rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 632 ONLINE 38 EVENTS SEARCH REGISTER  START HERE
 
2 pages [ <<    <    ( 1 )     2     NEXT    >> ]484 viewsPOST REPLY
CarbonXtreme . Midland Helicopters . HeliProz

.
.
Aerial Photography and Video > HC Rigid erratic behavior
 
 
Disciple4123
Veteran
Location: Waynesboro, VA USA

I have been running Rigid for a while without issue on a Vario Acrobatic gasser camera heli. Today I replaced many of the the ball links and balls as routine maintenance. The balls are slop free, yet not tight in any way.

I flew it and it was fine at a govorned 1350 or so RPM. I turned the GOV down to 1300 or so just because I felt like it, and problems came about: after landing, idling for a moment, and restarting, the HC's HOR feature wanted to tilt the unit right hard. Then on a separate attempt it wanted to tilt forward hard. I corrected it each time by using the autotrim button, and flying cautiously. I do not feel that my replacing the ball links caused this, as things are good and smooth as they were before, but I could be wrong. I generally engage some HOR on the ground to prevent a tilt over under RIGID's influence, when HOR was taken out it was fine, when HOR was left engaged it was not. I am cautious not to accept a suggestion of "turn it back to 1350." as this machine is very smooth at either RPM, and that would be masking a problem.

The only deviation I have run from the manual, is running the mount with two vertical strips rather than 2 horizontal ones. This is done on a custom wood board mount for a reason, and it remains secure and gently dampened. I am about to make the mount with horizontal strips as recommended per Page 16 of the PDF. Any explanation as to why the strips shall be horizontal on all machines per the book?

I recall 2 different people having a strange effect similar to this, I think Trackhead was one of them, do we have any insight if there was a defect present, or just an operational issue?

Some guesses:
1) The autotrim is engaging on the ground to to some sort of glitch activity, when things are not level, throwing off the autotrim setting.
2) Horizontal strips make a difference.
3) Something is hamaged about the HC

I like to retain confidence in this HC, and things of this sort really cause me to doubt it.

Eric
07-10-2008 09:48 PM
HOMEPAGE  
 
 
Disciple4123
Veteran
Location: Waynesboro, VA USA

Well I set the sensor on a horizontal foam strip mount, and I adjusted blade tracking 1/2 turn on one side. Follow-up tests were very good, with no issues. I don't know what happened, but I hope I don't see the problem again.

Bear in mind that on Vario's 1/2 turn is barely perceptible, I check vibes by looking at the reflection on the camera's LCD, it always shows some horizon at close range if I tilt it right, and can perceive even the slightest. With that in mind, vibration is not an issue, I hoped for a more concrete problem.

Eric
07-10-2008 11:04 PM
HOMEPAGE  
 
 
clay454
Senior Heliman
Location: Ohio

i have experienced similar issues on ground and takeoff. therefore i only engage right after takeoff. no problems then. sorry so sloppy. driving to job in northern mochigan,

clay
07-11-2008 04:50 AM
HOMEPAGE  
 
 
Griffo
Senior Heliman
Location: Canberra, Australia

I have also experienced this when engaging horizontal mode (although the heli didn't bank hard, it just drifted faster and faster). I've tried autotrimming countles times but it's still a problem. I sent an email off to HC but never got a reply.

I'm now considering buying back my AP2000i.

I wonder if this may be a problem with the latest firmware? What firmware do you have and how old is the unit?
07-11-2008 04:59 AM
 
 
Disciple4123
Veteran
Location: Waynesboro, VA USA

The unit is from 1-2008.
The firmware is 1.34.3.0

It would stand to reason to engage some HOR prior to takeoff to prevent RIGID from maintaining an off angle and tilting abruptly when lifting off, now that I have had problems, I may do things differently. I should have left it in hard tilt, not autotrimmed it, and taken readings off of the computer on autotrim, see if the values were pegged. Perhaps spoolup vibrations mess with it, like the Micropilot autopilots that completely render themselves useless when the pull cord is started

I will re-iterate though, the final flights of the afternoon were flawless.

We need HC to establish a runryder identity to help us.

