Posts made by Martin Lukac

@Alex-Kushleyev Hello! thank you for the response and suggestions. We got it working but I have a number of followup questions based on our experiences. They are at the end of this post.

1. The motor did not burn out as well. It was fine. I think we forgot to check if it was hot with all the other stuff going on.

2. Thank you for the link, the information is helping us understand better. Is there

3. Good news is we tried testing again with the same setup and there were no issues. We tried an alternate motor and prop as well (parts listed below). So maybe we had a short, bad soldering, or something? It was fine during the 10% power spin test which we rand for about 15-20 seconds before doing the calibration command

We used both:

• this motor with this prop
• and this motor with a 10 inch 2 blade APC prop (I can't find the link for it right now).

I put both the calibration output html files in the same folder as the previous files.

With the 10inch prop the current went over 40amps at 100% power.

We put the quads together to fly and found that with the first setup 1100kv motor and 8046 was warbling even on arming at the lowest rpm. We did a couple short 5-10 second flights. The px4 logs from the FCv2 showed showed the rpm's were really oscillating and the temperature was ramping up to 90C in about 5-10 seconds.

We put the ki and kp values to 0 and the warbling and temp issue went way.

My followup questions are:

• Can you take a peak at the calibraiton html files I put in the folder? Anything wrong stand out to you in those -- I'm just starting to understand how to look at these and it seems fine, except for maybe the amp spikes with each step. Also should we be looking for a bigger ESC if we are getting to 40 amps or over 40 amps? we dont expect to be flying full out all the time.

• In the low_kc_motor_tuning document you shared there is section on ki/kp. It says: "leave kp and ki at zero or set to mild gains of kp=50 and ki=10 to avoid oscillations". 1. is there any more documentation on these parameters? 2. By setting them to zero are we loosing the gains of having this closed loop esc? 3. Is there an automated way to find an optimal ki/kp or is it just a manual process of setting, testing, looking at data?

• I will look at the px4 code but maybe you have a quick answer. In QGroundControl, does setting the max rpm and min rpm override the parameters programed into the ESC? For example if I have two quads with slightly different configurations an I saw the FCv2 that was set for one with a max of 18k rpm to the ESC set with 14k rpm max, what will happen.

Thank you! We really appreciate the followup!

Martin.

Hello!

We have a m0138 we received a couple weeks ago. The setup we are working to test out:

• 6S battery (more details below)
• 2812, 1100kv motor
• 8046 3-blade props

During a calibration it caught fire. We are looking for help to diagnose whether this is a bad combo, a soldering/short issue, or a bad parameter, or something else we can't think of. My detailed questions are at the end and we would appreciate anyone with experience taking a look!

Note - all tests run on #2 esc/motor.

We first tested the calibration with a 6S 2200mAhr 50C battery. I did a firmware update. Then I started with this file and modified the KV (and the tones), and loaded the file onto the ESC.

I did the spin test on, and then ran the calibration and it was fine. I have plotly installed but it complained (maybe something wrong with my env) so it didn't generate the calibration html file. I did capture the console output and included for calculating the min and max rpm. See the file labeled goodtest-notes here. Everything looked fine, temps were good, motor was just little warm, current went close to 40.

I put the result of the calibration and min/max rpm into the xml file here and loaded it onto the ESC.

A few hours later a bigger battery was charged. I connected to the same setup except and did not change any parameters except I replaced the battery with a 6S 2P 9Ahr battery (also known as a P45B). The battery is 10C max continuous.

I had the same plotly issue, so see the notes_fire.txt here. You can see that it got to POW: 73, then it stalled/desynced, tried to ramp up the power again, then dropped the power, and the temp kept going up and it aborted. I was behind a door and it sounded like it finished so I looked at it was on fire. See image below.

How should we debug this? We have another couple m0138's but we are hesitant to try.

• Can you review the outputs? Does our motor, prop, battery combo make sense here (we are going for long duration).
• Could this have been a short? something about our wiring?
• Anything weird in our parameters? Did we start with a good file?
• I saw some threads about a capacitor, would adding one help here?
• What can we do to ensure there are no future issues?

Thank you!

Here is a picture of the result -- it was mounted in a frame properly isolated but we removed it:

@Alex-Kushleyev Thanks again!

For the diagram I was referring to the FCv2 side. I attached a screenshot with what I think are the discrepancies highlighted. pin6 is ground and the table shows that, but the diagram shows pin 5 as ground. Apologies if I'm misunderstanding!

M.

@Alex-Kushleyev ,

Thank you! We'll test this out and let you know if there are any issues.

Just as a FYI, I found two issues with the documentation (I'm happy to send/post these elsewhere too).

