EMAX Nighthawk Pro 280 ARF

[jhitesma]

Yep, connectors and antennas look right!

I know all about those windy days. We don't get rain much here in the desert but it's rare for me to get calm winds. My only FPV flights with this thing so far were in 20mph winds at the calmest and it just messed me up too much to have to be tilted that far over to hover And when I crash it means cleaning sand out of motors. Waiting on my co-worker to respond to my text right now....sure hope he responds so I'll have a spotter - then I can risk flying at a park where there's actually grass (even if it's still sand under the grass!)

That said my primary flying season is just starting. Today is the first day it hasn't been predicted to go over 100F (other than days when rain cooled things down) and the next two weeks of predictions are all in the upper 80's or mid 90's finally! More than once I've thought about using my LRS setup on a relay so I can put it on top of my truck but fly with my TX in the cab with the AC on

Glad to hear a different channel helped. I'd still suggest looking into a better camera. The CMOS camera this quad comes with tends to cause some jello and it's really not good at handling higher contrast lighting. A good Sony CCD camera isn't that expensive anymore and really improves the image quality. But at least you're able to get out far enough to start doing more flying now!

 

[jhitesma]

Woo Hoo! After getting frustrated with my tri my co-worker finally responded this morning and was up for some flying. We loaded up my FT mini scout, the twitchity hex and the Nighthawk 280 and headed out to do some flying.

Tried flying the Scout with the TX from my Nano3D. It worked...but could have really benefited from some expo, was much harder to fly with that than with my 9x. We still had a bit of fun with it and I was starting to think I may get to chase it FPV from the hex or quad...but then a crash took out the firewall Oh well. Easy repair but didn't have a glue gun in the field so couldn't do it there.

So I fired up the hex. FPV system was working well but I figured I'd do a LOS flight first since I haven't flown in in awhile. Glad I did. Something was not right today. I had taken the RX off it for the Nighthawk so I took a new RX I built for the tri and put it on the hex this morning. First flight hex felt good in acro...switched to horizon and something just felt wrong. Then all of a sudden with no stick input it did 3 or 4 TIGHT rolls and slammed into the ground. No clue what caused it but the camera wasn't responding after that - just a black screen - so I cut power to the VTX and flew it LOS instead. But it still just felt off. At one point I thought I was going to loose it because it seemed to stop responding. Was not acting like itself at all. So shelved it for the day.

Finally we got the Nighthawk out and it saved our morning. I flew half a pack FPV and finally started to get a good feel for it in the air. Had a few crashes trying to fly around some small trees at the park - but never even broke a prop (DAL 6040's right now) and most crashes I even landed right side up so I was able to just re-arm and take back off. Fun! Then passed it to my co-worker who did a quick LOS flight to get the feel for it and then he went under the goggles to fly half a pack. He really liked the FPV flying and said he found it much easier than LOS since he didn't have orientation issues.

I was really glad we finally got to have him try it. He's flown a few of my other quads LOS just a little bit but that's it for his experience so he's basically a pure beginner. I put him on the stock tune with the stock rates, gave him horizon mode at his request and then let him go. After just a minute or two to get used to the throttle he was trying to fly around the trees as well

Unfortunately we forgot that I didn't have a beeper on it yet and drained one of my new Tattu packs down to 2.87 on one cell...oops. Not what I wanted to do on the 3rd flight on an expensive pack!

Next I gave it a go FPV and finally did my first flips through the goggles. Was a blast and not nearly as disorientating as I expected it to be. Still not happy with the tune, but it's definitely flyable.

The only other people at the park were a step-father and son who were playing disc golf. After they finished their round they came by and I offered to take them for some flights in the goggles. I did some crazy flips and rolls which the son loved - I even did a yawing flip which he thought was fantastic The step-father wasn't as big on the flips and rolls (I didn't warn him before the first one!) but he still loved it. He sounded pretty interested in getting a quad himself but was more interested in the sound of the versa copters than the Nighthawk because he's a man and knows that building is half the fun I told him about flite test and he thought he may have seen some of the videos already so I wouldn't be surprised if he turns up here soon

I didn't tempt fate and try turning on the mobius today...maybe that's why we had the best luck yet with FPV on the 280 So, sorry no video today.

