Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 It's my understanding that feed forward is a reaction to your stick movements. However I'm not 100% sure how that translates in the real world.
So the way I had it described (i think) is that the faster you move your stick the more the quad will respond to that movement. But what does that mean? Does feed forward some how reduce latency? I've heard technical explanations explain that this is the case, and it makes sense, however it doesn't seem right to me that such a small delay (the time it takes the pid controller to read the set point basically) could possibly be felt by the user can it? I might just have it all wrong.
And say I do a full stick deflection as fast as I can, it's not like FF will increase my rates right? I'm still gonna spin at the same rate no? Say I do a full stick deflection at half the speed of as fast as I can... how then does the FF affect THAT?
I guess the easiest questions I can ask are "Does FF reduce actual latency"? And/or "Does FF actually increase the rate of my spin when I deflect fast as appose to semi fast"
See my questions don't even really make sense because I struggle to understand what is going on. I get that it helps avoid reading the PID errors in order to follow the set point more accurately, But I can't figure out what that means in practical terms and if there should be any noticeable difference when flying other than a smoother flight. IDk I proly sound like an idiot right now so I'm gonna just leave it there and see if anyone understands what it is I'm trying to figure out, because i'm not even sure I do. 'Ignore' is the route word of Ignorant.
![[-]](https://intofpv.com/images/collapse.png) • Posts: 761 Threads: 66 Likes Received: 352 in 254 posts Likes Given: 490 Joined: May 2019 Reputation: 12  its like a new language. This is my go to start site for pretty much all questions. https://oscarliang.com/ What you are talking about is called throttle curve https://oscarliang.com/throttle-curve/ • Posts: 6,112 Threads: 172 Likes Received: 2,286 in 1,833 posts Likes Given: 4,736 Joined: Feb 2019 Reputation: 100 28-Aug-2019, 01:13 PM (This post was last modified: 28-Aug-2019, 01:15 PM by hugnosed_bat.) https://oscarliang.com/setpoint-weight-t...asurement/ (i struggle with technical understanding, but :-) i use it like a rate feater, smoothing inputs. i would suggest just try an exessive low and as example high value up to 180... try different stickmovements speeds... )
answer at the same time :-) • Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 (28-Aug-2019, 01:13 PM)hugnosed_bat Wrote: https://oscarliang.com/setpoint-weight-t...asurement/
(i struggle with technical understanding, but :-) i use it like a rate feater, smoothing inputs. i would suggest just try an exessive low and as example high value up to 180... try different stickmovements speeds... )
answer at the same time :-) Yes I think just trying FF really low then really high and seeing what difference i feel is what I should do. FF has no relationship to D term I do know that. I know it's set point transition like... 'remodeled' or w.e but before setpoint transition had some sort of relationship with D-term and FF does not. Still though, can adding a very high FF value hurt anything? Hot motors etc? And if I looked at a black box i can kinda understand what it's doing there more than what it's doing in a real world sense.... mostly because the only videos about what it does are very technical and ONLY SHOW what it does in the black box and in a technical sense. When you say smoother would "more loose" be a better description than "smoother" or no? Because I can kinda wrap my head around it if that were the case I guess... less 'responsive' more 'loose' feeling. Gargh so many of these things have such similar properties it all gets jumbled xD I love the technical side of this hobby though, i really want to understand it. I spent like 8 hours one day tuning my quad based on videos I watched and black box readings and at the first hour my quads gyro and set point were way off and the gyro was very noisy and jagged, at the end of the 8th hour my set point and gyro were basically exactly together and there was barely any noise on any axis but the roll (I think that had to do with the fact I used a stretched x frame and it was a 3 inch quad). It was VERY satisfying to get the black box readings to have basically no noise and still have cool motors and have everything line up extremely well. I'm good at copying things though, so if you asked me to do it again without any reference I'd be lost most likely xD I'm very good at drawing things. I can draw just about anyhting in extreme detail, however, if you were to ask me to draw something from my head without COPYING by looking at something and drawing it, I'd give you a paper with a stick figure on it  'Ignore' is the route word of Ignorant.
