Tear Down Photos (Voiding my Warranty so You Don't Have to)
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Duane Degn
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Flight distance : 622234 ft
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I know I'm not alone in feeling a need to take things apart. Sometimes I find I can restrain my urge to take things apart if someone else does it and shares photos. Here are some photos of the inside of the turret base. Maybe I can help someone else not void their warranty by sharing these photos.

The PCB receives the CAN Bus single and passes the CAN Bus signal on to three other PCBs.
One of the sets of four wires (marked with blue) is routed up the left side of the turret. The other wires are routed up the right side of the turret.

Here's the other side of the base PCB.

I was not able to read the markings on the chip seen above. My guess is it's the board's microcontroller. Based on the wide traces coming from the he chip on the other side of the PCB, I think the chip seen in the top photo is an electronic speed control chip for the brushless motor. After removing the conformal coating, I was able to better read the markings.

The top line appears to read "MPS1839." The second line appears to be "MP6536." I wasn't able to figure out which chip this is.
I have additional photos at my Hackday IO page project page. (I don't always have success with links so I'm adding the URL text below.)
https://hackaday.io/project/167276-dji-robomaster-s1-hacks/log/168460-turret-teardown-pan-base
Assuming these sorts of posts are okay with DJI, I'll update this thread when I have additional photos to share.

2019-9-11
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DJI Tony
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Hi, thanks for sharing these photos to our valued DJI Forum members who might curious about this. Indeed, this process is not in accordance to our after-sales service and we always recommend our customers abiding by our after-sales service to enjoy the warranty of the product. Thank you for your support.  
2019-9-11
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MarkusXL
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This is really cool though, thanks for sharing and bravely sacrificing your warranty, to further our knowledge of this fascinating product!  How can one even resist to take it apart?  

A lot of us are engineers and totally geek out on this stuff

Technical sticking point with me - I challenge the use of the nomenclature "conformal coating".  I have inspected thousands of PCBs over the decades, and this appears to me to be "ROSH compliant no-clean flux residue".  Yeah it says "no-clean" and that's why nobody cleans it off but every time I solder something I clean it off well that's just me

I have seen actual conformal coatings, and the samples I saw were a heavy, tough, expoxy-like coating that totally seals the circuitry and thus prevents any access or rework to the components so encased.  The military uses this commonly.


The no-clean flux residue is easily cleaned off with isopropyl alcohol (use 90% or better), while as a conformal coating is often permanent and generally not removable without damaging the circuitry.

2019-9-11
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Duane Degn
Second Officer
Flight distance : 622234 ft
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"I challenge the use of the nomenclature conformal coating."

I assure it is NOT flux.
While conformal coating can be heavy, it can also be relatively thin. The last conformal coating I purchased was some of this stuff.

I purchased it from Amazon. The product name is "MG Chemicals 422B Silicone Modified Conformal Coating, 55 ml Bottle"
On multiple circuit boards, it's very clear the material is purposefully placed. Here's one photo showing how the coating has been added while avoiding the QR code and connectors.

Here's another view of the PCB show at the top of my original post.

Here again it's clear the material is purposefully placed so as to avoid the QR code and connectors.
A thin layer of conformal coating is often used on hobby grade products such as quadcopters and other RC vehicles to prevent moisture damage when used in the rain or on wet grass. I believe this is the purpose of the coating on the Robomaster S1's PCBs. Rather than sloppy workmanship, it's showing DJI is making an effort to add a layer of moisture protection.
This coating does not come off nearly as easily as flux.
2019-9-11
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Duane Degn
Second Officer
Flight distance : 622234 ft
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I've added some additional photos to my Hackaday IO project page. https://hackaday.io/project/1672 ... t-teardown-pan-base
I've documented portions of the turret's tilt mechanism. I shared one of the photos above to show the way the conformal coating is used. Here are a few more.



I'm not sure, but I think the above metal piece is made from sintered powdered metal.
The tilt mechanism's microcontroller is an Atmel ATSAME70N19.
If I understand the purpose of the goop, I think it's to keep the IMU at a constant temperature to reduce gyro drift.
There are a few more photos at my project page.
I plan to share some photos of the inside of the camera, speaker and gel blaster soon.
BTW, there are several tamper detection systems on most of these items. It will be very easy for DJI to see if these parts have been opened.
2019-9-11
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Duane Degn
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Flight distance : 622234 ft
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I added a log about the Robomaster S1's speaker.
https://hackaday.io/project/1672 ... 72-speaker-teardown
Before opening the speaker, I decided to shine a violet laser at a small blob of glue inside one of the fastener's heads. The glue brightly fluoresced. I think this is one of several way DJI can determine if the enclosure has been opened. The glue must be destructively removed in order to remove the fastener.

There's a 4 Ohm speaker inside the enclosure.

There's also a weight.

I'm not sure the purpose of the weight. It could be used to balance the gimbal or it could also effect the sound quality by changing the way the enclosure resonates with the sound from the speaker.
2019-9-12
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MarkusXL
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Duane Degn Posted at 9-11 22:07
"I challenge the use of the nomenclature conformal coating."

I assure it is NOT flux.

Ok good - there is some new goop I have to be aware of now.  Ah yes I see in that picture, the color and the placement.  Thanks for this info!
2019-9-12
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MarkusXL
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Duane Degn Posted at 9-12 00:47
I added a log about the Robomaster S1's speaker.
https://hackaday.io/project/167276-dji-robomaster-s1-hacks/log/168672-speaker-teardown
Before opening the speaker, I decided to shine a violet laser at a small blob of glue inside one of the fastener's heads. The glue brightly fluoresced. I think this is one of several way DJI can determine if the enclosure has been opened. The glue must be destructively removed in order to remove the fastener.

I suspect it's a gimbal balance.  It is pretty well balanced.

I am eager to be able to program more stuff through the Speaker.
2019-9-12
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DanMan32
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Flight distance : 2489501 ft
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As a kid, when I'd get something mechanical or electronic, first words out of my parents' mouth was "Now down't take it apart!"  That would last a month or two.
The interesting thing is, I inherited that curiosity from my mother, who was not technically inclined rather than my dad who understood mechanics and some electronics, but didn't feel the need to take things apart unless it was to fix it.
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