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Old Sep 13, 2010, 03:21 PM
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Quote:
Originally Posted by Reflex1 View Post
Quote "throttle (collective) needing to be run from a separate channel and not running through the gyros.Quote

No need to apologize

The Collective IS feed through the Gyro's
eCCPM ensures all 3 esc's get the same signal for throttle.

Cyclic is controlled by Differential Signals to the esc's

The Tx Swash mix controls the Ratios of mixing

The Rx feeds the Gyro's with a Control Signal (Chns) which overrides the Gyro Correction the Gyro's pass this to the esc's
Hence you have Collective control.

I'll post Full setting from my FF9 tomorrow
No extra "Trick" mixes are involved only eCCPM

I also will try to post proof, to show the Gyro's are in HH at ALL times
to dispel any doubters.

Paul

Cool
I understand about the CCPM mixing giving the throttle signal for all 3 ESC but that only applies for rates mode. HH dont work like that. I believe that you have your gyros in HH mode but now to find the reason they responding the way you say. I think what cyhyam says may be very plausible or something similar. It was one of the reasons I asked where you set your limits on your gyros.
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Old Sep 13, 2010, 05:21 PM
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Highland, CA, USA
Joined Jan 2001
1,103 Posts
Quote:
Originally Posted by Reflex1 View Post

Swash AFR
Ail +40
Ele +40
Pitch +60

Pitch Curve is very interesting and may be a major clue
1. 0%
2. 14%
3. 26%
4. 40%
5. 50%
Quote:
Originally Posted by Reflex1 View Post
Sorry thats not it

The First thing I did was Calibrate these 3 esc's to my Tx
In Aircraft mode endpoints set at 100%
I did this so the esc's "Tracked" together,Very important for eCCPM
The fact that your swash AFR on pitch is +60, about 20% lower than most and your pitch curve is 0 – 50%, indicates
that the ESC’s are not using 0 – 100% as the full throttle range. This would keep the neutral range during throttle / pitch
changes from exceeding 1.575ms and shutting down the HH gyros.

With most tri setups when the ESC’s are programmed with 0% as off and 100% as full throttle the collective curve would be
0 – 80% allowing the 20% overhead for cyclic corrections.

Since your ESC’s see 50% as max throttle minus the overhead, they must see 70% as full throttle. That doesn’t work out
if they were programmed with the full range “airplane mode”

They most likely have been programmed or they wouldn’t track together, but they are seeing / using a limited range.

Next time you have a heli powered up move the TR stick 15% off center and wiggle the boom, the gyro does not try to
correct….in either direction. Once you bring the stick back, close to center the gyro starts correcting.

What I said before is still true. Your setup does not have the collective changes large enough to offset the neutral of the
channels to the point where the gyros quits.
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Old Sep 13, 2010, 06:24 PM
X-Ikarus
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United Kingdom, North York
Joined Feb 2003
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Quote:
Originally Posted by cyhyam View Post
The fact that your swash AFR on pitch is +60, about 20% lower than most and your pitch curve is 0 – 50%, indicates
that the ESC’s are not using 0 – 100% as the full throttle range. This would keep the neutral range during throttle / pitch
changes from exceeding 1.575ms and shutting down the HH gyros.

With most tri setups when the ESC’s are programmed with 0% as off and 100% as full throttle the collective curve would be
0 – 80% allowing the 20% overhead for cyclic corrections.

Since your ESC’s see 50% as max throttle minus the overhead, they must see 70% as full throttle. That doesn’t work out
if they were programmed with the full range “airplane mode”

They most likely have been programmed or they wouldn’t track together, but they are seeing / using a limited range.

Next time you have a heli powered up move the TR stick 15% off center and wiggle the boom, the gyro does not try to
correct….in either direction. Once you bring the stick back, close to center the gyro starts correcting.

What I said before is still true. Your setup does not have the collective changes large enough to offset the neutral of the
channels to the point where the gyros quits.
I see your logic however you have forgotten about Gyro Travel adjustment
On mine the Cyclic Gyros are set to Full Travel.
I could connect a servo and check its travel from the Gyro output BUT

I have to report tonight's attempt to fly the Tri. was a disaster
Indoors at our Dome Sports hall the Tri was almost unflyable.

No settings have been changed, but it was suffering from severe Cyclic
interaction.

