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First heli! Trex 450

PsyBorg

Wake up! Time to fly!
#41
That sounded like a pretty windy day for a first flight. You are a very brave soul. Congratz on a great start. You did an excellent job on the set up to be that smooth first flight. :applause: Little more expo will calm the nerves a bit as you can always dial it back later.
 

Fluburtur

Cardboard Boy
#42
Wasn't that windy actually, almost nothing.
The integrated mirophone of my camera makes it sound very bad so I will probably use my external mic next time.
Also controls weren't too bad, I did use like a whole 5mm of the stick movement but im used to fairly touchy planes anyways so it wasn't bad.
I will try lowering the headspeed a bit too. Too bad I don't have a lipo alarm to tell me when the battery is getting low, the ESC does have a soft cutoff thing but I don't want to rely on that.
 

PsyBorg

Wake up! Time to fly!
#43
You use a Taranis correct? If so keep track of what voltages your battery comes down on and start using the % timer function. That works out to be pretty darn accurate when flying slow or flying hard with my quads. I got mine set so the batteries are pretty much at 3.8v per cell when they go back on the charger no matter what I do to them using that timer.
 

PsyBorg

Wake up! Time to fly!
#45
I would look in the instructions / pdf and see if you can use % timers.

Battery alarms are annoying and very unreliable to be honest. They will constantly be giving false alarms specially with high current draw applications and a battery that will sag. They also do not account for how hard you are using the batteries. More then likely you will be flying idle up mode so your draws will be reasonably steady in a heli. Just be wary of the draw backs of using a battery alarm in the early part of their use. I used one in the early stages of my flying and learned how unreliable that method can be depending on many factors. Killed several batteries and puffed several others using them. Other times I would get back inside to charge batteries to find they were still over 4v per cell.
 

Fluburtur

Cardboard Boy
#46
The flysky doesn't have a timer sadly, also on my lipo alarm I can set the voltage per cell at which it triggers, so I could easily take into account voltage sag by doing some simple math.
Anyways I will be running both a timer and the alarm until I knows exactly how much time I can fly
 

F106DeltaDart

Well-known member
#47
Sounds like a good plan. I flew off of my watch timer until 2 years and it was fine. You just have to double check that you remember to hit the start button :p. I've done that a few times, but always caught it before there is an issue.
 

Fluburtur

Cardboard Boy
#48
I went to do some more flying today, there was a bit more wind so I just tried to keep it hovering but I ran in some sort of issue.
Sometimes during the flight I get some sort of fairly violent jerk movement just like someone suddenly hit the stick (im pretty sure I didn't do that)
Hopefuly I managed to recover every time but I don't know what caused that.


You can see that at 38 seconds, I landed to check stuff and flew again and it did a similar thing.
Actually yesterday it did that too, acted like it put the collective at 0 for like half a second.
 

F106DeltaDart

Well-known member
#49
I went to do some more flying today, there was a bit more wind so I just tried to keep it hovering but I ran in some sort of issue.
Sometimes during the flight I get some sort of fairly violent jerk movement just like someone suddenly hit the stick (im pretty sure I didn't do that)
Hopefuly I managed to recover every time but I don't know what caused that.


You can see that at 38 seconds, I landed to check stuff and flew again and it did a similar thing.
Actually yesterday it did that too, acted like it put the collective at 0 for like half a second.
That is concerning.. I haven't had anything like that happen, except maybe if you got a really nasty gust. Might just want to double check all of your wiring connections for security. Next try a range test with a friend holding it at different orientations (blades removed). Since most of the heli is carbon, it is easy to get signal blockage. If nothing is found there, maybe try letting it sit on the ground (throttle cut engaged) and walking around and moving the controls for a few minutes and see if you can see the swash jump like that.
 

Fluburtur

Cardboard Boy
#50
I put one of the receiver antennas on one of the legs (those are plastic) and the other at the bottom of on of the boom support rods.
There wasn't any particular gust of wind then either. I will do the checks tomorrow, might also post that on the vstabi forum.
 

PsyBorg

Wake up! Time to fly!
#51
The mechanical's sound smooth so I don't think it is something worked loose. No crunching or grinding prior to or after that pitch forward. The motor rpm seemed steady as well. I would check wire connections for pitch, check the servo gearing, check the control horn just to make sure though. I would also check to see if your gyro can move at all as well as the connections for that.

I don't think it was a fail safe. Could have been a brown out but that usually effects all axis. Maybe put the pitch servo on a tester and do that continuous cycle test for a good five minutes to see if it stalls or gets spastic at any point.
 

Fluburtur

Cardboard Boy
#52
I checked all the mechanical stuff and it is good, also everything is plugged right.
I went to do some more flying today, there was too much wind so I didn't fly the heli much but I got the problem again.


It can't be a radio glitch because im like 5 meters away and those receivers can do at least 2km so I guess it's somehow the gyro acting weird because of the wind or the servo, I didn't test it yet but I think I will make some arduino servo tester that moves the servo back and forth forever.
 

PsyBorg

Wake up! Time to fly!
#53
Ohh mate don't ever think it can't possibly be the radio. NEVER say never. There is a spot out back where I fly that no matter what radio system or power or antennas or antenna orientation I use if I cross into it my quads fall from the sky like bricks. There are several spots out on Furey Field that when crossed will drop a craft like a rock. I see a radio tower in the background. If that sends out a random or sync pulse it could easily inject or defeat the signals between your radio and the heli.

Read up on wave propagation and reflections in your spare time. You could even knock yourself out of the air if you are close to a reflective surface and bounce a signal just right and cancel your self out.

Listening to your set up it sounds too smooth to be mechanical and I am now wondering since you had a very different reaction this time if that training gear is not resonating and randomly syncing the legs to produce a large spike that effects the gyro. I remember seeing that very jump with my big nitro when I had the wooden dowel / wiffle ball training gear in it
 

Fluburtur

Cardboard Boy
#54
Well one leg of the gear is actually vibrating while in flight, also I posted about that in the vstabi forum and they asked me to send the data log which I will probably do tomorrow because I need to go to bed.

Also I often fly in that area and never had a radio problem so I highly doubt it's the radio tower, I even flow right under bigger ones sometimes. It is probably a cellphone tower and those operate at 900mhz so no harmonics near 2.4ghz.

Also I set the gyro to be very easy to fly so I guess it will smooth out any hard move from the radio but I need to test that.

Now that I think about it I should probably get a spectrum analyser.
 

Fluburtur

Cardboard Boy
#55
Someone wanted to get a clip of the sound of my heli running so I quickly flew it in the garden.


I was mostly trying to keep it in the frame there, this time it didn't do the weird thing but you can see the training gear vibrating a lot.
 

PsyBorg

Wake up! Time to fly!
#56
That training gear shake to me seems like it it due to rudder oscillation as it is all side to side. Might check into gyro sensitivity and see if you can tweak that out. Mechanical's still sound smooth and steady. Maybe a slight gear mesh chirp so keep an eye on the motor screws and how that gear meshes. That usually has a tendency to "walk" a bit over time.