I actually like the straightforward design of the HGLRC Draknight O4, however the digicam gentle mounting simply doesn’t appear to work correctly and introduces jello/vibration into the video. That could be a main downside on this quad, and sadly it actually hurts the general expertise. Let’s take a more in-depth look on this evaluate.
What different O4 micro quads do I like to recommend? Take a look at this purchaser’s information: https://oscarliang.com/micro-drone-dji-o4-lite-comparison/
The place to Purchase
Product Web page:
Comes with These Equipment:
- 8x GF2023 propellers (2 units)
- 2x LiPo straps
- 4x rubber grommets for the O4 Air Unit
Specs
- Body: Draknight 2 Inch O4 Model
- Stack: HGLRC SPECTER 15A ELRS AIO
- MCU: STM32F411
- Gyro: MPU6000
- FC Firmware: ZEUSF4EVO
- ESC Firmware: Q-H-50 (Bluejay)
- Digicam/VTX: DJI O4 Air Unit
- Motors: HGLRC SPECTER 1003 10000KV
- Propellers: GF2023
- Non-compulsory Receiver: ELRS 2.4G / TBS Nano 915MHz
- Wheelbase: 93mm
- General Dimensions: 80 × 88mm
- Weight:
- With out battery: 61.9g
- With 2S 750mAh LiHV: 97.2g
Design
The body itself is straightforward to construct and preserve. You solely must take away 4 screws to take off the highest cage and entry the electronics inside.
The soft-mounting platform is sort of distinctive — I’ve by no means seen this design earlier than. The digicam cage is separated from the principle body and linked by a TPU half that acts as a vibration dampener. This permits the digicam cage to maneuver up and down, left and proper, and you may even twist it by hand.
There may be additionally a devoted TPU mount on high of the body for putting in a GPS module, though GPS isn’t included. Nevertheless, the FC solely has two UARTs: one is utilized by the ELRS receiver, and the opposite is for the DJI O4. So there actually isn’t any UART left for GPS. SoftSerial is feasible for GPS, however I’d not suggest it as a result of it isn’t quick sufficient and is unlikely to be dependable for Rescue mode.
There may be additionally a rear spoiler created from 3D-printed TPU. I’m not positive if it really does something aside from including a little bit of weight and drag, nevertheless it does look cool.
The Draknight O4 has an onboard buzzer/LED board on the rear. The LEDs could be configured within the Betaflight LED tab for various capabilities, equivalent to warnings or altering with throttle degree. By default, they only present a blue gentle. They’re very brilliant, and you may see the quad fairly properly at evening.
The buzzer, alternatively, is slightly disappointing. It is extremely quiet, nearly as quiet because the motors utilizing DShot beacon.
There’s a small 16V 100uF capacitor soldered to the facility enter for noise filtering. For my part, that could be a bit too small. Personally, I’d have used 220uF minimal for a 2-inch quad. For capacitor suggestions: https://oscarliang.com/capacitors-mini-quad/
It runs props out, and the propellers are friction-fit, so no mounting screws are required.
Putting in the DJI O4 Air Unit
Mine didn’t include the DJI O4, so I needed to set up my very own.
You’ll need the unique digicam adapter that got here with the O4 in an effort to set up the digicam on this drone.
Observe that it doesn’t include a cable, so you must use your personal. The FC additionally doesn’t have a connector for the O4, so you will want to chop the cable and solder it on to the FC. Barely annoying — I actually want HGLRC had pre-soldered the cable to the FC so customers might simply plug it in.
In terms of soldering, it isn’t the best job as a result of the solder pads are fairly tiny. If you’re not assured with soldering, get the pre-installed O4 model as an alternative.
At the very least the Ports tab and OSD are already configured out of the field for the DJI O4, which is a pleasant bonus.
HGLRC recommends powering the DJI O4 instantly from the battery, in all probability as a result of the onboard 5V BEC isn’t highly effective sufficient, so I soldered the O4 energy to the battery lead pads.
