Raspberry PI attached to Spark problem - radio/magnetic interference ??

[JohnDoe5678]

Hi

I have a Raspberry PI (Raspberry Pi 3 Model B+ - Raspberry Pi) attached to the bottom of a Spark. Its inside a cardboard box attached to the belly of the Spark and does not obstruct the sensors which look downwards. The weight of the box is approx. 75 grams.

If the Raspberry PI is turned off the Spark lifts off normally and hovers at the 1.5 meter auto/default height. It can be landed afterwards without issues.

If the Raspberry PI is turned on (it is powered by 500 mAh LIPO battery) and I try to start the Spark it immediately tips over forward and does not lift off. There is no error I can see on my mobile phone (I am using the DJI GO app on Android).

I think the Raspberry PI might be creating radio or magnetic interference and is thus confusing the Spark which i turn cannot lift off.

I tried to shield the Raspberry PI with tin foil, but that did not make any difference.

My question is the Raspberry PI creating radio or magnetic interference could be the cause of the problem. If so how could it be shielded ? To confirm my assumption is there any log file I could look at.
How could I debug this situation ?

I really need the Spark to fly with the Raspberry PI attached ... any help I would be tremendously thankful for !!

Thanks

Joe

 

[MySpark53]

Hi

I have a Raspberry PI (Raspberry Pi 3 Model B+ - Raspberry Pi) attached to the bottom of a Spark. Its inside a cardboard box attached to the belly of the Spark and does not obstruct the sensors which look downwards. The weight of the box is approx. 75 grams.

If the Raspberry PI is turned off the Spark lifts off normally and hovers at the 1.5 meter auto/default height. It can be landed afterwards without issues.

If the Raspberry PI is turned on (it is powered by 500 mAh LIPO battery) and I try to start the Spark it immediately tips over forward and does not lift off. There is no error I can see on my mobile phone (I am using the DJI GO app on Android).

I think the Raspberry PI might be creating radio or magnetic interference and is thus confusing the Spark which i turn cannot lift off.

I tried to shield the Raspberry PI with tin foil, but that did not make any difference.

My question is the Raspberry PI creating radio or magnetic interference could be the cause of the problem. If so how could it be shielded ? To confirm my assumption is there any log file I could look at.
How could I debug this situation ?

I really need the Spark to fly with the Raspberry PI attached ... any help I would be tremendously thankful for !!

Thanks

Joe

Try a Pi Zero ?

Note Pi Zero W has built in wifi (conflict interference?)

 

[JohnDoe5678]

Try a Pi Zero ?

Note Pi Zero W has built in wifi (conflict interference?)
View attachment 7700

Thank you for your suggestion. Good point. But if I use WIFI on the PI Zero wouldnt I have the same problem of interference ? Or is the PI Zero different ? Would switching to 5Ghz WIFI help ? I Assume the Spark runs on 2.4Ghz ?
I will turn off the WIFI on the PI today to check whether it is causing the interference.

Is there any place in the log files where I can find out why the Spark just flips over and doesn't start ?

Thanks.

 

[Kenneth Jackson]

You probably should check that the bluetooth on the Rpi is disabled also.

 

[MySpark53]

Thank you for your suggestion. Good point. But if I use WIFI on the PI Zero wouldnt I have the same problem of interference ? Or is the PI Zero different ? Would switching to 5Ghz WIFI help ? I Assume the Spark runs on 2.4Ghz ?
I will turn off the WIFI on the PI today to check whether it is causing the interference.

Is there any place in the log files where I can find out why the Spark just flips over and doesn't start ?

Thanks.

Have not worked with Pi's or Raspbian for some time.
Just guessing that you start the Pi before the Spark/controller wifi network is started, then SSH (headless) into the Pi via WiFi (Juice SSH App available), start the vnc server (from Raspbian download), then use a VNC app with VNC server on Pi started to do a virtual desktop to ...an Android phone (client app). Once you get your Pi software going you remove wifi dongle at the USB port. Start the wifi network to the controller/Spark and hope for the best when you take off. If rc interference exists maybe you could create an under sling to increase the distance between the Pi and the Spark.

Good Luck!!

I stopped using Pi's (gps mapping of paths with a usb gps dongle) because the phone by itself was equally useful , has a variety of useable apps and has a better touchscreen interface. SSH/VNC can be troublesome.

 

[MySpark53]

Have not worked with Pi's or Raspbian for some time.
Just guessing that you start the Pi before the Spark/controller wifi network is started, then SSH (headless) into the Pi via WiFi (Juice SSH App available), start the vnc server (from Raspbian download), then use a VNC app with VNC server on Pi started to do a virtual desktop to ...an Android phone. Once you get your Pi software going you remove wifi dongle at the USB port. Start the wifi network to the controller/Spark and hope for the best when you take off. If rc interference exists maybe you could create an under sling to increase the distance between the Pi and the Spark.

