On this tutorial, I’ll information you thru establishing the DJI O4 Lite Air Unit in any FPV drone. This contains wiring it to the flight controller, configuring Betaflight OSD, and sharing helpful ideas together with the greatest transmission and digital camera settings to realize optimum efficiency in your particular wants.
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The place to Purchase?
You should buy the DJI O4 Lite Air Unit from the next retailers:
Presently, elements will not be offered individually, which means when you break the digital camera or transmission module, you’d have to switch the complete air unit. Hopefully, spare elements will turn out to be out there sooner or later to make repairs extra reasonably priced. Nevertheless, the antenna is well detachable and replaceable.
Mounting
The O4 Lite Air Unit is designed for micro-sized FPV drones, equivalent to tinywhoop and ultralight quads. Since these small drones usually use a flight controller with a 25.5×25.5mm mounting sample, it’s attainable to mount the O4 AU instantly on high as a part of a single stack.
Many trendy frames have devoted areas within the rear for mounting the VTX, however this will likely not at all times work for the O4 Lite because of its brief digital camera cable (solely 5cm lengthy).
Picture Credit score: Calpulz
The actual problem is mounting the digital camera because of its unconventional mounting system. When you’ve got entry to a 3D printer, you would design a customized mount in your present body. In any other case, you would possibly must buy a brand new body designed particularly for the DJI O4 Lite. Simply to call a few these new frames:
Moreover, be certain the antenna is securely strapped to one thing like the cover. The antenna is just friction-fitted, which means the U.FL connector may pop off in a crash.
Disconnecting Digital camera and Antenna
It’s attainable to disconnect the digital camera from the transmission module, however the coaxial cable/connectors are glued in place. Except you’ll be able to reapply the glue after reconnection, I don’t advocate disconnecting them. Eradicating or changing the antenna is easy although.
Powering the O4 Lite
The O4 Air Unit (Lite) may be powered instantly from a 1S, 2S, or 3S LiPo battery (3.7–13.2V). Nevertheless, the Air Unit could turn out to be unreliable and even shut down when the voltage drops beneath 3.7V. Subsequently, it’s not beneficial to energy the O4 Air Unit instantly from a 1S LiPo. As a substitute, energy it from a steady 5V or 9V BEC on the flight controller, which additionally supplies further safety towards voltage spikes.
Energy necessities:
- Max energy consumption: ~6W
- Present draw at 700mW: 5V 1.2A or 9V 0.67A
- Beneficial BEC: Minimal 5V 2A BEC or 9V 1A BEC (When you’ve got different power-hungry units, think about using a higher-rated BEC)
Flight Controller Connection
The DJI O4 Lite Air Unit makes use of the similar 6-pin connector and pinout because the O3 and O4 Professional, making it plug-and-play with any flight controller designed for present DJI Air Items. Nevertheless, it’s best to at all times double-check the wiring upon connection to keep away from any surprises.
Pinout of the 6-pin connector:
- VCC: Energy provide
- GND: Floor
- RX/TX: Required for OSD and telemetry (e.g., displaying battery voltage and arming detection)
- GND and SBUS: For DJI Distant Controller (non-compulsory)
Not like the O4 Professional, the O4 Lite doesn’t have solder pads. If you wish to solder it on to the flight controller, you will have to minimize off the connector from the cable and strip the wires.
If you’re not utilizing a DJI Distant to manage the drone, and are as a substitute utilizing your personal radio receiver, it’s beneficial to take away the SBUS wire (DJI HDL) from the connector. This may forestall potential conflicts. Use a pointy software, equivalent to a pin or needle, to barely elevate the tab within the connector and pull the wire out. On this case you might also take away the extra floor wire (brown).
Activation
As soon as the O4 Lite is related to the flight controller (FC), it’s time to activate it. If the Air Unit was beforehand activated, this step just isn’t required.
Professional Tip: that the O4 Air Unit should be powered by a battery or a accurately rated energy provide throughout activation. Not like the O3, it can’t be activated utilizing simply the USB-C cable. Though the USB-C cable just isn’t included, any USB-C information cable will work.
Obtain DJI Assistant 2 (Shopper Drone Sequence): https://www.dji.com/nl/downloads/softwares/dji-assistant-2-consumer-drones-series.
When you’ve got put in it, it’s nonetheless a good suggestion to obtain and re-install the newest model.
Professional Tip: activation CANNOT be finished within the DJI Fly App.
Firmware Replace
Whereas related to DJI Assistant 2, test if new firmware is on the market in your O4.
Professional Tip: For firmware updates, you’ll be able to safely unplug the battery throughout the course of to keep away from heating.
