Brian,
Some great info here from you! I read the manual last night before I did my upgrade, and still have a few questions. I need to go on the Dynon forum to see if there are further explanations for the adjustments, but hope I can ask a few here since you're just out of beta-land. I will spend some good time testing and tweaking mine as well (when it gets back from CO), but thought I'd try to leverage your recent experience (I know I won't be alone in that desire!
)
I see you've dropped the Tq of the SV-42, then gone up on the pitch gain. Is that opposite adjustments? I know you may not need all the Tq from the bigger servo, but wondering if the two adjustments are similar...perhaps P gain is micro Tq? Or is P Gain an error tolerance adjustment for how far off alt before a correction is made
in level flight.
I went with the SV-42 because some people reported that the SV-32 was not strong enough for an RV7. I have found that the SV-42 is plenty strong at 60% of its rating which is less than a SV-32 at 100% torque so I don't know what to think of that.....If I were doing it again, I would just go with the SV-32.
The torque setting is just that...How much torque are you gonna allow the servo to produce. I set mine by feel of how much force I was comfortable with to cause the servo to slip if I wanted to override the servo with the stick. If you set it too low, the servo will slip all the time causing it to appear mushy and unable to control the airplane very well. If you set it too high, it will be harder to override it if you wanted to.
Pitch gain is a different creature but all of these things interact with each other to some degree. Sensitivity is the overall gain of the system. Pitch gain helps the system settle on an altitude instead of yo-yoing around an altitude.
ALT GAIN also seems to be an error tolerance setting. but this time
for level offs. Is that how you see it?
Yep, it allows you to tweak the approach the system takes to settling on the setpoint. To agressive and it will overshoot, not and it will take forever to get there. It has a smoothing effect on how it gets there.
VSI GAIN seems similar, though the adjustments are opposite (whether to INC or DEC for overshoots or early levels). Did you get more detail on these adjustments?
Similar to the ALT gain just using a different sensor to help you get to the same result.
Pull Rate makes sense...that's been one of my dislikes at times, so this may be a very nice tool!
It is nice..It allows you to tweak your ride...
The two G Error adjustments confused me a bit. For gain, still trying to figure out the difference between "vertical speed changes are not smoothed enough" and "ride is too harsh", which call for opposite adjustments. Do you have a "dumb pilot Bob" way of describing that adjustment?
Pull Rate is the RATE at which it will try and correct and G Error gain is equal of sensitivity for trying to correct the error.
The last one G Error G limit, seems self explanatory as well, and appears to be the cousin of pull rate.
Yep, just sets the limit on how hard the AP will pull when it needs to quickly correct for some disturbance. (Wing removal prevention device) It puts a cap on PULL RATE and G error Gain.
I noticed you adjusted the first two and left the others alone, and that the manual says to adjust them top-down, and stop moving down when you are happy (paraphrase). Did you find that the AP pitch mode was vastly (or nicely) improved out of the box on the default settings, and those minor tweaks were all it took to make you smile big?
Yes, the defaults produced a much better ride than normal. I was smiling before I ever changed anything. The tweaks I made made it that much more better....I would start with the defaults and follow the rules listed to tweak yours in. My guess is all airplanes will have slightly different numbers in the end due to the variables and the taste of the pilot.
In other words, did just adding the new adjustments and using the defaults found in beta testing make for a large leap in pitch performance?
Yes they did! I don't know for sure but I suspect that Dynon rewrote their entire Pitch control algorithm. I don't think they just gave us access to new parameters, I doubt their original algorithms were as sophisticated as they are now. This is just my guess and I have no idea what Dynon did internally so take this comment as a grain of salt...
I figure you played with all the settings along the beta trail...did the lower ones have smaller effects than upper settings, or did they have a more dramatic impact, and are better left alone unless really necessary?
Follow their directions in order to make the tweaking go faster. Work from the top down... All of these things tend to interact with each other and it will take you some time to understand how each parameter "feels" in real life. I had no reason to mess with the last four cuz they worked fine for me at the defaults. No reason you can't experiment with em though. Just be carefull with the G Error Limit. Most likely the servo would slip before damage was done but you need to be carefull with that one.
I know that's a lot of questions (probably over-anal-yzing), and much may be answered when I fly it, but I appreciate any illumination/clarification you may have from your test experience. If there is a Dynon discussion that adds detail to the manual, please do point me (us) there.
I am sure there will be more public talk as people explore this new capability. The Alpha and Beta versions worked so well out of the box that there is not much additional to add that you have not already seen. Most of the tweaks by Dynon were minor fixes Alpha to Release.
Thanks for sharing your numbers and your experience! You da man!!
Cheers,
Bob