The modes feature used by the METR Pro and Ackmaniac firmware allow you to control the absolute top speed. Is that what you are looking for?
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it takes much less current to sustain constant reasonable speed than is used during typical acceleration, so limiting speed in this way would limit your acceleration dramatically. and forget about hill climbing. the best way would be to limit the duty cycle to less than 95% in current control mode, in my opinion. limiting duty cycle to 50% is equivalent to changing the battery voltage from 12S to 6S, from the motor’s perspective, without sacrificing torque during acceleration, and without increasing the battery current required for that torque.
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this shows the effects of changing the duty cycle limit from 95% to 50%, without changing any of the other settings or hardware:
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VESC can’t act like a Evolve ESC no matter what remote or throttle curve you use. Have to either get used to it or try something different.
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Yeah that’s what I suspected. Thanks
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I finally got a good answer over at the vedder forum…
@Chricious if you are using a dual controller it’s possible your 120a bat setting limits each motor to 60a bat…
if that’s the case, then changing the bat setting to 200a and leaving the motor setting at 100a, would give you 100a bat and 100a motor per motor, which in theory would enable you to retain all your torque and have full throttle range and torque at the higher speeds.
if the bat setting you referred to is “per motor,” then it depends on what the following firmware limits are that the hardware developer chose in your particular firmware for your controller…
^CURRENT_IN would refer to the firmware battery current limit for your hardware
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& @murdomeek @mmaner @BluPenguin its possible changing this value could limit the duty cycle and max motor rpm to a chosen percentage of the battery voltage * kv:
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It doesn’t matter what we do, we can’t achieve a proportional throttle to speed ratio in current control mode, like it is in duty cycle mode or on other e-boards on the market. We need to reprogram something, or maybe get a pre programmed RC or waiting for a Vedder update. I’m really wondering why this is not bothering anybody else.
throttle in current control doesn’t control speed it controls torque.
suppose you are at constant speed on flat ground at constant throttle in current control and you start going up hill, you will slow down… more throttle/torque is required.
duty mode doesn’t control speed it controls the percentage of time current is drawn from the battery
it sounds like you want the throttle to set cruise control speed with some kind of limited current ramping
the dead travel in the throttle is what I was trying to help you fix not turning current/torque control into speed/cruise control… neither current nor duty control will achieve what you want
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when i’m in my car on the highway in cruise control (constant speed regardless of incline), sometimes i adjust my speed by using the up and down arrows on the cruise control, rather than using the gas pedal. it sounds like you want adjusting the position of the throttle to be equivalent to using the up and down arrows on a car’s cruise control… is that correct?
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As said above, you can set profiles in metr with Max speed limits. Honestly though I’ve never thought that I want remote position to correlate to speed. What makes the board predictable is knowing that XX% throttle = XX motor power to the ground.
In order for the throttle position to control % of max speed rather than torque, the board will need to apply regen braking for you automatically on a downhill… and if you suddenly let go of the throttle do you want the wheels to lock up?
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how would this work for myself (100kg or more) and my buddy (50kg) who uses my boards too?
Why would this bother me?
Once I reach my desired speed let’s say with max acceleration, I just dial back on my trigger to the point where it will maintain that speed.
Then I’ll carve the way I want to and sometimes I’ll adjust the trigger in case I want some extra power coming out of a carve.
I don’t see what you are trying to solve.
If you want to carve at a set speed that maintains that speed, you will need cruise control which will do just that.
Anything else, no matter what mode, will always require input adjustment from the trigger to maintain a certain speed.
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Duty cycle mode was behaving exactly like the Evolve RC and that’s what I want. No dead end on the throttle and no accelerating after reaching the given percentage of speed.
that’s not what I want and I explained it now like 6 times in 2 different threats. If you don’t know how a “normal” RC behaves please check it first. I posted also a video of the Evolve RC and how it works. Please don’t get me wrong. I’m thankful for your engagement, but it gets difficult to explain over and over what’s wanted. I think the other guys here got it already.
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so when duty mode is giving you the performance you want, what are the regen brake settings? (motor min and battery min). I think if these numbers are as high as you can safely do in current control mode, when you let go of the throttle I think you’ll get strong braking without applying the brakes.
also in duty mode, you aren’t actually directly controlling the duty, because during acceleration the duty cycle will be adjusted based on the current limits, so any time you’re changing speed, you’re actually in current control with current ramping not controlling duty, even though at constant speed the throttle position might correspond with duty
I don’t know, maybe it’s a question of power. If I pull the trigger off over 10% my board accelerates like crazy to top speed wich is 55km/h at the moment. This is quite hard to adjust, or to cruise. If I want to get to cruising speed I have literally just around 5% of throttle travel which I can use. It’s like juggling with raw eggs.
What does dead end on the throttle mean, and when does that happen?
Let’s say I am on 30% throttle. After let’s say 5sec I am on top speed. Then I still have 70% dead travel on the throttle which doesn’t effect the speed.