[K.Raghavendran]

Q: If you have ever "over discharged" the battery, then the battery may be bad and that may be your problem.

A : I have an IMAXB6AC balance charger-discharger and i make sure my total battery voltage never drops below 10.5V. I never push the limits of by battery since LiPos are very sensitive to deep discharge.  I never leave them full charged in the shelf, no puffiness in any of my batteries. I charge them 1 hour prior to flight.

Q:  It is better to flash different firmware such as BLHeli or SimonK

A: Are you talking about the peeling the heat shrink off, soldering some external wires and then flash either SimonK or BLHeli ? I have not tried this procedure yet. Since we are going to teach in schools we want an ARF(Almost Ready to Fly Kit) with as minimum modifications as possible.

Personally i have ordered some original SimonK and BLHeli. Will let you know once the courier reaches me.


Q: stock firmware will work if the settings are correct:
A : Where can i find these settings; In librepilot or some esc firmware flashing tool?

- Low Voltage Cutoff to the "disabled" or "NiCad" setting
- Slow startup OFF (or fast/normal)

Q: Buy you some LiPO alarms, set to 3.6v (per cell, it measures individual cells)
A: I have one,  , such a good buddy and i use it regularly.



Q: One test to make is to run it without stabilization and see if motors run smoothly and with plenty power.
A: I think i am ready for the leather glove technique. Will test it and post the result video here. 



Q:One test to make is to run it without stabilization and see if motors run smoothly and with plenty power.
- take props off (really!)
- transmitter not needed
- connect USB to PC and quad
- go to GCS Output page
- click all 4 boxes ("Link" column, right side) to link sliders together
- plug the battery in, in addition to USB (FC may reboot and you may need to redo the Link step)
- click Test Outputs
- click one slider
- now you can use mouse (drag slider), or keyboard left, right buttons to slowly move the sliders
- keyboard Home key stops them and End key is full throttle, practice these...
- put props on
- put a heavy coat on to protect your arm
- grab quad tightly by the bottom
- slowly increase throttle (I use keyboard arrow keys, just hold it down to do it quickly)
- you don't need to test full power, just plenty power to hover and for say 20 seconds
- press Home key to stop motors, or just hold down left arrow key is safer, because pressing End key is full power
- Uncheck the Test Outputs box and do not save settings as it reminds you that you could.

A: I use the same technique to calibrate the escs and motor spins from the configuration tab > output.
How do i choose without stabilization?


Thank you for all the valuable inputs so far, great learning.

Regards,
K.Raghavendran


   

[TheOtherCliff]

A : Where can i find these settings; In librepilot or some esc firmware flashing tool?

- Low Voltage Cutoff to the "disabled" or "NiCad" setting
- Slow startup OFF (or fast/normal)

This is an ESC thing and for "stock" (not SimonK or BLHeli) ESCs it should be described in the ESC instructions.  The way they will describe it is assuming you have a single ESC connected to the throttle channel like in an airplane.  (take props off) You start with transmitter on and throttle stick high.  You then power up the receiver and ESC (must have a motor connected to hear the beeps) with the battery and if all goes well it comes up in ESC calibration mode (not full power like the stick calls for), and if you wait a few more seconds and it switches into programming mode.  At that point, you listen to (count) the beeps (beep(1) ... beep ... beep beep(2) ... beep beep ... beep beep beep(3) ... beep beep beep, etc.) and move the transmitter stick at the correct time, according to instructions to program the various functions.

I mention this because what you see might be caused by "soft" "Low Voltage Cutoff" or "slow" "startup".  I worry that gloves aren't enough to be safe in that it may chew your arm...  Be aware that the test mentioned earlier is fairly safe in that all motors are directly controlled by the slider, but if you make a similar test in any stabilized mode (1,2,Rate,Atti) with any of the build errors that can make the stabilization go backwards, that it will automatically increase power to a very high level; much higher than the throttle stick.

If you didn't get instructions, ask your eBay seller for them.

For future reference, if this (LVC/Startup) is your issue, be aware that if you buy SimonK (or BLHeli) ESCs for a few cents more, you don't have this problem, since the firmware is designed with default settings for multi-rotor.  But I always flash the latest SimonK/BLHeli even on SimonK/BLHeli ESCs because one time I got a batch that had old enough firmware to cause some minor problems until I put the latest on it.  This is probably less of an issue now days.

Generally too, SimonK/BLHeli ESCs can be flashed/programmed through the signal (servo) connector (with a cheap Arduino, etc.), so you don't have to cut and apply new heat shrink.

[K.Raghavendran]

@TheOtherCliff

Q: Generally too, SimonK/BLHeli ESCs can be flashed/programmed through the signal (servo) connector (with a cheap Arduino, etc.), so you don't have to cut and apply new heat shrink.
A : Can you guide me towards a solid tutorial text/video so that i can start the right way. I am good at arduino, i would manage the execution part.

Q: be aware that if you buy SimonK (or BLHeli) ESCs for a few cents more, you don't have this problem,
A: Already ordered a batch of 4 for SimonK and BLHeli   

[TheOtherCliff]

That is a long topic.  Here is a Google search.  Oscar Liang is a good source.
https://www.google.com/search?q=program+OR+flash+ESC

Well first of all, you must determine the brand of the CPU inside the ESC.  For first timers, if you don't even know the brand of ESC (usually true when bought from eBay), you should probably take the heat shrink off of one and check this list (has links to pictures):
https://docs.google.com/spreadsheets/d/13tMlu5ldLNpZXwbe6UhDHJhcgTVuljm8HDiDp9WO9Pk/edit#gid=0

You need different stuff for Atmel (SimonK or BLHeli) vs. SiLabs (BLHeli only).  BLHeliSuite software works for both Atmel and SiLabs.  That is what I use or at least recommend.  I often use "avrdude" directly, which is what BLHeliSuite calls.

This Atmel CPU clip is handy, but it costs a lot of money ($25+).  Sometimes I just cut 3 sides of a square in the heat shrink (a flap just over the CPU) and program it with this.  Seems to be out of stock a lot.
https://www.ebay.com/itm/AVR-Atmel-Atmega-TQFP32-Socket-Solderless-Firmware-Flashing-Programming-Tool/183233653678
https://hobbyking.com/en_us/atmel-atmega-socket-firmware-flashing-tool.html
https://www.amazon.com/Atmel-Atmega-Socket-Firmware-Flashing/dp/B00V2W467I
You also need a USBASP programmer (about $2) from eBay or elsewhere to use this.

I always buy 5 motors and 5 ESCs at a time in case I fry one (unless I already have spares).  That guarantees that I have a match if I need one.

BLHeli_S is a version of BLHeli that supports some of the new advanced ESC signal protocols.  I don't have any ESCs that use it.