S800 / WKM / Z15 : ideal WKM gains? Is FW5.20 reliable?

[MombasaFlash]

There must be a whole load of bog standard S800/WKM/Z15 setups out there and I suspect that very few folks use the default gain values as they all seem a bit high and possibly too reactive for AP. How about those with this standard setup posting their gain settings so that we can get an idea of the mean values? Naturally there will be a few differences according to LiPo size and weight, plus any other mods, but a ballpark average guide for this particular platform should become apparent after a while.

Below are my 'Auto-Pilot' settings:

210 : Pitch
210 : Roll
120 : Yaw
195 : Vertical
130 : Attitude Pitch
130 : Attitude Roll


Another thing. Atti mode will make all the calculations it requires to hover with the Tx stick at (or around) 50%. Manual mode requires around 70% Tx throttle - with my current settings. This means either a drop, when switching from Atti to Manual, or an increase in altitude when switching from Manual to Atti.

The manual states that the 'Vertical' parameter has no effect upon the Manual mode so the question is, is it possible to configure WKM so that the two modes have a similar hover throttle stick setting and thus reduce this differential?

Third item. I went back to FW5.16 from 5.18 when the latter made no difference to the altitude loss issue that is a current hot topic and which also affects FW5.16. The problem really only appears with a bit of wind. Is this altitude loss thing resolved or improved in FW5.20? Or is it still a haphazard condition that does not affect everyone?

This is partly why I have started this Gain Settings thread, to try and isolate conditions under which altitude loss could happen.

 

[olof]

130 130 140 160
120 120

These are the gains I have used ever since 5.16. They are very smooth. I got them originally from Patrick at AerialMediaPros.

They work great even on 5.18 and 5.20. 5.20 is a little slower but smoother at stopping a decent, it is fine as long as you are ready for it. I always try to fly really smooth when shooting. If descending fast I start coming in with the throttle 30-40' before I want to stop, this way it is smooth and you don't have to do a quick burst. Getting behind the power curve is how you crash, I learned this flying GA aircraft and RC models as well. I keep low rates on my RC planes as well, it makes you smooth.

I have never had a problem with sudden drops, but I use a lot of caution when descending, I fly at 6.95Kg.

I also never use manual. I use Atti 90% of the time. GPS is good for holding setting up a shot, but I pretty much always "film" in Atti.

I don't like having manual on a switch because it can cause the drop you mentioned. I don't want to hit it by mistake.

 

[hjls3]

Mombassa - my gains are right there with yours, after much tinkering. I have flown both 5.16 and 5.20 and had the altitude drop happen in both modes. I have noticed in disturbed air that its more likely to happen - decent or windy. I am very careful nowadays about how I bring the bird down. Which leads me to my point - I think the altitude drop might be related to loaded S800 Z15's and vibes getting to the IMU (no matter what the firmware is). Without the ZEN I can not make the altitude drop happen. Making me think that the S800vibrates too much when loaded and those vibes are getting to the IMU. To combat this - I have recently ordered the Kopterwork stabilization kit I saw in your video. Also, I have noticed a DJI vid that the IMU is re-located to the Landing gear assembly to take advantage of the new anti vibe system they have. Just my thoughts....here is that video...of the IMU re-located. - (26 seconds)

http://www.youtube.com/watch?v=Sw5gJ1hzhHg

 

[MombasaFlash]

Interesting video from DJI. Like the first comment "Great, more stuff we need to buy to get the S800 to work!".

Not really sure why everyone is bitching about it. Treat it as an upgrade following development. Happens with everything. I'll get it as soon as it is available.

I have tried isolating the IMU from airframe vibes with two different density gel layers - even drilled another hole for the barometric pressure reader because I am damned if I can find the hole that is supposed to be there - but neither has changed its habit to sink now and then. Cannot even pinpoint specific conditions when it happens. It is pretty random, but more likely with, as you say, "disturbed air'.


BTW, I'm with you on the Manual Mode thing. Who needs it at all?

 

[hjls3]

I have always kind of wondered why the cutout for the IMU is barely big enough to fit the IMU. Even though my IMU is not touching the top plate - is it close enough to introduce vibes to it???

Im with you - its development. With that said - lately I have been considering moving the ZEN and WKM to another bird - if the Kopterworx kit doesnt greatly reduce the vibrations - i think my ZEN is headed elsewhere.

 

[MombasaFlash]

I will wait for these new u/c damper fasteners and evaluate them. I only bought the complete S800/WKM/Z15 package because the Droidworx XM etc kits were not available to buy right at the time I needed it for the Kenya trip. The WKM has many good points, with its easy to install modular design, but there is plenty I do not like about it. The instability of the firmware for one, their interpretation of Return To Home is very disconcerting with the S800 swinging its nose around, instead of the MK way where it returns to base without changing its nose-heading.

The Z15 software is extremely restrictive. Generally speaking, the single saving grace of the Z15 as it is now is its stability, as there are several essential functions that simply are not there. The inability to change the axes to proportional behaviour makes it pretty lousy for one-man operation. I do not have a problem with the limited camera suitability, as I would be using the GH2 anyway.

The retracts issue remains unresolved as far as I am concerned. The DJI option is too heavy and the Secraft items ALL suffer from vibration, mostly in the down position. Kopterworx has a new retract option that I will be trying out. It at least has the hinge supported in two places and therefore might be less prone to wear and eventual looseness and consequent wobble.

If the WKM issues are not resolved pretty soon I will be looking to return to a Droidworx airframe with MK flight control - because in my view MK is compact, mature, predictable and reliable - and I might consider retaining the WKM purely for camera mount control of the Z15 until the direct-drive gimbal explosion provides an alternative.

I will not consider the CineStar in any shape or form. Not that it is not a very good airframe, it is excellent, but I am shocked by the attitude of Quadrocopter. I am currently in Atlanta GA and have been helping a friend set up his heli and CS8. The CS8 was displaying some strange behaviour so I called up Quadrocopter. But, much like the US departments of Homeland Security, Border Control and Customs, I was left with a sense of "have a nice day and f**k you very much". Very evasive on the phone with setup queries and ultimately unhelpful. Happily, the CS8 has been sorted out but with no thanks to the manufacturer.

Pretty shameful attitude they have and an opposite pole from the likes of Quadcopter UK or Kopterworx, who actually try to help with the gear they have made money on by selling to you.