Board feels trotter-y on drops, v6 float package

I’m running v6 float package and on curb drops if I don’t land directly over the tire, the board trotters and it sketches me out. Right now I can’t accelerate into a drop, or do that little nose push thing on slow drops to clear the tail because the nose will dip. What setting should i mess with to fix it?

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Definitely experiment with Rate P! This accelerates the board based on the nose’s angular velocity, rather than the angle itself. It allows those quick pushes you’re thinking of, as well as dampens harsh teetering movements. The default value of 0.6 really should be solid for this purpose, but I’ve experimented with values like 0.8, 0.9, and even a bit higher, though higher can start experiencing negative side effects.

If you’ve changed things beyond default, including an XML of your current settings really helps for questions like this.

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You called it. Increased Rate P from 6 to 7.5 and decreased Angle P from 20 to 19. That was able to fixe 80% of the issues. Will continue to experiment with PID to get it dialed!
I think most of my tuning are still on default values, except for mahony kp 2.3 (from 2.0) and booster is 8, 4, 40, field weakening 30, 65, 500, 2
My specs is stock XR battery no BMS
For reference I’m 200lbs, maybe that has something to do with the board needing more Rate P on drops?

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ok on curb drops it feels mostly ok, as long as I land reasonably balanced (still not as stable as my FM boards but good enough).
But on repeated drops like stairs that last little bit of sketchy-ness really adds up. There is a flight of stairs, like a series of small drops (8x 7cm drop every 1.5m ish), that’s throwing me. On my current vesc tuning it just nose dips and taildrags like crazy. I’m running 1/4in lower tfl center steez on my vesc but I can’t imagine clearance or skill being the issue since I was able to clear it on my 1/2in lowered GT consistently and easily. On GT I just lean forward heavily on repeated drops and the board handles the rest with minimal tail drag.
I experimented with PID and Filter but couldn’t get the desired results. I’ve attached my app and motor config.
vesc_appconf.xml (11.8 KB)
vesc_mcconf.xml (10.4 KB)

Can you include your Float Package XML? Your app and motor configs don’t tell us much.

oh sorry, here!
vesc_floatconf.xml (3.5 KB)

I don’t think this is the primary issue, but if you’re concerned with tail drags, I probably wouldn’t use Brake Tilt. Maybe leave the strength at 0 for now, unless you really need it to get the ride feel you need.

For your IMU settings, there’s a few things. First, I noticed one of your Gyro offsets is very extreme, which seems odd. I would go to the IMU Wizard and do the Gyro calibration step. Make sure they all stabilize before saving. If you were already perfectly calibrated, these should all read near 0 for the offsets before you save, but I have a feeling this is not the case.

Other things I would try is maybe giving Accelerometer Z Low Pass Filter of 1Hz instead of 2Hz a shot. I haven’t had too much of a chance to test myself, but I’ve heard it actually works pretty well and delivers better results without negative side effects so far. I also have an Accelerometer Confidence Decay of 0.02 instead of 0.01, though I don’t think this would make any noticeable difference.

Last thing I would consider is calibrating the Accelerometer, which you haven’t done. Most IMU’s don’t need it to perform well, but it’s definitely worth doing if you’re getting weird behavior, as it could cause the kind of drifting you are describing. You can do so either manually (https://youtu.be/XacXjwFKKF8?t=347), or using the Accelerometer section of the IMU Wizard, which is basically an assisted version of the same process so that you don’t have to look at graphs. Wish I had a good video showing how this is done, but unfortunately I do not yet.

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It’s definitely better now after trying out the settings you suggested, but the nose still dips a little when I accelerate into a drop, and when I land I have to intentionally press the tail down to prevent the nose from hitting the ground. Also maybe this is a related issue but when I do a regular to fakie front side revert on my vesc, I have to put a lot of weight on the battery side of the board, where in FM boards more weight should always be put on the controller side. If I revert the way I do it on a FM board, the vesc will nosedive as I revert. Regular to fakie reverts have always thrown me off when switching back n forth between my vesc and my FM boards. Maybe this is a tuning issue related to the nose dips on drops?

Example of nose dip on drops (0:21): Riding my VESC in NYC (w/ commentary) - YouTube

Can you take a look at my settings again plz. Here are the key updates:

  • Calibrated my gyro and accelerometer to the best of my abilities
  • Tried both 1Hz and 2Hz for Accelerometer Z Low Pass Filter but I can’t really tell that big of a difference.
  • calibrated orientation to level out my w rails
  • tried turning off brake tilt but I really don’t like how it rides. can’t press tail down for nudges and bonks
  • found out that my motor crunch was caused by Motor/FOC/General/Motor Inductance(L) being out of reasonable range from my calibration. still have a bit of crunch on extreme braking on w rails but it’s better now

Thank you for your help!!! Generally I’ve been loving my vesc and have been posting yt videos on it now.

vesc_appconf.xml (11.8 KB)
vesc_floatpkgconf.xml (3.5 KB)
vesc_mcconf.xml (10.4 KB)