But we had more crashes on the 280 than I could count and didn't break anything. Even the DAL props took the abuse (including a couple of good cartwheels) and other than a few chips look no worse for the wear.

Definitely helped rebuild my confidence. I was really starting to think I had lost the ability to fly FPV after my last few times out.

Not to find out why the hex was misbehaving today...and recharge my packs so I can give the nighthawk another go tomorrow

 

[jhitesma]

Yeah...Draining 1480mah from a 1300 pack on it's third use isn't how I usually treat nice packs.

Gotta admit though, the Tattu seems to have handled it just fine...not even a tiny bit puffy. We'll have to see how it does long term now...

 

[Gorsky]

I'm glad to read that your 280 is able to withstand all that abuse.
Mine should last me a while then !

 

[Ocean]

Yeah...Draining 1480mah from a 1300 pack on it's third use isn't how I usually treat nice packs.

Is that even possible?

 

[jhitesma]

Is that even possible?

I should have taken a photo of my charger to prove it is

It's only really possible on a high quality pack - but it's still highly inadvisable. The thing is the ratings on packs aren't 100% precise due to all kinds of variables that can't be completely controlled. So a 1300mah pack it's only really rated for 1300mah of discharge. On cheaper packs the actual capacity may be very close to 1300mah so it's best to only fly to 80% of that 1300mah. On more expensive packs they fudge the other way and it's usually safer to use the full 1300 and you may get away with discharging a bit more.

But going that far over is never a good idea and not something I meant to do. Just got lost in the moment, forgot I didn't have a beeper on the quad and stupidly ignored the timer on my TX beeping at me (assuming it was just a low voltage warning from my TX which I have set VERY conservatively but my TX pack is on it's last legs so it tends to go off at inopportune moments.)

Like I said, one cell was showing <3v even after resting which is never good. <3.3 is bad. I was kind of surprised my charger even let me charge it at <3v. The other two were <3.3 as well but still over 3.

I've had packs I only drained to about 3.5v that puffed so for this one to go that crazy low and still be rock hard I'm pretty impressed. Though I will admit it's not quite as hard as it's twin so there is a little bit of puffiness...but still not anything I'd call "puffy".

The other pack I drained to about 3.7v (after resting) and it only sucked down just over 1000mah when I recharged it. So the 1300mah rating on these tattu packs is actually pretty conservative I'd say. Other less scrupulous manufacturers would probably try to pass them off as 1400's. Hope I can come up with the funds to pick a few more of them up from MRSS before they run out or end their sale, at <$18 they're a steal!

 

[Mach60]

Modes on 280

Hi guys. I just finished setting up my 280 and I am using a Spektrum DX6i trans. I don't have any three position switches an it appears that the Gear switch is the only one that I can program for the modes. I added the Horizon mode to the gear switch when its flipped to 1 from 0. I have confirmed the red light comes on and the 280 seems to self right when I let go of the sticks. My question is, what is the default mode? Is it acro? Then, I flip the switch and it Horizon. So, I can't get Angle on this trans, is that right? Any suggestions?

 

[jhitesma]

The default mode is acro.

You could setup a separate switch to enable angle mode if you have one. But I'm not sure what would happen if you flipped them both at once telling it to go into angle and horizon mode at the same time.

But if you only have one two position switch then you can only pick two modes. You could set it up to be horizon when the switch is low and angle when it's high.

Just how you'd do that is slightly different depending on whether you're using the stock baseflight install or if you've flashed over to cleanflight.

 

[Mach60]

Thanks jhitesma. I think I had it programmed that way once during the set up, but changed my mind. I guess I could do that and as I get better, I could remove angle mode and just go back to acro/horizon. Thanks for your help!

