600 Bank Switching

[Alex Evans]

I read about this topic in several articles, showing various setups.
But, I have no idea, what is actually Bank switching.
Hope someone here explain this to me, from the start.

Thanks

 

[Admiral]

Helliman has written quite a bit on this subject, there may be other articles as well if you do a search.

FBL Gyro - Spirit Pro 'Bank Switching'

 

[Smoggie]

In a sentence:
Banks allow different setups to be stored in the FBL to allow different flight characteristics to be selected at the flick of a switch.

 

[Alex Evans]

So, if I am just a beginner and at this stage, all that I want is to learn to hover properly without crashing, Can I skip that section of the setup in Spirit pro.
It seems to me, that many of the optional functions in Spirit and other controllers are aimed at much higher needs than I currently have, many features that I will probably most likely never use.

So, can I just skip that section of setup? Maybe, one day???

Cheers

 

[Smoggie]

Yes, you can skip it if you wish though banks is useful for setting different stabilisation modes, which is useful for a beginner

 

[Alex Evans]

Ok, I have a long way to learn...
Thanks again

 

[murankar]

Its a. Ice feature when your testing multiple values.

Let's see your setting up the tail and your trying dial in the gain values. you can set three different gain values and test which one works best for you.

As smoggie stated its 3 various setups for three different flight characteristics. Generally its used either for testing values or for flight modes. I have mine setup based on three different head speeds. All the settings in one bank are geared towards a specific head speed. Depending on the aircraft the headspeed will vary.

My 570 has a 1900 2250 and 2400 head speeds.

 

[Alex Evans]

Hi Muranker,
I am a real starter here, no idea how or why should one have different head speeds?
For me, I have ahead speed controlled by my throttle, which at present is set in a diagonal straight line, 0, 25,50,75,100.
What else do I need at this point? I can't think now about any further than being able to learn to hover.

I know, for most people here, it's probably impossible to think that far back.

Cheers

 

[murankar]

Different flight styles ie: sport, mild 3d, hard 3d; all require a certain amount of head speed for one. Other scientific reasons is that higher head speed contributes to gyroscopic effect which makes the heli more stable lower gains and less fligjt time. Lower headspeed requires higher gains, in crease flight time and is less inherently stable.

There are many reason to run different headspeeds. It depends on what your doing. Its better to run static headspeed versus one that changes with collective input. A v curve is what you want; for example 80 80 75 80 80. Thats 80% throttle across the board except at mid stick which is 75%. This is how you setup a non governed headspeed.

The governor is a different topic for a different day. Today your learning about banks and headspeed. Just know that there reasons for different headspeeds. You may not be there yet but now you know.

I personally run my headspeeds in the middle of the range for a model. I find the median headspeed and set that to bank 2. I set bank 1 lower and bank 3 higher. Those 2 numbers are based on what model I am flying. I can not give you specifics because I don't care about the numbers. I care about how it feels at a given range. Every model is different. A goblin 500 flies different than a gaui x5 which flies different than a t rex 500.

 

[murankar]

Here is an example for you.

My gaui x3 on 360mm blades I have setup at

2700 rpm
3000 rpm
3300 rpm

If i run it on 325 mm blades I adjust the speeds to

2900
3200
3300 ish

Really it just depends on how it feels to you.

 

[Alex Evans]

Hello again and thanks for your time to try and explain and help me, I really appreciate it.
Coming from fixed wing flying for many years, at no point in my flying time that I setup my Classic eelectric tricycle trainer to fly in one mode, and my 63" span Mustang to fly in another. At most, the only extra function I use is Expo...

So to me, the idea of :
1) different flight mode setups
2) different head speed
3) different gain, etc...

Are all a strange language. Why do I need a different RPM at a different flight mode?
Why would I need an almost flat curve throttle setup at all pitch states?

All that I want is to hover and do small circles in front of me, with a distance of up to 30-40 m away from me.
One of my reasons to move to flying helicopters, is that with fixed wing, I am forced to flying faster and further away from where I stand, bu twith helicopter, I should be able stay slow and closer...

I know, what I just said, may sound strange and lame flying, when those machines can do so much more.

You are in it probably for several years, I started just a few months ago, with a 2nd hand Trex-600 (the one I purchased the Spirit pro fo) and a new Trex-450 that came with a Micro Beast v5, that I am waiting to maiden... I have no idea about the models you mentioned above, but appreciate your attempts to help.

It will be a great help for me if you could suggest a Spirit setup, for my requirements. I am reading the manual while waiting for the device to arrive and becoming more confused by the minute.

Cheers

 

[murankar]

Lets see how simple I can make this.

Head speed: you want a V curve to help control the head speed while under load. Again its something you will need to worry about once you move past sport flying (defined as "flying like an airplane"). Just know that a V curve is the most ideal setup for head speed. Why do I want this? It makes managing the collective much easier. The last you want is the head speed to get faster as you give collective and slower as you drop collective. It will mess with elevation and many other things as fly. Keep the speed as constant as possible.

Why banks? well because it makes it simple to change flying styles. Like I said earlier if you fly at the low end of the head speed range of a given frame you will loose natural stability. This is why we use gyros on these things in the first place. With less head speed you will need to set the gain higher to help compensate for the lack of gyroscopic stability.