Pairing DJI Goggles 3 with O4 Lite
Earlier than pairing, guarantee your Goggles 3 firmware is up to date to the newest model. With out this replace, you received’t get the O4 Professional and O4 choices within the menu. Observe these steps:
Replace Firmware
- Activate the Goggles 3 and join them to your pc utilizing a USB-C information cable.
- Replace the firmware by way of DJI Assistant 2.
Professional Tip: If the Goggles 3 doesn’t seem in DJI Assistant 2, navigate to the goggles menu:
Settings → About → OTG Wired Connection and allow it.
Choose O4 Air Unit Professional within the Goggles Menu
- Go to the goggles menu, navigate to Standing → Change, and choose “DJI O4 Air Unit.”
Enter Bind Mode
- Press and maintain the ability button on the goggles till they begin beeping, indicating they’re in bind mode.
Energy on the O4 Air Unit
- Look ahead to the LED on the Air Unit to show crimson.
- Press the bind button on the Air Unit. The crimson LED will start flashing slowly, indicating it’s in bind mode.
Full Binding
- Binding is profitable when the LED on the Air Unit turns stable inexperienced, and the goggles show the digital camera feed.
Pairing Goggles 2/Integra with O4 Lite
To make use of the O4 Air Unit with Goggles 2 (or Integra), you’ll must replace the firmware on each units. And don’t fear, you’ll nonetheless get compatibility with the O3 Air Unit, in addition to older DJI FPV Air Items and the Vista system.
Professional Tip: When you’re utilizing a Mac and encounter connection points (e.g., Goggles 2 not showing in DJI Assistant 2), it is a recognized downside. Sadly, there isn’t a dependable repair. A workaround is to replace utilizing the DJI Fly App in your smartphone or change to a Home windows PC for the firmware replace.
After the replace, go to the goggles menu and choose both O4 Air Unit or O3 Air Unit below the settings.
Press the hyperlink button between the lenses on the Goggles 2 to enter bind mode.
Energy on the O4 Air Unit and await the LED to turn out to be crimson. Press the bind button on the Air Unit. The crimson LED will flash, indicating bind mode. Binding is profitable when the LED turns stable inexperienced, and the digital camera feed seems in your goggles.
Switching Between Professional and Lite
When you use each the O4 Professional and O4 Lite, bear in mind to change between them within the goggles menu earlier than flying. Every time you fly with a distinct unit, you’ll must manually choose the corresponding Air Unit within the goggles settings.
Unlock FCC Mode
In case your Goggles 3 are shipped with CE mode (to adjust to European rules), they are going to be restricted by way of output energy (solely 25mW) and channels. There shall be only one out there channel within the 40MHz mode and three out there channels within the 20MHz mode.
In FCC mode, it’s best to have the utmost 1200mW output energy possibility, and there must be 7 out there channels within the 20MHz mode, and three out there channels within the 40MHz and 60MHz mode.
For goggles in CE mode, it’s attainable to carry out the “FCC hack” to unlock larger output energy (extra vary and sign penetration) and extra channels (permits extra pilots within the air on the similar time), however solely do that if it’s authorized the place you fly.
To change to FCC mode, merely get the file “ham_cfg_support”, unzip it to the basis listing of the SD card and put it within the goggles, energy on goggles, that’s it.
Obtain file right here: https://drive.google.com/file/d/1ug2U_i5kdrKQQ2I17NLJBXm2tKQeNj5Q/view?usp=share_link
To test in case you are in FCC mode, go to Settings => Transmission => Channel Mode, change to Handbook, below 40MHz or 60MHz bandwidth, it’s best to see 3 channels out there in FCC mode. If it would solely present 1 channel there, you’re in CE mode.
As soon as FCC mode is unlocked, you received’t must do it once more. You may return to CE mode by manufacturing facility reset the goggles (within the menu Settings => About).
Setup OSD in Betaflight
The DJI O4 Air Unit totally helps the Betaflight OSD, together with the Betaflight OSD menu and all out there OSD parts.
Go to the Presets tab, and seek for “dji”, the “FPV.WTF MSP-OSD” preset ought to pop up. In choices, choose the UART you might have related to the O4 Lite Air Unit.
To allow HD OSD, go to the settings menu within the goggles, Settings > Show > Canvas Mode, and choose HD OSD.
This lets you show the OSD with smaller fonts and drag OSD parts all the best way to the sides of the display. If you choose Regular Mode, the font will seem a lot bigger.
Lastly, go to the OSD tab in Betaflight Configurator. Underneath Video Format, guarantee HD is chosen.
Setup DJI Distant Controller
When you’re utilizing a third-party radio hyperlink, you’ll be able to skip this part.
