Complete Stop Downhill/Uphill on a Mountainboard (VESC6) is it possible?

That’s why you limit the reverse speed under profiles. So that it doesn’t go back at high speed. A lot of us are using it.

There are 2 types of braking possible when near 0 speed. Active and passive. Passive just shorts all three phases, active pushes current in opposite direction.

But shouldn’t it stop the motor in current mode first and not directly jump from Forward to Reverse with only hitting the reverse once ???

No. It will go into reverse directly after it has braked, but barely because of the reverse speed limit. So the effect is that it brakes, and crawls back in reverse direction if you don’t reduce the brake. If you reduce the brake a little bit, you don’t go back at all.

Strange… I always thought that hitting the brake two times makes it go reverse… (or maybe that was Ackmaniacs Firmware that I have on my longboard?).

Anyways - I will try both modes tomorrow and see which one suits better for everyday use… Thanks for the recommendations

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Yep I have been using it but was an idea of @Winfly or @mishrasubhransu. It’s called active braking. Once you get the right values for your setup and style or works pretty good

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Keep us posted please. I wouldn’t mind being able to hold a stop and have reverse :heart_eyes:

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I had observed that on my robots first, that deceleration close to 0 speed was significantly more if I just used the current mode. Noticed that the motor current were higher. Makes sense because the backemf is very small at low velocities hence the braking current is also pretty small. However in current mode it can apply much larger voltage in opposite direction giving it higher braking current.

Decided to implement on eLofty and Bam it worked really well. But of course it goes back in opposite direction after coming to rest or limiting the reverse speed was very important.

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So I just did a quick test.

With CURRENT Mode:

I will go downhill - brake and the wheels will lock shortly and then instantly go into reverse (not to my liking)

With CURRENT HYST Mode:

I will go downhill - brake - the board will slow down but still roll a little bit - I hit the brake again and then it wil stand still (or go reverse depending on the amount of brake I apply).

So the normal Current mode that will go reverse directly just doesn’t feel right in most situations for me

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Yes, that’s why it is very very important that you restrict the reverse speed to a crawl. Have you done that? You can do that under profiles in the vesc_tool app.

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Yes I did that… Set to 4km/h like recommended earlier…

Set it to something even smaller, say 1km/hr. So you don’t feel imbalanced. The moment you stop you can ease off the brakes a little bit(just the right amount) so that you can stay on the incline.

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@mishrasubhransu

The problem is that the speed limit will not kick in instantly… First the motor will spin up faster until it will get limited down - thats at least what I observed for both forward and reverse speed limitations.

But I will try a lower limit again later today

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hmm, maybe you are right. The way I brake is, my throttle is in strong braking position when I start to brake but ease off as the speed goes to zero. When it’s close to zero I am applying just enough braking to hold me in place. I guess it’s something your brain learns.

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Yes for sure - I will go with the Double Tap Method for now it just feels “safer”.
I tried 1km/h now but the motors are weird jumpy and make noise - with 2 km/h reverse they are also a little bit jumpy but not so much.

Have to test it further on a trail later which speed is the best

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Yeah, jumpy was the reason, I suggested 4km/hr :smiley:

I guess it’s all about personal preference. In double tap you are essentially doing the same thing, just a tiny bit different.

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Well yes and no.

With double tap I can safely pull the brake fully for as long as I want without worrying of going backwards and then when I feel the urge I need that “extra bit” of braking power I just softly hit it again.

When going down and I have to do a fast impulse stop it’s just safer as I don’t have to do complicated mathematical calculations on how to properly dose the brake
grafik

  • I just pull it all the way - which helps in emergency situations (at least for me).
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Hahaha. When you put it that way.

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Level matched with Builder’s Forum. Welcome!

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You guys probably ride on completely different terrain too.
I haven’t tried the reverse with hysteresis since it was just introduced but I am very interested in your results.
Uphill is not a problem but downhill has always found me searching for branches to grab or jumping to turn the board 90 degrees to completely stop on a steep hill.

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I will hopefully have time to test it properly today (if the rain stops).
I will try different modes - different minimum speeds and different terrains / situations

For science

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