Please select Into the mobile phone version | Continue to access the computer ver.
DJI S900 build " how to" for intensive aerial work
10483 26 2014-10-3
Uploading and Loding Picture ...(0/1)
o(^-^)o
fabien
lvl.2

France
Offline

Hi,

this is a small build log with tips for S900 when dedicated to intensive use. I hope it can be useful to anyone.

The first step will be to protect the retract servos cables with black nylon braid. Reason is, the multirotors used for intensive work are often left directly in the sunlight and UV's will, with time, damage the housing of the wires. It will also ensure a small protection against vibrations and eventual rubbing against mechanical components. For all servo wires, 6mm braid will do the trick. You will need to fit some heatschrink on both ends of the nylon braid, and secure it with a drop of epoxy ( or CA eventualy) so the heatschrink does not slip away from the nylon braid.

Heat up the heatschrink on the servos outputs once the cables are connected, so the heat will also bend the heatschrink so it can follow the curve / bending in a decent way.

P1000026_resultat.JPG    P1000028_resultat.JPG    P1000029_resultat.JPG

Once done, it's time to move to other connectors like the ESC connectors which run from the MCU to the Frames. Use 9mm braid on this one and make sure to keep the braid a bit short so cable will not be too rigid after for the final connexion. Here, i used a to long braid, i changed it to shorter so the cable does not create too much rigidity. You cna see in later pictures how it looks like with the correct lenght of braid applied. I sued the S1000 nice heatschrink that is provided for the coaxial power connectors.

Important thing is, the A2 MCU has small edges to allow right side insertion of the connectors for Futaba connectors / standard ESc connectors. These edges are also present deeper in the A2, and it is not rare that some people do not press further enough the connectors. Make sure they are totally and firmly pressed ! Once done, secure the whole thing with " Plastidip" or rubber compound : it will be easier to remove it in case of need, but it will offer a great protection against vibrations and accidental unplugging during flight.....

P1000031_resultat.JPG P1000032_resultat.JPG

Add a bit of 3mm braid on the antennas if you are using the intergrated receiver. Here, it is important to leave 3 mm or so between the heatschrinks and the MCU base so there no tension creatd by the braid extension. This could result in early breaking of the antenna wires ( baaad... ).

P1000033_resultat.JPG

Let's move to the power connectors of ESC's. The cables are just crimped in the gold plated connectors. For intensive use and traveling, this wil result in often "pulling" on the cables when unfolding arms. As the connectors are not visible when the plastic cover is installed, it will nto allow to see if a wire is slipping out of the connector. I decided to secure the crimping with soldering (removing the heatschrink around the crimped connector and soldering). As i had aready installed the arms ( no picture needed i guess..) i made it on the fly. If you do so, make sure to protect the frames with some tissues or carton or anything, and then cleanup the solderings with Flux cleaner.

P1000036_resultat.JPG

As this machine is built to perform aerial view in wet environment, i also decided, but it's optional, to apply soldering once the connetors are installed and tightened. Pro is that there will not be any bad contact risk, cons is that for maintenance, you will need an iron solder
After that, Plastidip (the black complound you ca see)  is applied to protect the connections against oxyation and humidity.

P1000042_resultat.JPG

Time now for installing the cover and process electronics installation.

P1000043_resultat.JPG

There are many ways to install the electronics on the S900, here is mine, like tastes and colours, everybody has his favourite so let's say it suits me as it is. IOSD Mark II will be installed and will need to be connected also to the Zenmuse Z15 GH4. There will not be any datalink so only 2 canbus ports are needed on the IOSD Mark II on this build. A " blank" mount testing is always a good thing as sometimes little suprises can occure when you make your final connections. For example i had to relocate slightly the IOSD Mark II to allow the video input connector to run without binding on the XT60 plugs..

I choosed to route the IMU cable with small adhesive tabs in a round pattern so it does not "fly" anywhere in the build.