 

[Mach60]

I just gave it a try and it works. Now, I have angle mode on the aux 1 at the 0 spot and horizon at the 1 spot. (same switch).

I am using cleanflight for the config.

The red light on the 280 blinks once when I flip the switch but is always on now otherwise. I will run it this way for a while and see what happens. Thanks again.

 

[jhitesma]

Glad to hear you got it working! The light is red in either angle or horizon mode so that's why you just see it blink when switching.

Honestly I'd suggest running acro/horizon. Acro is just too limiting and too different from the other modes and will really only hold you back i the long run.

That's the voice of experience speaking by the way I used angle way too much on my first build and then started using Horizon when I wanted to learn to flip and roll. The transition from angle to horizon wasn't horrible but did take some getting used to. But acro is really where it's at and WELL worth the effort to learn. It's frustrating at first...but once it clicks suddenly it's so much easier. Now I usually don't even bother to setup modes and if I do I just put horizon on a momentary switch so I can toggle it for a few seconds if I get into trouble. The 280 flies so well though that even on the stock setup (which is just stock baseflight defaults) it will hover hands off (in calm conditions) in acro mode once you level it out.

I have a hard time flying angle now because it's such a different way of thinking.

Essentially the difference is that acro is a rate mode - which means the position of the sticks sets the rate of change in angle. The further you move the stick the bigger that rate of change gets - but as long as you hold the stick anywhere other than center the quad will keep rotating in that direction. Move it a little and it will slowly tilt in that direction, move it a lot and it will quickly tilt in that direction. With angle mode the sticks set the angle of the quad. So you have to move the stick and hold it in a position for the quad to stay at that tilt, let go of the stick and the quad will loose it's tilt, plus there's a hard limit on how far the quad can tilt so no flips or acrobatics. It's kind of the opposite of flying in acro mode in a lot of ways. Horizon is a hybrid mode. Small stick movements work like angle mode - but large stick movements work like acro. It's easier to start flying in and learn flips/rolls with since it will level you out after if you just let go of the sticks. But once you really learn acro horizon is kind of frustrating because it's a mix of flying styles so it's actually kind of more complex than either acro or angle.

I justified learning with angle then horizon because my first build was a FT Knuckle with bluewonder motors - so even fairly mild crashes usually meant fairly serious repairs. I still have a pile of motors with bent shafts or broken windings, and enough broken wood booms to make a small campfire

On something like the nighthawk though the biggest risk is breaking props. So I say toss some 5045 DAL's on there and crash the heck out of it until acro clicks. Then step up to the 6040 DAL props until you're feeling good...and finally get some HQ 6045's and go tear things up

 

[Mach60]

Great information!! I took it out tonight and just practiced hovering and then practiced landing on spots on the driveway. I broke two props, but on the same crash. I took it up too high and hit a tree branch and she fell out of the sky. I burnt through 3 2200's and only had the one serious crash. I am going to take your advice and remove angle mode. I really didn't see much difference tonight, just hovering around.

I looked at starting with a FT quad but thought I would be replacing wooden booms all the time. I read a lot of information about the 280 and decided this was the one for me. I enjoyed watching your videos and value your thoughts and opinions. Thanks again for the help!

 

[Mach60]

Receiver Blues

Ok, I bought an Orange R615X so I could run CPPM on my NightHawk. It came in the mail today and I took out the standard old DX receiver I had in it. I set it up in Cleanflight as a PPM, saved and rebooted. Then I plugged it in, bound it to my DX6i, then I checked the receiver tab. everything except the throttle was backwards...no big deal, I just reversed them on the trans. I noticed that all the levels where way off. sitting at the mid point, they were at 1350 or so and when I moved the ailerons all the way left, the level dropped all the way and then bounced back to 1500. The same thing happened on all the channels except the throttle. When I did a motor test, only motor 3 started then the others came to life as I gave it more but then they wound down and stopped while 3 kept running. I re-calibrated my ESC's and tried again with the same situation. when I use the slider, they all run at the same speed. So, I put the old receiver back on and reset Cleanflight with my old RX and everything works fine. Do I have to re-flash the board when I change a receiver? Have you every heard of such craziness?

