Pixhawk flight modes
- Thread starter Chalagi
- Start date
violetwolf
Member
And (to anyone starting on Pixhawk/APM) Just because you have all the parameters and functions doesn't mean you need to use them. In 3 years of using APM/Hawk I've never gone beyond Stabilize, Alt Hold, and loiter.. nor have I have done any programmed missions... Nor have I even adjusted any PID's.. I like to fly my machines myself 
Most of the auto modes are too twitchy and jerky for video anyway so I prefer to fly manually as it's a lot smoother.
My point being that you can learn the basics and then grow into the flight controller as you go.
Most of the auto modes are too twitchy and jerky for video anyway so I prefer to fly manually as it's a lot smoother.
My point being that you can learn the basics and then grow into the flight controller as you go.
Old Man
Active Member
Once the basics for general flight stabilization are out of the way some if the greatest issues are found in how you to have to converse with the system, and the amount of data needed to do different things. It's not easy. I've been flying UAV autopilots for the last 10 years and they have a lot of language similarities. That has not made Pixhawk any easier for me though. Although similar in language with what is used in CloudCap and other Tier II AP's, it's approached differently with Pixhawk by requiring much more foundation input to do the same thing as a commercial AP. Engineering for the sake of engineering perhaps.
crayfellow
Member
@Chalagi at long last here is an example of my OpenTX setup. Remove the .txt, I had to add it in order for the attachment to be allowed.
This is inspired from a diydrones thread which also had some good examples. I think I started from Marco Robustini's settings. One change I made is that it uses two switches to enumerate 6 flight modes, but the main switch overrides the other for RTL. Also includes basic batt cell telemetry (with voice feedback when the lowest cell is getting low) and audio feedback for the flight modes.
I find this method a lot simpler as it uses a GV in the mixer instead of complex lists of values. Those live in the flight modes, which seems like where they belong. Also it eliminates the 0.5sec delay you see a lot, it was giving me problems where the Pixhawk would use the intermediary mode.
I also use Channel 8 on one of the right-side switches to invoke Simple mode, which makes it trivially easy to get a craft back requiring only a decent compass heading.
This is inspired from a diydrones thread which also had some good examples. I think I started from Marco Robustini's settings. One change I made is that it uses two switches to enumerate 6 flight modes, but the main switch overrides the other for RTL. Also includes basic batt cell telemetry (with voice feedback when the lowest cell is getting low) and audio feedback for the flight modes.
I find this method a lot simpler as it uses a GV in the mixer instead of complex lists of values. Those live in the flight modes, which seems like where they belong. Also it eliminates the 0.5sec delay you see a lot, it was giving me problems where the Pixhawk would use the intermediary mode.
I also use Channel 8 on one of the right-side switches to invoke Simple mode, which makes it trivially easy to get a craft back requiring only a decent compass heading.
When you have the motor spin up in Mission Planner set to 70 "Very slow" they are suppose to spin up when motors ar m correct? My motors will not spin at all when armed and the setting is set to 70. Is there another setting that has to match or correspond to this setting.?
Update: sorry guys I have found the answer thanks
Update: sorry guys I have found the answer thanks
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Ok this is my flight this evening. I started out in sable mode and in the video when you see my tx come into view that's when I switched into altitude mode. Altitude mode held fairly good but I don't think it was what it should have been. I know that the gps on this flight was pure carp it never even acted like it wanted to hold and in the video it looks kinda like the hexa is holding gps but I'm holding it in place because its a little tail heavy.
crayfellow
Member
@Chalagi sorry I just assumed you were using the OpenTX Companion desktop app. I have my Taranis updated to the latest OpenTX as well. The factory Taranis firmware is a bit different. Either way you could open the eepe file in Companion and poke around even if you don't end up using it directly.
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
crayfellow
Member
Even tail heavy if you have a 3d fix it will generally hold a position in Loiter. Give it another try. If you're running APM 3.3 there are beeps to confirm a flight mode change, or likewise a beep to indicate refusal to change if for instance you select Loiter and it doesn't have enough sats.
When you are flying in the open it will continually improve the fix so even if you try loiter and it refuses, you probably will be able to switch a minute or so later.
If you have an OSD that is another way to validate the flight mode it is in vs. what you requested.
Sent from my iPhone using Tapatalk
When you are flying in the open it will continually improve the fix so even if you try loiter and it refuses, you probably will be able to switch a minute or so later.
If you have an OSD that is another way to validate the flight mode it is in vs. what you requested.
