Bad day to fly. Waypoints...... Never again.

[SmilingOgre]

Oh holy smoke that sound creepy, sorry for your loss! I also was thinking about Litchi or red waypoint, but after reading your "horror-story" I give up! Good luck with the new drone...They will replace it I think!
cheers Paul

Thank you my friend! I'll know soon what they have for a resolve.

 

[bcfd29]

in reading the op's explanation perhaps a word of caution is in order: plotting waypoints so closely together (five to fifteen feet as i read it) requires exceptionally precise positioning and maneuvering of your aircraft, perhaps this is well beyond what the design parameters are and there is a baseline MINIMUM distance between waypoints needed to successfully execute a plotted flight path reliably. GPS at this level is just not that precise (even for commercial aircraft or maritime vessels) and the points may have been TOO CLOSE together resulting in the aircraft logic trying to find the next plotted point which may have been almost overlapping due to signal strength, accuracy, or interference issues (hence the abrupt turn).

i defer to those who use this software more frequently, but in commercial applications points plotted too closely often cause the device to lose track of current position and next waypoint causing it (aircraft/vessel) to circle or try and recover the last known point. this typically results in a very abrupt turn or tight circle as the "confused" GPS attempts to find its last known course made good heading and position and re-acquire the next WP. standard error for hand held GPS devices is likely in the 5-15 feet (3 meter) range, while the GPS in most UAV devices are quite solid, they are also possessing some margin of known error.

when this happens on a flight deck or the bridge of a vessel, it is a simple matter of selecting heading instead of nav/gps inputs and the problem is solved, unfortunately we are not provided with this feature to quickly and easily abort a programmed course (again, defer to those regularly using the software).

somewhere in the documentation for whichever flight software package you are using there should be some parameters for minimum waypoint spacing and the degree of accuracy nominally provided. same with the accuracy for the gps embedded into your aircraft.

just a thought...

 

[ChrisOutdoors]

I've executed HUNDREDS of waypoint missions, I always launch, setup camera settings, THEN execute the waypoint mission, never an issue. I wouldn't start the mission on the ground.

 

[OldGuy]

So, I watch videos, read tutorials. Go for a flight and manually set four waypoints. I land. I take off again. Retrieve mission and hit go. Holy x#$%!!! The thing takes off like a bat out of hell and bounces off the neighbor's roof. Couldn't stop it in time. Landed the drone and replaced two beat up propellers. Noted a dent and crack in the top front cowling. Fire the drone back up. It goes through normal initialization routine to include gimbal but the gimbal settles limp off to one side. Thought I'd try to calibrate the gimbal but there is no longer a camera icon in the general settings menu. Contacted DJI, they are sending a return label.

I was hoping for a smooth flight but got a race to the ruins.

Waypoints are complicated and it's easy to make mistakes. Get a young tech guy to give you a hand to set up a mission. That's what I did and it works like a treat. I now do my own missions but get the tech kid to check them just in case.

 

[SmilingOgre]

Waypoints are complicated and it's easy to make mistakes. Get a young tech guy to give you a hand to set up a mission. That's what I did and it works like a treat. I now do my own missions but get the tech kid to check them just in case.

Did you use DJI tech support or just find a young guy that was "techy"? I'm definitely going to want to have more input before I try any of the automated routines again.

 

[OldGuy]

Did you use DJI tech support or just find a young guy that was "techy"? I'm definitely going to want to have more input before I try any of the automated routines again.

I know a young techy guy who fixes computers etc. I got him interested in helping me with Litchi for waypoints as I was struggling. With Litchi you set the waypoints up on the computer the same as GO 4 so it was a doddle for him. He was quick to pick up on all the small details you find when setting up a mission. I kept making mistakes by myself but now I have more or less mastered it but I still get him to check things out from time to time especially on a complicated mission. Once you get the hang of it waypoints isn't all that difficult so don't be put off by initial mistakes.
By the way I/we have now moved onto Dronelink for the Mavic Mini just for the experience. It also works well if you set it up correctly....the devil is in the details as they say!!