 

[jhitesma]

Glad to hear my posts and videos have been helpful for you!

I haven't used the Orange RX's and don't have a Spektrum TX so I can't give too much specific help...but I can give some general assistance.

It's not unusual to have the channel values shift when changing from a PWM RX to a PPM RX. The RX itself may be handling values a little differently and PPM is decoded differently than PWM.

So you'll probably have to re-adjust the subtrims and endpoints on your TX to work well with the PPM RX just like you had to reverse the channels. Basically use the subtrims in the TX to bring all of the channels back to 1500 center then adjust the endpoints to bring them to 1000 on the low side and 2000 on the high side. The other way would be to change the settings on the FC to match your TX - you could change the midrc value to 1350 to match what you're seeing from your TX and then adjust your endpoints to 1000-2000...but that would give you a somewhat skewed scale so it would be best to get your TX setup so it's midpoints are at 1500 with the PPM RX.

You shouldn't have to recal the ESC's since the FC actually outputs the values to them - as long as you don't change the minthrottle/maxthrottle settings on the FC the values output to the ESC's will be the same regardless of what your TX is sending.

 

[Mach60]

Thanks again for your help. I am going to leave the old one in it for now while I practice. I just don't get why the motors don't spin up at the same time when I test it on the trans. I am going to put some props on and go practice.

 

[indy6]

Hi jhitesma,
You've done an amazing work! Not sure I understood everything right being a tourist....
Anyways, I've got the RTF version and well yes it's heavy, but so far it's very powerful to me...
One of your cons was the PID settings. I flashed Cleanflight and so far so good. Doing some flips and stuff... then tried different PID modes and the quad start wobbling like crazy... and I crashed.
Anyways, would you mind to share your PID settings? I hope I didn't miss that in your huge blog and forum,
Thanks for your work...
Regards,

 

[jhitesma]

To be honest, while I'm not happy the the stock default baseflight PID's...I've yet to tune them any better.

I was instead curious to see how far I could push it bone stock. I do plan on doing some tuning and putting CF (or Boris's version) and even Tau on it at some point...but that will be happening later this winter. The past few weeks I've been really busy waking my yard up from summer hibernation and getting our new garden in so I haven't had any time for my hobbies. This next weekend I have to finish some Halloween projects, then the weekend after is Halloween...so most likely won't be until November that I have a chance to do much more with it.

Plus I'm still trying to get my pesky tri in the air as well

I know twodogrc has posted some PID's for CF with pid controller 2 over on rcgroups.com if you're looking for a good starting point with CF.

Strong wobbles like that would generally indicate your P and possibly I terms are too high. So dropping those would be a good idea if you don't go with someone elses suggested PID's.

 

[jhitesma]

Ok. People keep asking me about PID's for the Nighthawk. I've been lazy and just seeing how far I can push the stock default baseflight PID's so far. But now that the weather is getting nicer I'm ready to do more flying and ready to get this guy dialed in better.

So this morning I decided to try and do a PID tuning video. Before I even got outside though I was checking the calendar to make sure it wasn't really Monday because just about everything that could go wrong was going wrong :black_eyed: I usually like to tune using my phone and EzGUI - but my phone is now over a year past when I was due for a replacement and about a month ago the USB port started acting up...it will only charge off of 1 of the half dozen USB cords I have piled up on our kitchen counter. And sure enough my USB-OTG cable no longer registers on it Went to try my tablet instead...battery was dead. Went to try my daughters tablet....battery was dead. Tried my previous phone even though it's so slow it drives me crazy...yep battery was dead. Arrgh.

Ok, I've got my ancient notebook. It's slow but it works and has been plugged in so it's charged. It's battery doesn't last very long but it lasts long enough to get through the two packs I have charged up to tune with. So I settle for it. But it's screen even on it's highest brightness setting is really dim.

