START HERE |
|
Register | FAQ | PM | Events | Groups | Blogs | Calendar | Mark Forums Read |
Unregistered
|
Align 3G FBL System Align 3G FBL Flybarless System Software and Hardware Support |
|
LinkBack | Thread Tools | Display Modes |
Sponsored Links | |||
Advertisement |
|
12-18-2010, 08:23 PM | #442 (permalink) |
Join Date: Dec 2009
|
Here's the second test flight of my 500 after lowering the swash mix settings after dir...I need to redo the setup to get max potential outta the system... But here's me ecstatic about a properly flying heli... Alot of my moves are still work in progress, and I'm
not gained right for a piroflip... It's all choppy... But here's me as a happy camper! Better vids to come! [ame]http://www.youtube.com/watch?v=349UxQKSxdE&feature=youtube_gdata_player[/ame] |
12-18-2010, 09:15 PM | #443 (permalink) |
Join Date: Dec 2009
|
[ame]http://www.youtube.com/watch?v=rP-G1xhqHco&feature=youtube_gdata_player[/ame]
|
12-19-2010, 12:41 PM | #444 (permalink) |
Join Date: Jan 2008
|
We have done this Mod to 3 3g Units and with a few pointers on software programming from Leon . The machines are flying REALLY GOOD!!
Big Thanks to Leon for these updates! |
12-20-2010, 11:16 AM | #445 (permalink) |
Registered Users
Join Date: Aug 2009
|
Following up my previous post, I have stiffened up the frame on my T600 fitted KDE bearing blocks & a 3rd bearing & re-worked the electrics. There was a vibe to work out which was tailshaft (new & bent), torque tube, ditto & badly meshing gears on the auto rotation gear. The gear mesh took a little work but is now smooth. Finished off with Edge FBL blades.
Re-set the head & 3G using Leons settings & it flys great. Didn't push it today as it was -7ºC with a breeze but looked really good. The doohicky with the hex driver hanging out is to set the elevator zero. Using the KDE blocks I fitted the shaft collar upside down to get a bit more swash travel. Thanks again to Leon & Jondabear for all their work on our behalf.
__________________
T600N DFC Brain. T700N CGY750. T600 ESP BeastX. Futaba 8FG (Link once & forget) |
12-20-2010, 12:02 PM | #446 (permalink) |
Registered Users
Thread Starter
Join Date: Oct 2004
|
Glad to hear its working!
__________________
Representing: Team A Main , Mikado V-Team, Team Xpert, Team Synergy, Team KDE, Team Cool Power, Team Hatori, Team Protek, Eco Power Lipos, TruGlow, XFC 2006/7/8/11 |
12-20-2010, 12:37 PM | #447 (permalink) |
Registered Users
Join Date: Nov 2010
|
Make sure you ask for latest stock when ordering
I bought a 550E flybarless a couple of weeks ago and the sensor is marked 2.1 and has all the mods here done to it. It's essentially "potted". I also bought a 3g upgrade for one of my t-250's at the same store at the same time and only to find a few days later that it was a V1 with no mods. The firmware upgraded ok but I'd rather have the latest version of the hardware. Of course, the store I bought it from has a no return policy.
Anyhow, a word of advice, make sure you check that you are getting the latest stock when you buy a 3g. If the seller won't let you check then go elsewhere. For their own good Align should be making sure their dealers have latest versions and are not selling down rev hardware. Ron |
12-20-2010, 04:25 PM | #448 (permalink) |
Registered Users
|
Don't worry about the "V1" tag.
I had very early V1 hardware in my 700n, did the firmware update as it came available, did the mod, epoxied the pins. It has performed flawlessly since day one.
__________________
T-rex 700n VBar 5.3 Pro | T-rex 700e V3 VBar 5.3 Pro | JR DSX9 Limited Team RCBits | Team Lynx |
12-22-2010, 03:19 AM | #450 (permalink) |
Registered Users
Join Date: Nov 2010
|
Thoughts on 3g sensor mounting (an engineering perspective)
It's nice to have found this mod. Very surprising that Align would even go into production without doing enough testing to find this out ahead of time. If I had been one of the early adopters and had all the problems that so many have had I would have been more that a little irritated.
