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New props = uncontrollable ascent to max alt.!

umanbean

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My new props from Amazon (anbee 5-color) arrived here about an hour ago.

I was busy but took a break, anxious to try them for good fit. They fit just as tightly as OEM, minimum wind today, so I took it outside to the back deck for a test run.

I mostly hand launch, and as soon as I dropped my hand Tello took off straight up - fast.

Full throttle down brought it down about a meter, but it took off again - and no stopping it this time no matter what I did!

As it ascended full throttle straight up and the dot got smaller and smaller I wondered if it would stop... and at the same time was thankful that it was straight up and not off over the woods!

I heard it finally stop ascending, pulled throttle back and down it came - full throttle down and no stopping it no matter what I did. It slammed into the ground, but thankfully no damage.

Brought it inside and it did the same thing twice, slamming into the ceiling and falling.

It finally occurred to me to restart Tello and the app - everything back to normal... flies fine, reacts to all commands... weird, scary, thankful...
 

umanbean

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Have a video? Maybe the props are damage. had you a crash with Tello?
No video, new props - inspected as they were installed. And yes I've 'crashed' it many times, mostly inside bump-n-falls. This was not due to a crash.

After rebooting everything it flies fine. Did my first ever gravity calibration anyway.

I just wondered if anyone knew why it might have went nuts like that? Nothing changed except the props. I flew it several times this morning inside and outside before the prop change.
 

MrSpok

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The Tello could not fly stable if props are damaged.
Could be a bug in the Tello software or in your smartphone. Which app do you take to fly?

Inside your Tello and inside your phone is a little computer. Didn't you have it sometimes on your desk-PC that it simply hangs up himself and after a reboot everything works fine again?
With your Tello it is the same as well.
 

Santiago

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One of my Tellos did this. I had stock props, but i was using a wifi extender and bluetooth controller. I chalked it up to one of those, but I was not really satisfied. It was pulsing full throttle up, in long bursts, and mine did drift, about a 1/4 mile away. I quickly hit record to start video, as what was far less than a minute, played out in what truly felt like forever. (Crazy how that happens.) Water separated me from where it was heading, so i got to the edge of it and just held my [spare] phone up, and the wifi repeater, trying to keep the video link going so I could see where it landed. I managed to keep the link but it was still inconclusive. When I got around the water, and into the area, I pick up signal and used signal strength to zero in on it. That, in combination with the last frames of the live feed allowed me to find it right behind a plastic picket fence, sitting in landscape gravel i recognized from the feed. I could not reach it though. I started looking for a stick, anything to reach it, but there us literally never a single stick at this park, because they clean them up constantly. Then, as if it was planned, 5 feet away I found a 2.5' long metal rod, with 2 inch, 90 degreee bend on one end, like a hook lol! It was PRECISELY the length I needed. I reached it through a narrow gap in the fence, hooked an arm, and delivered it directly to my other hand. I didnt fly either Tello again for a couple weeks.

It's the one I received as a warranty replacement and there have been some strange things about it. There is a small hole in the bottom, that looks like a reset button hole, but is not. It flew eradically prior to this, and sadly since then. I finally decided maybe it was the motors. Maybe they were worn out, which would mean my warranty replacement was a bit of a rip off.. Anyway, I replaced all four motors with a set from Amazon that I got for $14. I created slack in the motor wires, as I did them one at a time, and spliced in the new motors with about 1cm length of the new motor's wire. (I cut off the old motors, right up against the motor, leaving full wire length.) It really seems to fly much better, as if I addressed the problem. The new motors sound great, but they dont have quite the punch out of stock motors, but a whole set costs as much as just 1 stock motor as well, sooooo..

Anyway, that is my story. I am glad you got yours back without a hunt. If you have more erratic behavior, and you have lots of hours on it, or it's a warranty replacement, consider new motors. You literally cannot tell Ive replaced mine by looking at it. Later today, Ill edit this reply with the fly off video, and a current photo of the Tello (and for grammar, etc.)

EDIT- Ive actually made a new reply below, with the video and photo.
 
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umanbean

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One of my Tellos did this
Thank you for your reply, at least I know I'm not the only one this has happened to.

Your incident was a lot more interesting than mine and with a lot more oh-sh*t moments! :) I'm glad you found it and was able to retrieve it!

On my phone right now, will reply more later when I get home, thanks again.
 
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umanbean

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I quickly hit record to start video, as what was far less than a minute, played out in what truly felt like forever. (Crazy how that happens.)
That's quick thinking right there, it never occurred to me to start video but should have!

