TL;DR - vibration problems solved. Look out for new 250 sized APM quads from onDrone.com soon
Well it is confirmed - I have the 250quad bug that seems to be going around at the moment. After building so many big and stable multi-rotors these seem like too much fun. All the APM Arducopter goodness we know and love but in a bite-size go anywhere package. This just opens up a whole new world of possibilities. It also makes for some great FPV flying, ACRO practice and some of those missions you perhaps dont want to risk on the bigger frames.
The first few prototypes suffered the usual small frame problem - vibrations. Stabilize was acceptable but the graphs were way too "hairy". ALT_HOLD and LOITER were horrible as expected. Quad would shoot up 2-3m when ALT_HOLD engaged. Then the version 3 frames arrived with a "clean-dirty" separation. It made all the difference. ALT_HOLD and LOITER instantly became rock solid. AUTO_TUNE did its little dance.
v3 frame with "clean-dirty" vibration isolation:
v2 frame - no vibration isolation:-
(note slight difference in scale)
Specifications of model shown:
- 250 FPVv3 frame
- ArduFlyer 2.5.2 (arducopter v3.1.5)
- u-blox LEA-6H GPS and MAG
- 4x RCTimer 1806 2300KV motor
- 4x 12A ESC SimonK
- 4x 5" carbon prop
- Imago Cobra FPV camera controlled via FrSky channel 8
- 200mW 5.8G AV transmitter
- FrSky X8R 8 channel receiver
- APM power module
- Circular polarized antenna RP-SMA
- AUW without LiPo = 557g
- AUW with 1800mAh 3S = 705g
We should have some ReadyToFly packages of this available in a few weeks at www.ondrone.com
Get in touch if you want more info or a place on the pre-order list
mark@ondrone.com
Photo from onboard Imago Cobra HD FPV camera. Switch between video and photo modes remotely.
Comments
Have you thought of using the Mini APM 2.6 v3 from White spy quads. Thats what I am building now on the same frame. I also found this ( http://www.hobbyking.com/hobbyking/store/__68694__HK_Pilot_Power_VI...) too... APM PM/Distribution board.
I do not know about the sport to UART adapter, but there is another project that takes an arduino nano (i think) and converts mavlink to sport protocol
I was wondering if you can do the same with the FrSky S.Port to UART module. I have a few kicking around but not tried it yet.
http://www.t9hobbysport.com/frsky-s.port-to-uart-converter-with-2-a...
You can also use either a jdrones IO board, or an arduino pro mini to convert ardupilot mavlink telemetry over to frsky telemetry to feed into the D4RII and it will show up on your taranis radio!
I checked out the D4RII. They look perfect. Thanks for the suggestion.
It's clear my admiration for the X8R was blinding me to some of the other receiver models in their range.
D4RII receivers have telemetry and 8 ch ppm.
@Justin
Haven't finalised what receivers and radios we will offer with it. Think we will do a barebones receiver ready version for those that want to choose their own radio, camera and fpv gear.
Isnt the D4R-II 4 channel only, or do you get 8 on PPM? I'm using 8 here - 1 for camera and 7 on APM.
Also thought the D series doesn't have the two way telemetry.
There is definitely some weight to come off from the high current wiring. Needed to be able to swap out ESCs and Motors as had lots of sync issues with the first prototypes.
I have some of the VRBrain 5 micro chips to try. Looking forward to testing those on these frames.
@Glenn
Thanks. Let me know if you spot something suitable.
One thing I'm sold on is replacing the RF telemetry links with bluetooth module. Built into all android phones and laptops so cuts the clutter of USB OTG and RF dongles. Been working really well on this.
As soon as there's a good quality micro gimbal available for one of these, I'll be all over it.
Did you consider using one of the D4R-II recievers and using PPM out of the receiver to further reduce weight and wires? additionally you would save about $10 on the receiver and still get all the same functionality.