 

[hiflyer201]

The basics of Litchi are described in the free tutorials found here

Thanks! for the heads up on that course. I had used waypoints a couple of times with my Phantom 3 but have never actually taken the time to learn anything about it. This course should give me a head start if I should decide to give it a try.

 

[SmilingOgre]

I know a young techy guy who fixes computers etc. I got him interested in helping me with Litchi for waypoints as I was struggling. With Litchi you set the waypoints up on the computer the same as GO 4 so it was a doddle for him. He was quick to pick up on all the small details you find when setting up a mission. I kept making mistakes by myself but now I have more or less mastered it but I still get him to check things out from time to time especially on a complicated mission. Once you get the hang of it waypoints isn't all that difficult so don't be put off by initial mistakes.
By the way I/we have now moved onto Dronelink for the Mavic Mini just for the experience. It also works well if you set it up correctly....the devil is in the details as they say!!

I really appreciate this information. I would love to set up missions on a PC but DJI software won't operate with that operating system. I'll look into Litchi. Not sure I'm quite ready to tackle another flight program but I do want to know more about it.

 

[OldGuy]

I really appreciate this information. I would love to set up missions on a PC but DJI software won't operate with that operating system. I'll look into Litchi. Not sure I'm quite ready to tackle another flight program but I do want to know more about it.

For the $20 or so dollars you have to pay for Litchi it is well worth it. Most pilots doing waypoints prefer it to GO 4. You set up a mission on the computer without having to connect the drone, remote etc unlike GO 4 so you can take your time and get things right. I would advise once again some help initially if you do decide to go for it.

 

[SmilingOgre]

For the $20 or so dollars you have to pay for Litchi it is well worth it. Most pilots doing waypoints prefer it to GO 4. You set up a mission on the computer without having to connect the drone, remote etc unlike GO 4 so you can take your time and get things right. I would advise once again some help initially if you do decide to go for it.

Man that sounds really wonderful. If I set up a mission on my computer can I then save it to the drone and fly it with DJI go 4 or will I have to use Litchi on my android connected to the controller as well?

 

[DavidT_ NZ]

Very interesting. You'll have to walk me through "yaw error caused by launch point" can't wrap my head around that. The launch point was an area with trees to sides and rear maybe 20' - 25' lateral distance. There was also a maybe 15' overhead obstruction. Launch was manual if I remember correctly. Air craft hovered after launch @ approx 3' vertical. The drone was launched from a round orange launch pad. Activated mission and drone moved to first way point being maybe 5' away staying at about 3'. Second way point was about 15' away from the first, still at about 3' vertical. Third way point was supposed to be straight up for about 120'. It was almost as if the drone skipped the assent and combined it with the course to the 4th way point also 120' altitude and maybe 400' distance. It was during this angular assent that the drone met the neighbors roof. No indication of obstacle avoidance during this segment.

Hope that helps. Best I got.

Hello from NZ. My alarm bell went off when I read that your third waypoint had no significant XY shift but went "straight up for about 120 feet". I am a land surveyor and I have been working with precision GPS data for about 37 years. I don't know how DJI have programmed these small drones to move from point to point, but I would be suspicious of the drone veering off its recorded path when it is asked to change a height plane but not shift over a horizontal distance. I fly a Mavic Air 2 but have not tried the waypoint feature on hyperlapse filming (the only method currently programmable on that drone) but I shall do, shortly, especially after reading your posting. My initial thoughts (for my own flight plan) would be to include the home point as both the start and end points at an altitude suitable to clear any surrounding obstacles (as per the usual RTH and well above the ground terrain, to give the waypoint a good height) and then to ensure that there was a significant horizontal distance between successive waypoints, with an altitude change between them, if required. But I would not make consecutive waypoints close together in XY with a big shift in Z. It is worth trying. Also ensure that you maintain a good GPS satellite coverage reaching the drone throughout the route - i.e. tall trees and buildings obscuring some satellites along the route may cause the drone to lose itself, even momentarily. Adopting a flying height above potential (GPS) obstacles should keep the drone safe and also hold the GPS fixes through the waypoints. Unfortunately, the Mavic Air 2 is not on third party software yet for waypoint planning, so I cannot test mine that way. But your experience is certainly a warning that something weird has happened and needs exploring. Thanks for the posting. Cheers - David T ? ?