Since your starting out you wont be setting up multiple banks for the purpose of flight styles. In your case you will more than likely use them to help you tune the fbl unit and that's about it. Hows this work? First get bank 1 setup to fly somewhat well for you. Then you can go into banks 2 and 3 to fiddle around with numbers. Lets take the tail for instance; you get it solid in bank one. On bank2 add about 10 points of gain and then on bank 3 add another 10 points on top of that, (ie: set bank one at like 65 as a starting point, bank to at 75 bank 3 at 85) go fly it and switch through the banks and watch how the tail responds to the gain changes. You can do the same thing with any of the settings in the FBL unit. It makes tinkering easier without messing up your base model. You can do this with the head gain, motor speed, really anything. Head speed for instance lets use my example from earlier. Gaui X3 on 360mm blades; Lets say you find 3000 rmp a nice comfortable speed to fly. The response is nice, the gains are easy to set and gives you an decent amount of flight time. One day you ask yourself: Self what would 3300 rpm feel like on this kit? Instead of asking us just set a bank with the new head speed by adjusting the throttle curve higher. When you get to the field all you have to do to try the new setting is flip the switch and watch what happens. Either you wont like it or you will. Either way you can do that and see if you do like it.

I did the same thing you are doing. I bought an item then watched videos about it and read the documents. It may not click until you actually start to muck around with it.


What I would do is setup the 450 you got on the spirit fbl. Then I would setup the model for 3000 rpm. You can do the math to find that out. based on your answer then you can set your throttle output accordingly. Once that's done then go have fun and fugetaboutit. MrMel headspeed calculator v3 there is the link to Mr Mel's head speed calc. Motor peak efficiency is going to be your throttle output. At least that's how I do it. So if I set the throttle to 75 then I use 75 as the peak to get a close guess to the head speed.

 

[Alex Evans]

Thanks again,

My 450 is fully set already with the Microbeast, just waiting to fly it.
The Spirit Pro is intended for my Trex-600, was supposed to arrive yesterday, but didn't...

I am not likely to fiddle with anything, but time will tell

Cheers

 

[murankar]

I suggested the 450 for the simple fact that its cheaper. If you start to play around with settings and put it in then the repair will be cheaper that's all.

 

[Alex Evans]

OK, I understand you thinking about money, to me this is not the case.

I DO NOT LIKE TO FIDDLE. Once I set up a plane / heli -it will stay like this forever, or until I crash it.
The 450 took me a month to get it configured with the Beast, no way I am going to start all over again with another controller. The Beast was not easy to say the least, I am not inclined to go through it again from the start with the 600.

Yes, I noticed that parts for the 450 are cheaper, but I don't care about it. I got the 450 only becasue a friend suggested it as a better starting model, in my mind - the 600 size is likely to be better for me because:

1) If it drifts away, I have a better chance to see it and less chance to get dissoriented, and
2) It is likely to be more stable, being heavier

Thanks again

 

[Smoggie]

Alex, picking up on the throttle curve discussion:

The general idea on a collective pitch heli is that rotor RPM should remain constant. To climb and descend uses change in blade pitch, not change in RPM.

For this reason your throttle curve should be ‘flat’ or ‘nearly flat’ . Don’t use a throttle curve of the type used on a plane as that will mean rpm will change when you move the collective stick, which is not what you want.

best way to keep constant RPM is with governor, but if not using governor then a curve with a slight ‘V’ shape works well too

 

[murankar]

If money is not an issue then yeah the 600 is a better learning tool over a 450. It will fly way better because of its size.

 

[Alex Evans]

Alex, picking up on the throttle curve discussion:

The general idea on a collective pitch heli is that rotor RPM should remain constant. To climb and descend uses change in blade pitch, not change in RPM.

For this reason your throttle curve should be ‘flat’ or ‘nearly flat’ . Don’t use a throttle curve of the type used on a plane as that will mean rpm will change when you move the collective stick, which is not what you want.

best way to keep constant RPM is with governor, but if not using governor then a curve with a slight ‘V’ shape works well too

Smoggie,

It's the first time anyone explains to me the reason for this "Strange" throttle curve, many thanks. Now I can relate to it through my young years in the Airforce working on French Allouette II (later Lamma), throttle RPM was fixed throught the flight from the start.

For a Trex-600 FBL / DFC - what curve setup will you syggest? I have no idea about Governer, can I set it without?
Please consider for your answer that at this stage, all that I want to do in Normal mode is learn to hover and a bit of turning in circles in front of me. My pitch setup is : -3, 0 at mid throttle, +8 at the top.

What is this magic 6 degrees I read about?

Thanks again

 

[Smoggie]

If you want to have the motor stop when you pull the collective stick back (no use for inverted but ok for your desired flying style) try this curve:

0-65-70-75-80

nothing magic about 6 degrees that I’m aware of?

 

[Alex Evans]

If you want to have the motor stop when you pull the collective stick back (no use for inverted but ok for your desired flying style) try this curve:

0-65-70-75-80

nothing magic about 6 degrees that I’m aware of?

Much appreciated,

I have my ESC startup to soft, so jumping from - zero to 65 is OK?

Cheers