Jello Difficulty and Flight Efficiency
The soft-mounting platform for the digicam is an attention-grabbing thought, however in my expertise it doesn’t work properly.
It is just too versatile. The digicam can transfer in all instructions, which creates vibration and jello that’s noticeable even within the goggles. Making use of Gyroflow to the recording doesn’t assist in any respect — in some instances, it really makes it look worse. If you wish to produce cinematic footage, that is simply not usable.
I’m not positive if HGLRC actually examined this correctly earlier than manufacturing. I’ve seen a variety of complaints on-line describing the very same jello situation, so this clearly seems to be like a design flaw quite than an remoted case.
If you happen to ignore the jello, the quad is definitely fairly fulfilling to fly. It handles properly, feels responsive, and stays properly locked in. It’s not very highly effective, however it may well nonetheless do most simple freestyle strikes, which is precisely what you need for ripping round small parks and flying by tight gaps. If you happen to fly over grass fields like I do, this quad can take a beating and really makes a good observe quad too.
It’s a disgrace the jello ruins the expertise, as a result of because it stands, I can’t suggest this quad attributable to that situation.
Some extra flight stats:
- It hovers at round 30% throttle
- 2S 550mAh: 3–4 minutes
- 2S 750mAh: 5–6 minutes
- 2S 850mAh: 6–7 minutes
Yet one more factor to notice: the props can come free over time as a result of they’re solely friction-fit, so make certain to push all of them the best way on earlier than each flight.
PID and Filter Tune
It comes with a customized tune, however it is extremely conservative. Filters are largely near default values, and the PID values are fairly low for a 2-inch quad. There may be positively room for enchancment.
There may be 8MB of flash reminiscence for Blackbox logging, so you’ll be able to tune it in order for you. Listed here are my tuning tutorial: https://oscarliang.com/pid-filter-tuning-blackbox/
Tips on how to Setup
Firmware:
- The FC goal is ZEUSF4EVO, and it got here loaded with Betaflight 4.5.2. The unique CLI diff could be discovered right here.
- ESC firmware is Bluejay, 0.19, 48kHz (Q-H-50).
- Onboard ExpressLRS receiver: HGLRC Hermes 2.4GHz (Firmware 3.2.1).
- Propellers mounting: motors are reversed route.
To setup for first flight, I did the next:
- Bind ELRS Receiver: Plug within the USB cable to the flight controller, the onboard ELRS receiver will go into WiFi mode after ready a minute. Be part of the WiFi community “ExpressLRS_RX”, go to 10.0.0.10 in your browser, and enter bind phrase. And binding was accomplished. For extra element: https://oscarliang.com/bind-expresslrs-receivers/#Methodology-3-Coming into-Bind-Phrase-in-Internet-UI
- Pair O4 to Goggles 3:
- Presets tab: make a backup of the present settings (press the Backup button); Load ExpressLRS preset primarily based in your ELRS packet charges, do: https://oscarliang.com/rc-link-preset-betaflight/
- Receiver tab: allow Telemetry
- Modes tab in Betaflight Configurator: Configure the switches for arming, angle mode, beeper, and turtle mode.
- OSD tab: choose HD Video Format, and cargo my CLI settings: https://oscarliang.com/betaflight-osd/#HD-without-GPS.
- PID Tuning tab: set your personal charges, right here’s my charges: https://oscarliang.com/charges/#My-Charges
Conclusion
The HGLRC Draknight O4 has so much going for it on paper. It’s light-weight, easy, simple to take care of, and really flies fairly properly for a sub-100g micro quad. Sadly, the digicam soft-mount design is essentially flawed and causes critical jello within the footage.
That could be a large drawback on a quad constructed across the DJI O4 Air Unit, as a result of good video high quality is likely one of the principal causes to purchase it within the first place.
If HGLRC redesigns the digicam mount, this might change into a really stable little quad. However in its present kind, I can’t suggest it.
