10% is a modest/minimal change in my experience. I would play with +25% or higher and you will really start to feel it.
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I never really played with throttle expo. Does it actually make your board accelerate faster or just make it “feel” faster like one of those silly throttle controllers people put in cars.
It robs backend to give you more frontend, or vice versa LOL
Increasing throttle expo on a high power board will have a noticeable impact on how power is delivered. You will feel way more “kick” and it will change how “powerful” your board feels for sure.
In my experience, increasing expo on an underpowered board (10s, 50a per side) can make it more fun and peppy to ride.
It can make a more powerful (18s, 80a per side) feel extremely spicy. It increases the amount of current delivered with the same amount of trigger throw, so it can almost buck you off the board if you go too high.
Yeah that doesn’t really interest me then. I only want full power at full throttle and would prefer the trigger as precise as it can be.
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I believe the issue is more like a throttle ramp time, which throttle curve can help mask but isn’t actually addressing the problem.
It’s raining every day in Melbourne at the moment but once it stops I’ll do some FOC tuning and report back.
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Do you have a Dragy or something similar? Could measure 0-30mph times and see which setup accelerates faster
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Yeah got a racebox mini. I was thinking the same
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Ok finally got a chance to do some more testing. Unfortunately not a lot before my bluetooth module died.
I beat my record at the Radium test track though.
At first I was not having a good time with FOC, feeling very disconnected from the board. So I switched to BLDC mode and immediately felt way more confident with the more responsive throttle and set a great lap time. But then I switched back to FOC and started playing with these two PID settings.
I ended up with 0.006 for both Ki and Kp before the bluetooth module died but would have kept going. The board was feeling awesome and I smashed the track record by 0.6s. FOC is definitely more predictable feeling than BLDC now (however the PID controls effect BLDC as well and I’ve never tried to tune BLDC).
It definitely feels like more tuning could be done but definitely have a go playing with those two. From my reading about PID loops, probably don’t touch the Kd setting…
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What do those settings actually do?
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Thanks for digging and reporting back.
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I’ve been out of touch with things for a while, but people also used to say that BLDC ran cooler. Does anybody know of that is still the consensus?
From my understanding BLDC should keep the controller cooler due to lower switching frequency most of the time, but FOC should keep the motor cooler due to more efficient power delivery
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Yes please someone explain. I really want to get deeper into tuning vesc!
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So I got sent some info by @jaykup to help in my 100d2 tuning and finally got around to doing research on it. Based on the info he got me from the vesc discord and what the general internet showed me. I think this explanation makes pretty good sense for those 2 values
Speed kip pd
Proportional term: this controls how quickly to turn the steering when the heading is not at the set value.
• A low P will lead to sluggish steering, reacting only slowly to set heading changes. It may never reach the commanded value.
• A higher P will give a snappier response, ideally with the steering turning rapidly and smoothly to follow commanded heading changes.
• Too high a P is an important case. If off course by a small amount to the left, a large right turn command will be issued. The turn rate will still be high when it’s back on course, so it will overshoot. Too much P will give steering that weaves alternately left and right, overshooting the required heading; though it may eventually settle if the commanded course remains straight.
• An even higher P will lead to exaggerated oscillations and possibly shaking/vibration depending on the dynamics of the system, how heavy it is, how flexible the tyres and carpet are…
Speed Pid ki
Integral term: this adds more steering action if the error persists for too long.
• If the existing P+D control terms lead to an overall response that settles short of the required heading, an I term will slowly add a steering command to edge closer (we hope).
• Too much Integral action can again cause overshoot/weaving, as the added Integral action turns in the correct way to get onto the commanded heading, but continues to steer because the large I term effectively has a long memory of steering in that direction… it will take a while for the integrated error to reduce and straighten up again.
So in short I guess proportional can be how quick to response/ react . And intergral is how much of a change to correct it.
Also not an expert 
so take what you will. I’m playing with it right now to prevent over current issues and to get more out of my 100d2 before I swap to maker x
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I found this to be a decent intro on PID.
and I’m assuming from your post and other stuff that “speed PID” settings in vesc when in current control mode mean the controlled variable is the target current. but i’m unsure if that’s right. given “speed” in the name.
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