jroo

I'm lost on the meaning of the D\R and EXPO settings on the DX6i.

In the DX6i manual this definition is given:

The Dual Rate and Exponential function allows two control rates to be programmed and selected with a switch.
Dual rates and Expos are available on the aileron, elevator and rudder channels. Changing the dual rate value not
only affects the maximum control authority but also affects the overall sensitivity of control. A higher rate yields a
higher overall sensitivity. The sensitivity around center can be tailored using the Exponential function to precisely
adjust control feel.

Huh? What the **&%# does that mean? I'm new at helicopters and that makes 0 sense to me. How does a EXPO of 15 differ from 30 for example?

I watched the 'DX6i Setup for Beginner Pilots' on the Horizon Hobby website, and that guy presenting the video:

A) Thinks he is way to way too cool, with this 1/2 cocked eyebrows
B) Cannot give a explanatory presentation to save his life
C) Provides absolutely ZERO insight as to what the settings do. "You will want this at +30." uh ok WHY?

The older gentleman (who provides a great array of other rc video presentations) tries to coax explanations out of the this guy, but gets nowhere. He seems to be as frustrated with him as I am.

So could someone, please, in layman's terms, please explain these values?

I've also read that there is some discrepancy of whether a new pilot should even use these beginners settings, as some say it will wreak havoc on the servos... Is this true?

evdreamer

Dual rates have two settings that you can choose. When you use those it limits the full travel of the servos to where ever you want. It is mainly used on airplanes when people want to fly nice and easy they will limit the servos so the airplane won't do moves very fast. Then when they want to do aerobatic moves they will hit the Dual Rate switch and now they have a new set of servo limits that usually go to their full travel, so the airplane will do rolls very fast. The same can apply to helis in that you can have two different roll rates. This uses a linear curve.

EXPO is short for an exponential curve. With this setting, the servos aren't limited on how far they can go like Dual Rates does. However, it limits how much the servo moves per how far the sticks move. It is mainly used for new fliers when they are learning not to use big stick movements to correct the heli. Usually the servo won't move very much around center stick with positive EXPO, but once you max the sticks out you have full servo travel. I think it is negative EXPO on the DX6i that it does the exact opposite and makes center stick very senstive, so the heli will move a lot with very little stick movement around center and moves less with a lot of stick travel.

When you go from 15% EXPO to 30% EXPO the heli will respond less to stick movements around center stick. If you add some EXPO and watch the EXPO curve and see what the servos are doing when you go from center stick to the stick limits it might help.

It won't damage your servos if you use either of these settings. Hopefully this sheds some light on what these mean.

Nick

dknovick

I'm not sure what you read about wreaking havoc on servos, but if the settings and servos are properly setup (i.e. you don't run the servos to their limits), everything should be fine


Dual rate allows you to have 2 different servo movements corresponding to stick movements (with the flick of a switch). So for example, you could have a 50% setup on your dual rate switch. With the switch in one position, if you move a stick to it's extreme, the servo moves to it's extreme. If you flip the switch (to 50%), if you move the stick to it's extreme, the servo only moves 1/2 as far.

Exponential (Expo) allows you to this without having to flick a switch. Depending on what your controlling, you can set up a slight servo movement "around the center" of the stick, but still go to the extremes of the servo when you move the stick to it's extreme.


This may help:
[link=http://www.rmfm.org/dual_rates_and_exponential1.htm]Dual and Expo rates[/link]

-Dave