3DR Solo with LiIon 9000mAh battery | up to 30min flight time

[webbs]

This may be a stupid idea, but here it is...

How about a smart, translating BMS? It seems that maybe a new smart battery module could be made that uses a micro Arduino connected to the original 3DR Solo battery BMS, which reads the new battery data and then emulates the original BMS for the 3DR Solo, sending translated and scaled battery data appropriately?

The Arduino code could scale the battery capacity so that a full 10,000 Mah pack would look like a full 5,000 Mah pack to the 3DR Solo? You could scale the reported Mah remaining, and you could also scale the battery voltages, to make return to land happen at the correct voltage for a new battery chemistry?

In theory, it seems that this could work without adding wires to the Solo Cube?

Chris Shaker

Hi OldCoder,

I have been working on something like that. It uses the voltage to determine remaining capacity rather than measuring actual capacity used. This way you can use any sized pack and it will send through remaining capacity based on a max voltage for 100% and min voltage for 0%.

Generic Battery + Arduino = Happy Solo

 

[Derriell]

Hi

I think it is great to have the arduino option especially if you dont want to mess with the Solo board or BMS and risk it. Nice hacking @webbs : )

Me personally I prefer to use a power board, and for me it was worth the risk because of the following reasons:
- It is lighter (no bulky connectors, no arduino etc.)
- It has more space available
- For me it is less of a hassle, just be able to plug two cables and I m good to go

I think most soldering experts around the corner should be able to do the job and for less than 50$.

For what I have written in this thread (I mean that if you decided for a solution in this thread, not that you should decide for a solution in this thread) I do recommend for anyone who wants to use the Solo regularly and fly non-stock batteries to use the power board method and not try the mess with the Solo BMS and the python script. As the Solo-BMS is limited to 5200mAh and inconvenient to deal with (reset etc.).

Have a nice day

 

[makatanav]

Hello on 2nd Easter

Finally installed mRo Hall Sens Power module ACSP7 (Next Gen).


But have some questions.
The configuration instruction is based on older version of software

Found where and what to configure in MP:


In MP it shows likt this (board sitting on the bench - showing 6.44V 28.2A )


When adjust the Voltage:


Should it be so? I`m more about those 28.2A? Or it’s a calibration question? Or something wrong with the hardware?
Or some different new parameters need to be added in MP?

 

[Derriell]

Hello on 2nd Easter

Finally installed mRo Hall Sens Power module ACSP7 (Next Gen).
View attachment 11011 View attachment 11012

But have some questions.
The configuration instruction is based on older version of software
View attachment 11013
Found where and what to configure in MP:
View attachment 11014

In MP it shows likt this (board sitting on the bench - showing 6.44V 28.2A )
View attachment 11015

When adjust the Voltage:
View attachment 11016

Should it be so? I`m more about those 28.2A? Or it’s a calibration question? Or something wrong with the hardware?
Or some different new parameters need to be added in MP?

Hi

Nice!

I suggest to swap the two wires that go to the Pixhawk who transmit Ampere and Voltage telemetry. I got this wrong when I installed it and got some weird measurements like yours. There is no damage to be done there. It might be a good chance that in my instruction it is the wrong way round. Sorry about that if it is the case. I tested it the following way: I armed the drone and started the motors. If it was the "voltage" value that was changing more than the "ampere" value, than it is the wrong way round.

About the parameters. It looks good from my point of view. Of course it depends on what you want to set. I think most parameters are self explaining.

EDIT:
As it turns out, my cabeling instruction for the telemetry cables were wrong and the ampere and voltage telemetry cables need to be switched. I will edit the start post. If you did it the wrong way no harm could have been done to anything, just wrong telemetry readings. This is correct:
Pin 4 BATT_VOLTAGE_SENS_PROT connect with pin 47 on Pixhawk
Pin 3 BATT_CURRENT connect with pin 49 on Pixhawk

Thank you @makatanav

 

[Ralph E. Johnson]

If any in the US finally gets the solution for the dying batteries please let me know. To even get a 20 min flight time and have access to batteries would be major. I would like to get my Solos changed to accept a new battery.

 

[makatanav]

If any in the US finally gets the solution for the dying batteries please let me know. To even get a 20 min flight time and have access to batteries would be major. I would like to get my Solos changed to accept a new battery.

Thera are actually 3 options now:
1. Get extracted battery BMS and use any LiPo till 5200mAh (or extract yourself),
2. BMSOne - BMSOne – the universal BMS – Madhacker.org = but due COVID-19, shipping is slow (sends fron Norway), some on facebook group has already received (still will need soldering job)
3. Power module way (will need accurate soldering)

price wise, all will be ~ the same, but will have their +/-

 

[webbs]

Thera are actually 3 options now:
1. Get extracted battery BMS and use any LiPo till 5200mAh (or extract yourself),
2. BMSOne - BMSOne – the universal BMS – Madhacker.org = but due COVID-19, shipping is slow (sends fron Norway), some on facebook group has already received (still will need soldering job)
3. Power module way (will need accurate soldering)

price wise, all will be ~ the same, but will have their +/-

There is also the option of Generic Battery + Arduino = Happy Solo which will interface between the Solo and and any battery but currently requires you to build your own circuit and program an arduino if this is your type of thing.....

