baronbrian

My Feedback: (13)

Reading the rules it doesn't look to me that a governor would be illegal...

rm

My Feedback: (27)

I'd really enjoy watching someone use a heli governor at a contest.

apereira

The governor function will never be usable, the aircraft has to maintain constant speed, that is not possible to achieve with a constant motor RPM, unless it is used for something not pattern related.

cmoulder

And even then what would be required is constant ground speed, not constant air speed....

The more you think about it the ridiculouser it gets.

cartercg

Hi, the ability to set the a specific motor RPM with the throttle stick could be beneficial as it would enable the same motor speed to be reached for the same stick position regardless of the battery voltage and model attitude and airspeed. Hacker were playing with this (a complete new type of controller):

http://www.hacker-motor.com/en/news/54/index.html

but I don't know if anything came of it. The pilot would still need to adjust the throttle stick position to set the right motor RPM to obtain the desired air/ground speed. The pilot would still have to continuopusly adjust the throttle setting to achieve constant speed, but it may make achieving constant speed a bit easier, and would make different batteries essentially have the same throttle feel. In this case the feedback is from the motor RPM back to the speed controller, much the same way a servo works. There was some discussion of this on RCU previously.

Regards
Clint

klhoard

My Feedback: (10)

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Its only illegal if you couple it with airspeed / GPS input from the plane.
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I don't think using the governor inside the Castle ESC would be useful either , you only get three (four if you count zero) selectable RPM's, which would be quite a handful to manage during a pattern sequence (but entertaining, yes!!).
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However, I believe that the usefulness comes in when you can use the governor to select RPMs from 0 to maximum with the throttle stick instead of power (stay with me here, there is a difference!!). You would have to do some data analysis of your flights and determine what RPM your batteries can give you at the end of the flight, then program the governor to limit the RPM to that at the beginning of the flight so you can achieve a consistent response thru the entire flight.
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I could even see a system where your governor would "learn" your power system over several flights and then set up its own RPM range based on a past history of voltage drops during the flight. Of course you would have to use batteries of similar age, manufacturer, C-rating, capacity for the learning to be valid. But eventually the governor could learn to limit the initial RPM to where the flights would end with enough "headroom" to keep the performance consistant thru the entire flight. Then from there you could program either a linear RPM or RPM curve that is commanded by the throttle stick.
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bjr_93tz

If the throttle response changing with voltage drop is a real problem, then 2-3 throttle curves should negate most of it.

Playing Devil's advocate, it just seems that we are allowed to spend countless hours and dollars striving to achieve mechanical perfection, but as soon as an electronic aid is mentioned it's time to burn somebody at the stake. It keeps the airframe designers/manufacturers in business selling new designs that "present" better but what about the embedded system geeks that need money too??

MTK

Electric is chock full o'nuts, huh! Don't have to worry 'bout that one with a gas "moter".

Whatever happened to "Just Fly" the danged plane. Where's RVP when you need him....

klhoard

My Feedback: (10)

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Hmmmm, yes, the throttle curves would work also. You would need to remember to keep switching them thru the flight, or use a timer to switch them. Perhaps with the new voltage feedback telemetry you could have the radio select thottle curves based on battery voltage? Maybe a good excuse to buy an 18MZ?
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One could also argue that setting 2 degrees of right thrust is a feedback mechanism and should be outlawed as well. Same for contra-props, their torque constantly "cancels" out thru the planetary gearing feedback mechanism. What about wing incidence? It is in response to the effects of gravity.
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I demand Equal Rights for electronics!!!
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Where's Al Sharpton when you need him?
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xrboss

From a pure technical perspective it would be an interesting exercise to build a feedback system from a GPS to give true constant ground speed. Observing the results and trying to fly it on a windy day would be interesting.

cmoulder

What is the groundspeed on verticals and 45's?

When one looks at today's sequences, very little time is spent flying horizontal lines.

A very wise and accomplished pilot once pointed out to me that the baseline speed for a sequence is dictated by the downline speed. If the model's drag (including prop braking, of course) cannot slow the downline speed enough to match the desired speed of the remainder of the sequence, then the remainder of the sequence must be flown faster to match the downline speed.

Which reminds me I need to fly sequences much more slowly lest the nickname "Rocket Man" become permanent.[]

Silent-AV8R

I've been playing around with a GPS module in my planes. Pretty interesting to see just how close in 175 meters really is!!!

MTK

Personally I see nothing wrong withpracticing with all kinds of goodies in the model...... should help you at least figure out the how, what and where of the model. That can directly translate at contest time.

nonstoprc

My Feedback: (90)

Well, here is my take on this argument.

There is a condition for constant motor RPM to achieve the constant ground speed: the plane is in a level flight with almost constant wind heading and speed. While the latter is ideal, we sometime can encounter during a season, dependent on where we locate. Let us not forget this context.

More importantly, that the voltage of a main battery pack will drop during the course of a sequence is a unique problem to EP. For a range of throttle positions, the gradual reducing RPMs due to dropped voltage is an extra variable to manage. If ESC can take this management job away from the pilot, it is something.

baronbrian

My Feedback: (13)

Seems to me that if engine RPM changed with fuel level, the electric guys would be calling it an inferior system...

bjr_93tz

I agree, nothing a big 42V, 100A switching regulator fed by the flight batteries couldn't sort out. A step-up type would be able to provide the maximum legal voltage from beginning of flight to end. IC guy's have been running presurised fuel systems for 25 years, this "gravity feed" of electricity from a battery needs to take a step forward..

Taurus Flyer

50

bjr_93tz

Hah, I'm a moron Now I remember my old man used to run a perry pump on his Kraft back in the early 70's. 25 years??, I must have been half asleep when I wrote that..

stuntflyr

Keith,
Most of us have used the red hand if not strong enough to ignore directly.
Chris...

Taurus Flyer

Chris,

I read you started RC Pattern in 2008 so I wonder the reason of you to write these kind of posts!

When writing about regulations it is important to know the facts, even these aren't key facts. For example to formulate a point of view.
So, pressurized fuel systems are commercial available and already used by (world wide!) well know pilots of radio controlled pattern airplanes more than 50 years ago.
Keep in mind, for about 40 years I do research for these and other systems, so I always was interested in availability of most other systems too I. RC Pattern flying started for me also more than 40 years ago!

Cees

klhoard

My Feedback: (10)

He doesn't bother me.

n233w

Hey Silent,

Tell us more about GPS (brand/make/model) and how you use it to discover your flight path. I just saw a product from "RC Logger that has lots of reference functions and "flight playback" with their software. Seems like a great learning tool.

Thanks,

Bill

klhoard

My Feedback: (10)

EagleTree sells datalogger / GPS / Altimeters that you can download your 3D flight path into Google Maps to review your flight.
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pvogel

The Jeti DC-16 radio and GPS sensor make it really easy with their PC software to view your flight, including the GPS track. Quite cool.

Peter+

klhoard

My Feedback: (10)

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I heard that in Texas they use two guys with shotguns at each turnaround pole.
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One is at 175 meters, and the other at 125 meters.
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