XR-61: Completed and Maiden Flight

I did the maiden flight yesterday. The plane flies beautifully, but I had some radio issues so I had to cut the flying session short.

 

Precision Aerobatics XR-61 - Unboxing and Build Pictures

I have a new plane that I've been working on finishing up for flight. It's called the XR-61 from Precision Aerobatics, who is known for building extremely lightweight airframes which excel at 3D maneuvers.

I have two of their other planes, the Electric Shock, and the Katana MD, both of which got a ton of use and fly very well. The XR-61 is a bit bigger than either of those, with a 61" wingspan. It's supposed to be a fantastic plane to be able to mix 3D and precision/pattern type flying. I'm really looking forward to it, as it's been a few years since I've done any real aerobatics. I'm going to try using low rates and possible mid rates with this plane to more properly fly different types of aerobatics. In the past, I only ever used high rates, and I have a feeling that my precision flying suffered some from that.

I bought the ARF with the iPAs power package, which includes the servos, motor, ESC, and prop. I also bought the "bling package" which includes a carbon fiber spinner, carbon fiber wheel pants, carbon fiber vortex generator kit, carbon fiber servo arm extensions, and wing bags. I also added a prop protection sleeve because the Vox prop is wood and is prone to damage.

Here are some pictures from the build process:

Wing Bags

Unboxing

Carbon Fiber Spinner

All the Goodies!

Control Horn Work

Carbon Fiber Wheel Pants

Fiberglassing the Motor Mount

Motor Box Installed with ESC and Motor

Tape holding the Horizontal Stabilizer Parallel with the
Wing Tube while the Epoxy Sets

Finished Landing Gear and Landing Gear Cuffs

Control Repeater Upgrades (Again)

After using the upgraded control repeater a few times, it became apparent that having a power switch would be really useful, especially when doing the short flights with the Mojo.

I added a switch next to the model select switch, so instead of opening the lid and unplugging the battery, I can just quickly switch it off.

In addition, I added a voltage monitor/alarm which is easily visible through the top of the case. This is a good way to ensure the battery that's powering the ground station has plenty of life left, without having to use the telemetry cable from the repeater receivers.

Control Repeater Upgrades

Now that I have two models being flown with Dragon Link (the Sabre and the Mojo), I realized that there is a complication with the control system. The reason for the complication is that the repeater receiver must be bound to selected model in the DX20, and it must have failsafe programmed correctly.

For the Sabre, this means that the repeater receiver must be programmed to engage return to home, which means the equivalent of the top two right switches on the DX20 are "down."

For the Vortex, since it does not have a return to home, the desired failsafe is to simply cut the throttle. In this case, that means the top two right switches must be "up" (opposite the failsafe position for the Sabre).

The switch positions that cut the throttle in the Mojo and that engage return to home in the Sabre are arbitrary, but that's how I have them set up and how I am used to them.

I had three options to remedy the failsafe issue for two models:

1) Rebind, reprogram failsafe, and re-test failsafe (turn off DX20 and see what happens) every time I switch models.

2) Reprogram the switch positions on one of the two model programs in the DX20, to ensure that the desired failsafe behavior results are trigger the same for each model (Would require overriding Model Match in the DX20).

3) Use two repeater receivers, one for each model, and switch receivers when switching models.

I didn't choose number one because it's hugely inconvenient and prone to messing up the failsafe programming, resulting in potentially unsafe conditions during the necessary failsafe test. I didn't want to do two either because it is also hugely inconvenient, but I also am very used to the way the two switches are used in each model. Changing the switch positions would slow down my reaction in the event of an emergency and could cause problems.

I chose number 3. It may seem more clumsy than necessary, but I think I made it pretty convenient with my setup. I also chose to "package" all the gear in the repeater ground station in a much nicer and more durable way than the previous foam board version. (I used some foam board, but more for convenience than for structure.)

I used a DPDT (double-pole, double-throw) switch and completely rewired the whole ground station. Now, when choosing a model, I simply plug the battery in to the BEC, which powers the Dragon Link transmitter, and then use the switch to pick which model I am flying. The switch directs power from the BEC to the correct receiver, and directs the SBUS control signal from the correct receiver to the input of the Dragon Link transmitter.