All the same I put on my hatcam, got my TX and the 280, dragged it all out into the backyard and filmed about 35 minutes or so of tuning with commentary. Unfortunately that ancient notebook screen didn't come across AT ALL in the video. I anticipated that so I tried to read out values as I modified them...but it's still not the quality of video I had been hoping to achieve. And the "best" part of the tuning where I took the I and D down to 0 didn't make it into the video because I forgot to hit record :black_eyed: Well, Sunday does rhyme with Monday I guess and they're right next to each other....

Who knows when I'll have time to try and reshoot a better version. Could be a month or more.

So I'm wondering. Would anyone be interested in seeing it? I only tuned for two packs and it's by no means a fully optimized tune. I'm liking it better than the stock defaults...but it's going to be another 2-4 packs before it's getting dialed in.

What do you guys say? Should I upload what I've got...or hold off until I can get some better video and a better tune?

 

[jhitesma]

Well, someone on rcgroups beat me to it and got BLheli 14 flashed to this guy. I'm a little disappointed I didn't get to be the first...but at the same time I'm glad I didn't have to risk my board before anyone else

But with facebook reminding me that yesterday was the 2nd anniversary of the night I first hooked an arduino to my wii controller and confirmed I could get MW running on a homemade flight controller I felt like I had to get back to my roots and melt some solder, flash some firmware and do something few others have so far and join in on this fun.

I had planned to add a single 6 pin header so I could use blheli's multi ESC setup to flash all four at once, but turns out I'm out of 6 pin sockets so I did the same thing Marco67 on RCGroups did and added a 3 wire servo connection for each one:

First connection


All four.


The wiring is pretty simple. All four ESC's have a small 4 pad programming header. They're all oriented differently but follow the same convention with GND closest to the outside of the board, then 3.3V, then C2CK and finally C2D closest to the inside of the board. I wired them with orange to C2D red to C2CK and brown to GND. 3 of the ESC's I used the GND pad on the programming header, but on one where the GND pad was really tricky to get to I just grabbed GND off a nearby connector.

I then whipped up a current limiter from an automotive lightbulb. So far I've lived on the wild side and gone without...but with a full $60 board at risk I decided it was time to be smart and make it happen.

I haven't made up a harness to flash all four ESC's at once yet...but I did get all four to flash and they're working!

The setup - Arduino Mega flashed as 4 in one programmer, board, current limiter, battery:


It survived! That's not the current limiter bulb lighting up, it's just the reflection of my camera flash



Should have video of the process later this weekend. Didn't come out quite as well as I had hoped...but hopefully it will enough to convince some other people they can tackle this as well!

 

[jhitesma]

Wrote up a FT Article on flashing BlHeli to this beast but still waiting on it to get approved.

In the meantime here's the videos of the process.

First make yourself a current limiter if you don't already have one. This really is a must on this since if one ESC's has a problem the whole board is trash:

Next Wire up the connectors like in my photos above. Here's a "Let's solder" of me doing it. Sorry the camera angle isn't better. If you can handle 40 minutes of listening to me describe what I'm doing you may enjoy it If not at least the first 5-10 minutes show how to get the board off and I give some tips throughout on how to make it easier on yourself than it was for me:

Here's the pinouts to go with that:


Then once you have ports it's a simple matter of flashing like any other SiLabs ESC:

Finally go test fly! I grabbed the first pack within reach which was only at about 80% so I didn't get a very long test flight. But it did well. Felt a little bit better so with some work on the tune I expect good things. This is still baseflight and the tune I was working on last week:

And I went ahead and posted the videos of that tuning session last week even though I'm not very happy with how they came out and the tune was just a preliminary tune starting to get into the ballpark...I'd include them here but I've hit my video limit for this post and don't want to bother with another - so just check out my youtube channel if you really want to watch almost 40 minutes of me yapping and tuning