Utilizing DJI’s distant controller eliminates the necessity to wire a separate radio receiver to the flight controller, because the DJI O4 Air Unit additionally serves as an RC hyperlink. This simplifies the setup course of. Nevertheless, there are just a few downsides to think about:
- Primary performance: DJI’s distant controllers lack the superior options and management precision provided by extra subtle methods like ExpressLRS.
- Failsafe dependency: For the reason that video and radio indicators share the identical hyperlink, dropping the video sign additionally leads to a failsafe, which isn’t the case with superior RC hyperlinks like ExpressLRS that usually outperform video hyperlinks considerably.
Suitable DJI Distant Controllers:
- RC2: Works solely with the Goggles 2 and Integra.
- RC3: Works solely with the Goggles 3 and N3.
Pairing the DJI Distant Controller 3:
- Energy in your goggles 3 and RC3.
- Lengthy-press the energy button on each the goggles and distant controller to enter linking mode.
- As soon as the units are efficiently linked:
- The goggles will cease beeping and show the stay view.
- The distant controller will cease beeping.
Configuring Betaflight:
- Within the Ports tab, allow Serial RX for the UART related to the SBUS wire.
- Within the Receiver tab, set the protocol to SBUS (by way of UART).
Movies Recording
The O4 Air Unit has 23GB of onboard reminiscence for recording flight footage. Relying on the decision you choose, it will probably retailer roughly 30 to 45 minutes of recordings. Sadly, it doesn’t assist micro SD playing cards, so be certain to offload footage recurrently; in any other case, the unit would possibly cease recording till you unencumber reminiscence.
You may begin recording through the use of the Document button within the goggles’ high menu. Alternatively, you’ll be able to configure the O4 Air Unit to begin recording routinely whenever you arm the quad within the system menu. Navigate to Settings → Digital camera → Superior Digital camera Settings to allow this selection, which many pilots discover extra handy.
Obtainable Resolutions & Body Charges:
- 4K 60fps
- 4K 50fps
- 4K 30fps
- 1080p 120fps
- 1080p 100fps
- 1080p 60fps
- 1080p 50fps
- 1080p 30fps
Obtain Video
To obtain movies, plug within the USB cable, an exterior drive will seem in your pc, containing all of the recorded footage. To obtain video off the Goggles, it’s best to energy them on first, in any other case connecting the USB cable does nothing.
Video Stabilization
Video stabilization helps clean out flight footage by lowering shakiness and vibrations. The O4 Air Unit helps two stabilization strategies: RockSteady and Gyroflow.
- RockSteady is built-in and may be enabled within the goggles’ menu. It stabilizes footage routinely throughout recording, providing first rate outcomes with minimal effort. To allow RockSteady, set Recording Stabilization to ON.
- Gyroflow is an open-source, software-based stabilization software that gives extra flexibility. It permits you to fine-tune stabilization settings in post-processing. With Gyroflow, the uncooked footage stays unstabilized, providing you with full management over how a lot stabilization to use. To make use of Gyroflow, set Recording Stabilization to OFF.
For greatest outcomes with Gyroflow, use the next settings:
- Facet Ratio: 4:3
- Digital camera FOV: Vast
- Recording Stabilization: OFF
Gyroflow is straightforward to make use of, and I’ve created a tutorial explaining the way it works: https://oscarliang.com/gyroflow/
Easy methods to Keep away from Jello and Vibration
Just like the O3, the O4 digital camera is extremely delicate to vibrations, making it essential to isolate the digital camera from vibration sources or get rid of vibrations altogether.
Keep away from utilizing 24kHz PWM frequency in your ESC settings, as decrease PWM frequencies can improve vibrations and noise. As a substitute, use a larger frequency, equivalent to 48kHz, for optimum efficiency.
Mounting the O4 digital camera instantly on carbon fiber or CNC aluminum is not beneficial, as vibrations can switch instantly from the motors to the digital camera, inflicting jello in your footage. As a substitute, use a comfortable mounting materials that gives vibration dampening. Many new frames embrace silicone or rubber inserts/spacers particularly designed for mounting the O4 FPV cameras, serving to to scale back vibrations considerably.
Greatest O4 Professional Settings
Not like the O4 Air Unit Professional, the usual O4 Air Unit solely helps one colour mode: Regular. There may be no D-Log M mode, which is most well-liked by cinematographers. Whereas this will likely restrict superior colour grading choices, it simplifies the decision-making when selecting the very best settings.
Not like the O4 Air Unit Professional, the O4 Air Unit solely has one colour mode: Regular. There isn’t any D-Log M mode which is most well-liked by cinetographers. However this limitation additionally makes our choice simpler relating to what settings we must always run.