Posts: 12,099 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 Let me see if I can explain in analogy. Let's say you are driving a car straight and you want to make a turn. With low FF, you will turn smoothly as if you had traction control. Whereas high FF, you will whip you into the turn. You rates, you can think of how sensitive you steering wheel is. Your rates also limits how aggressive that whip will be. • Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 (28-Aug-2019, 05:12 PM)voodoo614 Wrote: Let me see if I can explain in analogy. Let's say you are driving a car straight and you want to make a turn. With low FF, you will turn smoothly as if you had traction control. Whereas high FF, you will whip you into the turn. You rates, you can think of how sensitive you steering wheel is. Your rates also limits how aggressive that whip will be. How about if I used this as an analogy does this work? More FF = steering a car without power steering even though the turning take is the same. less FF = power steering with steering rate being the same. I'm gonna go fly today I might try some different FF levels. Problem is I only have 2 batteries so it's hard to really have fun and test shit at the same time. 'Ignore' is the route word of Ignorant.
• Posts: 12,099 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 (29-Aug-2019, 07:52 PM)bLoWsMokE Wrote: How about if I used this as an analogy does this work?
More FF = steering a car without power steering even though the turning take is the same.
less FF = power steering with steering rate being the same.
I'm gonna go fly today I might try some different FF levels. Problem is I only have 2 batteries so it's hard to really have fun and test shit at the same time. Not quite the correct analog. It is more like the power steering is the same. If you do the same quick turn of the steering wheel, high FF will whip you into the turn. While low FF slowly turn you. But definitely try different FF. • Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 (29-Aug-2019, 11:39 PM)voodoo614 Wrote: Not quite the correct analog. It is more like the power steering is the same. If you do the same quick turn of the steering wheel, high FF will whip you into the turn. While low FF slowly turn you.
But definitely try different FF. Thanks I will... eventually. I'm pretty happy with how it's flying though, and I can only really change it with my computer and I never fly near home. 'Ignore' is the route word of Ignorant.
• Posts: 1,312 Threads: 50 Likes Received: 832 in 504 posts Likes Given: 372 Joined: Jul 2018 Reputation: 51 You can actually mess with your PIDs (including feed-forward) using the Betaflight OSD, which is definitely the easiest way to do it in the field. As always, Oscar has an article: https://oscarliang.com/betaflight-osd/ Scroll down to the bit about the Betaflight OSD menu for the part that might help.
The ground is for dead people. Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 (01-Sep-2019, 10:18 PM)Banelle Wrote: You can actually mess with your PIDs (including feed-forward) using the Betaflight OSD, which is definitely the easiest way to do it in the field.
As always, Oscar has an article:
https://oscarliang.com/betaflight-osd/
Scroll down to the bit about the Betaflight OSD menu for the part that might help. I only fly LOS. A. because LOS is the shiz B. because i can't afford goggles. 'Ignore' is the route word of Ignorant.
• Posts: 12,099 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 (02-Sep-2019, 04:45 AM)bLoWsMokE Wrote: I only fly LOS.
A. because LOS is the shiz
B. because i can't afford goggles. I give you props for flying LOS. I sucks at LOS. • Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 (02-Sep-2019, 05:31 AM)voodoo614 Wrote: I give you props for flying LOS. I sucks at LOS. I wanna take videos but it's impossible. I can't figure out a way to strat my phone to my head xD And no matter what i do I can't get the drone in picture for very long when the phone is stationary recording so I do wish I had goggles so I can record as well. I wish I had goggles for many other reasons, but that is just another..... *sigh* 'Ignore' is the route word of Ignorant.
• Posts: 12,099 Threads: 125 Likes Received: 3,739 in 2,836 posts Likes Given: 99 Joined: Feb 2017 Reputation: 388 Maybe something like this. If you use a GoPro, then there are quite a few products for head strap. Cellfy Universal Head Mount for your Smartphone https://www.amazon.com/dp/B00J6KO9O8/ref...BDbGSAQBJJ • Posts: 1,798 Threads: 57 Likes Received: 254 in 227 posts Likes Given: 102 Joined: Aug 2019 Reputation: 12 02-Sep-2019, 01:16 PM (This post was last modified: 02-Sep-2019, 01:21 PM by bLoWsMokE.) (02-Sep-2019, 10:50 AM)voodoo614 Wrote: Maybe something like this. If you use a GoPro, then there are quite a few products for head strap.
Cellfy Universal Head Mount for your Smartphone https://www.amazon.com/dp/B00J6KO9O8/ref...BDbGSAQBJJ HA! If I could afford a gopro I'd get goggles first  Thanks for that link that looks pretty cool. Unfortunately I don't have a mustache so I don't think this will work for me. I think I'd rather save up for goggles though. I have a universal cell phone mount I got with a toy drone that attaches to its' TX, I'm just trying to figure a way to strap that to my head, it's very uncomfortable. Like un-useably so. ie. it F**kin hurts! <<AHHH I caught myself there, had to rewrite it with the *'s xD 'Ignore' is the route word of Ignorant.
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