55A ESC Testing: BLHeli_32, BLHeli_S, BlueJay, AM32 

I appreciate all of your hard work Chris! Please keep it up and great work brother.

Keep the info coming, Chris! At 4:07 I'm seeing that at 10% throttle, a single motor with a 5" prop generates 800g of thrust. If that were the case, wouldn't all our quads just take off the instant we arm, with 4 motors generating roughly 1.6kg of thrust at 5% idle throttle? It also seems really strange that 100% throttle is only 2.25x the thrust of 10% throttle. Something about this data doesn't seem right to me.

Fascinating testing results indeed, Chris! 😃 Looking forward to see more of them! Stay safe there with your family! 🖖😊

I think this is a topic you should continue investigating. Though it may be impossible to nail a winner, we as a community are aware that there is no such thing as a free lunch. We just want to know what might suit our flight style.

I would love to see how ESCape32 works on those am32 escs. I had very good results with it

Looks like testing ESCs has some challenges. Kudos to you for discussing this openly and transparently. The responsiveness data is fascinating. Thank you for doing this testing. I was thinking of trying out AM32 but I think I'll hold off for now.

Interesting vid Chris! thanks for doing this work. I have one question about the torque vs acceleration results. Since torque is proportional to angular acceleration, how does blheli32 do worse in the torque test, but then do so much better in the acceleration test?

very interesting tests, as always! thanks

thanks for doing this testing!

Great video Chris, thank you

The problem I see with using a flywheel for testing is that you load the motor at very low rpm where a prop would still have almost no load, this could be where the difference between firmware is showing up, with the blheli 32, it may be, for instance, that the load at low rpm is just not being detected as a normal operating parameter.

I'm confused about how we can determine anything about the software if it is running on different hardware. wouldn't we need the same hardware running the different software to see any difference between software? I fail to see what was accomplished here. I appreciate the time but, I'm not sure that this is a good way to see differences in software.

Great work!

The increased acceleration of BL_Heli32 is the most noticeable characteristic that I experience when trying any other firmware. It probably has a lot to do with my flying style but it's something I can't overlook when using other FWs.

The ESCs differ also by the dead times that the FETs need. How much of an influence does this have on the parameters? Ideally (I know it it a wish) we would compare the ESC firmwares with HW / settings realizing the same boundary conditions.

Definitely very interested in seeing if there is any extra performance that can be squeezed out of bluejay. That difference with bl_32 is quite considerable.

great vid!!

I am kind of curious how the old tgy code compares these days! It sounds like the major change is variable PWM frequency ("ByRPM"), which would be fairly simple to add. Meanwhile, dshot would not be fun to implement -- I avoided it as it meant many more interrupts. I did test ludicrous update rates by furthering the "onshot125" concept, so maybe it would be fine. Anyway, good to see that things are still changing and improving, and measurement is key!

I swear by BLHeli_32 for "3D" flying. I am really curious about Motor Rampup and other settings to get acceleration on AM32/BlueJay ESC's to increase. Personally running Motor Rampup of 100% (default is 50%) and it makes a noticeable difference in the air.

There's a current limit and rampup power, both of which affect that max torque. I'd really like to see some of these comparison tests with that set to different ones - eg make sure the tests are done without the cirrent limit enabled, then try the default rampup power and compare it to the torque with max rampup power selected, and then compare those two results to the other ESCs' results. (And do the same thing with the other firmwares.) Otherwise what we're really comparing here is the ESC firmwares' default settings instead of the ESC firmwares themselves (which you kinda touched on in the video). Also, how is the acceleration/deceleration for Blheli_32 so high when its torque is lower? I would've thought those two would corellate?

this is awesome! I just wish you used ESCs we use.

Look at the old dronemesh channel and the electrical noise testing he did - high levels of electrical noise would impact filtering tuning. Would recommend testing the Xrotor ESCs.

I would think to compare firmware, the ESCs hardware needs to be pretty close. For example, did these all have the same Deadband?

would it make sense to identify the FETs used and compare ESCs with same FETs and different firmwares?

awesome video, with smaller quad being more and more popular especially with 2.5" and 3", can you do a similar test with a 1404 or 1604 motor?

Research of ESC efficiency I would start with wiring optimization. 50A at the top of acoustic frequency just beg for using twisted Litz pair! Simple experiment: check efficiency and dynamics on one ESC, prop and motor connected with recommend gauge wire, twisted and not, then the same with electrically equivalent gauge Litz, twisted and not. This may have bigger effect than variety of ESCs gives!

So what you're saying is I need to change my BLHeli_32 settings back to default. Got ya. Thanks.