Good Luck!!

I stopped using Pi's (gps mapping of paths with a usb gps dongle) because the phone by itself was equally useful , has a variety of useable apps and has a better touchscreen interface. SSH/VNC can be troublesome.

Pi zero weighs about 9 grams !!!

 

[MySpark53]

My described method , with usb wifi dongle removal from the Pi, may leave you in the data logging position of requiring a cold shutoff of power to stop the Pi.....possibly not what you need. Hopefully you are a better RPi user than me.

 

[JohnDoe5678]

My described method , with usb wifi dongle removal from the Pi, may leave you in the data logging position of requiring a cold shutoff of power to stop the Pi.....possibly not what you need. Hopefully you are a better RPi user than me.

Thank you for all your excellent comments. What is an under sling ? I cannot really turn off WIFI on the PI since I need to communicate with the Spark (it is recording a depth image using a TOF camera) to download a point cloud image.
Maybe a different frequency like 5Ghz or Bluetooth alltogether ? Funny thing is that the weight of the box doesnt seem to be the problem as the DJI lifts off normally (as long as the PI is turned off).

If I could only look into a log file and see why its tilting forward and not taking off..

 

[MySpark53]

Under sling.....like a 4 point suspension to your box corners from each of the Spark legs using cord or semi rigid connector. The box hangs below the Spark. Caution ...don't entangle the suspension material into the props on takeoff or landing.

need to communicate with the Spark (it is recording a depth image using a TOF camera) to download a point cloud image.

Not sure I follow that one clearly. If you're downloading data actively in flight or more likely post flight.

I get the point cloud idea.....maybe an autonomous waypoint flight with Litchi software would be useful for you to pre-configure your actual flight path ...... Hands off flying...

 

[JohnDoe5678]

Under sling.....like a 4 point suspension to your box corners from each of the Spark legs using cord or semi rigid connector. The box hangs below the Spark. Caution ...don't entangle the suspension material into the props on takeoff or landing.



Not sure I follow that one clearly. If you're downloading data actively in flight or more likely post flight.

I get the point cloud idea.....maybe an autonomous waypoint flight with Litchi software would be useful for you to pre-configure your actual flight path ...... Hands off flying...

I am downloading data during the flight (capturing a sequence of pointcloud frames/pictures of an appartment).
But it is not used for controlling the Spark.

Would'nt a box hanging below the spark obstruct the downward facing sensor ? Or can I fly w/o it ?
If I could fly safely (w/o need of the downward looking sensors) and land the drone by hand I would prefer to do so. As the box is it is attached now is placed backward in order not to obstruct the downward 2 IR sensors+camera.

 

[MySpark53]

Would'nt a box hanging below the spark obstruct the downward facing sensor ?

Yep.....

downloading data during the flight

Sounds complicated.....
The box mod violates the warranty on multiple levels
"Make sure that you only fly your drone in an area without radio interference, as this can also lead to damage that is not covered by the warranty.'
Also:
In your box mod 'turned off' test you might want to check how long your batteries last ....

Maybe with your expertise you could build a non-Spark drone from a kit with capabilities more suited for your described point cloud task....

 

[MySpark53]

While it might seem that you have a case of 'point cloud' addiction (with the Spark fulfilling the high) a Google search on TOF cameras does reinforce the idea of paring TOF with drones (ultimately in a final product sense).

Time of Flight Camera Sensors On Drones And 10 Terrific Uses

Good luck attaining your 'point cloud' objective with some kind of drone.

 

[HOVER]

I think the Raspberry PI might be creating radio or magnetic interference and is thus confusing the Spark which i turn cannot lift off.

I tried to shield the Raspberry PI with tin foil, but that did not make any difference.

My question is the Raspberry PI creating radio or magnetic interference could be the cause of the problem. If so how could it be shielded ?

Try incorporating an electro-static ziplock bag instead of foil. Like the one you get with a new hard drive, memory or other computer parts.

 

[MySpark53]

Given RPi wifi range issues and possible interference with Spark's controller wifi the idea of doing some kind of in flight on board LIDAR IMAGE desktop screen capture (or with windows software on a Latte Panda board(?)) would eliminate the RPi wifi issue all together if it should be a problem.
Fascinating 'bleeding edge' technology idea!

 

[MySpark53]

Syma x8c lift load capacity is in your range requirement

How Much Weight Can A Small Drone Carry? | UAV Systems International

An FPV drone kit that might work