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What's this then GPS?

nodecaf

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Esp32 etc by itself just isn't quick enough, all you get is stack overruns.

Here is the latest pic. All assembled and ready to add on.
Wow. There's so much impressive stuff going on here (and in the other builds mention in the thread). I'm trying to do a similar thing with an onion omega2, but fear weight is going to be a challenge.

Just a question, it is a bit unclear, but can you give it a destination and fully disconnect and it will go there by itself, or are you still relying on your phone to do some of the work?
 

Customerx

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Hi, the way I've got it working is you set a predetermined position on an app I've built, works out distance, bearing etc. I have my other mod which gives improved distance, because I'm building the app I suppose it could do either. As long as battery holds up. Got the weight right down now, tested working. Just having a few teething problems with the bearing settings. Tilt compensated headings aren't that easy to set up. Talk about minefield with magnetic declination and calibration. Will need to automate that part for any area. Tried many different mag sensors with accelleromators but it doesn't like it that much. Settled on a pro mini as the board (esp8266) eventually lol have a graveyard of about 15 boards I've tried so far and this is the best, lightweight low voltage and quick enough for what I need. Batteries to power the GPS and other sensors was a nightmare lol but now figured. Lightweight and powerful enough was the main issue.
29g total weight for the full addition. Still a little heavy but is working ok. Will reduce that when I print a case so I can remove the Lego adapter setup.:)
 

Customerx

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Noticed the onion is 20g by itself. When you add additional power source and GPS, accelleromator and gyro and magnetometer it's gonna be over 40g it will struggle. Was getting scalding motors to begin with but you have to Push it to get anywhere :) the TELLO can carry 60g apparently but the motors will burn out.
 

nodecaf

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Noticed the onion is 20g by itself. When you add additional power source and GPS, accelleromator and gyro and magnetometer it's gonna be over 40g it will struggle. Was getting scalding motors to begin with but you have to Push it to get anywhere :) the TELLO can carry 60g apparently but the motors will burn out.
I was hoping that the extra features in the EDU version would allow me to not use extra accelleromator and gyro and magnetometer. Not sure if I can get away with it. Also was going to use a mini board that will allow for a plugin usb GPS. While these are small and easily connected, I am indeed conserved about each gram it adds.
 
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Customerx

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Not even looked at the edu lol I guess I'm a little shortsighted on that. Did see a pretty impressive JavaScript YouTube vid that gives all the info from the drone but I've only just realised that could work.
 
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volate!lo

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Hi, the way I've got it working is you set a predetermined position on an app I've built, works out distance, bearing etc. I have my other mod which gives improved distance, because I'm building the app I suppose it could do either. As long as battery holds up. Got the weight right down now, tested working. Just having a few teething problems with the bearing settings. Tilt compensated headings aren't that easy to set up. Talk about minefield with magnetic declination and calibration. Will need to automate that part for any area. Tried many different mag sensors with accelleromators but it doesn't like it that much. Settled on a pro mini as the board (esp8266) eventually lol have a graveyard of about 15 boards I've tried so far and this is the best, lightweight low voltage and quick enough for what I need. Batteries to power the GPS and other sensors was a nightmare lol but now figured. Lightweight and powerful enough was the main issue.
29g total weight for the full addition. Still a little heavy but is working ok. Will reduce that when I print a case so I can remove the Lego adapter setup.:)
just a thought: You can replace the compass by fusing the GPS and VPS data.

GPS can give you position of takeoff and current position. VPS can give you current position relative to takeoff point (based on the bearing Tello had when switched on). By combining both positions you find the offset between Tello's bearing and the true bearing.


A simple example:
GPS reports Tello is 20m away from the takeoff point, in 270 deg true direction. VPS reports its 20m straight ahead of the takeoff point. So you know that Tello's bearing at power on was 270 deg. Now if Tello reports it has yawed 20 deg left its true bearing is now 250 deg.


To get good results you need to take off and drive Tello a few meters way in good VPS conditions to calculate the initial bearing offset. That way you don't run into problems if VPS fails afterwards.
 

Customerx

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just a thought: You can replace the compass by fusing the GPS and VPS data.

GPS can give you position of takeoff and current position. VPS can give you current position relative to takeoff point (based on the bearing Tello had when switched on). By combining both positions you find the offset between Tello's bearing and the true bearing.


A simple example:
GPS reports Tello is 20m away from the takeoff point, in 270 deg true direction. VPS reports its 20m straight ahead of the takeoff point. So you know that Tello's bearing at power on was 270 deg. Now if Tello reports it has yawed 20 deg left its true bearing is now 250 deg.


To get good results you need to take off and drive Tello a few meters way in good VPS conditions to calculate the initial bearing offset. That way you don't run into problems if VPS fails afterwards.
I think I may have found some code written in c that I may be able to use for the heading, normally the software will give you -45 to plus 45 degree tilt before it becomes inaccurate, this enables 90 degree plus or minus and looks very stable.
I'm by far not a programmer just a hobbyist so I'm learning as I go, copy and paste mastery lol
What you've said does make sense, thanks for that. :)
 

nodecaf

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Thought I'd update. Bought a D1 mini 8266 and ditched the esp32, it's lighter and works well. Been having a few issues with the electronic compass but getting there. :)
I was going to ask you, what do you use for a compass? Are you getting any issues with the fields coming off the engines? I have some concern about that...
 

Customerx

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Hi there, Ive tried a few combinations, the main issue is having a reliable tilt compensated heading. Join my onboard tello group on Facebook, I've seen your tellox and think your insight could be very helpful.


Theres been quite a few changes I've made over the last week.
 

MrKaizerSoze

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Esp32 etc by itself just isn't quick enough, all you get is stack overruns.

Here is the latest pic. All assembled and ready to add on.
Can you please provide a link to buy the GPS? or at least the part-number?

I read about the Adafruit one but it doen't look like yours.
 

Customerx

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Are you using this gps module with an ESP8266?


Using this one now :)

 

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