The case I found at Target is the perfect size for this application because I was able to get all the electronics in one side, and leave the perfect space on the other side for the battery that powers the whole ground station. On top of that, the whole thing fits perfectly in my DX20 case.

Here are some pictures from the build:

Completed with the Lid in Place, 2S, 5000mAh Lipo Installed

The Lid Removed, Power Cable (Deans), Telemetry Cables

The Foam Board Cover Removed, Revealing a Bit of Wiring,
the DPDT Switch, the Two Receivers, and the BEC

Model Select Switch

New Repeater Station in the DX20 Case

Bench Testing the New Wiring (1 of 2)

Bench Testing the New Wiring (2 of 2)

Mojo, Kenney Field

I flew another 5 (only 4 videos because I forgot to start recording once) flights in the Mojo yesterday. It was a cool and breezy day, but it was really fun, thanks to being able to fly from the car with the control repeater setup. For the last flight, I decided to take off from the moon roof of my car, just for something interesting.

Vortex 230 Mojo, Westwood Park

More onboard videos with the Mojo and the GoPro. I changed the GoPro from 30 frames per second to 60, and the videos came out noticeably better, including seemingly less jello. There are only a few places where I notice it, and it's not enough to detract from the video. I'm pretty happy with the camera so far. I'm getting more confident with flying the Mojo as well. I had a couple close calls with trees, but for medium speed cruising, I've gotten much smoother at coordinating the yaw and roll together. This is most noticeable in video 2 of 3.

Vortex 230 Mojo, GoPro

I did some more flights today with the Mojo. For the first time, I put my GoPro on board and flew with that. There is some jello in the video at certain throttles. I'm not sure what's causing that, but it isn't terrible. The picture is noticeable better than the Mobius, but I think I will use 60 frames per second from now on. It will result in much larger file sizes, but the video will be much smoother and more enjoyable to watch.

I'm glad I have Dragon Link installed in the Mojo, because I was able to set up my control repeater on the hood of my car, and fly from the driver's seat. Otherwise, I wouldn't have even flown, as it's still only about 35 degrees and breezy, which is just way too cold for comfort.

Here are the two videos:

Vortex 230 Mojo, Dragon Link

I received and installed the Dragon Link Nano receiver in my quad. This enables basically unlimited range, which is unnecessary on a small race style quad, but it ensures that I won't ever get drop outs when I'm flying around obstacles, or if I do feel like pushing it out a mile or so.

I got some flights in after the installation. It is very difficult to fly in a tight area like in these videos. I need a lot of practice to gain some confidence for getting closer to obstacles. I also noticed that the video performance was quite bad. A higher gain receiver antenna will definitely help in the future.

Here's how I mounted the Dragon Link receiver antennas.

Here's the receiver installed inside.

System Level Schematic

I thought it would be interesting to look at a "map" of all the communications that are set up and operating with my current FPV setup on the Sabre.

Note that this does not include the tBeacon or HAM radio. These are only ever going to be used to find the plane in the event that it goes down, and wouldn't add much value to this diagram.

Note: It makes the most sense to start with the orange 2.4 GHz transmitter, and then work your way around.

Sabre: New Photos Inside the Fuselage

Since the installation of the tBeacon and camera switcher, I decided to take some photos to show the electronics section of the Sabre.

These photos are taken through the opening in the top of the fuselage directly below where the wing attaches, behind where the flight battery sits.

Electronics with Labels

Electronics

Sabre: Camera Switcher Update, Belly Camera

I realized that it would be very easy and straightforward to add a third camera to the Sabre. The camera switcher is 3 position, I have a 3rd FPV camera, and the Sabre already has a spot to put a camera in the belly. I used my Runcam PZ0420H CCD camera in the recess in the belly of the Sabre.

To do this, all I had to do was make a small hole to route the wires up to the electronics section, to plug into the camera switcher.

I used Velcro to secure the camera.

Paper towels were used to snug the fit to help prevent vibration or dislodging.

