dual battery mod

It can't be with the stock GPS as the NEO-7N can receive only GPS or GLONASS not both at once.
 
From my experience, if you want a computer to run consistently you need clean power. If you have many computers, all communicating with each other, and you are trusting them with such a critical task as the flight controller on a uav, you need extremely clean power.

It may be possible with enough ferrite and tantalum to get some solos to be reliable most of the time. Adding the second battery wasn't a big deal, I just cut and soldered a few wires. The whole mod took about 30 minutes. You could probably spend countless hours chasing your tail to find what part is susceptible to what noise under what conditions. Or you could run the sensitive electronics on clean power and have fun flying a reliable drone.

Well, that's heavily dependent on your experience and capabilities. Any idiot that knows how to operate a screw driver can open up the solo, clip another ferrite bead on the GPS cable, and put the screws back in. Or, clip ferrite beads on the motor pod wires. All we need to do is identify a source for an appropriate ferrite bead, and people are off to the races with a potentially useful and easy mod to help people with a crappy stock GPS. Rewiring the whole thing and adding alternate power is a whole other ballgame. It's the different between an easy, harmless mod and reengineering.

The mRo and HERE GPS units have appropriate filtering build in and do not appear to be impacted by this electrical noise.
 
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I've read great things about the HERE GPS. I have 4 mRo units. If I have 20 Sats or less and a HDOP of greater than .6 I'm having a bad day. Not unusual for my logs to show up to 28 Sats and the HDOP to be under .5. This is on three SOLO's, and a DIY F450 with no EMI shield at all.
 
All we need to do is identify a source for an appropriate ferrite bead, and people are off to the races with a potentially useful and easy mod to help people with a crappy stock GPS.

I don't think the stock gps is "crappy" when supplied with clean power, and if it were only the gps I would agree that an extra ferrite ring around the cable would probably be OK. My experience has been that there are more problems caused by the electrical noise than just the gps. The controller also disconnects randomly when in flight. If it happens to lose gps with no controller connection, the drone is gone, and I had that happen once already. With the replacement that 3dr was kind enough to send, after the third controller disconnect / auto RTH landing I didn't feel comfortable flying the solo untethered because of that possibility.

As far as the controller losing connection randomly, where would you suggest to add the ferrite?
 
The stock GPS is indeed crappy. It has multiple design flaws that 3DR was fully aware of. The engineers didn't want to use it. But 3DR's management didn't want to spend the money on a properly designed one. So they forced it into production with a flawed GPS that barely works. When it works, it is not by much, and it drifts badly. Hence why the EKF regularly rejects it. It's mainly a lack of proper filtering that literally every GPS except this one has. This is why basically every GPS you put in the solo except the stock one works so much better with no other modifications. Your modifications are mitigating some of the noise, which is very helpful to a GPS that lacks proper filters.

As for the WiFi randomly dropping out, that is not normal. Most people do not experience this problem. I would have suggested it was a hardware problem on your first Solo that drifted away to be with the fish. That you're experiencing the same WiFi problems on the second solo is perplexing. This happens regardless of location? WiFi congestion can ruin your day, and if you're always flying in an area with heavy wifi congestion, that is what I would normally suggest. Are you test flying the modified solo in the same location you previously have problems with it dropping out?
 
The stock GPS is indeed crappy. It has multiple design flaws that 3DR was fully aware of. The engineers didn't want to use it. But 3DR's management didn't want to spend the money on a properly designed one.

Thats not hard to believe seeing how the 3.3v-5v signaling on the motor pods was handled.

That you're experiencing the same WiFi problems on the second solo is perplexing. This happens regardless of location? WiFi congestion can ruin your day, and if you're always flying in an area with heavy wifi congestion, that is what I would normally suggest. Are you test flying the modified solo in the same location you previously have problems with it dropping out?

The first solo had a reliable wifi connection with the controller, as long as the range/interference was not excessive. The only time it acted unusually was when it flew away. That was at less than 300 feet from the controller, with clear line of sight, in an area I have flown many hours before without incident. I actually had previously done many 10,000'+ flights from that exact location with no interference issues. I don't know that caused it to lose connection, and fly away. It could have been the wifi, or it could have been the linux board or some sensor, but we will never know.

The replacement has great wifi connectivity as long as its not in flight. I have done many non flight tests at both short and long range, while streaming live gopro video, and everything works perfectly for literally hours on end. Once its in the air however, after 10 or so minutes on average, the controller losses connection, and does not regain connection until I restart the controller. The first 2 times this happened, everything went smoothly, and the solo landed safely. It still made me quite nervous however, with the aforementioned gps issues. The third time however it landed in a tree, and thats was when I decided to try and do some flight tests on clean power from a secondary battery.

All of the testing on the replacement drone has been done from the same location, both with and without the second battery. There has not been a single error either from the gps or controller, or anything else, when running the second battery. Without the battery, I can't get more than 10 min without the gps losing lock or the controller disconnecting.
 
Ah ok. So it sounds like the problems with the first and second solo are different then. The GPS being lost is common for any solo due to the aforementioned GPS flaws. And ya, that sounds familiar doesn't it. The same thing happened with the ESCs. It's embarrassing really. The fly away could be any number of things like you said.

On the second one, if it doesn't reconnect until rebooting the controller, wouldn't that indicate a problem with the controller, not the solo? Possibly a heat related malfunction? In such a case, I'm not sure how noise filtering on the solo would mitigate that. I can see the noise filtering helping with the crappy GPS. But the WiFi doesn't make sense if the solution otherwise if to reboot the controller.
 
