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Allow braking to override negative ramping time

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Paul15578
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Allow braking to override negative ramping time

Hi Benjamin

REQUEST: 
Could you please allow braking override the negative ramping time so that it can be safely used?

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Reason/Background
Currently you have to wait for the down ramping time to finish before the any braking can be/is applied.

I was hoping to use a long negative ramping, so as to reduce the jerk felt when releasing the trigger to neutral while under load
ie going up slight incline with moderate current applied then releasing throttle to neutral causes a jerking action with low negaitve ramping ie 0.3s

and also use it as a way to simulate a longer free roll sensation when deliberately letting going to throttle neutral (and not applying brake) maybe 10s setting

I didnt realise the brakes wouldnt work during down ramping
So i tested it out today and had to jump off the board as it shot off ramping down for my 10 second setting. The brakes didnt stop the board during this 10 seconds as it flew off and did a few flips into the bush and they wheels kept spinning until the 10 seconds was up

Regards

Paul
(Using Nunchuk)

 

JL2579
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Joined: 2017-12-25 21:09
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This is actually a serious issue.

If it is not fixed immediately, I would at least put a warning and or limit the ramp down time to 1 second for now. Do you have seperate control imputs for acceleration and breaking atm?

As a workaround I suggest to try a different control method, and see if it works better for you.

JL2579

Paul15578
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Hi JL,
It could be the most dangerous setting in the VESCTOOL!
Yeah i have it limited to 1 second for now, 
When you say separate control inputs what do you mean? Using nunchuk, the pot one way is accel, the other way is brake. But pushing into brake does nothing until the full ramping down is complete, So it you go full speed, it will gradually ramp down and take 10 seconds (if 10 sec setting on negative ramping) to effectively be in throttle neutral and there is no way to get it there without waiting.

Paul

Pedrodemio
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Any update on this Benjamin or Frank? I'm using really reduced ramping times because of that

benjamin
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Joined: 2016-12-26 15:20
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This is actually the intended behavior. Your use case is not what I had in mind with the function, as I always wanted it to release the throttle much faster then when applying throttle (hence the default default value). It does make some sense to use it that way though, it might actually be quite nice. I will see what I can do. Most likely I will make it so that the fastest ramping time is dominant when the throttle is not in the neutral position.

benjamin
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I changed the behavior in the upcoming firmware such that the downramp time is used when the throttle is in the neutral position, and the shortest of the two times is used when it is not in neutral, and the absolute value is decreasing.