I made a simple cardboard cover. Packaging tape holds it in place.

Updated Ground Station Schematic

I updated the ground station schematic to the most recent actual configuration.

I also added dashed lines to indicate where there are options.

Equipment as it is Presently Configured. Dashed lines indicate optional connections.

Sabre Airborne Equipment Schematic, Updated

This version reflects the following changes:

1. Change BEC power input from main battery balance lead to Micro Deans, tapped off of main discharge lead.
2. Addition of camera #3.
3. Rewire camera switcher to receive power from Vector.

1.2/1.3 GHz Ground Station Complete

Updated 3/7/18: Added V2 picture with labels.

I now have installed the latest round of equipment on my ground station, and set it up for diversity. With the latest changes, I now consider my ground station done and ready for use for flying in the spring. I can still add the Lumnier monitor somewhere on the tripod, but it is just as easy to use as a standalone unit.

All of the gear is mounted to back the Crosshair antenna with Velcro. It took several iterations to get everything to just fit without interfering with the tripod.



V1: Component Labels

 

V2: Some Subtle rearranging and neatening of the layout.

 

tBeacon Complete and Installed

I now have finished final "assembly" and installation of the tBeacon. You can't see it, but in order to route the tBeacon's antenna as vertically as possible (for maximum signal), I put inside a straw and routed it down the start of the wire channels in the tail boom. The antenna is probably about 30 degrees off from vertical now.

I soldered the wire harness that I planned out by the previous post.

I had to solder the tBeacon's included 50mAh lipo battery to the circuit board terminals. I then put shrink wrap over the assembly.

Custom Harness

tBeacon with Battery Soldered

Completed with the Shrink Wrap

Installed. In this picture, the tBeacon's antenna runs down and to the right.

tBeacon Progress

I've made some progress with getting the tBeacon GPS tracker ready to install. It's not particularly laborious, I just haven't spent much time on it.

I was able to upgrade firmware, set parameters to maximum battery life, and calibrate it to my HAM radio's calling tone.

I am now ready to solder the wire harness to connect it all together with the Vector (which is also connected to the Dragon Link receiver). I made this crude (not to scale) diagram with correctly colored wires so I don't have to re-figure it out when I am soldering.

Taranis Progress, Custom Sounds and Images

I've been spending a lot of time researching resources and learning the Taranis. I was able to update to Open-Tx 2.2.1 and flew my Vortex 230 for 3 flights a few days ago.

Since then, I've spent some time adding custom sounds and custom images.

Here's the custom image set up on the model screen.

It is pretty neat and rewarding, because it takes some discipline to understand it well enough to get it to work.

Here are some of the links (not exhaustive) I've used along the way so far:

Video Playlist: Project Blue Falcon's Taranis X9D Videos

Video: Upgrading Firmware

Video: Upgrading Bootloader

Video: Binding XSR Receiver

Open-Tx Online Manual

Written Instructions for Setting Volume Control on a Knob

Written Instructions for Playing Music

Written Instructions for Custom Sounds

Download Link to TTSAutomate

Video: Instructions for Using TTSAutomate for Custom Sounds

Video: Instructions for Creating Custom Spalsh Screen and Model Images

New FPV Gear, Pictures

I recently posted about updates to the Sabre, and to my FPV ground station. Well, the equipment has arrived:

Here's what I have now:

1. tBeacon Amber
2. Handheld HAM radio (Baofeng UV-5R V2+)
3. Micro FPV Camera (Caddx SDR1) (Covered here.)
4. Camera Switcher (from GetFPV) (Covered here.)
5. Diversity
1. Eagle Eyes ground station module
2. Second video receiver (ReadyMadeRC 900 - 1.3 GHz)
6. External FPV Monitor (Lumenier 7" with DVR, 5.8 GHz receivers and diversity)

As always, more updates will follow. For now, here are some pictures.

tBeacon Amber

tBeacon Amber, Wire Harness, Stickers

HAM Radio, Baofeng UV-5R V2+

Eagle Eyes Module

Lumenier 7" Monitor