hiaber

After years of waiting, i finally found my way to affording a DF Vti pro. got it on the 27th of december, and have had the regular bumps and bruises to be expected by any new DF flyer.

after learning to fly half decent with the Ti off, i tried to get it working. i could only get one light, and decided, oh well, i'll try another time. that same flight, i crashed gooood. - landed upside down. it bent the upright main board, and the Ti sensor board. i bent them back into place nice and gently - still couldn't get 2 "eyes" lit. Today i noticed that one of the sensors had de-soldered itself from the board, re-soldered it. STILL CAN'T GET MORE THAN ONE LED LIT! - with one exception... if i take my soldering iron and with the DF sitting on my bench, circle it around the sensors at about 6-8 inches away, it will pick up that kind of heat signature, but it takes me putting my finger right up close to the sensor for it to register my body heat. Also - the sensor closest to the power switch is substantially more sensitive than the other sensors - it will register my hand at about 4-5 inches, whereas the other sensors i almost have to be touching them.

Is this normal, is something screwy with my board, any tips tricks or suggestions? Gonna call DF tomorrow, but thought i'd try and get this off my chest through other channels as well.

Cheers,
JHB

draganfly.com

My Feedback: (40)

JHB, I do recommend calling in. You'll probably want to speak with Jeremy.

-Adam

hiaber

Thanks Adam. I did call in and talk to Jeremy. Just for anyone having these same questions, the answers i got were - it is normal for one sensor to pick up heat, not unusual that the others won't sense heat unless you have your hand or finger really close, and the reason i couldn't get 2 lights is due to the cloudy sky and the wet grass. He said that One light will give me some stabilization, naturally 2 are better!

Cheers.
JHB

vi360

Thanks, this is all good to know.

TheHindmost

[/quote]

Did he say why it's normal for one sensor to pick up heat more easily than the others? Also, how were you deciding that a sensor was "registering heat"?

Just curious...

Thanks,

Will

hiaber

He did not say why its normal, and i was deciding that the sensor was "registering heat" because it is a thermal sensor.(not trying to sound cheeky!) - i used a hot soldering iron at about 6-8 inches to see that the lights were turning on and off etc

jhb

TheHindmost

I was asking whether you were measuring the output of the sensors themselves or just using the LEDs to decide the sensor was active. Thanks!

Will

hiaber

Sorry about that Will!

techrtr

So, is your DF flying alright now? I've found that it's a really good idea to practice flying without TI as much as possible. When it's not working properly, like when it's cloudy or the ground is wet, it's nice to be able to still fly your copter with control. Plus, you never know when you'll take off, assuming that TI is on and working properly, and surprise surprise, it's either switched off on the transmitter, or it's not calibrating properly because of conditions.

hiaber

oh yeah, its working fine. had my first flight (though brief) with ti yesterday, but up until then i've been flying without.

--jhb

Fesfly

I have two DFs - both react differently when I try the hand test. I get different sensitivity levels from each sensor when I put my hand in front of them. Some I can be a foot in front, while others inches. I haven't flown with Ti in sometime to test the difference but I don't think it is good.

TheHindmost

I don't think I'd place much stock in a sensor "hand test" that's done just using the green LEDs as reference. I think you need to measure the sensor output directly. The reason is that the firmware running those LEDs is not designed for the "hand test." It's designed to determine whether there's a sufficient difference in the thermal signature of the ground (which it assumes the rear sensors are pointing toward) and the sky (which it assumes the front sensors are pointed toward) for TI-enabled leveling to work properly.

Adam, is there an undocumented test mode we can place the DF in to do a good, well-defined individual sensor check? Or maybe Jeremy can check in here?

Now, if you have two DFs and you take them to exact same place and hold them the exact same way and try to calibrate them and they react differently, there's probably an issue. That test is valid because it uses the firmware as intended. But the "hand test" as described here doesn't...

Will

Fesfly

Sorry I wasn't clear, while not a scientific test I would expect both dfs to act the same, they don't. If I place my hand 1 foot in front of right front sensor it lights on df(1) - need to almost touch on DF(2).

