filago's blog View Details
Posted by filago | Dec 03, 2018 @ 11:36 PM | 1,242 Views
Here's a way to help land a glider with elevons.

If you quickly raise both elevons to their full up travel, the glider will mostly stop flying forward, and descend very steeply. I'm not sure it's technically the same as spoilers, but it's really effective.

You probably have a lot more up travel than you're using for pitch (Elevator) control, because roll (Aileron) control needs it. This will put it to use.

Here it is in Companion:

  • Create a curve with 0 output except near the -100 input end, as shown
  • Insert a mix line for each elevon to add the curve output, with the Elevator stick as the source, and add a switch to activate it. Note that the source is "Ele" which is the stick value directly, NOT the same as Elevator input created on the input page, "[I2] Ele" in this example. Verify that the elevons go up (not down) when activated. If you need to flip it, you can either change the 1st curve point from (-100,100) to (-100,-100), or change the weight in the new mix lines from +100% to -100%.
  • Optionally, you can add a Special Function which alerts you periodically if you have this landing mode activated. It's probably a good idea, because there's no change in how the glider flies unless you pull the Ele stick way back, and there's a chance you could forget about it and stop the glider when you don't mean to.

The Elevons must go up quickly, before the glider has time to react and pitch way up or do a loop. So when the time comes, be fast to pull the Ele stick all the way back. You may be surprised at how quickly the glider will stop moving forward and float down to land. It works great for me on an Alula, a Zulu, and a 48" wing.

Comments, questions, and corrections are welcome.

- John
Posted by filago | Dec 02, 2018 @ 11:08 PM | 1,343 Views
When slope soaring, do you frequently adjust the trim to keep the glider flying level with neutral Elevator because the lift changes? Then this is for you.

Here's a way to set up the Throttle stick to vary the Elevator down trim. I find this is really handy.

The idea is to first trim the Elevator (using the trim switches) for dead air or minimum lift. This will be the trim when the throttle stick is down. Then at the slope you use the throttle stick to add enough down trim to compensate for whatever lift you're flying in. It's very quick and easy to keep up with changing conditions.

Here it is in Companion:

  • Curve 1 output range goes from 0 to the maximum amount of trim you want. -15 is good for my typical Alula sloping, with a Thr stick range that's comfortable for me. Adjust to suit your needs.
  • Add a line to the Elevator mix which adds the Curve 1 value as controlled by the Thr stick position. Or if your plane has Elevons, add the line to both Elevon mixes.

Simple and effective. Just verify that the Ele moves down when raising the Thr. If you need to flip the direction, change the sign in the curve or the Thr weight.

Note: You could accomplish the same thing without a curve, using Weight and Offset values in the mix lines, and optionally a Global Variable. I prefer to use the curve because it's visual and helps me remember how to change it if needed.

Comments, questions, and corrections are welcome. I'm curious to know if this or something similar is commonly used.

- John
Posted by filago | Dec 01, 2018 @ 08:32 PM | 1,187 Views
This setup provides real-time adjustment of a parameter in flight, and the values are called out as adjustment is made. The parameter may be anything that can use a Global Variable, such as Differential, Rate, or Expo. This can significantly save testing time, as you can try as many different values as you want, without needing to land and edit the program for each change.
  • Don't implement this unless you understand it well enough to own it. I'm sharing what works for me; you may need to adapt it for your model programs.
  • Use only a reasonable range of test values, start flights with a value that you know is OK, and make small changes while testing.

I'll use an example of assigning the S1 knob to adjust Rudder Expo between 20 and 60%.

Here is the setup in Companion. It looks messy, but the explanation afterwards should help to make sense of it.

  • Curve 1 output range is set from 20 to 60.
  • Channel 9 has a single mix line which takes the value from S1 (-100 to +100) and applies Curve 1 to it. The CH9 value will equal the Expo value we want, ranging from 20 to 60.
  • Logical Switch LS1 will turn ON for 0.7 seconds whenever S1 changes. This will be used to trigger the voice callout of the new Expo value. 0.7 seconds is arbitrary, but is about right for me. The duration only determines how fast the voice callout reacts to S1 changes.
  • Special Function SF1 sets Global Variable GV1 to the value of CH9, so GV1 will equal the Expo value we want.
...Continue Reading
Posted by filago | Dec 01, 2018 @ 02:28 PM | 1,031 Views
This post shows a couple of ways to set up a flight timer that automatically pauses between flights, when telemetry inputs aren't available. It uses Tx stick activity to trigger when the timer runs & pauses.

Option A: Instant Run/Pause

  • CH13 is a mix that sums up how far all the self-centering sticks are moved from center. "Function (|x|)" returns the absolute value so the output will be positive in both stick directions. This avoids having stick positions that cancel each other out.
  • Logical Switch L1 is defined to turn ON when any of the sticks defined in CH13 is pushed away from center.
  • Timer 1 is set to run when L1 is ON.
With this setup, Timer 1 will count up when any of the sticks are moved away from center.

Keeping it running during hands-off flight

The timer above will immediately stop during any "hands-off" flying (or "hands-on" flying if the sticks happen to be centered.) It would be handy if we could delay the logical switch from turning off, to keep the timer running for a while when flying with no stick deflection. There is a delay available for logical switches, but it delays the switch turning ON, not OFF.

It is possible get the effect of an OFF-delay by reversing the logic and applying the ON-delay. So if we change the logical switch to be OFF when the sticks are being pushed, and turn ON when the sticks are at center, then it is delayed from indicating that the sticks have returned to...Continue Reading