HUB motors for a school project. The school requires the board to have a speed limit of 15km/h and I have no idea how I am going to add a speed limit on this. But I also want to be able to take this off in the future so I dont want it to be permanent.
If using vesc you can just limit the Throttle
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is this only for certain ESC’s or can I do it for all?
VESC ( Vedder Electric Speed Controller) Only vesc and maybe a Arc 200
If you’re going to use an ESC rather than a quality vesc you could go lipos and configure in 6s and then reconfigure later for 10s or 12s
VESC has inbuilt ways of limiting the max speed in an elegant way. Either change the erpm limit or use profiles
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Be careful with erpm limits on the VESC before I had one of my boards set to go 15mph max and was riding around with my friend. He was accelerating (and leaning forward to compensate) and he hit the speed limit and it cut power to prevent him going faster causing him to go off the board. (He ended up being fine with just a couple scratches to show) for me personally this is the reason I will never limit the speed with erpm again
For me the ERPM cut is pretty smooth, just be sure to disable the use of brake to limit the speed, that’s what makes things go bad
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I’m pretty sure that setting was off but I can’t say for sure. Anyway to me it’s still not preferable because I would rather use lower kv and gearing to reduce the speed to your target speed so that you get the max torque and speed out of your board. (Although in @CookyMellow 's case since the target speed is very low erpm limit makes sense)
It’s a good idea to test a max eprm limit setting on the bench first. If it works well it should come to a smooth limit at the top end. If the brake to limit speed feature is enabled it will oscillate at max speed. Bap Bap Bap kind of thing. Though I think this brake feature was removed from newer version of vesc tool. So should not cause an issue for anyone now.
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Hub motors suck. Do yourself a favor and use belts. Later you can remove the speed limit in software after the project is over.
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School project.
I disagree entirely for this reason. Hub motors are dead simple to get up and running, building a belt drive needlessly overcomplicates this when it’s clearly not aimed at performance
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Hub motors will make this a pile of trash later — whereas if it’s built properly, it can be turned into something awesome.
Also this, you could remove one side and run single motor.
But keep the other parts for later.
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Actually no, building with budget parts will do that regardless.
What you’re suggesting vastly increases the technical difficulty of this project to someone starting out.
Not everyone is feeding a family of 9 via ESK8, Brian.
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Hmm I don’t know but it was older. this incident happened about a year ago and the VESC was setup with the bldc tool so it’s possible that it was me accidentally checking the limit erpm with negative torque box.
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build the board as fast as you want with whatever components you want then use a cheap rc controller/transmitter that has adjustable throttle end points. Set end points to achieve your limited speed.
That would only add a power limit and not a speed limit.
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without knowing the components used, the objective of the build, op’s skill level or budget or anything else… limiting the throttle on the transmitter is the simplest/fool proof way to limit speed.
The simplest way to limit speed is to remove the wheels. There are better ways though. Limiting the throttle will only limit the power and not the speed.
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The main reason I want HUB motors was because I like being able to push it around aswell, rather than just purely using the motor. @b264
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