The cause ? Vibration after the repairs I had not been as thorough
eliminating vibs. (lack of time)
I could feel a distinct low freq. vibration on the Gyro cases

Now "Mixing" signals was mentioned earlier
This also applies to Vibration

Consider 3 motors & props all running at varying speeds
connected to 3 Vibration sensitive Gyro's controlling the motors.
All in 3 different "Planes"

Freq. generated are Original , Sum and Difference
Also Vibes in One motor can affect the Gyro controlling another Arm motor

The Potential for Cyclic interaction are Huge

I'm satisfied that is the reason for peoples failed attempts to use HH

Gyros in HH mode Store these Vibe signals in memory
making a bad situation even worse.

I have a lot of work to do to bring my Tri's vibration levels
down to yesterdays levels

Still its been an interesting discussion, Thanks guys!

Paul
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Old Sep 13, 2010, 06:43 PM
SSM
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Australia, VIC, Canterbury
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Quote:
Originally Posted by Reflex1 View Post
I have to report tonight's attempt to fly the Tri. was a disaster Indoors at our Dome Sports hall the Tri was almost unflyable.

No settings have been changed, but it was suffering from severe Cyclic
interaction.
Suddenly I feel that we're back to square one (in rate mode) and that we've lost our Nirvana, the 5th dimension, Utopia, heaven.

Still, it's been a great discussion, if somewhat academic!

Simon (aka SSM, which means "Silicon Micro Machine" or something)
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Old Sep 13, 2010, 06:53 PM
X-Ikarus
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United Kingdom, North York
Joined Feb 2003
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Simon. I think its been productive
at least you know its possible to use HH

I won't switch to Rate Mode
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Old Sep 13, 2010, 07:54 PM
Frogman
Stoughton, WI
Joined Jun 2009
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Quote:
Originally Posted by dragant View Post
hahaha
It's a popular photo session place for wedding couples.
I shoot wedding videos for a living here in the states....wooohooo that shows I can use a tri for shooting wedding footage. Now I have an excuse to pack it on a wedding day. Like my wife will go for that.
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Old Sep 13, 2010, 08:25 PM
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Nevada, USA
Joined Sep 2007
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Quote:
Originally Posted by Reflex1 View Post
Simon. I think its been productive
at least you know its possible to use HH

I won't switch to Rate Mode
Whats the avantage you see using HH vs rate mode which has been proven to be rock solid and reliable? By the way I have enjoyed this discussion and have learned a lot more about HH gyro's than I ever knew!
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Old Sep 13, 2010, 10:46 PM
Balsa + glue + bluesky= fun
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Phoenix AZ USA
Joined Jan 2009
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The tri is getting steadier by the day. I shot some key cam video today. Taped it on the center plywood. I expected some jello and did get a little but not too much. After seeing Tim's jello free vids it got me thinking. Could putting the gyros on that type of foam Tim puts his camcorder on help? Thoughts?
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Old Sep 14, 2010, 12:53 AM
UAV Dude KF7HYV
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United States, NV, Silver Springs
Joined Mar 2007
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Quote:
Originally Posted by leaktech View Post
The tri is getting steadier by the day. I shot some key cam video today. Taped it on the center plywood. I expected some jello and did get a little but not too much. After seeing Tim's jello free vids it got me thinking. Could putting the gyros on that type of foam Tim puts his camcorder on help? Thoughts?
it would be easier and cheaper to remove the vibrations than try to dampen them. Your flight performance will increase, also.
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Old Sep 14, 2010, 02:26 AM
X-Ikarus
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United Kingdom, North York
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Quote:
Originally Posted by capt View Post
Whats the avantage you see using HH vs rate mode which has been proven to be rock solid and reliable? By the way I have enjoyed this discussion and have learned a lot more about HH gyro's than I ever knew!
It seems I'm the only one able to answer that question having flown both modes on a Tri.

Simple answer is Great Stability throughout the full flight envelope.

Keith's (Kf52t) Tri. is extremely well set-up and flys very well in Rate mode
However I could "feel" it's stability dropping drastically as I increased Forward speed, I felt it unsafe to apply Full Throttle
I have noticed other comments here indicating the same "feeling"
As though it's a big challenge to go Full throttle in forward flight.

My Tri in HH was a different experience, in flight I could use the Full throttle range and it was Fast, Stable and predictable at all times as shown in the Video.

It was also easy to hover and stayed where I put it in the gusty conditions.
This is exactly what I expected from HH and has proved true in practice.

When its sorted and I see Keith next at the field
I'm looking forward to hear his impressions when he fly's mine in HH .