 

[vindibona1]

Man that sounds really wonderful. If I set up a mission on my computer can I then save it to the drone and fly it with DJI go 4 or will I have to use Litchi on my android connected to the controller as well?

Here's how it works... After purchasing Litchi you set up an account with log-in etc. Your account is the sync-link between everything. So when you create and save a mission within your account when you sign in on your phone in the Litchi app, it should have the mission in your mission folder. This assumes that you have an internet connection to get the mission, so I advise checking at home or where you have that internet connection. Once the mission is in your phone it's there for you. Then open it and run it.

I tried to share KML and VLM files for a mission, but the forum software wouldn't recognize it for upload.


'

 

[Jack43]

Thank you my friend! I'll know soon what they have for a resolve.

you´r welcome SmilingOgre Hopefully they have good solution!
cheers Paul

 

[VenomXts]

if you're referring to the waypoints "tasks" created using DJI GO4, you can label them within the task library.

you should see a tiny "pen" icon which provides this feature for each generically titled task.

Only have a air2 and a mini so its fly app for me... guess im stuck until that enhancement gets put in lol

 

[SmilingOgre]

My alarm bell went off when I read that your third waypoint had no significant XY shift but went "straight up for about 120 feet".

Exactly where my thoughts have been however I have nothing to support the suspicion. I know I read or heard somewhere that a 5m min shift between waypoints is recommended. Obviously, I've been reviewing the event in my mind and came up with something similar to your recommendations.

1. Get into a wide open area for testing.
2. Slow the thing down. I had it at 15mph and don't think I understood how fast that was. I'm thinking more like 3 to 5 for testing
3. Program all of my elevation changes over a later distance e.g. point 3 @5' vertical and point 4, 25' lateral distance and 20' vertical

From there I could start to incorporate your shifting of distances to see if at any point things start going south.

I've got a couple of weeks to think about it per repair and I'll review your post probably a few more times to ensure I'm not missing any nuances.

 

[SmilingOgre]

standard error for hand held GPS devices is likely in the 5-15 feet (3 meter) range

Excellent point. Been thinkin on those terms as well.

 

[OldGuy]

Man that sounds really wonderful. If I set up a mission on my computer can I then save it to the drone and fly it with DJI go 4 or will I have to use Litchi on my android connected to the controller as well?

When you pay for Litchi you download an app to your phone/tablet from which you fly your missions. You cannot fly a Litchi mission using DJI Go 4. The Litchi missions that you set up on the computer are automatically transferred from the computer to your phone/tablet via wi-fi when you switch on your device.

 

[SmilingOgre]

When you pay for Litchi you download an app to your phone/tablet from which you fly your missions. You cannot fly a Litchi mission using DJI Go 4. The Litchi missions that you set up on the computer are automatically transferred from the computer to your phone/tablet via wi-fi when you switch on your device.

Got it!

 

[Tolly]

For waypoints I find there is nothing better or safer than Dronelink. You can simulate the mission planned on your pc within Dronelink and then upload it to google earth and refine it, and refine it, before you fly so 'belt & braces'. Bit of a learning curve but great series of tutorials and very powerful and versatile.

 

[BillyDrone]

There was no steel or concrete close by. This was in my back yard. it's about 1/4 acre of grass and a few trees. I will try the log viewer over the weekend and see what I can make work. I did watch the flight from my flight records and that was accurate. Went from one point to another and when it hit the roof the drone spun in circles for a bit then continued on to the last waypoint. Looked like me getting out of bed in the morning.

Was the drone as high as you were before it took off from the launch pad?.....
Maybe there was some weed it got tangled in near by when it hit the roof.