SEN 2681 - Reading the Sporting Code while sitting on the Geo Fence

SEN 2681

Reading the Sporting Code while sitting on the Geo Fence

1. Closed Loop controls and the Sporting Code
2. Flying wing
3. Geo Fencing

Closed Loop controls and the Sporting Code

From:Ian Kaynes
Closed Loop controls

It is probably worth reminding readers of the relevant parts of the model definition from the Sporting Code:

B 1.1 General definition


d) Free flight model aircraft must be launched by the flier, and must not be equipped with any device that allows them to be flown automatically to a selected location or controlled remotely during the flight other than to stop the motor and/or to terminate the flight.


B.1.2.1 Free Flight:

a) This is a flight during which there exists no physical connection between the model aircraft and the competitor or his helper. Radio control functions are allowed only when specifically stated in the rules for the relevant class. Closed loop control systems with active sensors and operating aerodynamic flight controls or moving mass are not allowed, unless allowed in the class rules.

b) Unless specified otherwise in the rules for a particular class, Free Flight models must be launched with at least one hand holding the fuselage of the model.


And in F1E class rules:

3.5.1 includes : The glider can be equipped with a steering device, which may use a direction sensor and measurement of flight time. The steering device must not use any measurement of geographical location and must not be controlled remotely during the flight.


So, in reply to Dick Ivers' point, while motor control might be closed loop it is within the motor system, it is not controlling the aircraft by operating an aerodynamic control or moving mass

And in reply to your editorial comment, GPS is ruled out but any other form of magnetic or electronic sensing of direction is allowed. What constitutes a steering device is an open choice.

Ian Kaynes

Flying wing

From:gilbert morris A short while ago I predicted that F1C would go tailless, but in so doing I
was counting on gyroscope aileron control since high performance flying
wings are so inherently unstable as to be useless for FAI competition. This
prediction is in conflict with the no feedback rule. So too is the
consideration of parachute DT for flyoffs. Back to the building board!

Geo Fencing ?

From:Michael Achterberg


Just curious. Could a closed loop system with a geo map similar to Aloft model make a freeflight glide into the wind once it reaches a preprogrammed  field size?? Wouldn't something like this fix small field criteria??Is this a possibility down the road? Not the thermal part, but just directional. Dino....

Editor and Magic Timers comment
Dino, what you are talking about is a form of Geo Fencing, this is used in some instances in conventional R/C and more common with Drones.
For R/C training you specify that the model must remain in pre-determined “box’ in the sky, the beginning flyer controls the model normally but if it flys too close to the ground or too far away it is brought back into line.
With Drones geo fencing is used to keep the drone either in a restricted area or out of a restricted area.
In our case we could for example D/T the airplane if it flew off the field. The field could be described as a set of coordinates out lining a square or even a box such that you D/T’d the model sooner if it was higher. The coordinates could be adjusted (by the organizer) based of wind speed and direction.
There are two issues with controlling the direction of the model if it crosses the geo fence. The first is free flight models are notoriously difficult to “radio” or in this case automatically control the direction because our control surfaces are not designed to do that and we have tricks such as wing warps that are designed to keep the model in a thermal and are not directly connect to a control surface. The second is steering the model opens opportunities for someone intentionally unfairly affecting the results (also known as cheating).
Doing something like this requires the use of a Standard or Certified geo fencing system so that every one is treated the same way, the FAI does a have a method for certifying and is used in some R/C events and F1Q and altimeter timing . It also must have a way of adjusting the fence coordinates easily during a contest. Think of a World Champs with 100 participants in an event each with up to 4 models he may fly in a round. A possible approach could be combining this with an on board, automatic reporting flight timing device, that could for example set the fence coordinates from data in the organizer’s base station at the moment the flight commences.
The technology to do this is all “there” today, the onboard electronics in advanced hobby (and professional) drones has this, and more that we don’t need, many of the electronic timers that we use have major parts of this. This has a place in some forms of free flight but not all. The packaging of this technology in a size, weight, usability and cost is a challenge along with a way to coordinate our traditional rule making process along modern innovation processes need to get something like this done.