One has to wonder if Align is going to officially sanction this mod. Anyhow, I've been doing some testing with both the 3G and the Skookum 720 as well as having a look at the V-bar. One of things I found is that the 3G has considerably lower installed mass (when installed with included metal plates) than some of the most popular Flybarless controllers and that makes the 3G far more susceptible to high frequency vibrations that other, heavier sensors. For 3G it is about 13-14g while for the 720 it's close to 30g, and the V-bar is about 20-25g (I estimated based on their specs for the plate). Note also that Mikado seems to have it's fair share of vibration issues and say in their help forum they install a plate on all their ships (but they don't give you one apparently). More mass is good because it effectively creates a low-pass filtering function IF the device is mounted on semi-flexible tape that has minimal high frequency transfer to the sensor. Stiffer and thinner mounting tape effectively raises the frequency of vibrations that will be transferred to the sensor offsetting the value of the extra mass. Of course, too soft of tape will be detrimental also if the sensor flops around due to maneuvering. This will generate unwanted lower frequency events when the sensor decelerates as it hits the limits of the tape compression/expansion . As well too much mass will start to affect the top-end of frequencies we care about (lower frequencies) as well as weighting the helicopter down. How much mass should be added is a function of the tape stiffness, how and sensor mass needed to dampen higher frequencies without significant impact to lower frequency, desired motion all within a proper CG and without sacrificing significant performance. So, effectively, more sensor mass and semi-flexible tape has the effect of decreasing the sensor gain for higher frequency vibrations with minimal effect on lower frequencies (the one's we care about). Finally, some of this detrimental higher frequency vibration can be filtered out by the DSP processor in the flybarless controller. The effectiveness is this is entirely a function of the processor's performance which is limited by size and power consumption. So, faster processor means better unwanted vibration resistance - assuming the firmware designers did their job right. Of course we have no control over this except with our pocket books. Anyway, the bottom line here is the 3G has relatively low mass compared to the competition which makes it more susceptible to higher frequency vibrations which is likely the reason this silicon reinforcement mod makes so much of a difference for so many (dampens higher frequency vibrations). While there are other factors (like distance from the axis' of rotation - i.e. the rotor shaft), I decided to experiment a little and increase the overall mass of the 3g sensor installation so that it is closer to the 720 and about the same as a V-bar. To achieve this I used a thin layer silicon rubber to glue three of the 3G metal plates together (about 16g) and then used very thin servo tape to secure that assembly to a sensor with the mod from this thread. I then mounted the entire assembly very near the main shaft (on a t-250se) with one of the square tapes that come with the 3G kit making sure there was well supported slack in the cable and that nothing was touching any part of the frame except the bottom of the assembly. Why didn't I mount it directly under the main shaft (on the T-250 it's possible)? That position puts it only about 10mm from the motor and I'm concerned about magnetic interference with the gyros. So, what did it do? Well, I'm not a 3D pilot - yet - so no testing there yet but I found that the little ship was almost hands-free stable in a hover and very stable and predictable in forward and backwards flight whereas previous to adding the extra mass it was an extremely squirrely little helicopter in all modes of flight. I haven't tweaked any of the software parameters but I was able to turn the external gain pots up to around the 1-2 o'clock position. Eventually, I'd like to get someone who is an accomplished 3Der to check it out but so far I'm very pleased with the obvious improvement between modified sensor with only one plate versus modified sensor with three plates. One last thing. The little gyro platform on the back of the T-250 is about the worst possible place to mount ANY gyro. That cantilevered plate is just like a tuning fork. Ron |
12-22-2010, 03:29 AM | #451 (permalink) |
Registered Users
Join Date: Nov 2010
|
One more thing. All this seems to contradict the fact that some have seen better performance strapping it down tight. I can offer two theories on this: 1. Strapping it down compresses the sensor case ever so slightly and just enough to dampen the vibrations of the small tangs inside the case banging against the sensor boards (on unmodified sensors). 2. The strap, because it's flexible, dampens some of the high frequency vibrations.
