FPV, Going digital! My experience with Walksnail Avatar gear

[LitterBug]

Hi All!
Long time analog FPV flyer here and I have been keeping tabs on a few of the digital FPV platforms out there as they have matured. I have finally broken down and jumped into the game myself, and am going down the CaddxFPV Walksnail Avatar path. The two others I had considered were DJI, and RunCam Zero. Not going to be covering those, but will document the setup of the Walksnail gear.

Cheers!
LitterBug

 

[LitterBug]

I picked up the Walksnail VRX for my ground station, and a handful of cameras. I will be continuing to use my existing Goggles with the VRX plugged in to the HDMI port rather than a analog RX plugged in to the old port or using the internal RX.

Step 1
Any time I get new hardware (sometimes even before) I download all the manuals and firmware updates. No use finding a bug that has already been solved. For Caddx, the firmware link is right next to the walnut action camera I've been using and the walksnail gear. So as luck would have it, yesterday, the firmware version was 37.42.5 and I got it all downloaded and everything updated. Today, they sent an email about a "new release!". Sweet! I get to practice it again with 38.43.4!

After downloading the .zip file, unpack it and there is an image showing which file in the firmware directory goes with which device.

Sky is for Camera devices, Gnd is for receivers/goggles.

So in my case, the AvatarSE_Gnd_38.43.4.img gets copied to the VRX ground reciever, and the Avatar_Sky_38.43.4.img is copied to the cameras.

The basic upgrade procedure is to copy the right .img file to the internal storage of each device, Power the device up, and then hold the "bind/link" button for 8 seconds till the update starts. For devices with an SD card, You can mount the SD card up on a PC/laptop, copy the file(s) to the root directory, and then put the SD card back into the device. For cameras with built in storage, you must power the camera up, plug the USB cable into a computer, then copy the file(s) to the camera.

Off to get to the latest patchset!

LB

 

[Bricks]

I have been reading and checking things out about digital but I am looking more at the HDZERO, open source, look at what has been done with OT Transmitter. Not ready to make any changes yet but am following closely to see where it really goes.

 

[LitterBug]

I have been reading and checking things out about digital but I am looking more at the HDZERO, open source, look at what has been done with OT Transmitter. Not ready to make any changes yet but am following closely to see where it really goes.

I have been holding back and watching the progression too. With FC OSD integration to all the major firmwares that I fly, reduced costs, and somewhat stability and similar feature sets, I went with what fits my budget, flying style, and mindset. (heavily weighted bang for the buck) Really no wrong path to go between the three main options. Each has it's strength and weakness. My last real hiccup is not wanting to upgrade everything. My fleet is just too big, and the expense is still not cheap. I know it will be tough flying SD/analog after experiencing HD/digital. I will make some sort of pod that will be easily transferred between birds to be able to get it on more things. I have one of the cheapest 1S cameras to throw around on stuff like my FT Tiny Trainer off a 5V BEC. (the 1S cam can technically go up to 3S) Lot's of fun to come!

 

[LitterBug]

I have been bench testing my ground station setup. I picked up a "cheap" 12" 1080P IPS HDMI monitor for my passengers on the ground and a powered HDMI splitter to run the display and my goggles at the same time. Checked for latency of all the components end to end and there is no appreciable latency. Hooked up a VTX/camera to a FC running INAV, and played around with the OSD. Everything is working nice and slick. Just need to get some birds wired up and hit the field now.

 

[Bricks]

Way to go Litterbug sounds like your getting everything worked out, give yourself a pat on the back for job well done.

 

[LitterBug]

Going to add a HD VTX header to a few of my older builds that didn't come with a jack, but have a free serial port. Ordered and received an Adafruit 4208 10 pack of JST-SH 4-pin right angle connectors.
First up will most likely be my ZOHD Drift with a BrainFPV Radix Li Wpb. No switched VTX power. Will probably just plug VTX in when ready to launch.

 

[Bricks]

I sure wish I had yooooour talent when it comes to electronics, something mechanical I m good.

 

[LitterBug]

I sure wish I had yooooour talent when it comes to electronics, something mechanical I m good.

Been playing with electricity, electronics, and computers for half a century. One of the things my Dad and I shared. He always wanted to get into RC planes, but that never happened. I finally got hooked and into RC flying thanks to Flite Test. He always liked me sharing my flying escapades.

 

[LitterBug]

Soldered up wires to one of the sockets. Just need to solder to V+ GND TX RX and all will be ready to go on the Drift to plug in the walksnail VTX.

 

[LitterBug]

Been doing more bench testing of the Walksnail gear connected to my old BrainFPV Radix Li WPB 20x20 stack in the ZOHD Drift. Using Serial6 did not work, but after switching to Serial1, the OSD is functioning correctly! SWEET! Will post flight video as soon as weather and schedule permit! SUPER Stoked to fly HD FPV!

