Throttle and Pitch Curves: Tech that makes flying fun
This page is all about throttle and pitch curves, how they work, what they do, and why you've gotta love them.
Introduction:
In order to fly, all helicopters have to be able to adjust their throttle. Aside from micro helis, any helicopter has to be able to adjust its throttle AND collective to fly well. On RC helicopters, this is accomplished by throttle and pitch curves. Whether you have a computerized radio or not, in order to fly your radio has to have programmed throttle and pitch curves. This could be as simple as a linear curve or more advanced, such as a V curve.
How do you control both throttle and collective? This at first might seem confusing, because both throttle and collective are controlled via the same stick movement: up and down on the left stick. For simplicity, I will refer to the up and down movement of the left stick as the throttle stick.
The answer is fairly simple, however: programming. With today's technology, it's easy to program the controller (whether or not its computerized) to mix the output of throttle and collective with any input of the throttle stick. With a computerized radio, the person who programs the throttle / pitch mixing is not the factory, but the user. Don't worry, this page is not an argument for computerized radios.
How do you control both throttle and collective? This at first might seem confusing, because both throttle and collective are controlled via the same stick movement: up and down on the left stick. For simplicity, I will refer to the up and down movement of the left stick as the throttle stick.
The answer is fairly simple, however: programming. With today's technology, it's easy to program the controller (whether or not its computerized) to mix the output of throttle and collective with any input of the throttle stick. With a computerized radio, the person who programs the throttle / pitch mixing is not the factory, but the user. Don't worry, this page is not an argument for computerized radios.
How They Work:
How do throttle and pitch curves work? Whether factory set or user programmed, they take the shape of a series of linear curves. Depending on your radio quality and frequently the number of channels, your control over the number of line segments could vary from none with a non-computerized radio to up to 11 or so on top brand products.
Why would you want more line segments?
First off, its important to recognize that the slope of each line segment is how fast the throttle or pitch (for a throttle or pitch curve respectively) changes over that interval. A higher slope means a greater change.
Well, back to the question at hand, the more line segments the smoother the change of each slope from segment to segment. You generally don't want any big changes in slope because otherwise, while in the process of controlling your helicopter, you will have sudden changes in the responsiveness of your throttle stick depending on its position. This makes control more unpredictable.
As a beginner in particular, more line segments means that you can smooth out the pitch over a larger range of your throttle stick. This makes it easier to master collective control. More line segments are also desireable to allow smoother flight, especially for scale helicopter applications.
Basically, each curve ties the amount of that curve (pitch or throttle) to the position of the throttle stick. The two curves are independent: you could have your throttle curve at only 100% and your pitch curve from 0-100%. Most entry level computerized radios have five control points, or points where a line segment stops and / or begins. This allows 4 line segments, or 4 varying degrees of slope.
Each curve is programmed separately and independently, yet they are both tied to the movement of the throttle stick. Thus, whenever you move the throttle stick, both collective and throttle will change (unless you have set the slope of one or both curves to zero over the interval).
I would recommend, if you are buying a computerized radio, to just go for a good 6 or 7 channel one. That way you have more money available to buy a quality helicopter. After all, a top of the line radio won't do any good with a poor quality heli. If you have the resources and lots of RC helis / planes (or cars?) and already have a 6 or 7 channel radio, go ahead and get a higher quality radio if you want. I would do this if you want to fly scale helicopters (that is, rc choppers that look like real, full size ones) with all the cool things like lights, landing gear, moveable rescue equipment, etc. I would very rarely, unless you have or are about to get scale rc helis with these extras, recommend getting more than a 7 channel radio as your first computerized radio.
Why would you want more line segments?
First off, its important to recognize that the slope of each line segment is how fast the throttle or pitch (for a throttle or pitch curve respectively) changes over that interval. A higher slope means a greater change.
Well, back to the question at hand, the more line segments the smoother the change of each slope from segment to segment. You generally don't want any big changes in slope because otherwise, while in the process of controlling your helicopter, you will have sudden changes in the responsiveness of your throttle stick depending on its position. This makes control more unpredictable.
As a beginner in particular, more line segments means that you can smooth out the pitch over a larger range of your throttle stick. This makes it easier to master collective control. More line segments are also desireable to allow smoother flight, especially for scale helicopter applications.
Basically, each curve ties the amount of that curve (pitch or throttle) to the position of the throttle stick. The two curves are independent: you could have your throttle curve at only 100% and your pitch curve from 0-100%. Most entry level computerized radios have five control points, or points where a line segment stops and / or begins. This allows 4 line segments, or 4 varying degrees of slope.
Each curve is programmed separately and independently, yet they are both tied to the movement of the throttle stick. Thus, whenever you move the throttle stick, both collective and throttle will change (unless you have set the slope of one or both curves to zero over the interval).
I would recommend, if you are buying a computerized radio, to just go for a good 6 or 7 channel one. That way you have more money available to buy a quality helicopter. After all, a top of the line radio won't do any good with a poor quality heli. If you have the resources and lots of RC helis / planes (or cars?) and already have a 6 or 7 channel radio, go ahead and get a higher quality radio if you want. I would do this if you want to fly scale helicopters (that is, rc choppers that look like real, full size ones) with all the cool things like lights, landing gear, moveable rescue equipment, etc. I would very rarely, unless you have or are about to get scale rc helis with these extras, recommend getting more than a 7 channel radio as your first computerized radio.
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