When you perform your installation, make sure that you do not over twist or pull power cable of PMU or X1 cable, same for the IMU Extra CAN connector. They are fragile connections inside the casings and if you give one turn too much, you just wrapp of the thin wires inside or break the PMU power pads.. I will not make a drawing of what can happen in that case...  Worse, if you damage the PMU Canbus cable it will make the LED canbus connector worthless and you will encounter severe troubles when plugging the USD cable or using the bluetooth with abnormal behaviour in the software ( for example crazy numbers and so on). All these devices are delicat and wires must be routed with clean installation and no over constraining... Twisting hard these CAN bus or PMU power or X1 cable will lead in later crash for sure... This is also valid for GPS / compass and other connectors.

P1000045_resultat.JPG     P1000046_resultat.JPG     P1000049_resultat.JPG

Now that all wiring seems to have decent locations, it's possible to move to the next step... Flipping the machine upside down will allow to install the landing gears. Make sure to use thread lock on all screws, and check for threadlock on servo aluminum horn system also. Distance between the rubbers of the legs and the central alu T mount is approx 18,5 cm or so to get it centered from memory. Once all is secured, you can add a small drop of CA on the aluminum tube mounts with a sharp knife edge so it will run by capilarity between the aluminum support and the boom and will bring a small extra safety just in case.. Make sure to degrease the aluminum parts and the carbon tubes  before proceding, idealy just give a very light sanding with 240 grade sandpaper ( gluing will be much better) in both alu parts and carbon booms where they match together...

Time comes for the Zenmuse to be installed. I use 9mm nylon braid and also 6mm. If you sue some, make SURE that you leave some uncovered wiring especially for the connectors going on the GCU of the gimbal, so they can be twisted and bent for their insallation without pulling on the connectors hardly. I also remove 3 screws from the GCU to install it on thee support ,as there are 3 holes that match the screws holes. I then apply thread lock and fit the GCU in place by using the screws trhough the alu support.

P1000051_resultat.JPG P1000052_resultat.JPG P1000053_resultat.JPG

Then, install the gimbal, plug the wires ( you can protect some canbus wires with nylon bread, optional...) , plug the X1 connector from the PMU and check all connections + correct sequence between CAN 1 and CAN 2 ( or the IOSD or the Zenmuse will not work correctly..).

P1000061_resultat.JPG P1000062_resultat.JPG P1000063_resultat.JPG

P1000064_resultat.JPG

Next is the video transmitter AVL58 to be wired. Being a bit maniac i wanted a nice routing. Easy to achieve with a bit of heatschrink and patience. Heatschrink is anyway recommended if you run the flat wire from IOD to video TX through the frame holes so it does not get damaged by fiberglass edges.

For the compass, the mast and adapter shall be installed using slow cure epoxy, not CA ( Ca will not resist and will elad to GPS / compass unespected rotation in the best case, falling in the worst one..
Also, slow cure epoxy will allow you to place the mast and the GPS top support perfectly aligned by using simply adhesive tape exactly like if you were adjusting a boat mast by applying tension with tape to the frames on 3 or 4 spots.

P1000066_resultat.JPG P1000067_resultat.JPG

A bit of finishing for the other cabls ( video and accessories and you are all done ).

Make sure to use thread lock on the top carbon plate ( the one with the GPS / Compass). Also, it might be better to flip the GPS foldable support 180° so that when you fold the GPS shaft, it will fold forward and will avoid the cable output to face up ( can be damaged by pressure in the transporting case).

Hope this little build log helps ..

P1000068_resultat.JPG P1000069_resultat.JPG P1000070_resultat.JPG

P1000071_resultat.JPG P1000072_resultat.JPG P1000076_resultat.JPG

P1000079_resultat.JPG P1000080_resultat.JPG P1000081_resultat.JPG

P1000077_resultat.JPG

P1000078_resultat.JPG






P1000024_resultat.JPG
P1000050_resultat.JPG
2014-10-3
Use props
torsir
lvl.4
Flight distance : 438816 ft
  • >>>
Norway
Offline

Nice work
2014-10-5
Use props
SFOS900
lvl.1

United States
Offline

OMG,

you are my new HERO..... !

Nice work I do all that stuff to my Flame Wheel 550 about three years ago.

And yes I have a S900 under my desk, I have too much to do right now but I was planning to do the same to my airframe.