Ron |
12-22-2010, 06:04 AM | #452 (permalink) |
Registered Users
Join Date: Mar 2009
|
glueing plates
Hi Ron,
thanks for your input,would it be o/k to glue the plates together with E6000 or should I use JB weld, Many Thanks, Marty. |
12-23-2010, 03:24 AM | #453 (permalink) |
Registered Users
Join Date: Nov 2010
|
Neagron,
Use whatever holds it all together securely so it's solid and won't come apart and doesn't make a mess. Please remember I'm just experimenting and can't be sure if this works better for all phases of flight. YMMV. It would be good get some more experimentation going on by others. Another major issue I see is there are SO many variables - build technique, servo speed and torque, gyro mounting position, the list goes on. Because if this it's near impossible that any improvement will fix everyones troubles. Another thing I'd like to experiment with is how mounting the sensors farther away from the mainshaft changes things. There is one line of thought that says if the sensor is e extremely sensitive to vibration that it might be better to have it further away. This is like having it out on a stick where a little bit of movement on one end translates to a much larger movement on the other end. This might allow turning down the gains so the sensor is less susceptible to vibration but still sees the movements related to the airframe. Once I get to a stable set of gain settings I'll try moving the sensor farther back to see what difference it makes. Cheers Rin |
12-23-2010, 10:13 AM | #454 (permalink) |
Registered Users
Join Date: Nov 2010
|
Hey, one more thing that came up yesterday - was getting random "hits" to the receiver where everything would just twitch once and then go back to normal. Turned out to be static discharge from the tail drive belt. Belt driven TRs are just like a Van DeGraf generator (google it). Grounded the tail boom to the frame and to the negative post on the battery. Twitch gone. Plenty of posts about this on this forum and others so not a new discovery. Just something I missed during the. build process. I believe the 3G install manual mentions this as well.
|
12-28-2010, 07:41 PM | #455 (permalink) |
Registered Users
Join Date: May 2009
|
Thanks for all the info, guys.
I've had a 450 sitting on the shelf for about the last 6 months, just too small to have fun with, and you almost need a microscope to rebuild the flybar head. So, I decided to get a 550 Flybarless, with the 3G setup. I also decided to put the SK-720 on the 550 and put the 3G setup on the 450. That should be a good system to retrain on before I try out the 550. I found an Align FBL head today, so in the next week or so, I should have enough parts to get both helis in the air. I'm still a newbie on helis, hoping that I can dial the throws down enough to keep them in one piece for a little while longer! |
01-02-2011, 05:29 PM | #456 (permalink) |
Registered Users
Join Date: Apr 2008
|
Looks like were on the rt track. Just remember though, alot of the 3g suggestions we give have come from THOUSANDS of PERSONAL flights and testing.
No theory here. If I havent tried it and found it helpful.........and then retried it and found its weakness'........I wont suggest it. PEACE! |
01-02-2011, 06:39 PM | #457 (permalink) |
Registered Users
|
I'd just like to post my initial results.
First, some history. Back in Sept, I planted my 700e hard.. sideways.. about 600 clams worth of pain. I gradually rebuilt it over the next month or so. None of the electronics where damaged or even came close to taking a hit. While the heli was in the hanger for repair, I did the mod, (removed the tabs and used red ultra Hitemp RTV sparingly) and mounted the sensor on 1 layer of stock foam, unstrapped. Previously it was strapped hard. I changed nothing in the 3G either with the dials or the software. I did not even run setup again. The heli was flying ... fine.. for my skill level before this, but now it has picked up what I can best describe as ground resonance. Today, on the maiden flight, it cost me a set of tail blades. When i tried to lift off, the heli seemed quite unstable on the ground and at first wanted to lean right Once in the air it was fine, I can't say that I could tell any difference in the way it flew. It was not overly windy and the temp was a balmy 47 deg F. When came in to land, I hovered it at about 3 ft and cut power to float it in. As soon as it touched the ground, it became a handful, wobbling severely like it had a balance issue. as it spooled down, it tipped to the right and I could not bring it back. Everything is OK except the tail blades which are royally chewed. The mains dug into the damp grass field and suffered no damage but 1 of them was severely looser than the other one in the grip after the event. Either it loosened up in flight or it loosened up on impact. Anyone notice something similar?
__________________
-Michael |
01-02-2011, 08:22 PM | #458 (permalink) |
Join Date: Dec 2009
|
You must reset the 3G after a rebuild/remount. In the DIR mode the 3G finds center... Once flying, the 3G can correct for a lot, but on the ground it's trying to center at a false center from a previous setup. Just my opinion.
|
01-02-2011, 09:02 PM | #459 (permalink) |
Registered Users
Join Date: Jun 2010
|
do you have to reset the system if you do the sensor mod?
__________________
Trex 700E DFC V-Bar , Trex 600N , Logo 600 SE FBL V-bar, Logo 600/550 FBL V-bar,Logo 400 FBL V-Bar ,Goblin 500 V-Bar, Blade 130X , Blade MCPx , Blade 500X |
01-02-2011, 09:28 PM | #460 (permalink) | |
Registered Users
|
Quote:
I'll give it a try when the blades show up and the weather breaks. I also plan to set the pots lower at first... and practice some more on the sim, since I felt veeeery rusty today
__________________
-Michael |
|
Thread Tools | |
Display Modes | |
|
|