LibrePilot Forum

Users => Applications - Autonomous Flight => Topic started by: JustAPilot on May 16, 2017, 12:05:18 am

Title: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 16, 2017, 12:05:18 am
Hi there,
I have noticed the automatic configuration is different than the manual configuration (M8N Gps). The manual configuration can be used with the Revo I suppose? The manual configuration activates 4 messages whereas the automatic one activates only 1 message (which is not one of the 4 of the manual one).
Which one is better(more accurate), auto(with 1 message) or manual(with 4 messages)?
Thanks in advance for your feedback.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 16, 2017, 04:43:19 am
The single and multi message formats are equivalent.  One of the multi messages is a timestamp for the other messages, but there is an ID field in each multi message that allows you to match the several messages into a single chunk of data that was taken at the same time.

CC3D only knows how to understand the multi message format.  Older GPS units only know how to send the multi message format.  The original OP code was written for the multi message format.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 18, 2017, 07:32:00 pm
Hi TheOtherCliff,

Thanks for your feedback.
Maybe it's essential to let users know what the auto config sets, so they know it is set correctly, if they check. I did not expect it to be different than the manual config. I thought my GPS was not remembering the manual settings I saved. But it was the auto config writing a totally different setting than the manual one.
Thanks for your time. I'll be having more questions ;)
Regards,
JAP
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 19, 2017, 01:26:55 am
Revo automatic GPS configuration detects whether the (Ublox) GPS is old style (Neo6- only knows multi message format) or new style (Neo7+ knows both formats).  The default Revo settings tells the GPS to temporarily set it's configuration to either the multi message set or the single message set (depending on GPS version).  FYI: There are other messages even in what I've called the "single message" format here.

So it does not change the GPS's internal configuration permanently.  This means that with one GPS you can fly different firmwares that need different protocols.  Revo sets it to what it needs temporarily on each boot up and so it has it's different, permanent configuration when you boot it when it is attached to different firmware that needs the permanent configuration.

There are other Revo settings, for instance, you can have the Revo change the GPS's configuration and make it permanent in the GPS.  This is helpful if you have a Neo6 GPS that you want to use with CC3D.  Connect it to Revo this way one time and it will work on your CC3D (CC3D doesn't have GPS auto-config) from then on.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 21, 2017, 08:30:14 pm
Wow,..you really know a lot about this and I'm glad I've kept my Revo with LibrePilot. I have two questions. If need to ask these somewhere else please let me know.

1. Is there a way to make the copter fly nose in when in RTB mode? It would be awesome if it flew nose in and when it stops to start descending (ReturnToBaseNextCommand) it rotates and points in the same orientation as when it took off, and then starts descending and lands.

2. When in VelocityRoam mode and I do a bank or pitch and let go of the stick (instead of gently helping the stick to it center position) the copter levels itself too quickly and oscillates 4 to 5 times before it levels, like a crazy bee. It only happens when the stick goes quickly to center. The oscillation is not gentle, it uses quick revs while doing this. When do I need to adjust this? I cannot eliminate it from the general PIDs settings. I only fly in three modes: Attitude, VelocityRoam, RTB.

I'm almost done tuning everything neatly. Thanks in advance for your time and response.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 21, 2017, 10:24:10 pm
I wrote some of the GPS code.  ;)

Sounds like you want it to fly RTB like a DJI/Naza does RTH.  :)

System -> Settings -> VtolPathFollowerSettings
has YawControl, which has these options:
Manual,Tailin,MovementDirection,PathDirection,POI
defaultvalue=Manual

As you can see there is a Tail-In but not a Nose-In.  PathDirection is close to Nose-In though.  And it does not rotate to takeoff heading for landing at all.

You should test these carefully some of them act a bit crazy when the quad is hovering motionless (if you have a fast yaw configured).  For instance, with MovementDirection yaw jumps around randomly when hovering motionless.  The small motions are random this way or that and so it yaws this way or that.  Manual is always safe though.

