下文转载Futaba官方FAQ信息，有兴趣的朋友可以看看。
Radio System FAQ
Please explain dual rates/DR/AFR, exponential, and ATV/EPA and how they are related.
1. What is EPA (end point adjustment)? How does it differ from ATV (Adjustable Travel Volume)?
EPA is each individual servo's end point adjustment. ATV is the older term for EPA, but has been used to mean a variety of levels of adjustability. EPA specifically has one adjustment for each end of each servo. EPA is specific to each individual servo, so adjusting the EPA to the aileron channel will not, for example, adjust the servo throw of the second aileron servo if you have flaperons set up. EPA is the 'master' control. That is to say, it takes priority over all other items. Therefore, adjusting EPA will affect anything else that is a percentage from that number, including rates, exponentials, and mixes.
2. What are "high/low rates", dual rates? How does this differ from AFR and DR in the 9Z?
High and low rates are used to give the aircraft two different 'feels' in flight. For example, low rate aileron might be set so that your plane does one complete roll in one second when giving full aileron stick. That's perfect for that roll, but not enough to make corrections in case of wind gusts or doing stunts in the rest of your flight! The first half of the dual rates on the 9C is the same as AFR on the 9Z. This is what the 9C, 8U and 6X consider the first switch position in dual rate which most modelers use as their high rate. AFR is active until the dual rate is activated, and it belongs to each CONTROL or AXIS of the airplane. Therefore, adjusting high rate (or AFR) for ailerons in a model with flaperons will affect the throw of both servos. Why set a high rate instead of adjusting EPA/ATV? Easy. EPA is your end point for EVERYTHING the radio does....mixes, expos, everything. So if you have a low rate, mixes, etc, that you like, but you need a little more (or less) on high rate, adjusting EPA will mess up all that other work. Just adjust the high rate itself and this doesn't affect anything else.
3. What is Exponential and how do I set it?
Exponential is an adjustment to the actual curve of how the inputs are given to the servo in relation to how the stick is moved. Without expo, the servo gets exactly the same amount of movement command per millimeter of movement of the gimbal regardless of the gimbal's position (center, or extremes, for example). Many modelers use expo to soften the feel of the model's response around center to avoid over correcting. It is also recommended to add additional negative expo to high rates so that the high and low rates give similar distance of travel around center. This is helpful to avoid overcontrolling in panic situations or when changing rates.
Exponential is set independently for your 'high rate' and 'low rate' (called dual rate), by flipping the switch, just as you did setting the two dual rates |
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发表于 2005-3-17 23:10
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