On this tutorial, I’ll information you thru organising the DJI O4 Lite Air Unit in any FPV drone. This contains wiring it to the flight controller, configuring Betaflight OSD, and sharing helpful suggestions together with the greatest transmission and digital camera settings to realize optimum efficiency on your particular wants.
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The place to Purchase?
You should purchase the DJI O4 Lite Air Unit from the next retailers:
At present, elements are usually not offered individually, that means in the event you break the digital camera or transmission module, you’d have to interchange the complete air unit. Hopefully, spare elements will develop into obtainable sooner or later to make repairs extra inexpensive. Nevertheless, the antenna is well detachable and replaceable.
Mounting
The O4 Lite Air Unit is designed for micro-sized FPV drones, resembling tinywhoop and ultralight quads. Since these small drones sometimes use a flight controller with a 25.5×25.5mm mounting sample, it’s doable to mount the O4 AU straight on prime as a part of a single stack.
Many trendy frames have devoted areas within the rear for mounting the VTX, however this will not all the time work for the O4 Lite resulting from its quick digital camera cable (solely 5cm lengthy).
Picture Credit score: Calpulz
The true problem is mounting the digital camera resulting from its unconventional mounting system. If in case you have entry to a 3D printer, you possibly can design a customized mount on your current 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 that the antenna is securely strapped to one thing like the cover. The antenna is simply friction-fitted, that means the U.FL connector might pop off in a crash.
Disconnecting Digital camera and Antenna
It’s doable to disconnect the digital camera from the transmission module, however the coaxial cable/connectors are glued in place. Until you may reapply the glue after reconnection, I don’t suggest disconnecting them. Eradicating or changing the antenna is simple although.
Powering the O4 Lite
The O4 Air Unit (Lite) could be powered straight from a 1S, 2S, or 3S LiPo battery (3.7–13.2V). Nevertheless, the Air Unit could develop into unreliable and even shut down when the voltage drops under 3.7V. Subsequently, it’s not beneficial to energy the O4 Air Unit straight from a 1S LiPo. As an alternative, energy it from a secure 5V or 9V BEC on the flight controller, which additionally offers extra safety towards voltage spikes.
Energy necessities:
- Max energy consumption: ~6W
- Present draw at 700mW: 5V 1.2A or 9V 0.67A
- Really helpful BEC: Minimal 5V 2A BEC or 9V 1A BEC (If in case you have 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 current DJI Air Models. Nevertheless, you need to all the time 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-obligatory)
In contrast to the O4 Professional, the O4 Lite doesn’t have solder pads. If you wish to solder it on to the flight controller, you’ll need to lower off the connector from the cable and strip the wires.
In case you are not utilizing a DJI Distant to regulate the drone, and are as a substitute utilizing your individual radio receiver, it’s beneficial to take away the SBUS wire (DJI HDL) from the connector. This may stop potential conflicts. Use a pointy software, resembling a pin or needle, to barely raise 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 shouldn’t be required.
Professional Tip: that the O4 Air Unit should be powered by a battery or a accurately rated energy provide throughout activation. In contrast to the O3, it can’t be activated utilizing simply the USB-C cable. Though the USB-C cable shouldn’t be included, any USB-C knowledge cable will work.
Obtain DJI Assistant 2 (Shopper Drone Sequence): https://www.dji.com/nl/downloads/softwares/dji-assistant-2-consumer-drones-series.
If in case you have 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 out there on your O4.
Professional Tip: For firmware updates, you may safely unplug the battery through 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 gained’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 laptop utilizing a USB-C knowledge cable.
- Replace the firmware through 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 → Swap, and choose “DJI O4 Air Unit.”
Enter Bind Mode
- Press and maintain the facility button on the goggles till they begin beeping, indicating they’re in bind mode.
Energy on the O4 Air Unit
- Anticipate 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 strong 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 Models and the Vista system.
Professional Tip: For those who’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 underneath the settings.
Press the hyperlink button between the lenses on the Goggles 2 to enter bind mode.
Energy on the O4 Air Unit and look ahead to the LED to develop into crimson. Press the bind button on the Air Unit. The crimson LED will flash, indicating bind mode. Binding is profitable when the LED turns strong inexperienced, and the digital camera feed seems in your goggles.
Switching Between Professional and Lite
For those who 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 laws), they are going to be restricted by way of output energy (solely 25mW) and channels. There might be just one obtainable channel within the 40MHz mode and three obtainable channels within the 20MHz mode.
In FCC mode, you need to have the utmost 1200mW output energy choice, and there needs to be 7 obtainable channels within the 20MHz mode, and three obtainable channels within the 40MHz and 60MHz mode.
For goggles in CE mode, it’s doable to carry out the “FCC hack” to unlock increased 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 foundation 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, underneath 40MHz or 60MHz bandwidth, you need to see 3 channels obtainable in FCC mode. If it can solely present 1 channel there, you might be in CE mode.
As soon as FCC mode is unlocked, you gained’t need to do it once more. You’ll be able to 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 obtainable OSD components.
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’ve got 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 components all the way in which 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
For those who’re utilizing a third-party radio hyperlink, you may 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 a number of downsides to think about:
- Fundamental performance: DJI’s distant controllers lack the superior options and management precision supplied by extra subtle techniques like ExpressLRS.