And btw, your grammar is perfect, don't bother changing
 
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leandjb

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Here is my video. Happy to answer any questions:

And here is the little misbehaver, and a shot of the 'reset,' hole on the bottom:
The tiny hole no is normal in tello and in that zone is the "antenna test port". Check this:
3663
 

leandjb

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Here is my video. Happy to answer any questions:

And here is the little misbehaver, and a shot of the 'reset,' hole on the bottom:
And in the video, do you remember a battery percent? Always in critical level the aircraft do "autoland"
 

umanbean

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Anyway, I replaced all four motors with a set from Amazon that I got for $14.
I'm shopping Amazon right now for motors. The "Amazons Choice" is from RCGEEK, 4 motors for 13.98... that's the one to get?

I weighed the OEM props and several of the Anbee ones.

OEM
3 @ 0.55 grams
1 @ 0.54 g

Anbee
1 @ 0.40 g
2 @ 0.43 g
4 @ 0.45g
1 @ 0.47g

So the Anbee props are not only lighter, but weight varies at least 0.07g and they're more flexible.

I'm wondering if less weight + variance + less stiff could all combine to confuse the Flight Controller enough to cause an uncommanded full throttle ascent to max altitude?

The reason it did that is still a head-scratcher to me...
 

Santiago

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I'm shopping Amazon right now for motors. The "Amazons Choice" is from RCGEEK, 4 motors for 13.98... that's the one to get?

I weighed the OEM props and several of the Anbee ones.

OEM
3 @ 0.55 grams
1 @ 0.54 g

Anbee
1 @ 0.40 g
2 @ 0.43 g
4 @ 0.45g
1 @ 0.47g

So the Anbee props are not only lighter, but weight varies at least 0.07g and they're more flexible.

I'm wondering if less weight + variance + less stiff could all combine to confuse the Flight Controller enough to cause an uncommanded full throttle ascent to max altitude?

The reason it did that is still a head-scratcher to me...
Yep, those are those motors I got. I cannot speak for their longevity yet. As I mentioned, Ive not had any of the poor control that I had prior. Only accumulated flight time will tell though. Ill be ripping some packs this afternoon for sure.

I just weighed a handful of my makerfire 75mm and 76mm props. The 76mm are the same weight as oem, and while they varied between .54 and .57, it is mostly across different colors; for instance, of 5 different pink, 76mm, 4 were .55, and 1 was .56. The 75mm seem similar, but their average weight is around .88. I love both of these styles of props, and I fly them with mixed colors. I've never had an issue that I would relate to them. Ive consistently associated some of my control issues to extender, and bluetooth controller, but I also had the odd day that the combo flew flawlessly. Hands down, most consistent is OTG to my X-Lite, with or without the extender.

Let me add that I really screwed up, chasing a problem that was my fault for a couple weeks. I would really have to fight the major erratic behavior. My mistake came from the fact i sometimes used my actual phone S8+ to fly, but mostly I used a spare Note 8 without service to fly. I would connect to the extender with the Note, while in my pocket, the S8+ had wifi on, and was set to auto connect to the extender. Some days id have it off and flying would be great, though i had no idea why at the time. It finally occurred to me in the middle of a session. I pulled out my S8+, and sure enough it was connected. I turned wifi off, and bluetooth to be thorough, and immediately had great flights. Anyone using multiple devices to fly, and has problems with erratic flight, should consider this. When I had the flyoff, Im pretty certain i had already figured this out, but i honestly cant confirm that I remembered to disable wifi on my S8+ that day. That should be part of my story, but at the time it happened, i could only think "extender," so thats how i recalled it.

I can tell you for certain it had nothing to do with my battery level, and how one sees a complete loss of control, and Tello repeatedly punching out on its own until it appeared to exceed the firmware altitude limit, and relates it to and auto land sequence and a dead battery, I do not know. Perhaps im overlooking something there, so Im all ears if anyone wants to expand on that proposition.

Try those motors. If you got the dough, by all means get oem, but for the price, I am so far pleased with the RCGEEK, $14 set. Just let me know if you want details of my replacement process. Everyone else online seems to be adding hideous connectors, or working way too hard, soldering to the board. Ill be happy to write it up, with photos and insight, if requested. My FC, antenna wires, etc., are still pristine, the full runs of stock motor wire are maintained, and quite literally you cannot tell it's been repaired, unless you pulled a motor, where youd find one clean 5-6mm length of shrink boot on each wire, 1 cm from the motors. I do have a vision of hiding connectors in there, so that i could mod a new set of motors with the plug flush to the bottom of each one, and have them available for a quick swap the next time i needed to. If these motors go quick, I may try it.
 