 

[VCD]

Did anyone beat the battery configuration/results from @Derriell 's first post?

 

[Professorpip]

Did anyone beat the battery configuration/results from @Derriell 's first post?

I got over 25 mins (with gopro + gimbal) with a 10500mAH (on paper, at least) Sanyo Li-Ion pack and the Happy Solo BMS alternative about 3 months ago - so a couple of minutes longer than the comparable flight. On that basis without gimbal + gopro I'd have got 33 mins or so - but I don't ever fly without the camera+gimbal on board.. All the details are in the Happy Solo thread.

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I did this as the Sanyo cells have 500mAh more per cell (although a 10A max discharge rather than 15A for the Samsung's), I also had slightly larger than stock props which according to my experience help the solo cope with the extra mass of the larger battery a bit better. I was worried at the time that I had gone under 2.5 v on one cell - but it turned out the calibration of my sensor was slightly off and so this was not the case, and the battery pack has flown fine since (getting similar performance as per that video - although I don't usually push it to the max in the way I did as an experiment then). Interesting note is that the heavy solo never pulled more than 30A - so that looks like 4s3p Sanyo packs can cope with this within spec - they weren't hot on landing - so if someone want's to push the duration to the limit, I think the Sanyo cells are probably the best bet at a reasonable price. The samsungs are great too (and I guess would probably live longer as operating more comfortably within their max current range) - so it's maybe a trade off for the sake of 2-4 extra minutes.

 

[Derriell]

Did anyone beat the battery configuration/results from @Derriell 's first post?

I think a "problem" with the Solo is, that it is a bit on the heavy side compared to its size (and propeller size). Thus if you would want substantially more flight time I think there would be no way around a custom frame with the Solo guts and bigger propellers (12"). To my simple calculations it would be possible to build a "3DR Solo"-sized drone with 40-45min flight time with the gimbal and GoPro.

@Professorpip Nice project! What was your take off weight? Which cells did you use, Sanyo NCR18650GA? Btw. I would go for new cells, as the internal resistance of the cells is quite important for this kind of application. With used cells you dont know what they have been through and could get a cell drift. I use to buy cells from nkon. What was your average power consumption in hover flight? In my experience when the LiIon cells hit ~2.8V they haven't much energy left inside.

 

[Professorpip]

Hi - My custom batt pack was 668g - ie +175g heavier than a stock solo batt. Not sure what AUW was, but next time I fly I will weigh the whole thing. You're right - it was the Sanyo NCR18650GA's and I bought them brand new from nkon (best source in Europe/UK I think). Average power consumption was under 26A at all times (I do have a log of the Wattage / amperage in hover when the readings were better calibrated- but it's not handy right now). I recently bought a GoPro Hero 7 - so I'm thinking I should be able to get +30mins (with the gopro7 in hypersmooth mode, and thus not needing the 3dr gimbal). Agree it would be very interesting to do a solo transplant into a bigger frame. My APC 11x4.5 props do certainly make a difference in terms of carrying the heavier battery whilst keeping prop rpms not-too-high.

 

[makatanav]

did a 1st test flight yesterday
Power model mode just like @Derriell (big thanks for inventing "the bicycle" so we could ride with it)
Temperature 7C, wind 3m/s, hover on altitude 15m
30Q Li-Ion battery, charged 2nd time
Got 20min 20sec from 16.3V down to 12.4V with my 1940gram 3DR Solo (MasterAirscrew props)
Average draw ~19A
So I guess it will get little better with further charges and charging it to 16.8V.

Have Warning, Battery differential: xxxxxmV but will look how to deal with it.



will add build info later this week in My introduction thread: LV 3DR Photo Drone

 

[Professorpip]

did a 1st test flight yesterday
Power model mode just like @Derriell (big thanks for inventing "the bicycle" so we could ride with it)
Temperature 7C, wind 3m/s, hover on altitude 15m
30Q Li-Ion battery, charged 2nd time
Got 20min 20sec from 16.3V down to 12.4V with my 1940gram 3DR Solo (MasterAirscrew props)
Average draw ~19A
So I guess it will get little better with further charges and charging it to 16.8V.

Have some errors, like ekf3 imu0 ground mag anormaly, yaw re-aligned and Warning, Battery differential: xxxxxmV but will look how to deal with them.



will add build info later this week in My introduction thread: LV 3DR Photo Drone

That's great - thank's for sharing the photos...