Paul
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Old Sep 14, 2010, 04:05 AM
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Ilford,Essex, UK
Joined May 2006
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Quote:
Originally Posted by opus View Post
I thought it was Rev. Richie. Instead of looking it up I kept it general. The schedule 40 PVC is pretty strong. It is a little heavier, not terribly though. The whole air frame with body and struts weighs I think 430g. I was looking to do something a little neater than having the cables/components hanging all over it. Nothing against anyone else's design, I'm just a little OCD. (CDO if arranged alphabetically)

From my model picture, you can also see I've mounted the motors on the bottom side of the struts. I read a month or so back @GALENM mounted his motors upside down from everyone else's setup. I like the mechanics involved here. It also makes for a sleeker design. I have the struts mounted to the body and all painted up. It looks really great. I just haven't had the $$ to get any electronics.

I like your idea of air vents on top and bottom. If I put the top vents below the prop wash and bottom vents past the ESC, I could probably get some flow-through. I'll have to test. Thanks for the idea.
I think putting hole top and bottom would posibly defeat the object a little, if the holes are on top with the air blowing into them the air will " turn" and travel along the tube to its inboard end ( blow this over the lipo as further benfit) and may keep the esc cool.


BTW you cant see the wires on my "woody" a simple rebate in the bottom of the arm allows them to be tucked in but i think the tube idea is great.
When you say schedule 40 is this used for plumbing / electric so I can find it in my hardware store.

What method did you use to get such a neat oval when you heated the tubes?

I may look at this as a build method for my next tri (T copter)

Regards Jeff
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Last edited by Upup; Sep 14, 2010 at 04:27 AM.
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Old Sep 14, 2010, 04:44 AM
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Joined Nov 2007
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Quote:
Next time you have a heli powered up move the TR stick 15% off center and wiggle the boom, the gyro does not try to
correct….in either direction. Once you bring the stick back, close to center the gyro starts correcting.
Hi cyhyam

I dont understand this, is this rates or HH?

In Rates you would see the servo correcting similar as if TR stick neutral while wiggling the boom.

In HH your servo would have moved over to its limit and not be moving because it has hit its limit trying to get the gyro to rotate but if you were spinning with the heli at the gyros requested rate then wiggling the boom it would react the same as in HH. This is the reason why if you pirouette a helicopter stationary in very strong wind it still rotates a constant rotational speed where as a pirouetting helicopter in rates mode would speed up and slow down in the rotation as the tail goes with and against the wind
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Old Sep 14, 2010, 07:19 AM
X-Ikarus
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United Kingdom, North York
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Quote:
Originally Posted by talkthetorque View Post
Hi cyhyam

I dont understand this, is this rates or HH?

In Rates you would see the servo correcting similar as if TR stick neutral while wiggling the boom.

In HH your servo would have moved over to its limit and not be moving because it has hit its limit trying to get the gyro to rotate but if you were spinning with the heli at the gyros requested rate then wiggling the boom it would react the same as in HH. This is the reason why if you pirouette a helicopter stationary in very strong wind it still rotates a constant rotational speed where as a pirouetting helicopter in rates mode would speed up and slow down in the rotation as the tail goes with and against the wind
I'm sorry, but both cynyam and talkthetorque's explanations are incorrect

The Gyro Only senses rotation which it corrects for without pilot input.

When you apply pilot input the speed of rotation is dictated by the amount of stick deflection , the Gyro works to control this.

This is the same in Rate and HH mode. Wind will have no effect on rotation speed (within limits of course,hurricanes excepted) the Gyro controls it
as dictated by the pilot.

Paul
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Old Sep 14, 2010, 08:45 AM
Go ahead... Build it to crash!
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Conroe, TX
Joined Apr 2007
2,630 Posts
Well I have rewound my motors and am nearly complete with a new tricopter build. Paint is drying. I have a question for you experienced tricopter guys. Have any of you measured the kv variance between the 3 motors on your tri's? After a rewind and some boca bearings, I have one with 652kv, one with 670kv , and one with 676kv as recorded with my Eagle Tree. 24/652 = 3.68% variance from the low to the highest motor. I am hoping this will be OK. My fingers are tired from the winding. Due to stator shorts, one had to be rewound 4 times and another one twice. anyway, I guess I'll fly and see. Hopefully the kv won't actually be too low with these. I was shooting for 700, but went a little under. I guess 11x3.8 props might be OK with this. Anyway, Just curious if anyone had measured their motors at all. I'll post my results once I actually get it airborne again.
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Old Sep 14, 2010, 10:21 AM
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Quote:
Originally Posted by Reflex1 View Post
I'm sorry, but both cynyam and talkthetorque's explanations are incorrect

The Gyro Only senses rotation which it corrects for without pilot input.

When you apply pilot input the speed of rotation is dictated by the amount of stick deflection , the Gyro works to control this.

This is the same in Rate and HH mode. Wind will have no effect on rotation speed (within limits of course,hurricanes excepted) the Gyro controls it
as dictated by the pilot.

Paul
ok
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