SpartanRC DS760 Gyro Review and Setup Vids

[Finless]

Hmmmm good question. I haven't tried this myself but as Angelos says most radios these days sub trim "slides" within the ATV's and thus as long as your ATV's are not maxed out you wont notice more throw in the trimmed direction.

Bottom line you can test this yourself with a servo alone. Set ATV's to 100/100 and then move the stick full left or right and measure the servos end throws. now TRIM or sub trim in either direction. Now move the stick full left and right again and you will see the same amount of throw. e.g. the trimming had no effect on the max deflection.
Now if you ATV's are maxed out (radio dependent) then you will see a difference.

Bob

[xStatiCa]

Thanks for the info. That clears that up that I have been going over in my mind but never tested for over a year now :).

I am the type that has to understand how things work at the lowest level I can so I apologize if I am going too deep in the questions but I have another if you are up for the challenge of trying to understand my ramblings :).

So when you set the limits on the gyro what servo output do you(as the gyro embedded programmer) use for the center point for the limit adjustment? In other words if you adjust the left and right limit all the way in on both left and right what would the center of those two servo signal outputs be? Arent all servos slightly different? Not that it really matters because you have separate limits for both sides and I am sure you have plenty of adjustment available to not be a problem if it is off from the real servo arm at 90 degrees.

I can see where having separate left and right limit adjustments might come in handy now. With a single limit adjustment if your servo when at 90 degrees on the arm is at a different position than what the center position of the limit adjustment is based off of then you will have less limit on one side than the other from your servo 90 degree angle center point.

Example for above with only one limit adjustment(gy401, G770 3D, etc):
limit adjustment center = x
limit adjustment end points based on center x above = y
Servo at 90 degrees at hover = o
|y---xo--y---|

Notice that the above example causes you to loose some movement to the right because the servo at 90 and the gyro limit signal center does not match.

Ideally I would have wanted it to be equal from the servo 90 degree center point:
|z---xo----z-|

The issues above is why I wondered if the gyro took the tx signal at power on to base the limit adjustment on.

Now how much this really is off might be so slight that it doesn't really matter normally for the gy401, G770 3D, etc. If you can not get the servo horn at a 90 degree angle without any trim/subtrim in rate mode though it could be off by quite a bit I would think(that is a different subject though). If it is off by a lot then having the separate limit adjustments would come in handy.

Any of this make sense?

[highland flyer]

I know this may seem a a dumb reply on what only amounts to a theory based answer.

In the radio you do not want any subtrim as the Gyro uses this as it's (stationary neutral point) otherwise it will creep.

Tail travel limit does vary in each direction as it is dependant on the particuliar models tail geometry and physicial tail slider travel limits, servo horn length/position.

Hover neutral position(The flight neutral point) can only be truly determined by flying in rate mode.

The tail travel limit is just that the physical amount of travel on the tail slider. The Gyro uses this to limit the slider travel in flight to prevent binding only. NOTE:-. It has NO effect on piro rate.
The tail travel limit % we actually see in the Gyro software is often an un-even figure each direction due to tail geometry of the model.

The Rudd ATV controls the piro speed only each direction

The idea of trimming the Gyro in rate mode is to find the approx hover pitch required to counter the main rotor torques. As far as I understand this, the gyro uses this as a reference point only, but the closer we can "Guess" this the less additionial calculations a Gyro has to do in flight. note:- the word Guess.

For example on the CSM720 this makes a huge difference to how well it can potentially perform and requires you to pre-set your talblade pitch in rate mode for best results. The CSM also has additional software programming to help teach the Gyro the tail blade position in flight (the flight neutral point). Even with this added programability it is still a compromise as the model will be moving, up/down/forwards /backwards/wind/ is headspeed dependant etc.

This setting is completely unique to each and every helicopter, as we use different, servo's, radio's, control rod settings, servo horn lengths and other things such headspeed, paddles/blade brand/length/ flybar length, tail blades size, gear ratio, air density, assymetric tail travel to help balance piro speed travel each direction. (with/against torque)

As Finless pointed out many of the 'Pro's' just stick it mid slider. Whist this works well for most Gyro's try this with a CSM and your results will be far from ideal.

The rest is in the Gyro designers head!

Sorry for the not so quick reply!

[xStatiCa]

I think an entire book could be written on 'R/C Helicopter Tail Control with Conventional gyros - Theory and Practical Use for the anally retentive builder' :Deal

Anyone want to help get a Creative Commons license book with that title going? :).

[IcemanCharlie]

I just got my 760 and I tried it a little in my T-600 N.

I have used a 410 gyro before together with a S9254 Servo.

Now when I check my Low&High endpoints I can see that it's "rather" high, 128 and 143.

So if I understand this correct this is to high ( 90-110 in the manual) so I have to move the ball 1 or 2 steps further away on the servo arm.

This IS really a nice thing to see in the software!!

IF I would leave it as it is, would it be over sensitive or ?

[highland flyer]

Iceman. The 600N is a little unusual in that it has an extremely powerfull tail (known as high mechanicial gain) and every Gyro brand fitted to it thus far has required a little shorter servo horn than most folk are used to running. To keep a reasonable gain level a servo horn of around 12-13mm gives good results and as you have found the endpoints are a little higher than normal.

Also the 600N is a little flexi at the back end and the Align boom clamps are very prone to moving. I highly recommend the Quick UK item to eliminate any movement here.

You could adjust your tail rod length to balance out the %'s a little if you wish.