- Failsafe dependency: Because the video and radio indicators share the identical hyperlink, shedding the video sign additionally ends in a failsafe, which isn’t the case with superior RC hyperlinks like ExpressLRS that sometimes outperform video hyperlinks considerably.
Appropriate DJI Distant Controllers:
- RC2: Works completely with the Goggles 2 and Integra.
- RC3: Works completely 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 reside 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 (through UART).
Movies Recording
The O4 Air Unit has 23GB of onboard reminiscence for recording flight footage. Relying on the decision you choose, it could possibly retailer roughly 30 to 45 minutes of recordings. Sadly, it doesn’t assist micro SD playing cards, so be certain that to offload footage repeatedly; in any other case, the unit would possibly cease recording till you unencumber reminiscence.
You’ll be able to begin recording by utilizing the Document button within the goggles’ prime menu. Alternatively, you may configure the O4 Air Unit to start out recording mechanically 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.
Accessible 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 laptop, containing all of the recorded footage. To obtain video off the Goggles, you need 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 could be enabled within the goggles’ menu. It stabilizes footage mechanically 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 means that you can fine-tune stabilization settings in post-processing. With Gyroflow, the uncooked footage stays unstabilized, supplying 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: Huge
- 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/
Find out how to Keep away from Jello and Vibration
Much 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 an alternative, use a increased frequency, resembling 48kHz, for optimum efficiency.
Mounting the O4 digital camera straight on carbon fiber or CNC aluminum is not beneficial, as vibrations can switch straight from the motors to the digital camera, inflicting jello in your footage. As an alternative, use a mushy 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 cut back vibrations considerably.
Greatest O4 Professional Settings
In contrast to the O4 Air Unit Professional, the usual O4 Air Unit solely helps one shade mode: Regular. There’s no D-Log M mode, which is most well-liked by cinematographers. Whereas this will restrict superior shade grading choices, it simplifies the decision-making when selecting the very best settings.
In contrast to the O4 Air Unit Professional, the O4 Air Unit solely has one shade mode: Regular. There isn’t any D-Log M mode which is most well-liked by cinetographers. However this limitation additionally makes our resolution simpler on the subject of what settings we must always run.
Really helpful 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 (affords the bottom latency)
- Digital camera FOV: Huge
- Auto ISO Restrict: 6400
- Auto Mode
Really helpful Digital camera Settings for the Greatest HD Recording (For these Utilizing ND filter, Gyroflow stabilization, and Colour grading):
- Facet Ratio 4:3
- Video High quality: 4K 60fps (30fps may be higher for low gentle, however it could possibly improve latency, making correct flying more durable.)
- Digital camera FOV: Huge
- Recording Stabilization: OFF
- Sharpness: -2 (you may improve sharpness in post-editing if wanted)
- Noise Discount: 0 (or +1 in low-light conditions to cut back noise in darkish areas)
- Digital camera Mode: Handbook
- Shutter Pace: 1/120
- Auto ISO
- Auto ISO Restrict: 200 – (set this as little as doable to keep away from graininess; nevertheless, too low would possibly make the picture too darkish.)
- White Stability: Put White Stability on Auto first and see what the system select, then lock in with that worth, so WB is fastened throughout flight
Really helpful Digital camera Settings for Respectable HD Recording (For many who favor little to no enhancing):
- Facet Ratio 4:3
- Video High quality: 4K 60fps
- Digital camera FOV: Regular
- Auto ISO Restrict: Set as little as doable on your lighting circumstances. If uncertain, go away it on the default (6400). Observe that increased ISO could result in grainier pictures in darkish areas, nevertheless it ensures visibility.
- Recording Stabilization: ON
- Colour: Regular
- Digital camera Mode: Auto
- White Stability: Auto
Really helpful Transmission Settings for Solo Flying
- Race Mode: OFF
- Transmission Energy: Use the very best energy degree legally allowed, or simply set it to Auto.
- Channel Mode: Handbook
- Bandwidth: 60MHz (60mbps bitrate)
Really helpful 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 techniques (e.g., Analog, HDZero): Allow Race Mode to cut back interference.
Race Mode
Race Mode is a characteristic designed particularly for FPV racing, obtainable solely on the DJI Goggles 3 and N3, however not on the Goggles 2 and Integra resulting from {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 affords:
- Lowest Latency: Race Mode forces the system into 100fps with a 20MHz bandwidth, reaching latency as little as 20ms.
- Channel Alignment: Channels align with customary race band frequencies, making it extra appropriate with different FPV techniques.
- 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 generally 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, probably inflicting interference for many who are nonetheless within the air. For all different varieties of flying, regular mode affords higher RF efficiency.
Transmission Energy Superb Tune
This characteristic means that you can fine-tune the output energy of your VTX by ±1mW to ±7mW to make sure compliance with racing occasion laws. For many customers, this setting isn’t obligatory except you’re attending a regulated racing occasion the place exact energy ranges are required.
Spectator Mode
The Spectator Mode helps you to watch different pilots flying with the O4 Air Unit, nevertheless 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 need to spectate.
Conclusion
Establishing the DJI O4 Lite Air Unit on your FPV drone is simple, particularly in the event 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 robust and light-weight choice for micro FPV drones. Be certain that to repeatedly offload recorded footage, optimize mounting for the antenna and digital camera, and select a dependable energy supply to make sure the very best efficiency. Joyful flying!