 

[LitterBug]

Decided to take the next step and upgrade my old Fat Shark Transformer Goggles to the Walksnail Avatar GogglesX. My old goggles forced me to switch housings to use the HDMI input, but my old eyes were having trouble focusing without having any adjustments.

I Picked up the GogglesX on a 10% Labor day sale, so that helped push my decision. They have individual adjustments for diopter and focus for each eye. The goggles can do analog in which will allow me to continue using all my analog gear with my existing analog ground station( 1.3 & 5.8 ghz) They also have both HDMI In & Out. So I can run a cable out to a 12" HDMI monitor for my passengers to watch, OR I can also use another digital RX ground station like the VRX I already have, or even use them as a monitor for my flight sims.

Already had all the Firmware update files (Caddx bundels it in one package for all Avatar devices) and have it ready to go.

Cheers!
LitterBug

 

[LitterBug]

Finally got out to the field with the Avatar gear. Quickly realized I should have used a faster plane. The super slow ZOHD drift on 2S was great for looking around, but was not great for chasing other planes at the field and is not a freestyle flyer by any means. One of the guys at the field was flying his plane at full flaps so I could chase him, and at one point was flying 3RD person view from the 12" monitor that I had hooked to my goggles for passenger view. I was also able to proximity fly the trees around the field and test out the range a bit. Flew close to an hour on a 2S Li-Ion pack. Thought I had bumped it up to 200mw, but first flight was only 25mw. Still got decent range, but not great treeline penetration at that power level. 200mw was a good improvement for the range I normally fly. This is a screenshot taken from the goggle's DVR flying at dusk @300'. The Camera/transmitter was one of the cheapest, lightest, 1S, nano cameras, and the quality is still solid. I'll post up video once the film gets developed.

Cheers!
LitterBug

 

[LitterBug]

300' view around the area I fly, then diving into some proximity flying around the trees at the parimeter of the field. Video is from the Goggle's DVR so you see the same quality I get in the goggles but without the OSD overlay.

Make sure to force YouTube to 1080p60. It tends to default to lower resolutions.

LB

 

[LitterBug]

Working on some FC --> HD VTX adapter harnesses and a JST power only adapter so I can get HD on more stuff.

Testing my cheapest VTX which is 1S capable. A 12V squirrel cage fan running on 2s is a quiet way to keep it cool while it is not in the air

 

[LitterBug]

Got the analog gear out and the pigtail in to the StratoSurfer. Configuring the OSD screens, then just need to mount the HD gear and button it up.

I was pleasantly surprised at how easy it was to switch from the internal Analog OSD to the digital gear. Unplugged the camera from the FC, The VTX from the FC, Plugged the pigtail in to a serial port, ground, and Video power.

I have a Matek F405-wing running Ardupilot Plane V4.3.1 from early last year. Haven't touched it with the configurator in a long time and was greeted by a message stating 4.5.6 is the current version. Made me wonder if I was at a high enough release to support HD OSD, but after plugging in and configuring a small number of parameters, everything is working fine.

The pigtails I made are only four wires.
Black - Gnd
Red - VTX power
White - TX (serial 5)
Green - RX (serial 5)

Only 3 Ardupilot parameters to change to make the switch:
OSD_TYPE = 5 (msp displayport)
SERIAL5_BAUD = 115200
SERIAL5_PROTOCOL 42 (Displayport)

Reboot the FC, and then use the configurator to drag/drop display fields where I want them and reboot one more time.

Cheers!
LitterBug

 

[LitterBug]

Flying the Stratosurfer tonight at dusk with the new FPV Gear

 

[LitterBug]

I added a pan servo to the StratoSurfer when setting up the HD FPV pod. Unfortunately, it only had 90 degree movement. I ordered resistors to modify the servo for 180 degree+ pan and the came in today. Funny thing is, resistors are so cheap, it was hard to order in a quantity less than 100. Finally found one with qty 10, and I recieved 20 when they came today. LOL! here is a short clip of the before. 45 degrees on each side:

Really not that usefull. I will show a pic with the 1% 2.2k resistors installed in the servo later, and a clip with the new range of motion. I have measured the actual resistance and they are a matched pair at 2.21k.

Cheers!
LitterBug

 

[Bricks]

Looks like your getting this HD FPV nailed down.

 

[LitterBug]

A little update, I have not yet modded my pan servo but have managed to eek out 180 degrees of rotation from ArduPilot using a different Servo#_Function which scales the output between the Servo#_min and Servo#_max values.

SERVO7_FUNCTION,148 <--- servo Scaling of RC in 9 rather than direct passthrough.
SERVO7_MAX,2500
SERVO7_MIN,500

I will still mod the servo so I can look behind too.