Eric
07-11-2008 05:11 AM
HOMEPAGE  
 
 
nooobs
Key Veteran
Location: Toronto, Canada

RE: Foam Tape

I've used several double sided adhesives and I personally haven't found a difference. Whether it's installed using strips in horizontal or vertical will not make a difference. I've even just used one big square double-sided 3M tape and stuck it directly on the frame without using the HC mount. No issues.

Eric what is your Rigid gain settings?


Griffo horizontal hold DOES NOT keep your heli in one spot and neither does AP2000i. The heli will drift with the wind and you have to correct with cyclic inputs.
07-11-2008 05:53 AM
HOMEPAGE  
 
 
Griffo
Senior Heliman
Location: Canberra, Australia

Thanks Noobs, yes I understand that. Position mode is useless and I have taped the sensor. I just find the AP2000i did a much better job of keeping the heli level and I knew that once I locked in calibration the AP2000i would hold rock solid in that attitude.

The HC unit appears to be unpredictable in how level it decides to keep the heli. It'll hold the heli perfectly horizontal one moment, then I'll fly around, hover again and re apply horizontal gain and it'll head off in a direction of it's choosing.

All tests have been in zero wind conditions and there is no payload movement in flight so I know that is not a factor.

Eric, yes mine has the same firmware and build date. Interesting.
07-11-2008 08:11 AM
 
 
trackhead
Key Veteran
Location: utah

Griffo,

I attributed my problems last winter with the HC to static build up and not proper grounding of the tail boom. Of course, who the heck really knows. But when I regrounded the boom, no more problems.

Last week in Aspen, after crashing into a tree and rebuilding the heli I had a bent motor shaft. I didn't realize it at the time, but the bent shaft was causing some sort of gnarly RF that also caused the HC to act very strangely. Eventually I swapped the motor out, and all was fine.

The HC works best in slow flight, or hovering. After fast forward flight, banks, etc, it does not put the heli back to a perfect hover. I mainly use it as an assist to help me fly a little further beyond my visual comfort range.

Anyway, not sure if any of that helps.
07-11-2008 03:54 PM
 
 
Disciple4123
Veteran
Location: Waynesboro, VA USA

I run double ground straps on the tailboom (incase one breaks). Yesterday was hazy humid, so static, if present, should have been dissipated.

I guess we can conclude that the HC is rather static sensitive. I had a hard roll right (crash) in the winter when runnign twin engines, and since went to a single. Perhaps they can work that out, I hate to see minor lingering problems in an otherwise good product. With the economy right now I won't be going Carvec for a while, I thought 2007 was going well with AP, but 2008 is near hibernation around here


Noobs: My Rigid runs at 7/7 with the servo balls 13.5mm out (sensitivity is directly related to servo ball location of course) I can get away with 8/8, but it's a little smoother and still solid at 7/7.

Eric
07-11-2008 04:55 PM
HOMEPAGE  
 
 
nooobs
Key Veteran
Location: Toronto, Canada

I use to cover the part of the HC unit where the static is coming from with foil. It's simple and it works. If you're placing the HC unit near the plastic main gear or belt then you'll have to block the static.

I've moved all my electronics since then away from the main gear.

My Rigid is at 6/5.
07-11-2008 05:00 PM
HOMEPAGE  
 
 
trackhead
Key Veteran
Location: utah

Noobs,

I'm not catching your drift on static/foil?

What are you doing?
07-11-2008 05:10 PM
 
 
nooobsKey Veteran - Location: Toronto, Canada -
On any spinning plastic components like plastic tail blades or main gear there is a static build up in those areas. If you were to take a voltage detector you'll notice that you'll pick up static.

I didn't realize this at first until I got myself a voltage detector. My father, an electronic geek, told me back in the sixties he solved a similar problem by covering the unit with foil. So I did the same and it worked.

But anyway on my MJ2 I've moved all my electronics away from any source of static.

07-11-2008 05:16 PM
HOMEPAGE  
 
 
Disciple4123
Veteran
Location: Waynesboro, VA USA

Yes, noobs is right, there is a triboelectric standard to all materials, if dissimilar, they will charge when they pass by each other, some plastics are near the ends of the spectrum and charge heavy, steel is near the middle of the chart, etc.

One thing I do is spray a can of static spray for garments over the whole heli lightly perodically, it may help. But the summer is usually not the time for static to build up, cold winters are when sparks fly the most.