Oscillations during PH are known to happen with authentic DJI/Naza GPSs.  Most (some?) DJI clones don't have that issue.  If you are using a DJI/Naza GPS I suggest that you try the firmware here and see if that helps.
https://forum.librepilot.org/index.php?topic=3012.msg21154#msg21154
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 22, 2017, 10:27:09 pm
Ah,..so that's why ;)
I will only try the PathDirection one. This means that when I activate RTB (with PathDirection selected) all stick input is disabled? It would be great if I could override the Yaw with stick input while it's moving towards Base and when I let go of the yaw stick, it smoothly rotates back to its PathDirection.

The GPS I have is a uBlox M8N. The problem is not related to the GPS I think. I managed to tame that jerky correction movement by lowering the Responsiveness (Attitude) to 30. The whole time I was tweaking the Rate (Inner loop) PIDs and didn't notice any difference  :-[. I don't fly Rate at all, so I guess I should not tweak anything related to Rate.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 22, 2017, 11:48:12 pm
In waypoint/RTB I recall that yaw is not user controllable except when using the manual yaw option.  You suggest an attitude mode for yaw.  This is easily doable, but would require tuning or at least checking the attitude yaw PID.  I suggest using manual for yaw.  If you can see (FPV) enough to turn and look at something, you can turn it back or just leave it there.  It flies correctly either way.

At one time, zero throttle would stop the motors, but I would test it.  I forget if the current code does this.

Rate mode is inner loop.  Rate mode only uses inner loop.  Attitude mode is outer loop which uses inner loop as well as outer loop.  So if you use Attitude mode, both your inner and outer loops need to be tuned acceptably well.  The easy way to get both inner and outer tuned well (works for most quads but not all) is to use AutoTune.
https://librepilot.atlassian.net/wiki/display/LPDOC/AutoTune
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 23, 2017, 01:22:59 pm
About the inner/outer PID loops. Will this be a good approach to tune both inner and outer manually?
1. fly in rate mode and tune only rate PIDs. When copter flies satisfactory then proceed to step 2.
2. fly in attitude mode and tune only attitude PIDs.
Done. I should have both inner/outer well tuned.

I've tested autotune before and I find it makes the copter too snappy for my (sight seeing) purposes. Maybe I should auto tune it and then tame it to my liking. (it's not a race quad)
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 23, 2017, 08:56:20 pm
You manual tuning method should work OK ... but

AutoTune has a SmoothQuick slider that adjusts PIDs to be smoother or quicker ... but

Many people assume that they should reduce the PIDs in order to slow the response down.  That isn't the correct way to slow response down.  The PIDs should be as high as possible (such as produced by AutoTune) and be adjusted towards smooth only enough to reduce jitter because you want smooth video.

Reducing PIDs just to reduce response makes it handle worse in some ways that you really don't want.  For instance if you descend vertically you need those PIDs high to avoid the problem of instability when falling in your own downwash.

The right way to reduce response it to adjust Responsiveness on the Stabilization page (Basic or Advanced tab).

You should try AutoTune again and reduce Responsiveness on the Stabilization page.  ;)
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 23, 2017, 11:36:29 pm
That's exactly what I thought at the field today. You don't degrade the gas/oxygen mix on the carburetor of car to make it more docile, you adjust how the pedal reacts to the carburetor/fuel injector.
I'll try that autotune again and adjust the responsiveness.

I did try the PathDirection in RTB today. It worked but even though I don't have high Yaw deg/s it starts with an excessive force for a fraction of a second. The actual rotation speed is moderate, this is fine,..but how it starts this turning is with too much force. Scary.  How to tame this transition?
When I am in PH and I switch to RTB, the transition is also a bit too sudden. It's not like a human would do it with the sticks. It's too "binary".

