Tapping power

[kbowerma]

I have been working on an external GPS location tracker based on the particle photon and electron. I am prepared to use a single cell lipo but would like to see if there is an elegant way to tap into the flight battery. I don't think I can use that micro usb port on the side while in flight? Does anyone know? I will need to deal with the compass when I mount this thing on top but I am willing to give that a go. Thanks in advance.

 

[Crusader]

Maybe this teardown of the flight battery can help!

 

[F6Rider]

Hmmm, isn't that the asset tracker? It uses the 3G or 2G Electron to communicate with the Particle Cloud. The kit is small & fairly light, but adding the waterproof case adds to that. Not sure what the finished size & weight is, but it will for sure affect the flight range of the Mavic, more so when pulling power from the quad's battery. Interesting project, keep us informed as to your progress. If anyone is interested in learning more you can research it HERE

 

[kbowerma]

Hmmm, isn't that the asset tracker? It uses the 3G or 2G Electron to communicate with the Particle Cloud. The kit is small & fairly light, but adding the waterproof case adds to that. Not sure what the finished size & weight is, but it will for sure affect the flight range of the Mavic, more so when pulling power from the quad's battery. Interesting project, keep us informed as to your progress. If anyone is interested in learning more you can research it HERE

Yes, I have the asset tracker product too and the case is a little bulky, I have been developing on the photon since it is easier to debug, but should move back to the electron later this week. The asset tracker library is pretty week, as is the ultimate gps lib. You can't even get altitude, believe it or not. I switched to the tinygps library and it is great, small and easy to use. Even has speed calculation built in that are pretty accurate. I also upgraded the accelerometer to the lsm303 which is a little better then the lis3dh since it has a built in magnetometer. And I use a $9 oled which makes life easier to develop with. I will post my repo if anyone is interested.

@Crusader, That is awesome thank you so much. The idea of tapping the battery makes me feel much better, worst case is I screw up a battery.

 

[F6Rider]

@Crusader, That is awesome thank you so much. The idea of tapping the battery makes me feel much better, worst case is I screw up a battery.

The only issue I would have is having to mod each battery.

 

[kbowerma]

The only issue I would have is having to mod each battery.

Yeah I would be fine with doing just one but it seems like they don't want to come apart.

 

[Crusader]

Yep, see what you mean. If you look at the 2nd pic (not mine) top left corner it takes brute force to open.

 

[Ed209]

Cool project. Any reason why you wouldn't just use a simple RF-V16 tracker? It runs on it's own battery and will continue to log position even after a crash/landing. I use it all the time with my P3's and have saved my *** plenty of times. You could open up the Mavic and tap the main power but that will be 13.05v when fully charged. Here's some pics...The white/black wires are what you're looking for. I haven't bothered to look for lower voltage taps on the board but there may be other options.

Edit: Forgot to add, you can run your leads out the folding joint in one of the front arms... It's very easy.

 

[F6Rider]

That would work, but you will be voiding both your warranty and any 'Care refresh' you might have, also, you would need a 5VDC power source in the quad, the 13.05 VDC from the battery would fry the tracker. But my question is why? the tracker has it's own rechargeable battery, unless you want to remove it from it's case and install it inside the Mavic, which I don't see as an option.

 

[kbowerma]

Cool project. Any reason why you wouldn't just use a simple RF-V16 tracker? It runs on it's own battery and will continue to log position even after a crash/landing. I use it all the time with my P3's and have saved my *** plenty of times. You could open up the Mavic and tap the main power but that will be 13.05v when fully charged. Here's some pics...The white/black wires are what you're looking for. I haven't bothered to look for lower voltage taps on the board but there may be other options.

Edit: Forgot to add, you can run your leads out the folding joint in one of the front arms... It's very easy.

Thanks that is a great tear down pic. I wish I had the guts to take mine apart like that. The reason I am not using a GPS tracker like RF-V16 is that we are building a platform to accept location and telemetry that can strap on any drone. (It worked fine on the Solo, but the mavic has far less strappable real estate) If the the loc update happens to be in a "no flyzone" it will set off alarms on the tracker which will flash leds and sound an alarm. But I guess the real reason is that we need to customize the endpoint and payload. You can see a little more here: GitHub - kbowerma/droneTracker: particle client for tracking drone. I am able to send an update every 20 seconds with the Particle Photon now only when I am moving. I also found a really nice 500mah 3S battery on Amazon. It went from full charge to 10% in 3.5 hours with a LM7805 to power the Photon, GPS, accelerometer. The tail lights / buzzer will power directly off the 12V battery via a Mosfet. I think I can get more out of the battery if I switch to a buck converter.

 

[Ed209]

Thanks that is a great tear down pic. I wish I had the guts to take mine apart like that. The reason I am not using a GPS tracker like RF-V16 is that we are building a platform to accept location and telemetry that can strap on any drone. (It worked fine on the Solo, but the mavic has far less strappable real estate) If the the loc update happens to be in a "no flyzone" it will set off alarms on the tracker which will flash leds and sound an alarm. But I guess the real reason is that we need to customize the endpoint and payload. You can see a little more here: GitHub - kbowerma/droneTracker: particle client for tracking drone. I am able to send an update every 20 seconds with the Particle Photon now only when I am moving. I also found a really nice 500mah 3S battery on Amazon. It went from full charge to 10% in 3.5 hours with a LM7805 to power the Photon, GPS, accelerometer. The tail lights / buzzer will power directly off the 12V battery via a Mosfet. I think I can get more out of the battery if I switch to a buck converter.

Taking the mavic apart is not that hard at all. Waaaaaay easier than any of the Phantoms. How much does that battery weigh? How much current do you need from the battery? I may have some better options in mind. Good luck with your endeavor and really nice work!

 

[kbowerma]

Taking the mavic apart is not that hard at all. Waaaaaay easier than any of the Phantoms. How much does that battery weigh? How much current do you need from the battery? I may have some better options in mind. Good luck with your endeavor and really nice work!

I don't know how much power I will need. The photon, gps, oled and accelerometer worked fine of a single lipo but I know that is not enough once I add the light a siren. So I have been playing with small (500mah) 3s lipos which is adequate but I keep over discharging them. I have a couple of 2S which come today. I was taking them through a voltage regulator (LM7805) but switch to tiny UBEC instead. I should know in a couple of days the final draw but I don't expect it to be more than 550mA