So the following for a triboelectric chart and details.
http://en.wikipedia.org/wiki/Triboelectric

Eric
07-11-2008 05:34 PM
HOMEPAGE  
 
 
trackhead
Key Veteran
Location: utah

Yeah, I had the worst glitches in winter, when flying up in the mountains.
07-11-2008 06:58 PM
 
 
wjw
Senior Heliman
Location: Cape Coral, Florida usa

Those weren't glitches, just too cold to feel your fingers
07-11-2008 10:28 PM
 
 
Griffo
Senior Heliman
Location: Canberra, Australia

Thanks guys this is all very helpful info. I have grounded the tail to the boom but that's it. I'm flying the Logo600 with plastic frames so I never thought this could be a problem. I'll make a few adustments and see what I find.

Track, yes I think you're right. The HC never holds a level hover after forward flight. It seems to put the gyros off centre.
07-11-2008 11:32 PM
 
 
tech1
Senior Heliman
Location: Mississauga

I'm not so sure about tail blades etc. build up enough charge to be a problem. Static builds up faster when 2 different materials are rubbed together. Your tail belt is a big contributor which is why it is recomended to ground the tail boom to the main frame of your heli.
The idea is to keep the entire heli at the same charge level. That way there will be no potential difference to initiate sparks.

Plastics can be made conductive so that the case takes the discharge instead of the internal electronics. (same as wrapping the part in foil) Don't quote me here but I think I read about the GY401 using this.
07-11-2008 11:41 PM
 
 
Crazy-Joe
Heliman
Location: Germany

Hey guys,

seems I am too late, everything is discussed already and the main point (statics) is mentioned too. So, Eric, did that solve your problem? Cause this really is the one reason for the HC (or more concrete the servos!) acting that strange: electrostatic charge. See also manual page 17: "Electrical earth".
Second issue: yes, the internal horizon can drift after faster flights, turns, etc.. This is also mentioned in the manual. But after holding the HC for a few seconds, the drift should disappear again and the HC should work as desired again. For trimming please see manual pages 30/31. There are some hints that should help you.
And also described totally correct already: the horizontal mode will never keep the heli fix over one geographical point! This is the job of the position mode only. And that is also why the HC is not named a real auto-pilot as the heli does not become a fully controlled UAV by using the HC. The HC is a stabilisation help, kind of an assistant, as mentioned by trackhead already. Without reference points like GPS (a little too imprecise) or other possible systems for example with a reference signal from a ground unit, it will not be possible to create the perfect virtual horizon. But I think the HC does a good job in general.

Griffo: If there was a not answered mail, please send it again as I did not get any mail from you regarding this and, sorry, unfortunately I do not find lots of time to read in here

Cheers,
Joe
07-18-2008 08:54 AM
 
 
Griffo
Senior Heliman
Location: Canberra, Australia

No worries, thanks Joe. I'll resend it.

I've removed the HC unit from my AP heli and replaced it with the AP2000i. I can't have the horizon level drifting on me as I climb for altitude.
07-18-2008 09:04 AM
 
 
Disciple4123
Veteran
Location: Waynesboro, VA USA

Crazy-Joe, thanks for your quick response. Manufacturer's that post on forums get extra credit from me, as I appreciate it.

I have had a very good groundplane including double grounding straps for the tailboom, torriod chokes on most lines, and anti-static spray applied regularly. All of these measures were already in place the day of the issues. Additionally the day was humid; less chance for static.

My experiences with HC have been good enough that I am keeping the unit, but some developer investigation into that erratic day when it wanted to, and almost did, roll over would be nice.

Lastly, is there an altitude hold device, and GPS add-on for the Profi coming soon? An altitude hold device would be very appreciated

Thanks,

Eric
07-18-2008 01:35 PM
HOMEPAGE  
 
 
2 pages [ <<    <    ( 1 )     2     NEXT    >> ]484 viewsPOST REPLY
ZoomsHobbies . HeliHobby . Ron’s HeliProz South

.
.
Aerial Photography and Video > HC Rigid erratic behavior
  UPDATE SCREEN   PRINT TOPIC Advertisers 

Subscribe to This Topic

Sunday, September 7 - 4:39 pm - Copyright © 2000 - 2008 runryder.com | email | link to rr | runryder needs cookie