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Santiago

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The tiny hole no is normal in tello
I agree completely; the tiny hole is not normal. Neither of my Tellos from the store have the hole. Only the warranty replacement does.

And Im sorry, I have no idea what you are showing me in the photo. Im clueless to an "antenna test port," and the photo does nothing to change that fact, neither does it demonstrate the hole in my example. If it was your intention to be informative, maybe you can help me out and add some more info. I love learning, and find it easy to admit when im wrong, or overlooked something. I also need plenty of details to link things together. Im simply am not bright enough to draw conclusions from meager amounts of data. I take a very long time to do much of what i manage to accomplish, so thank you in advance for understanding, and taking me by the hand. You put your reference to the test port in quotes, so perhaps you can begin by sharing a link to the documentation you are quoting. Thank you, my good person.
 

hologram

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One of my Tellos did this. I had stock props, but i was using a wifi extender and bluetooth controller. I chalked it up to one of those, but I was not really satisfied. It was pulsing full throttle up, in long bursts, and mine did drift, about a 1/4 mile away. I quickly hit record to start video, as what was far less than a minute, played out in what truly felt like forever. (Crazy how that happens.) Water separated me from where it was heading, so i got to the edge of it and just held my [spare] phone up, and the wifi repeater, trying to keep the video link going so I could see where it landed. I managed to keep the link but it was still inconclusive. When I got around the water, and into the area, I pick up signal and used signal strength to zero in on it. That, in combination with the last frames of the live feed allowed me to find it right behind a plastic picket fence, sitting in landscape gravel i recognized from the feed. I could not reach it though. I started looking for a stick, anything to reach it, but there us literally never a single stick at this park, because they clean them up constantly. Then, as if it was planned, 5 feet away I found a 2.5' long metal rod, with 2 inch, 90 degreee bend on one end, like a hook lol! It was PRECISELY the length I needed. I reached it through a narrow gap in the fence, hooked an arm, and delivered it directly to my other hand. I didnt fly either Tello again for a couple weeks.

It's the one I received as a warranty replacement and there have been some strange things about it. There is a small hole in the bottom, that looks like a reset button hole, but is not. It flew eradically prior to this, and sadly since then. I finally decided maybe it was the motors. Maybe they were worn out, which would mean my warranty replacement was a bit of a rip off.. Anyway, I replaced all four motors with a set from Amazon that I got for $14. I created slack in the motor wires, as I did them one at a time, and spliced in the new motors with about 1cm length of the new motor's wire. (I cut off the old motors, right up against the motor, leaving full wire length.) It really seems to fly much better, as if I addressed the problem. The new motors sound great, but they dont have quite the punch out of stock motors, but a whole set costs as much as just 1 stock motor as well, sooooo..

Anyway, that is my story. I am glad you got yours back without a hunt. If you have more erratic behavior, and you have lots of hours on it, or it's a warranty replacement, consider new motors. You literally cannot tell Ive replaced mine by looking at it. Later today, Ill edit this reply with the fly off video, and a current photo of the Tello (and for grammar, etc.)

EDIT- Ive actually made a new reply below, with the video and photo.
The little tiny hole on the bottom of the Tello (between the visual positioning sensors) is for the barometric pressure sensor to operate properly. This sensor is used to tell the Tello how high in the air it is relative to its launch point.

The hole you posted in your photo looks like there was either a bubble in the mold when the part was produced, or melted somehow.
 

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The little tiny hole on the bottom of the Tello (between the visual positioning sensors) is for the barometric pressure sensor to operate properly. This sensor is used to tell the Tello how high in the air it is relative to its launch point.

The hole you posted in your photo looks like there was either a bubble in the mold when the part was produced, or melted somehow.
The sensor in the middle of vps is a vga camera for horizontal position lock. That tiny hole on the black heat radiator is just a hole where a rod from the main circuit board partially pokes into. It could be used to align the mounting the heatsink, it certainly is no reset button as i see no button mechanism under the rod.
 
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hologram

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The sensor in the middle of vps is a vga camera for horizontal position lock. That tiny hole on the black heat radiator is just a hole where a rod from the main circuit board partially pokes into. It could be used to align the mounting the heatsink, it certainly is no reset button as i see no button mechanism under the rod.
The only sensors for VPS are the two large black spheroid lenses... the small pinhole is for the barometer. The pinhole that's in the photo up there is some sort of defect.
 