I have the exact same copter+hardware but with Betaflight(Omnibus F4) and ESCs (BLHeli) set to Damped Light. No issues.
The exact same copter but with LibrePilot(16.09 on Revo mini) when I set the ESCs to Damped Light, the motors suddenly start making a scary noise,..as if someone is drilling with a hammer drill. So I have to set the ESCs to Low (instead of damped light). This buzzing/drilling starts randomly while flying, most times during switch to PH. Any hints?

You've been and are being very helpful and I thank you for this.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 24, 2017, 12:32:59 am
I did try the PathDirection in RTB today. It worked but even though I don't have high Yaw deg/s it starts with an excessive force for a fraction of a second. The actual rotation speed is moderate, this is fine,..but how it starts this turning is with too much force. Scary.  How to tame this transition?
When I am in PH and I switch to RTB, the transition is also a bit too sudden. It's not like a human would do it with the sticks. It's too "binary".
I'm going to make a guess as to the most correct way to adjust that.  I think that this is actually running yaw in attitude mode, which is uncommon so there is no place to adjust it in the GUI.  (Assuming you are using bank1) Reduce the System page StabilizationSettingsBank1 -> YawPI -> P.  Cut it in half for a test.

... but with LibrePilot(16.09 on Revo mini) when I set the ESCs to Damped Light, the motors suddenly start making a scary noise,..as if someone is drilling with a hammer drill. So I have to set the ESCs to Low (instead of damped light). This buzzing/drilling starts randomly while flying, most times during switch to PH. Any hints?
I liken the sound to throwing a medium sized stick into the prop at about half power.  :(  Are you using the same ESC protocol in both cases (LP and Betaflight) (say OneShot125)?  Can you test with Output page "Test Outputs" (props off) at full throttle to make sure it can go to full throttle without stuttering?  If OK, I would make a second test with it tied down to a wooden deck with props on (please be very very careful), and also using the Output page.

This is caused by the ESC loosing sync with the motor (especially when the ESC is commanded to change the motor speed a lot in a short time).  This can be caused by props that are too big but more often are caused by old firmware that has this issue.

Bad ESC firmware?  Props too big?  Signal protocol isn't matched well (between ESC and FC)?  Or maybe you have adjusted some uncommon settings in the ESC firmware?  I would start by updating it to the latest ESC firmware, checking prop size, and using stock ESC settings for your selected protocol.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 24, 2017, 08:32:03 pm
About the ESC.. it's an ESC manufactured in end 2016. I have flashed it with the latest BLHeli firmware. Everything is in the latest Released version.

The way I tested both Quads (LibrePilot on Revo and Betaflight on Omnibus F4) is:  By the way my non-FPV quad is a 3D quad with motor reversing.
fasten quad to heavy platform.
put 1 prop on a motor and connect its ESC to servo tester. The ESC has bidirectional activated in BLHeli and motors with bi-directional props.
power up and start turning gently on the servo tester to see if the motor spins up without too much jitter and then I reverse the direction also easy. I repeat this and gradually increasing the amount of power, going both directions and with even faster transitions.
On both quads all motors+escs work perfectly (with servo tester as throttle signal provider). So I'm confident the motor + esc is working flawlessly.
On the Fpv quad I disable bidirectional after testing. 

But on the Omnibus there is no desync. On the fpv quad I have to disable Damped Light otherwise there is this buzzing/drilling sound.

I'm asking myself if LP is pushing to much confusing throttle commands or if the throttle signal/command is different than on Betaflight.
Adjusting timing of motor to try to fix this is masking the rootcause.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 24, 2017, 09:20:16 pm
Latest Update:
I just tested on the bench. Damped Light=ON
Quickly raising the throttle via GSC causes that desync issue.
Using servo Tester and quickly raising the throttle there is No issue, no desync.
In LP the motors are set to onshot125 protocol
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 24, 2017, 09:55:34 pm
servo tester probably has smoothed response

servo tester uses PWM width pulses

it could be related to oneshot125, maybe try pwmsync
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 24, 2017, 10:17:19 pm
I FOUND THE PROBLEM :D :D :D