Hi Chris, have you tried re-flashing the different ESC's with for exampleSpeedybee Blue JAy with BL Heli 32 to see if their performance changes?

This is great...i believe it may explain some of the issues I've had with AM32. The PIDs must be dialed down quite a bit. The low-end torque on my high KV motors is too much. (2207 RCINPOWER 2040kv). I would love a video on AM32 settings. I've tried several, and I'm just not getting the smooth performance i was expecting. Thank you for everything you do for us in this hobby!

am32 you can set the kv slider lower to allow higher acceleration of the motors at the cost of over current protection.. personally I start at half your motor kv for the slider and take it lower till it wants to not run clean..

Great video, as usual. Thank you. With regards to the surprising amount of extra torque that BL_32 seems to provide: How about using a scope/logic analyzer to record the actual signals coming from an ESC microcontroller its the FETS during the acceleration, for BL_32 and AM32? This would also require recording a timing signal in order to get actual timing data of the signals. This could be done, for example, by placing a hall switch close to the bell. Or by making a reflective / dark mark on the bell and recording its passing. Graphing the pulse-frequency(for bi-rpm), -width and -phase with regards to the timing signal, you might be able to get some useful information as to. At 24Khz, that's a lot of data, but a single capture should not last longer that a second and with some coding, much of the analysis could be automated I presume.

Hi Chris, I appreciate all of the excellent bench testing, but you absolutely have to fly and try tuning a quad using the ESC to see if it actually works in a Betaflight quad. I have had two Skystars ESCs (the same Kamram 55A 20x20 and 30x30 AM32) and both have produced nearly unflyable and untunable quads. There was so much oscillation and also strange sounds coming from the motors. And I used your AOS EVO 4" and 5" frames, so we know that resonance was not the cause. Everything worked perfectly when I switched to iFlight BLHeli_32 ESCs. Someone, somewhere, said that AM32 doesn't work well because it produces more torque and suggested dialing down the d-term. But I couldn't see much, if any, difference when I tried that. Ultimately, I don't know if Skystars ESCs are junk, or if AM32 might not work well with quads. Perhaps I was incredibly unlucky. However, I have seen similar complaints online about the Skystars AM32 ESC, and also that some NeutronRC AIOs with AM32 were untunable. I'll be avoiding Skystars and AM32 for a while until they both build a decent track record.

I would have liked to see a more even playing field with as close to the same esc's as possible. Skystars makes a 55a in Blheli-s, blheli32 and am32 flavors I'm guessing they all use the same fets and board layout. They could probably provide the best results as there are definitely some differences coming from the fets, board layout, copper thickness, heatsink, etc.

The reason for the poor blheli32 performance in the torque test may have to do with the "Low RPM Power Protect" setting. I tried to power a quadcopter with 15" props with T-Motor 3510, 630 kv motors and the T-Motor F55A Pro ESC with BLHeli32, and I got abysmal performance, thrust was pretty much flat above 25% throttle. I am fairly new to all of this, I spent two years (!!!) pretty much replacing every part of my setup, figuring that each component individually was working fine, but the combo of motor and ESC just didn't work. Then I set "Low RPM Power Protect" to "off" and, "wroooom", I suddenly got full power!! Seems that at low RPMs, blheli uses a heuristic to determine whether the props are stuck by looking at "unusually high" current draw. And for a firmware written for small FPV quads, the current drawn by a low kv motor with large props, and probably by a flywheel, is unusually high. I am trying to spread the word about this as I find it hard to believe I'm the only one who get stuck with this...

If u can,pls do a latency test with the walksnail goggles and the sharkbyte vrx and with the 90fps cam

I appreciate you say you have not finalised your test protocol, but surely you need to use the same firmware on each of the ESCs in turn in order to provide a meaningful comparison. I would be interested to see if the noise levels generated by the ESCs are impacted in any way by the firmware used.

Hi Chris- every test opens up more questions- would you get the same spread of results using a motors? Ditto for props? Keep testing, it’s great that someone is producing some facts rather than just opinions For a long range efficiency conclusion would we need a different test - efficiency at a stable 40/50/60% throttle level?

The question for me here is does that top performer efficiency actually translate to more thrust when the system becomes power limited by smaller cells and more motors

You should compare different brands of the same firmware. I wanna see hoq thw hobbywing preforms

I'd really like to see a video over driving these escs with higher kv motors run like a strong lower pitch prop on 2300kv maybe even a 2450kv on 6s to actually push the ESCs before they desync or whatever, maybe even using a 3000kv 2004 motor with a 3.5" prop on 20mm escs. I'm not so much concerned about 5" drones, but getting max performance for smaller light weight drones since RID had kind of forced us to look at smaller drones more

FETTEC ESC is still worthy?