On the second one, if it doesn't reconnect until rebooting the controller, wouldn't that indicate a problem with the controller, not the solo? Possibly a heat related malfunction? In such a case, I'm not sure how noise filtering on the solo would mitigate that. I can see the noise filtering helping with the crappy GPS. But the WiFi doesn't make sense if the solution otherwise if to reboot the controller.

The controller works perfectly for hours while streaming live gopro video, as long as its not in the air. As soon as its in the air for more than a few minutes, it randomly losses connection. I have done the non flight tests with over 2000' between the solo and controller in a relatively wifi congested neighborhood, and there is no controller signal loss or even video interruption for hours at a time. From the same location in close proximity, but during flight, the controller loses connection as described.
 
It is possible that the controller might have reconnected at some point after the disconnect and auto RTH /landing, without a controller restart. I just waited until the solo landed, hoping it would reconnect before it reached the ground or other object. When it didn't reconnect, I restarted the controller just to see what would happen, and then it would reconnect.
 
Ah, so this hasn't been flight tested yet to see if the connection issue improves. I must have missed that.
 
Just remember that the Solo's that are provided as a replacement when yours "goes sideways" are all "refurbished" in other words ones sent back for a fault or some other problem that 3DR has "fixed". What are the chances of them doing a real flight test before shipping your replacement out?

Tech: "Hey all these returns have no problem here on the bench. Should I flight test them?"
Manager: "Hehehe... Ship em out!"
 
Sorry for any confusion P2P, I will try and explain what I have tested and what results I have attained.

ORIGINAL SINGLE BATTERY ARRANGEMENT:

While the solo is on the ground and the motors are not activated the controller works perfectly, no errors, with live streaming gopro video, for literally hours on end, both at short and long range. I have not seen a single error from the controller or gopro or the gps while the motors are not powered. This is with over 10 total hours of non flight testing on the original battery configuration.

While in flight the gps and controller connection randomly cut out every 10 minutes or so. Independent of range or interference/obstacles. This is with about 5 hours of flight testing with the original battery configuration, mostly on tether.


DUAL BATTERY MODIFICATION:
While in flight or on the ground it has no errors at all. Not from the gps or the controller or anything else. This is with over 10 hours of non flight tests, and now more than 20 hours of flight tests. No errors neither in flight nor on the ground with the dual battery configuration.
 
Just remember that the Solo's that are provided as a replacement when yours "goes sideways" are all "refurbished" in other words ones sent back for a fault or some other problem that 3DR has "fixed".

Thats pretty much what I thought. I am sure this replacement is one of the more error prone ones.
 
I like the idea of a failsafe reverting to the main pack. The only reason for the second battery in the first place is to give clean power to the critical components, not to increase the flight time. However with the 6 amp hour I have gotten well over 12 hours of run time with the gopro and gimbal during non flight tests. So I am thinking the 1 amp hour would last at least 2 hours in flight, far surpassing the main battery by about 10 times.
Please, keep me posted on flight times, as a Creator handling isn't a big deal because I need to fly slow & smooth to get great shots. However flight time is super important.....2hrs even 45 mins is a big-time Super modification.
Please keep me posted, thanks.
 
Please, keep me posted on flight times, as a Creator handling isn't a big deal because I need to fly slow & smooth to get great shots. However flight time is super important.....2hrs even 45 mins is a big-time Super modification.
Please keep me posted, thanks.
I think you're confused. That was 2hrs and 45 minutes sitting on the ground without the motors running.
 
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2hrs even 45 mins is a big-time Super modification.

I think you're confused. That was 2hrs and 45 minutes sitting on the ground without the motors running.

Actually you are both confused. The >2 hours time is how long a 1ah secondary battery would last either in flight or on the ground. Unfortunately the stock flight battery still only lasts about the same as it did originally. There is no appreciable difference in flight time with or without the dual battery mod.
 
I'm good with the idea, but where did u isolate the compr. parts from the motors?
 
I'm good with the idea, but where did u isolate the compr. parts from the motors?

Motor rewiring:

I cut the short red main power wire coming from the battery socket on the solo. I then soldered new wires from that red (positive) battery output wire to all the motor pods. I also cut the insulation on the black (ground) main power wire coming from the battery socket on the solo, and soldered new ground wires to all the motor pods.

Control rewiring:
I added the circuit shown in the diagram I posted, in between that first cut red wire coming from the battery socket, and the other end of it going into the main circuit board. The main battery now powers the motors and LEDs, and the second battery powers everything else.

Its pretty simple, I just made it from spare parts I had laying around. When the new 1ah battery comes in I will post some pics and simple instructions for the mod.
 
Sorry for any confusion P2P, I will try and explain what I have tested and what results I have attained.

ORIGINAL SINGLE BATTERY ARRANGEMENT:

While the solo is on the ground and the motors are not activated the controller works perfectly, no errors, with live streaming gopro video, for literally hours on end, both at short and long range. I have not seen a single error from the controller or gopro or the gps while the motors are not powered. This is with over 10 total hours of non flight testing on the original battery configuration.

While in flight the gps and controller connection randomly cut out every 10 minutes or so. Independent of range or interference/obstacles. This is with about 5 hours of flight testing with the original battery configuration, mostly on tether.

what sort of tether ?
 

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