While testing, Motor1 has no issues. Only Motor2,3,4 have the "sync" issue.
I connect Motor4 to the output of Motor1 and Motor4 now runs fine with No issues.
The difference between output1 and output2,3,4 ? = GROUND
Only output1 has a Ground wire on the MiniREVO. Apparently my Afro30A ESCs do need that ground connection to work as expected. (servo tester has ground)

Sigh,..finally figured this out. Thanks for shouting some directions.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 25, 2017, 05:51:36 pm
The wind was calm today so I tried the AutoTune. The tuning went fine but the results are strange.
Without stick movement, the copter hovers fine. When I move the stick (roll/pitch) the copter oscillates.
When I looked at the stored autotune values in GCS, they are high and even red.  Integral(R,P,Y): 256, 294, 462   (picture attached)

I will use my default mushy settings again. And I will try what you suggested: "StabilizationSettingsBank1 -> YawPI -> P.  Cut it in half for a test"
Hopefully this will remove that aggressive correction when I let go of the stick.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 25, 2017, 07:27:29 pm
Sounds like a bad tune, which does happen sometimes.

If you would post System -> Settings -> SystemIdentSettings
I might be able to tell you what number there looks wrong.

After that, I would run AutoTune again.  :)
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 25, 2017, 10:35:37 pm
I've attached a screenshot of the SystemIdentSettings.  (after the bad tuning I did reset bank3 to defaults)

Please have a look at these two videos?  and listen to the sudden boost at the moment I start moving the stick (roll or pitch or yaw) and also at the moment of centering the stick. I seems like at the moment of transitioning from/to another "subroutine" there is this twitch/boost.
This is in PH+GPSAssist.

youtu.be/rQs-mWN-C3E
youtu.be/cuvGy3NN7-8

The copter loses altitude when I bank. Tips?

Thanks in advance

Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 26, 2017, 07:13:07 am
(Your screen shot) Those are SIS default values.  You must plug in the FC to see the current values.  They are only stored on the FC.  But I don't see a problem that needs fixing in the videos.

Those sudden boosts are perfectly normal.  If all those twitches were caused by transmitter stick movements, I would say that it was flying very well.

Let me give you a yaw example.  Yaw is a "rate control" which means the rotation rate is a simple proportion of where the stick is.  In the center you have 0 degrees rotation per second.  At full stick you may have configured 300 degrees per second.  So at half stick right, you get a right rotation of 150 degrees per second.  What happens if you move the stick from 0 to 150 degrees per second "instantly".  You have commanded it to accelerate from 0 degrees per second to 150 degrees per second instantly so it does the best it can to get it to 150 as quickly as possible.  Once it gets to 150, the motors slow down because it takes much much less force to hold it at 150 rotation rate.

This is just like a car.  You hit "resume" on the cruise control and so you have commanded it to get to 110 quickly, but once you get to that speed, it takes a much smaller amount of power to keep it there.

If you don't like the revving up, you can reduce it, but not eliminate it.  This will make the quad smoother, but slower to react to your commands.  Personally, I like to be able to tell it to do something quickly if I want, and just move the sticks slower if I want it slower.

One way to slow it / smooth it is to reduce "Maximum Rate (all modes)" (I forget the exact name) toward the top of the Stabilization page (bank 1, 2, or 3) Advanced tab.

In GPS (VelocityRoam) mode, the roll and pitch sticks command horizontal speed.  Say that you have set 8 m/s configured as max speed.  Instantly moving the stick to 1/2 stick is asking for it to instantly be moving 4 m/s.  It tries to instantly bank the maximum configured amount in order to accelerate horizontally as quickly as possible.  As it gets to 4 m/s it levels back out to almost level, just enough to maintain 4 m/s.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 26, 2017, 09:16:44 am
The SIS values can't be read via OPLink? I was connected to the fc via OPLink. I am at this moment too to double check and those values are greyed out. (other values are not greyed out).  Maybe this is the problem?