Beneficial Digital camera Settings for the Greatest FPV Expertise (For many who prioritize low latency and don’t care a lot about recording high quality):
- Facet Ratio 4:3
- Video High quality: 1080p 100fps (provides the bottom latency)
- Digital camera FOV: Vast
- Auto ISO Restrict: 6400
- Auto Mode
Beneficial Digital camera Settings for the Greatest HD Recording (For these Utilizing ND filter, Gyroflow stabilization, and Shade grading):
- Facet Ratio 4:3
- Video High quality: 4K 60fps (30fps could be higher for low gentle, however it will probably improve latency, making correct flying tougher.)
- Digital camera FOV: Vast
- Recording Stabilization: OFF
- Sharpness: -2 (you’ll be able to improve sharpness in post-editing if wanted)
- Noise Discount: 0 (or +1 in low-light conditions to scale back noise in darkish areas)
- Digital camera Mode: Handbook
- Shutter Pace: 1/120
- Auto ISO
- Auto ISO Restrict: 200 – (set this as little as attainable to keep away from graininess; nevertheless, too low would possibly make the picture too darkish.)
- White Steadiness: Put White Steadiness on Auto first and see what the system select, then lock in with that worth, so WB is fastened throughout flight
Beneficial Digital camera Settings for First rate HD Recording (For many who want little to no modifying):
- Facet Ratio 4:3
- Video High quality: 4K 60fps
- Digital camera FOV: Regular
- Auto ISO Restrict: Set as little as attainable in your lighting circumstances. If not sure, go away it on the default (6400). Notice that larger ISO could result in grainier pictures in darkish areas, however it ensures visibility.
- Recording Stabilization: ON
- Shade: Regular
- Digital camera Mode: Auto
- White Steadiness: Auto
Beneficial Transmission Settings for Solo Flying
- Race Mode: OFF
- Transmission Energy: Use the best energy stage legally allowed, or simply set it to Auto.
- Channel Mode: Handbook
- Bandwidth: 60MHz (60mbps bitrate)
Beneficial Transmission Settings When Flying with Different Pilots
- When flying with different DJI pilots: Contemplate lowering transmission energy and utilizing smaller bandwidth.
- When flying with pilots utilizing different FPV methods (e.g., Analog, HDZero): Allow Race Mode to scale back interference.
Race Mode
Race Mode is a function designed particularly for FPV racing, out there solely on the DJI Goggles 3 and N3, however not on the Goggles 2 and Integra because of {hardware} limitations. It optimizes the system for low-latency efficiency and minimizes interference in race environments by aligning its channel frequencies to Race band. Right here’s what Race Mode provides:
- Lowest Latency: Race Mode forces the system into 100fps with a 20MHz bandwidth, attaining latency as little as 20ms.
- Channel Alignment: Channels align with commonplace race band frequencies, making it extra suitable with different FPV methods.
- Cleaner Sign: The telemetry hyperlink now operates on the identical static frequency because the video sign, lowering interference with different pilots. When the Air Unit is off, the goggles cease transmitting altogether, permitting pilots to stroll round with out affecting others.
- Commerce-offs: Narrower bandwidth and decrease energy output cut back vary and penetration, making it unsuitable for freestyle, cinematic, or long-range flying. Nevertheless, these limitations are acceptable for racing, which usually happens in open fields.
Warning: Keep away from powering in your Air Unit whereas others are within the air, because it momentarily sweeps throughout the band, doubtlessly inflicting interference for individuals who are nonetheless within the air. For all different kinds of flying, regular mode provides higher RF efficiency.
Transmission Energy Positive Tune
This function permits you to fine-tune the output energy of your VTX by ±1mW to ±7mW to make sure compliance with racing occasion rules. For many customers, this setting isn’t mandatory until you’re attending a regulated racing occasion the place exact energy ranges are required.
Spectator Mode
The Spectator Mode allows you to watch different pilots flying with the O4 Air Unit, however it comes with compatibility limitations:
- Goggles 3 and N3 customers can solely spectate different pilots utilizing G3 and N3.
- Goggles 2 and Integra can solely spectate different pilots utilizing G2 and Integra.
Spectator Mode doesn’t work throughout these two generations, so make sure you’re utilizing the identical technology goggles because the pilot you wish to spectate.
Conclusion
Organising the DJI O4 Lite Air Unit in your FPV drone is easy, particularly when you observe the wiring, mounting, and configuration steps outlined on this information. Whereas the O4 Lite has some limitations in comparison with the O4 Professional, it stays a strong and light-weight possibility for micro FPV drones. Make certain to recurrently offload recorded footage, optimize mounting for the antenna and digital camera, and select a dependable energy supply to make sure the very best efficiency. Completely happy flying!