Where do you fly ?

2014-10-5
Use props
fabien
lvl.2

France
Offline

Hi,
thanks for the kind words, i fly in France at the CEEMA, it is in south of France between Aix en Provence and Saint Maximin La Sainte Baume.
Best regards,
Fabien
2014-10-5
Use props
fabien
lvl.2

France
Offline

Thanks
2014-10-7
Use props
Tahoe_Ed
Captain
Flight distance : 2605 ft
  • >>>
United States
Offline

fabien Posted at 2014-10-6 15:21
Hi,
thanks for the kind words, i fly in France at the CEEMA, it is in south of France between Aix en ...

Fabien.  Very nice build log.  Nice to see you here!
2014-10-11
Use props
fabien
lvl.2

France
Offline

Tahoe_Ed Posted at 2014-10-12 01:47
Fabien.  Very nice build log.  Nice to see you here!

Thank you
I hope to share some wiring and settings tips as often as possible on the other DJI Platforms
2014-10-12
Use props
uhayat
lvl.3

Pakistan
Offline

fabien Posted at 2014-10-13 07:40
Thank you  
I hope to share some wiring and settings tips as often as possible on the other DJI  ...

Whoa!!! I'm speechless!
Just when I was about to lose hope of finding an easy to follow S900 build log, came across yours....
Will be starting hopefully next week, will follow your exact leads.
Thanks and happy flying!
2014-11-15
Use props
mostey
lvl.2
  • >>>
United States
Offline

I like all the heat shrink you did but seems to me you forgot one of the most important things to do IMO..
That is to unscrew all motor mount plates with a T9, check and locktite the 7 motor mount screws and single grub screw which holds main shaft of motor. Along with this, check every solder point for chrome. Then mark the replaced 8 screws with a dab of whiteout so you can check between carbon motor plate without unscrewing. Only grub screw will not be easily visible. For the record, every screw except for 1 grub  was tight with locktite from DJI and every solder joint was flawless. Coming from the days of single rotor it's hard to trust a manufacturer will do this for you so it's a good idea to check, especially if you're flying a 17lb machine in a professional environment.
2014-11-23
Use props
Eirlink
Second Officer

Ireland
Offline

great build post. well done
2014-11-23
Use props
fabien
lvl.2

France
Offline

mostey Posted at 2014-11-24 02:15
I like all the heat shrink you did but seems to me you forgot one of the most important things to do ...

Hi,

all frames that come from DJI here are totally disassembled and re assembled with thread lock and reinforcement on the landing gears.
Checking for threadlock shall be done on any product that comes pre assembled, because even the blue compound that is on the DJI screws is not up to the task unfortunately when its present on the screws ...

I'm writing a complete PDF document and will finalise it soon, there is a temporary version on another thread ( i attached it here also), but needs more picture and explanations,i'll complete it when i have some time ,
Best regards,

Fabien
2015-1-8
Use props
fabien
lvl.2

France
Offline

Hi again,

here is the building tips temporary document, it will be completed whenever i have a bit of spare time

S900 Build Tips.pdf

618.51 KB, Down times: 130

2015-1-8
Use props
fabien
lvl.2

France
Offline

SFOS900 Posted at 2014-10-6 08:26
OMG,

you are my new HERO..... !

Hi,

i fly in South of France at the UAV Test center located near my company, but i will soon be flying half year i California, not too far away from San jose, as we work a lot with David ( my partner in USA since almost 10 years) and it will be easier for us to move faster by myself being on site a bit more often ))

Next time i come over in CA, if some people are interested, i might organise some evening training sessions for building and setting up DJI S900 / S1000 series multirotors at the hotel conference room.

These sessions will be totally free of charge, it's just a way for me to make the evenings busy .