The sudden boosts occur without moving the stick a lot. Even if you extremely slowly move the stick just a tiny little bit, it will do that sudden boost. And also when going back to center extremely slowly with the stick, you have that sudden boost. It does this only when in PH mode.   :'(
In attitude mode this does not happen at all.

Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 26, 2017, 10:52:15 am
Ahh yes, SIS doesn't show up if AutoTune module is disabled.  AT module gets enabled if you have AT on your FM switch or if you manually enable it in System->Settings->HWSettings->OptionalModules

Quote
The sudden boosts occur without moving the stick a lot. Even if you extremely slowly move the stick just a tiny little bit, it will do that sudden boost. And also when going back to center extremely slowly with the stick, you have that sudden boost. It does this only when in PH mode.   :'(
In attitude mode this does not happen at all.
Does full yaw make it spin very fast (top speed, not acceleration)?  How fast would you guess?  If so, reduce the Stabilization->Advanced->bank1.2.3->MaxRateLimit(and RateMode)->Yaw

For yaw, one difference may be that in Attitude mode, the yaw is actually in Rate mode, but in PH/VR it is Attitude mode (I haven't looked at that code to verify).  If that is the case then reducing System->Settings->StabilizationBank1,2,3   YawPI->Kp  or  YawMax might help.

Because of the way it works, yaw control is fairly ineffective, so it takes a lot of motor RPM change to make a small amount of yaw force.  To make a yaw, it say reduces the NW and SE motors and increases the NE and SW motors by a fairly large amount.

Again, to me those videos looked like good examples of a GPS quad working well.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 26, 2017, 11:04:03 am
I just noticed that you wrote PH+GPSAssist.

I didn't think that would even allow you to arm that way.  You shouldn't use GPSAssist with any GPS mode.  GPSAssist is meant to give you a temporary PH when you release the sticks when you are flying a non-GPS mode.

Maybe you meant AH AltitudeHold.  In that case let me suggest you use AltitudeVario instead of AH.  Center throttle stick is the same as AH and there is deadband there so it doesn't even drift (because of the stick anyway).

What mode were you flying when you didn't like the roll/pitch?  Again, in some modes the stick is commanding speed and any quick stick motion is commanding basically an infinite acceleration to get from 0 to some speed very quickly.  To do that, it must bank steeply and quickly.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 26, 2017, 03:59:18 pm
Sorry.. I meant VelocityRoam+GPSAssist.  I used PH a while till I was confident that works and then I start using VelocityRoam instead of PH.
Now I'm flying VelocityRoam+GPSAssist (see screenshot)

VelocityRoam is also a GPS mode I should not use with GPSAssist ?  The system allows this. If I'm not incorrect I even get a config error if I do not select GPSAssist with VelocityRoam. I have to check this

I fly (1)Attitude, (2)VelocityRoam+GPSAssist and (3)RTB+Autolanding. Only 3 flight modes.
The banking angle and speed is fine in all modes.
Only in VelocityRoam+GPSAssist there is this sudden boost when the stick is moved from or to center, no matter how slow and how little you move the stick.

youtu.be/rQs-mWN-C3E   @ 0:18   here I move the yaw just a tiny little and let go right away. The time between the two boost is so small that they seem to amplify each other. (In the other video I show the same effect on the roll axis)

The boost occurs at the transition from CenterStick to non-CenterStick and vice-versa. The mode used is VelocityRoam+GPSAssist.

I don't know what else to try.  :-\

Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 27, 2017, 04:35:41 pm
Sorry, I find it hard to see how even the tiniest amount of yaw the slowest possible would jump.  :)

I gave you several options for turning this down.  How did they help?