I think, if you wanted, you could go down to a lower voltage - at least according to the 30Q specs (e.g. here https://eu.nkon.nl/sk/k/30q.pdf) According to the discharge graph on pg 6, at 3.1 v per cell (assuming a 10A per cell average draw - i.e. the green line), you'll have used about 2.4 Ah per cell, wheres you could get to about 2.8 Ah i.e. +400mAh per cell more), by dropping down to 2.8v per cell (which is still above the minimum discharge of 2.5v per cell for these types of cell) - hence there's about 16% unused "juice in the tank" at that end of the curve, and according to the graph on pg 9 the deterioration over ~300 full cycles is not that bad really... So that could bring you to the 23-24 min flight time region, who knows maybe even 25 mins with a full charge to start.

 

[VCD]

My Samsung 18650-30Q 4s3p pack is 623g
My Sanyo NCR18650GA 3450mAh 10A 4s3p is 590g

Both get good and warm at the end, I "always" fly down to 2.5v on the lowest cell. usually get 22-23min. (stock propellers and gopro4black)
I did not test with the Master Airscrew, once when I bought them I just found out that the energy consumption did not seem any lower, so I disregarded them as something good.

 

[jxo]

My APC 11x4.5 props do certainly make a difference in terms of carrying the heavier battery whilst keeping prop rpms not-too-high.

Just checking, you are using 11" props on a Solo? Correct?

 

[RichWest]

Both get good and warm at the end, I "always" fly down to 2.5v on the lowest cell. usually get 22-23min. (stock propellers and gopro4black)

So this is basically a 4S battery, does that mean you are running solo on 10VDC?

Sorry, I'm confused, wouldn't the amps be off the charts at that voltage and draw-down?

 

[Professorpip]

Just checking, you are using 11" props on a Solo? Correct?

Yes sir. My sense is when flying with a heavier-than-stock battery is that larger props are useful. In full disclosure, my test flights weren't 100% like for like, so I can't swear to it and I've not wanted to take the 11" props off my solo since then. But my sense was it helped. Maybe once lockdown is over I'll be able to do an apples-to-apples test with both of my Sanyo 10,500mAh 4s3p li-ion packs - comparing flight time from stock props vs 11" props.

 

[Professorpip]

So this is basically a 4S battery, does that mean you are running solo on 10VDC?

Sorry, I'm confused, wouldn't the amps be off the charts at that voltage and draw-down?

Yes it does mean one can go as low as 10v. However if you look at the capacity curves, if there's not much difference in terms of useful capacity / flight times if you land at 11v or 10.5 vs 10v (as at that stage the voltage is dropping off like a cliff)..
Obviously - Wattage (power) stays constant to maintain a hover throughout a flight... So at the start if the pack is at >16 volts, and at the end the pack is ~10-11v then there has to be an approx 50% increase in Amp (current) draw so as to keep power constant.
In my tests (although I did have issues in calibrating my shunt resistor current measure), I was drawing about 20A at the start, and just under 30A at the end (the limit for the Sanyo 4s3p pack).

So it means in a sense I think the Sanyo packs are close to optimal in the 4s3p configuration (max current 10A per cell), whereas the Samsung's (at max current of 15A per cell), could also cope at 4s2p.... Interesting that a Samsung 4s2p pack would have 6000mAh (i.e. about same power as stock), but would weigh about 400g (which is about 100g less than stock solo lipo).... As the solo with stock batt is about 1.5kg, that would be about a 10% AUW reduction. D'Oh - As I write this - realise Derriell (in this original thread post), and later (3DR Solo with LiIon 9000mAh battery | up to 30min flight time) already described this much better than I have just done.... However, I don't know if anyone has actually done a real Samsung 4s2p flight-time test ??? (w gimbal + gopro of course!).... It should be more than stock for sure, but is it going to be better than the Samsung or Sanyo 4s3p ... (which can do >25 mins flight time in my experience).

 

[makatanav]

Just checking, you are using 11" props on a Solo? Correct?

I have also 11" props, but for now havent seen much of a difference on my tests.
Yes they are stiffer than MasterAirsrews, but need to test more to see the real results

 

[Professorpip]

I have also 11" props, but for now havent seen much of a difference on my tests.
Yes they are stiffer than MasterAirsrews, but need to test more to see the real results

Someone did a comparison of (1) stock, (2) APC 11", and (3) MA 10.5" 2 blade here on a 'normal weight' solo... (elsewhere there are tests showing the 3 blade MA is worse for efficiency).. The 2 blade MA's were best... The 11" was very close behind... The stock was 3rd (about 8% worse than the the others..

See Solo Props: APC, MA & Stock. Battle For Power..

My observation is that with a heavier batt pack the 11" props take the lead for me.. But I can't quantify by how much (not much really I suspect- maybe just a few Watts, translating into a few 10's of seconds extra flight time perhaps).. So it could be that MA 2-blade and APC 11" options are so similar efficiency wise (within 1%) it hardly makes any noticeable difference, allowing for experimental error etc. So then it comes done to preferred flying characteristics (smaller props = more nimble, larger props = more stable??)