1. "Configure the Bitrate if needed (#3). For VOXL2, the default is 2000000, for FCv1/v2, use 250000." -> The motors would not spin at all UNLESS I had the bitrate set to 2000000 with my FCv2->VOXL-ESC-Mini. I spent a good couple hours trying to figure out why the motors would not spin with the actuator sliders and decided to try the higher bitrate at a whim and it worked.

2. On this page, I think the diagram is wrong , it shows ground going to the second to last pin (pin 5) on the FCv2 and it should be the last pin (pin 6).

Thanks again!

Martin.

@Alex-Kushleyev ,

Thanks for the response!

We are looking to have always 5.0V as soon as it boots up -- so a permanent setting that is remembered between power cycles/boots. I think the first option, having a ESC config param, works for us.

Thanks!

Martin.

Hello!

I have a FCv2 running px4 1.14 and 2.0.109. The VOXL ESC 4-in-1 mini is connected via J5 on the FCv2.

The FCv2 is powered by a separate step down to 5V from the battery (not the modal power harness). I can power the ESC and the FCv2 separately.

I'm able to control the motors with my RC so I know everything is working. I'm also able to test the motors through the actuators message in QGroundControl.

The problem I have is that when I arm, the motors immediately start spinning.

I think this means I need to do PWM ESC Calibration through QGroundControl, correct? With individual ESC, I think this is the equivalent step where you power them on with the throttle all the way up, they beep, and then you slide the throttle down.

So my question is, what is the proper procedure to do this PWM ESC Calibration (no props) with QGroundControl with the FCv2 and ESC Mini?

I get two error messages from QGC.

The first error: 'calibration failed: battery unavailable'. This happens when:

• The FCv2 powered only via USB and there is no power to the ESC

The second error: 'battery must be disconnected. disconnect the battery and try again'. This happens when:

• if I have power to the FC2 from the battery, USB connected to the FCv2, and NO POWER to the ESC.

I've tried various combinations of powering the FCv2 separate from the ESC - e.g. with the modal power harness (so it is reporting battery voltage) and with my own harness that is providing just 5v (since the ESC is providing the power data to the FCv2).

I've tried various combinations of all this and I get one of the two messages above.

Is there some other way to perform the ESC calibraiton or adjust parameters so I the motors don't spin when I arm?

Thank you!

@Vinny Thank you!

I'm having trouble figuring out the command based off the informatino.

I tried the command with --id 14 --val 1 ... and also --val 0, but neither make the output 5V.

I'm connecting directly to the ESC via a USB to Serial adapter and the command finds the board and is able to send the command.

The board-detect script outputs:

INFO: Scanning for ESC firmware: /dev/ttyUSB0, baud: 2000000
INFO: ESC(s) detected on port: /dev/ttyUSB0, baud rate: 2000000
INFO: Detected protocol: firmware
INFO: Additional Information:
INFO: ---------------------
ESC detected: ModalAi 4-in-1 ESC (M0129-6)
ESC detected: ModalAi 4-in-1 ESC (M0129-6)
ESC detected: ModalAi 4-in-1 ESC (M0129-6)
ESC detected: ModalAi 4-in-1 ESC (M0129-6)

Thanks again!

M.

Hello! The datasheet says the Aux power output: "3.3V or 5.0V @ 500mA (default 3.3V, SW-controlled)"

I'd like to change it from 3.3V to 5.0V. I checked the m0129 params here, but I didn't see a setting for it. Does it require a different firmware? How can I change it?

Appologies if I missed something in the documents on how to change it.

Thank you!

Martin.

When you all are testing, can you also confirm that the two USB wires are not swapped. Thanks!

I just tested my cable and it is the same issue that caused mine to melt. I sent my board for RMA so I'll respond to that email thread.

FYI it is possible to pull the pins out and swap them, but it weakens the little plastic retaining piece so it is not as solid anymore ... and it makes it confusing since the red is now ground.

I've had almost the exact same thing happen but I think ours got hot enough to desolder a part (see pictures). Feels like a manufacturing issue. Is there a way to send it in for an RMA/replacement/etc?

Here is more info:

We have a FC2.

The FC2 is brand new (purchased within the last couple months).

We did the following:

• connected the USB cable '10' to J3.
• connect a known working micro-usb cable to my laptop running QGC.
• didn't here the usual windows 'new usb device sound'

This was the first time we connected this board. We didn't see any LED's turn on within a second or two so we picked it up by the corners and noticed it was VERY hot.

We quickly disconnected everything.

We inspected the board and found a component on the bottom looks like it shifted off it's solder pads. See attached picture. We didn't inspect the board before hadn

What could have caused this? Especially given a few others have had this.

Thanks!