Guorium

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The only sensors for VPS are the two large black spheroid lenses... the small pinhole is for the barometer. The pinhole that's in the photo up there is some sort of defect.
Absolutely not true. It is common knowledge that tello has two cameras. You go ask Ryze support and they would tell you that too. The forward one and the downward one which is in between the ir transmitter and receiver (two black spheres as you described).

Have you not been reading? I opened my tello and I saw a rod going up to that hole in the sink radiator. It is there for a purpose. At the end of the day you can burry your head in the sand but don’t expect people to buy your misinformation.
 
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Santiago

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Haha this is great. I guess we're about to see Cunningham's law swing into full effect, and I'll do my best to start it by attempting to address VPS. You can find anything I quote in the Tello User Manual, found here. My paraphrasing is due to the fact Ryze/DJI have set features on the document that prevent me from copying text directly, or even opening it in an editor like Word.

VPS - Vision Positioning System: "helps the aircraft maintain its current position; hover in place more precisely. The main components of the VPS are a camera, and a 3D infrared module located on the underside of the aircraft."

So, the complete sensor array, the three circular components contained in an oval on the bottom, together make up the VPS. One of the IR domes is an IR LED, easily identified in low light by the faint red light it emits. Its counterpart is an IR receiver, and noticebly does not illuminate like the LED. And, obvious to most, the center component of the VPS, between the IR emitter/receiver combo, is a camera. See the photo I've attached to see how the complete array is what is referred to when we say VPS. If you want to be more specific, you can talk about the camera, or you can refer to the IR combo. Parameters within which the VPS is functional, or optimal, or any of its behavior, or effectiveness, in different conditions is beyond the scope of this exercise in definitions, and can be found in the manual linked above.

To be clear, I personally had zero misconceptions about VPS, but I can't stand to see a thread deteriorate into a flood of hastily posted misinformation. I make this post in the spirit of maintaining the value of this forum for current and future members, and lurkers alike. My success in most(?) of my personal, and professional endeavors, can in part be attributed to the generous, active users and authors of countless threads, across countless forums, covering equally as many different topics (massively broad are my interests.)

Regarding the altimeter discussion, I aim to come back and offer definition for that sensor as well. For now I'm out of time. I certainly don't discourage anyone that may want to step up and provide accurate information on Tello's altitude sensor, complete with citations/references/link/etc., before I can.

As well, it is clear I need to clarify which hole (with a big red arrow pointing at it,) I am referring to, and my position, and observations on it when I return.

Cheers-
 

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hologram

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Absolutely not true. It is common knowledge that tello has two cameras. You go ask Ryze support and they would tell you that too. The forward one and the downward one which is in between the ir transmitter and receiver (two black spheres as you described).

Have you not been reading? I opened my tello and I saw a rod going up to that hole in the sink radiator. It is there for a purpose. At the end of the day you can burry your head in the sand but don’t expect people to buy your misinformation.
Absolutely not true. It is common knowledge that tello has two cameras. You go ask Ryze support and they would tell you that too. The forward one and the downward one which is in between the ir transmitter and receiver (two black spheres as you described).

Have you not been reading? I opened my tello and I saw a rod going up to that hole in the sink radiator. It is there for a purpose. At the end of the day you can burry your head in the sand but don’t expect people to buy your misinformation.
I said the only two sensors used *for VPS*. Maybe before accusing me of not knowing how to read, you should read my own comment first. I am well aware of how the sensor system works. I know how the gyroscope works, the barometer, two cameras (I never said there were other than two cameras), etc... I have a degree in telerobotics from a well known institution and I am continuing classes. There’s no need to be so rude and condescending... I’m not “peddling misinformation,” I think you’re paranoid or something. When I said my original statement, I was trying to tell people (who were focused on a “pinhole”-shaped opening under the drone) that it wasn’t a part of the VPS. Don’t be such a butt and don’t accuse me of giving out misinformation!
 
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umanbean

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I have a degree in telerobotics from a well known institution
Don’t be such a butt and don’t accuse me of giving out misinformation!
I respect your credentials and I'm not trying to be a butt...

But in your first two posts, you said:

The little tiny hole on the bottom of the Tello (between the visual positioning sensors) is for the barometric pressure sensor to operate properly.
Not true

The only sensors for VPS are the two large black spheroid lenses... the small pinhole is for the barometer.
Also not true.

The pinhole between the IR emitter and sensor is a camera - the barometer doesn't need a hole.
 

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