What was the PWM frequency of Speedybee running Bluejay?

12:50 I can second that, the ESC are operating at a pretty ideal point. They basically just switch between motor phases, there is not much loss here. However switching at a wrong or non ideal position will result in a less efficient motor, not necessarily a less efficient ESC. It's not unusual to have an ESC to be more than 95% efficient. The only major efficiency loss is because of the forward voltage drop because of Rds(on) of the FET.

Hi, which AM32 firmware did you use for testing?

Danke!

7:08 This efficiency graph looks a bit to jaggy, are you sure the measurement readings are synchronised? I've had similar things happen when the measurements weren't synchronised. Constantly auto-ranging measurement equipment could be the problem too. But it looks like you are using RCbenchmark, in my experience, that should get you good measurements.

How much is component choice and how much is firmware? Change only one variable at a time, hardware or software - not both. Also the KV setting in AM32 should allow more acceleration.

In my opinion testing different ESC's with different firmware's doesn't make much sense if you label them by FW type. First of all, everyone is labeling A ratings without a common rules. I believe that ESC's layout, stack up and component selection plays a much bigger role in the performance then the FW it runs. I would like to see first a test of current draw capabilities for continuous A vs some reasonable operating temperature. And only then label them by your own standard and compere the performance. Would be interesting to see the BL32 ESC tested before and after reflashing to AM32 FW.

i got 122 mph on a azure power 5048 with supernova motors. ALSO with real flight I noticed a MAJOR difference on my Speedybee bluejay and blheli the bluejay sagged the battery faster and not hitting top speed and the blheli went super fast BTW speedybee f405 stack has that nice esc for 70$

i always set my rpm frequency setting 16-128k much better results then when just in byrpm

atm price dictates what i buy. speedybee is killing it with their prices, besides they end up destroyed. And ty for throwing in skystars, another brand i can just afford lol.

Please test the ESCs for desyncs, I have been getting desyncs because of high KV (1950kv F60IV) motors, I tried Mamba F40, F50, F55, AIRBOT Furling32 (even got them smoked just from giving a throttle), I tried Oscar Liang's recommendations with a bunch of different rampup power and demag comp-s settings, changed all set of the motors, nothing ever helped, always got the desyncs until I tried a high end expensive ECS which I won't name because this is not an advertisement. I am really curious what other ECS-s can avoid desyncs on such a high KV. The main scenario how I got the desyncs was - I gave a full throttle for 1-2 seconds, then throttle to 0, and immediately Roll to the side on 1100deg/s rate. At the end of the roll I have been getting the desyncs. I think because of back EMF and from cutting the throttle from 100 to 0 and from acceleration of motors to stop the roll.

The torque-speed and acceleration results need digging into... Given torque = inertia * acceleration, there is a major inconsistency in the BL_HELI32 firmware achieving the lowest torque AND highest acceleration. Is the interruption in measurement data with BL_HELI32 fw causing a false acceleration measurement?

Analytics!

🍿🍿🥤🥤

Should probably point out from the data. That Blheli-32 using by rpm also decreases motor acceleration performance. Not a feature I want when flying freestyle. Best to keep parameters from its lowest PWM to its highest right PWM NOT including by rpm.

Now that you got us the beastiest beast of a motor you gotta figure out which ESC and Prop can actually handle that power xD I really would like to see how the foxeer ESCs score in these tests as these are the ESCs racers use for their reliability in frequent turtles and MCK also says it's the ones least prone to demag. I also found that bluejay is super chill on defaults, especially with noisier builds while BLHeli32 is much more prone to oscilations or other issues. Might that actually be the double acceleration-performance transforming that noise much more effectively into prop movement?

bl32 delivers less torque but accelerates faster?? how can that be?? it is the torque that accelerates a given mass .. not??

The diatone mamba f60 pro with AM32 does not exist

With the huge difference in responsiveness with BLHeli-32 vs BLHeli-S/BlueJay, how is it that in the real world, these two are used pretty much interchangeably with no real need to retune? Folks that want to save some money just buy BLHeli-S ESCs and there doesn't seem to be any huge consequence to that.

First

..... this is one of the least scientific tests I've ever seen. The control is nonexistent, and the conclusion is inconclusive because of that. The pro 3 esc has better microprocessors than most. All this really proved was that faster microprocessors are better than slower ones 😂. Go figure.

I would love to see how ESCape32 works on those am32 escs. I had very good results with it