Sent from my iPhone using Tapatalk
Well according to my gps on the pixhawk I had a good home lock after letting it sit for a while. And I armed and flew in stable mode and then a minute later I switched over to altitude mode. But going back into stable mode it dropped like a rock. I will try again later to see what happens and this time make sure that the hexa is balanced more on the COG. If something don't break soon this will be thrown into my junk box and a new FC will be ordered.
Old Man
Active Member
I'm not so sure some of the software updates for the Solo Pixhawk were not migrated to Pixhawk-1 software. That might not be a good thing if so. Pixhawk-2 has had a few issues.
In any case, a 3.3 upgrade should not cause a massive thrust reduction when changing from Loiter or Alt Hold to Stabilize. Loiter and Alt Hold typically assume a stick position around mid point and require the stick be moved a greater amount to climb or descend. Stabilized does not "assume" a mid stick position to do anything but command an amount of power and provides no compensation to maintain altitude if the stick position is slightly higher or lower than mid stick. Stabilized sees stick position as the amount of power/thrust commanded for the moment and does not care if that position generates a climb or descent. Do not expect mid stick position to provide a hover in Stabilized mode if your aircraft weighs more or less than half thrust would hover at when not in an altitude hold type mode. You have to fly the aircraft with manual command inputs in stabilized and be prepared to provide throttle inputs as needed to climb, descend, or hover. The point being to always check your stick position when switching from Loiter or Alt Hold to Stabilized to be certain it is a position that you know generally maintains altitude in Stabilized mode. If in Loiter or Alt Hold and your stick position was at less than mid point when changing modes you should always anticipate the aircraft will descend at a rate somewhat equal to the stick position. The reverse applies if stick position is above mid point.
In any case, a 3.3 upgrade should not cause a massive thrust reduction when changing from Loiter or Alt Hold to Stabilize. Loiter and Alt Hold typically assume a stick position around mid point and require the stick be moved a greater amount to climb or descend. Stabilized does not "assume" a mid stick position to do anything but command an amount of power and provides no compensation to maintain altitude if the stick position is slightly higher or lower than mid stick. Stabilized sees stick position as the amount of power/thrust commanded for the moment and does not care if that position generates a climb or descent. Do not expect mid stick position to provide a hover in Stabilized mode if your aircraft weighs more or less than half thrust would hover at when not in an altitude hold type mode. You have to fly the aircraft with manual command inputs in stabilized and be prepared to provide throttle inputs as needed to climb, descend, or hover. The point being to always check your stick position when switching from Loiter or Alt Hold to Stabilized to be certain it is a position that you know generally maintains altitude in Stabilized mode. If in Loiter or Alt Hold and your stick position was at less than mid point when changing modes you should always anticipate the aircraft will descend at a rate somewhat equal to the stick position. The reverse applies if stick position is above mid point.
crayfellow
Member
Sorry, I was speaking about both the Pixhawk flight controller firmware and the Taranis and OpenTX. Pixhawk runs the APM firmware (which is currently at 3.2.1, with 3.3 being released shortly).
And you're right, OpenTX 2.1.3 is the latest firmware for the Taranis and will work great with Companion 2.1.3.
As for opening the eepe, you need to make sure you're really changing the extension. Since it was a .txt it's probably leaving .txt on and just hiding it. Maybe check it at the command line.
crayfellow
Member
The Solo fork is not being merged until 3.4.
He's not running 3.3. I think he just needs to learn about how the alt hold controller works vs. linear throttle in Stabilize.
Right. @Chalagi you also should check the mid throttle setting is correct.
Old Man
Active Member
Perhaps it would be better if they maintained separation of FC software upgrades until they were certain Pix-2 code was stable. Not a good idea to mimic DJI's practice of dumping software upgrades before they are fully vetted.
crayfellow
Member
yeah. Calling it Pixhawk 2 was silly to begin with, though, as it's no more unique from Pixhawk than some of the mildly altered designs such as Pixhack. It's essentially the same. The improvements are things like "boat mode" (launch from a moving platform) and that sort of thing.
violetwolf
Member
Perfectly normal. You must put your throttle at the hover point before switching.
Although your Alt Hold worked while stationary hovering you must also test it while in motion. It should hold altitude while in forward, backward, sideways, flight for a reasonable distance. The length of a soccer field etc. This is to ensure that the machine won't lose or gain alt while on a pre-programmed mission etc. My gains for Alt Hold are usually about 1.6 to 1.7
Personally I don't see anything wrong with your flight controller it appears to be functioning fine.