Due to the slight flex in the rear frame area you may wish to soften the stops some.. if your getting any bounce.
My own preference is to move the ACC/DEC sliders towards the slow position, approx the 25% position and increase the stop gains to 120 each. If I remember correctly my Hi/lo endpoints are just on the 128/132 or there abouts and I also removed the Gyro Expo to suit my taste with about 10% in the Tx instead.

hope this is of use to you cheers..Brian

[highland flyer]

Hi Guys I stuck a couple of photo's over on rcheliaddicts of the new Software If your interested

http://www.rcheliaddict.co.uk/showthread.php?p=92894#post92894

[IcemanCharlie]

Iceman. The 600N is a little unusual in that it has an extremely powerfull tail (known as high mechanicial gain) and every Gyro brand fitted to it thus far has required a little shorter servo horn than most folk are used to running. To keep a reasonable gain level a servo horn of around 12-13mm gives good results and as you have found the endpoints are a little higher than normal.

Also the 600N is a little flexi at the back end and the Align boom clamps are very prone to moving. I highly recommend the Quick UK item to eliminate any movement here.

You could adjust your tail rod length to balance out the %'s a little if you wish.

Due to the slight flex in the rear frame area you may wish to soften the stops some.. if your getting any bounce.
My own preference is to move the ACC/DEC sliders towards the slow position, approx the 25% position and increase the stop gains to 120 each. If I remember correctly my Hi/lo endpoints are just on the 128/132 or there abouts and I also removed the Gyro Expo to suit my taste with about 10% in the Tx instead.

hope this is of use to you cheers..Brian

Thank's man :-)

Sorry but the "Quick UK item",what's that ?

Soo, I can just leave the ball and as you said just trim the length on the rod.

Once moore, THANK'S !

[highland flyer]

Ice, I meant the Quick UK boom clamp

cheers

[IcemanCharlie]

3D Lightweight Tail Clamp - TXT-12
http://www.quickuk.co.uk/acatalog/r_index.htm

Is that the one or..

[highland flyer]

Yes thats the one. I tried the Align metal one but it was no better than the plastic version. The plate that clamps the boom is the same in both versions and distorts.

You can do a qiuck fix by replacing the horozontal fin with a thick piece of scrap carbon 2.5mm/3mm but you will see the clamp only really compresses the boom at the top and will start to mark, even dent the boom a little at the top, but it will work for a while at least.

The Quick UK item clamps the boom 360 degrees so spreads the load evenly

[Finless]

FYI I plan to do a video with overview of this software but I managed to catch a really bad cold and my voice is almost gone :(

Stay tuned I will have something as soon as I feel better.

Bob

[MarkWebber]

Sounds like you need someone to a "voice-over" for ya;)

[Pinecone]

Actually thinking about it, ifyou want 90 at center travel, center the servo. Get the horn that is closest to 90, install, manually move the servo (or use a servo tester) to get the servo arm 90 and then adjust the tail slider to center.

Then hook up to the gyro and set the limits. Since the tail will drive to where it needs to be, it doesn't matter if center stick is center slider in rate mode. But the linkage will be setup to give equal throws from center slider position.

And BTW most AR Spektrum Rxes do NOT fail safe to the bound position. They fail safe to neutral on all except the throttle that fail safes to bound.

The binding sets the INITIALIZATION positions. When the Rx powers up, but before it gets a valid Tx signal, it outputs the bound positions to all except the throttle, which gets no signal.

The BR6000 does failsafe to obund positions. And the AR9000 allows you choose to failsafe to neutral or to bound position.

[jurassic5]

Hi everyone,

After reading this thread and viewing bob's videos.. and angeloz kind replies... I just bought this DS760 for my TREX 500.

Cédric

[Mercuriell]

I've had 10 flights now on my Logo 5003D with Spartan gyro and tail is ROCK solid with 9254 and R&B 89mm blades

[CompuFoil]

Waaa! Get the DS650 in production pleeeeeze!

[th3tick]

I've had 10 flights now on my Logo 5003D with Spartan gyro and tail is ROCK solid with 9254 and R&B 89mm blades

So is it the Rhythm or the Blues that makes those blades so solid? ;)

[Mercuriell]

So is it the Rhythm or the Blues that makes those blades so solid? ;)
:o

[jurassic5]

I just received my spartan ds760 with the usb cable. Waiting for the TREX500.

All I can say is that the packaging and gyro is HIGH QUALITY. Even the little package is made of nice foam. Like a jewel.

Really nice job on this guys.

Cédric

[TheBum]

Waaa! Get the DS650 in production pleeeeeze!

+1. I'm OK as long as it starts shipping before March.

[BruceW]

Are there plans to add a dynamic reading of the gyro gain into the configuration software? It would be nice to read it as the gyro sees it from the rx since the question of what radio was used to set the gain (and if your in gear or gyro sens mode) always comes up.

[MarkWebber]

For those of you that don't want to connect to your gyro with the USB cable, here's a sneak peak at what Spartan's up to. Hope Angelos doesn't mind me sharing. They're still working on it but watch for it in the next few months. Angelos will let us know when he's done with it.

[th3tick]

Ooh, that makes me WinCE! I just hope you can make my Palms sweaty too ;)

John

[mporlier]

I have a question,

I went flying today and I found that when I was turning downwind the tail was wagging like crazy. It was around 15mph.

Sideways and upwind was very stable. When I was turning the tail wagged a lot until I picked up speed. I guess the tail wind, when flying fast, had less effect.

Is this a sing my gain was to high?