first flight-tried to hover,it did for less than a minute,started to come down fast,i hit the throttle-did not help,landed hard and flipped when i tried to shut it down-no damage,my question is why-i attached log.
yep-fresh off the charger.
Hi nwillitts,
Hope you didn’t have any damage resulting from your crash. Upon first look at your log file, everything seems OK. Your battery voltage and board voltage all look good and the RCIN and RCOUT seem to track appropriately.
You take off in Altitude Hold, change to Loiter and then change back to Altitude Hold. Your whole flight seems to have taken place between 3-4 meters in altitude from beginning to end. The only curious thing is that you ended up at an altitude about 3 meters lower than where you took off. Does that make sense based on your flight?
When you say “it started to come down fast”, what altitude were you at and what % of throttle did you try to apply?
What kind of experience if any do you have flying multirotor aircraft? If you have lot’s of experience I apologize in advance, I’m just trying to get a picture of what might be involved. I would recommend you try again and stay in Altitude Hold for the whole flight. Did it change altitude quickly after switching from Loiter back to Altitude Hold mode? I saw this note in the Operators Manual:
[quote]To avoid sudden changes in altitude, set the throttle stick
to center position before switching modes, including in the
event of a GPS failsafe[/quote]
Never having flown an Iris + before it’s hard to say, but it looks like you climbed with a higher throttle input for about 1.5m and then dropped rapidly again for about 1m before adding more throttle. Maybe you just needed a bit more altitude.
Let us know what happens, and good luck!
when it started coming down it was maybe 12 feet high,i punched the accel to try to stop it-it seemed to help-then nothing,so i managed to get it to land a bit hard,did the motor cutoff and it flipped.
i have been flying all sorts of aircraft for years,this is my 4th quad-first iris product.
i am a bit shy to fly it now.seems so unstable.
i don’t understand why the difference in take off and landing heights.
Take a look at the graph attached.
[attachment=0]Graph.png[/attachment]
Your throttle out max maxes out (see red boxes) even though throttle-in is only around 45-50% (I don’t see the ‘throttle punch’ you talk about)
Again, the focus is the Throttle Out maxing out quite early and then happening more frequently. Which would indicate that did not have enough thrust. Which would means mechanical failure (motor or loose prop maybe?)
If I graph RCOUT of ch1-4 it is channel 1 that maxes out which would indicate a problem with thrust on that motor.
[attachment=1]MotorMax1.png[/attachment]
I agree, did you remove all the Christmas rapping before you tried to fly it. Did you at least take it out of the box first. Based on your location it should be freezing out with snow on the ground. The copter thinks its in Pam Springs.
Mike
I had a look at the log, and it definitely looks a mechanical problem, such as props not tightened, or something. There was no “hit the throttle”. Throttle never goes above 60%, and during the worst of it it’s not above 50%.
The autopilot does use full throttle to try and maintain altitude, but this doesn’t work. At the same time, the stabilization isn’t working well. This also tells me something was going on mechanically. Probably Ch1 as Bill suggests.
interesting.
the thing is i hit the throttle full open and there was very little response.
i have had this for 2 weeks-i studied everything and calibrated it several times just to understand and to be sure it was right.saved flying it till Christmas day.
this aint my first quad.
what gets me is first this happens then minimosd takes a dump.
looks like i got some lemons i guess. 
and yes ,props tight using supplied tool.
[quote=“iseries”]I agree, did you remove all the Christmas rapping before you tried to fly it. Did you at least take it out of the box first. Based on your location it should be freezing out with snow on the ground. The copter thinks its in Pam Springs.
Mike[/quote]
i am in s.w Virginia at the moment,unusually warm here at the moment.i live in NOVA-northern virgina.
what makes you say the copter thinks its somewhere else?
Guess I should lay off the Egg Nog next time I look at someones log files! 
I don’t know how I missed that one it’s clear as day, at first I thought I must have been looking at the wrong log file, but I went back and checked and sure enough there it was!
@Bill, What program do you use to graph the logs?
ok,tried to fly again.
this time i slowly brought up the accel,got to halfway,pushed past that a little and then i see it,looking at the front of iris the left motor starts to oscillate,as if power was rapidly turning off on repeatedly,leg started vibrating.throttle response at this point was sluggish. needless to say i shut it down.
log attached.
thank you all.
i just realized i recorded the whole thing-and no the prop was not the problem.
[youtube]https://www.youtube.com/watch?v=twd1w0bYcNo&feature=youtu.be[/youtube]
wont embed.
direct link youtube.com/watch?v=twd1w0b … e=youtu.be
It could be a bad connection to the motor from the esc, or from the Pixhawk to esc.
[quote=“nwillitts”]i just realized i recorded the whole thing-and no the prop was not the problem.
[youtube]https://www.youtube.com/watch?v=twd1w0bYcNo&feature=youtu.be[/youtube]
wont embed.
direct link youtube.com/watch?v=twd1w0b … e=youtu.be[/quote]
Man that’s painful. I couldn’t even listen past 1 minute. Sounds like one of the motors is emitting a lower frequency sound i.e. not reaching the correct speed, and then when you throttle up it sounds like it backs off and throttles up rapidly at around 10 to 20hz. As a layman I’d guess it’s a shot motor.
Regards,
Mark.
I’m curious about a few things
i have had this for 2 weeks-i studied everything and calibrated it several times just to understand and to be sure it was right.saved flying it till Christmas day.
That is a bit odd since Iris is ready to fly and all of the calibrations are made at the factory and the vehicle is test flown as well. What all did you calibrate?
what gets me is first this happens then minimosd takes a dump.
viewtopic.php?f=48&t=10759&start=0
You must have disassembled the Iris to add the MinimOSD. What else did you add or modify on the vehicle?
[quote=“Craig3DR”]I’m curious about a few things
i have had this for 2 weeks-i studied everything and calibrated it several times just to understand and to be sure it was right.saved flying it till Christmas day.
That is a bit odd since Iris is ready to fly and all of the calibrations are made at the factory and the vehicle is test flown as well. What all did you calibrate?
what gets me is first this happens then minimosd takes a dump.
viewtopic.php?f=48&t=10759&start=0
You must have disassembled the Iris to add the MinimOSD. What else did you add or modify on the vehicle?[/quote]
just the osd-externally mounted FPV tx.
anyone look at log when motor was doing that so i can have an idea what to look for?
still sits…staring at me…
[quote=“nwillitts”][quote=“Craig3DR”]I’m curious about a few things
i have had this for 2 weeks-i studied everything and calibrated it several times just to understand and to be sure it was right.saved flying it till Christmas day.
That is a bit odd since Iris is ready to fly and all of the calibrations are made at the factory and the vehicle is test flown as well. What all did you calibrate?
what gets me is first this happens then minimosd takes a dump.
viewtopic.php?f=48&t=10759&start=0
You must have disassembled the Iris to add the MinimOSD. What else did you add or modify on the vehicle?[/quote]
just the osd-externally mounted FPV tx.[/quote]
i calibrated the compass.
several times.
is that a problem?
I don’t believe you did anything wrong. One of the problems with Copters is that the controller has no idea what the motors are actually doing. It tells the ESC’s to spin the motors at a desired speed and hopes they do that.
In your case with a bad wire going to the motor or bad winding in the motor it does not respond correctly causing the controller to try and correct for it.
Since you purchased a ready to fly and it was tested at the factory one can only speculate that something happened in shipping and handling that caused something to come loose. That should not happen.
Mike