TheHindmost

Maybe I wasn't being very clear (it wouldn't be the first time )...I'm saying the problem is that you've got the firmware outside of its normal operating envelope, so expecting the DFs to react identically isn't necessarily reasonable. A systems engineer (yes, I have been one, but not on RC devices) would say we're in the area of "undefined behavior." We also don't know what the sensor tolerances actually are. The heat of a hand at a foot or an inch may be immaterial when it's trying to see the horizon. So we don't know the algorithm which is driving those LEDs, and we don't know what the actual requirements on the sensors are, but we do know we're not using the system as intended. So the results of such a test are probably not very reliable.

We need more info from Adam and/or Jeremy to come up with a good "bench test" for the TI sensors.

Will

Sky High

You guys can call FMA Direct and speak to one of their engineers. They are the ones who make these sensor arrays. It is essentially the FMA Co-Pilot product that has been modified and licensed for the DF series. I think a few of us, including myself, have expected the Ti feature to deliver more than it's designed to do for the price. We all need to be a little more realistic. If you want something that will perform like a commercial or military product, it is available and will cost more.

www.fmadirect.com

flyingdutchie

Now thats interesting.I recently stumbled upon that product,never to realize they developed the Ti technology for the DF.
I have been reading a lot of reviews on the co-pilot and it seems to work better than our "Ti",as it seems to work fine on cloudy days too.
Now I havent had a good Ti experience unless the sky was almost clear blue [&:] .On overcast days only one led lights up during calibration
which now due to some bad experiences makes me decide to NOT fly with TI.

TheHindmost

Thanks, Sky!! I did not know that, great info.

Flyingdutchie, I'm usually able to get two LEDs even on an overcast day. Are you making sure to hold the DF away from you when you do the arming dance? (Well, dance is the wrong word for it...I'm sure not graceful when I try to reach around and hit that button!) I usually calibrate over cement (not asphalt, though).

Will

flyingdutchie

@TheHindmost:
Yes I do hold the DF in the proper way,but I usually calibrate on grass/sand or other soils and try to stay away from cement or other hard surfaces for the time being.[sm=cry_smile.gif]
Maybe it's just the time of year so hopefully spring and summer will bring some better temp differences.

draganfly.com

My Feedback: (40)

I can't really add anything useful to this discussion. I'm not aware of any secret or decisive tests that can be done on the Ti system.

There have been a bunch of posts in response to each other, and I'm not clear what the original idea is. Are we trying to figure out a good way to diagnose if Ti is working at its best?

-Adam

TheHindmost

Basically, yes...Summarizing, some folks here are using their hands as a heat source and noting the response of the green LEDs to determine whether the sensors are working. Festus has two DFs and has noticed that they respond differently to the hand test. My point was that that wasn't necessarily a valid test, since that type of test is not what the system was designed for.

So we're trying to come up with a good "bench test" to determine whether all the sensors are working correctly...Maybe the hand test IS valid...My point was that we need more information to figure that out.

Will

TheHindmost

Interestingly, [link=http://www.fmadirect.com/Detail.htm?item=1769&section=29]this page[/link] from the FMA site which talks about their FS8 Co Pilot product mentions using the hands as a heat source when teaching the system different radio setups.

Also, there's a [link=http://www.fmadirect.com/other_technical.htm]technical section[/link] on the FMA web site which appears to have a bunch of useful white papers.

Thanks again for the FMA pointer, Sky!

Will

techrtr

I can tell as soon as I lift off if TI is working properly. If it isn't, I land, re-calibrate and try again. If I still can't get it working properly I turn it off and fly without.

draganfly.com

My Feedback: (40)

I spoke with Jeremy, and our manufacturing guys test the Ti on every board with this procedure:

Power on board
Hold two fingers in front of two front IR sensors, then press arm button
Hold Draganflyer by base plate from below, then throttle up to around 2/3 throttle (around hover)
Hold your hand near the IR board. Whereever you are holding it, the helicopter should rotate away from (fly away from).

Hopefully I heard him right.

-Adam

TheHindmost

Thanks, Adam, I'll try that!

Will