It looks like you have negative expo set somewhere in your yaw.  Transmitter?  FC setup?
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 27, 2017, 09:40:43 pm
This is hard to believe and explain and to see on video. The copter flies fine. That jump is just unnatural. I will figure it out.
I have tried everything you suggested.
One thing I will try on Monday is to select None for assisted mode of VR. I just checked and it does not say Config Error. But the system allows both PH and VR with GPS assist.

From your reaction I understand that this combination is not common. Maybe here there is something "double" going on and is also the reason for that "boost".
I will try the following tests:
1. set None for assisted mode of the VR.
2. Tune quad in Rate to perfection and then tune in Attitude.

As I said before, I have the exact same quad with OmnibusF4+Betaflight. Everything else is exactly the same (except the props) The props for both quads is 8x4.5 but the Betaflight copter has bidirectional props.
The betaflight quad is tuned perfectly and one peculiar thing during tuning is that P value was constantly increased but there was no oscillation. The max for P is 255 and even when I tested with 250 there was no oscillation at all. I fly it with P set to 200.
What I'm trying to say here is that this copter probably needs high values and still doesn't oscillate. That's why the AutoTune showed red values twice.

The hunt for the bug goes on  ;)

Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 28, 2017, 11:27:27 pm
There was a dry period so I went to test and tune the quad today.
1. I set None for assisted mode of the VR and didn't notice any overall difference compared to with GPSAssist selected. So I will leave it to None.
2. Tuning in Rate mode (beyond default values for P) makes the copter less mushy and more responsive but also increases that Boost/jump when centering the stick.
I like the more responsive/locked in reaction but that aggressive short oscillation at the end of a movement is frightening. I wish I could only tame how hard it stops a movement. I tried many different settings, (very high P with much higher I and with much lower I, etc) but that aggressive stop with the boost/jump can only be decreased by lowering the P.

I guess I have to live with this.  :( The copter flies fine.  :)
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 28, 2017, 11:49:42 pm
another question...

I set my ReturnToBaseAltitudeOffset to 4m. Does this mean that the copter will fly at 4m above its (Armed)take off altitude on its way to base?
If I'm flying at 12m height when activating RTB, will it descent to 4m when returning to base?
I'm seeing inconsistent behavior so I'm trying to understand how it's programmed to function.

When I arm or disarm the copter there is about 1 second delay. Can this be shortened via (Dis)ArmingSequenceTime ?
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 29, 2017, 03:28:02 am
A while back I listed a VtolPathFollowerSetting that may help and I don't know if you tried it.

You can at least reduce Stabilization page Advanced tab, Rate and Max Rate and not adjust the PID.

I also suggested that you may be running reverse expo.  I can tell you for sure that some correct expo would make it where you like it.
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: JustAPilot on May 29, 2017, 06:30:21 am
I have tried everything you suggested. (the YawPI->Kp had no effect).
My rates are low and I set the max rate to 3 deg/s higher than my rates. The copter turns and banks very gently.
Expos are not reversed. I have no expos anywhere.
This boost thing I'll learn to live with it. It's a minor issue.
Thanks.

Maybe you missed my other questions...please if you have time:
I set my ReturnToBaseAltitudeOffset to 4m. Does this mean that the copter will fly at 4m above its (Armed)take off altitude on its way to base?
If I'm flying at 12m height when activating RTB, will it descent to 4m when returning to base?
I'm seeing inconsistent behavior so I'm trying to understand how it's programmed to function.

When I arm or disarm the copter there is about 1 second delay. Can this be shortened via (Dis)ArmingSequenceTime ?
Title: Re: Automatic vs Manual GPS Configuration on Revo
Post by: TheOtherCliff on May 29, 2017, 06:38:33 am
You can set expo in either the transmitter or the GCS.  That makes the center part of the stick less sensitive.  That will surely make it feel better.

Last I heard, RTB alt offset is measured from the min of base altitude and current altitude.  If you climb a mountain, it will immediately climb the offset (e.g. 4m) and stay high until over base.  If you descend into a valley it will climb straight up to base + offset before moving horizontally.