I can also organise maybe something in Boston as i have good relationships with a local retailer and i have to come around someday..
2015-1-8
Use props
project41
lvl.3

United Kingdom
Offline

Excellent article, thank you for the detailed instructions
2015-1-10
Use props
fabien
lvl.2

France
Offline

project41@me.co Posted at 2015-1-10 20:05
Excellent article, thank you for the detailed instructions

HI, you are welcome, i am completing step by step the instruction book

I'm also writing a complete article for setting up Futaba 14 SG on the A2 and how to work on with gimbals for single or dual operators + full settings on transmitters.
BEst regards,

Fabien
2015-1-11
Use props
project41
lvl.3

United Kingdom
Offline

I have had a look at your build document and have decided to stop my build and incorporate your changes into my build
Thank you for your efforts

Gary
2015-1-11
Use props
fabien
lvl.2

France
Offline

Hi Gary, thank you for your kind words.
I would say that the most important is to make sure to "reinforce" the connectors crimping ( the black and red power cables coming out of the booms) as they are just crimped and there is a bit of tension when arms are folded, which pulls hard on these crimped connectors.
Just make sure to put a bit of Heatscrhink on the round connector before applying soldering so that the soldering does  not spread onto the connectors contact areas ( will be harder to install them properly the in the small blocks with screws).
Feel free to ask if you have any questions,
BEst regards,
Fabien
2015-1-12
Use props
Akoni65.email
lvl.2
  • >>>
United States
Offline

fabien Posted at 2015-1-8 22:54
Hi,

all frames that come from DJI here are totally disassembled and re assembled with thread loc ...

Fabien,

Did you ever post the PDF build document anywhere? I'd love to have a look.

Tony
2015-1-28
Use props
claus.kjerkegaa
lvl.1

Denmark
Offline

Great post, thanks !
2015-1-30
Use props
fabien.email
lvl.2

France
Offline

Akoni65.email Posted at 2015-1-29 04:27
Fabien,

Did you ever post the PDF build document anywhere? I'd love to have a look.

Hi,

yes, it is on my website, but here is a direct link for downloading the document,

http://www.e-copter.com/portal/w ... S900-Build-Tips.pdf

BEst regards,

Fabien
2015-1-30
Use props
fabien.email
lvl.2

France
Offline


You are welcome

I plan to make a video during a complete build next month and will post it hen it's done.
Some tips are hard to explain with just pictures and text, video will " talk" much better especially when explaining the horizontal vibration problems
BEst regards,
Fabien
2015-1-30
Use props
Akoni65.email
lvl.2
  • >>>
United States
Offline

fabien.email Posted at 2015-1-31 07:16
Hi,

yes, it is on my website, but here is a direct link for downloading the document,

Great, thank you.
2015-1-30
Use props
momochi
lvl.3

United States
Offline

Fantastic work. I am so impressed and inspired. Thank you for taking the time to share your build up. I will follow your advise.
2015-1-31
Use props
fabien.email
lvl.2

France
Offline

Hi, you are welcome
DJi are very good products when you know how to deal with them, with technology and " RTF" things evolving, people sometimes forget the principles of all these equipment, which is a bit of RC Hobby skills and little time to spend.
But once you get your hands in your machine, take the time to check it, correct small things, you end up with a solid aerial platform.
So far, since i sell DJI RTF system that we build with care at the workshop, my customers never experienced a single failure in flight.
It costs us more time to build, but we have no after sale to provide except general maintenance, and upgrades
BEst regards,
Fabien
2015-2-6
Use props
fabien.email
lvl.2

France
Offline

Tahoe_Ed Posted at 2014-10-12 01:47
Fabien.  Very nice build log.  Nice to see you here!

Hi Tahoe-Ed,
is there a way to contact you via PM or Email for a small information request ?
Thanks a lot,
Fabien
2015-2-6
Use props
Tahoe_Ed
Captain
Flight distance : 2605 ft
  • >>>
United States
Offline

fabien.email Posted at 2015-2-7 02:26
Hi Tahoe-Ed,
is there a way to contact you via PM or Email for a small information request ?
Thank ...

Fabien, can you contact me on RCG and I can send you my email address.

Ed
2015-2-6
Use props
fabien.e-copter
lvl.2

France
Offline

Hi Ed, Thanks for your message, i send you a MP on RCG
2015-2-7
Use props
Advanced
You need to log in before you can reply Login | Register now

Credit Rules