Taranis + Kiss thoughts and questions

[PsyBorg]

Well I have jumped on to the Taranis bus recently and picked up a Taranis Plus and an X4R
receiver to go with it. I have a few thoughts on this, the kiss set up and the Alien frame
and what I have observed with using them.

First I will start with the newest acquisition the Taranis. I will compare it to my Devo7 as that
is my only radio I have flown quads with. The old Futabas and Sanwa systems were old school plane
and heli radios and FM so nothing in the same realm to compare. The weather has been crappy up until
this past weekend where both days were nice enough to go fly outside so the first days were all on
the sims.

I am getting used to the subtle difference in size and weight so that was a very minor hurdle. The
plastic casing seems "thin" compared to the Devo and maybe that is nothing but a weight issue but
it feels different and I have less confidence about it taking bumps and knocks compared to the Devo.
I liked the fact it came with a four hole strap hook to balance the radio and help manage the hand
stress +2 for that. The software to set it up... all I will say is Uhhhg. I got thru it and now am
reasonably familiar with most of its operations. Thank God for FT forums and you tube. Other wise
I dont believe this radio will have ever gotten so popular. The plus side is I agree that this thing
will do nearly everything short of cooking and cleaning house.

How it flew.. In the sims I use it is easy to set up and has upped my game as far as my abilities.
The only thing I did not like is the usb port on the back of the radio. I feel it would better serve
me any ways to have the port on the side or even the top instead. I am not sure but I think this has
a higher resolution digitally then the devo 7 but that had to be interfaced thu an analog converter
to use for sim flying so that could be the loss of the finer control. I think I will have to open it
up and find better spring resistance to the sticks as I always feel slightly off when using the
Taranis. For now I will leave it as is and see if that goes away.

When I finally did get it out in the real world on a real quad I noticed more how much more smooth it
was specifically how I can make finer pitch changes and not porpus or have to cut throttle to drop
down into a better gate line. Now to qualify I will say the quad is set up exactly as I had it with
the Devo 7 as far as rates and pids. The only change I did was actually set expo on the flight controller
and not in the radio like I did with the Devo. I will have to change my rates higher but that was in
the plan anyway as I had progressed past what I had set using the Devo.

Interaction with the KISS FC on my Alien build. I am not overwhelmed as much as I thought by all the
hype as I anticipated. It has good points and bad but this is not a nitpick it to death thread. The
one MAJOR issue I am seriously not happy with is the fact I now have mid throttle oscillations really
bad. The Quad shakes worse then a chihuahua now where it NEVER did that before on the Walkera setup.
Now that said, I was running ppm not sbus so THAT may be what is the root cause of the mid throttle
shake n bake.

Lastly as this is kind of long winded Is an overview of this set up and the questions that have come up.
With only 10 packs in real flying vs probably a good 25 hours already of sim time with it I think it
is a step forward. The minor problems with it for me can be cured over time. I think I will look into
repainting it and using a textured paint to solve the grip issues. While it is open I will change spring
tensions to get the feel I am used to. More time programming and changing things will help with the
software dread I am sure. Now for questions.

First and foremost is those mid throttle oscillations that I now get. I will post some video of the
same track I used in my last video where there were no oscillations to show how bad they are. That
brings up the question of the oscillations caused by the Taranis / sbus protocols and NOT the KISS
FC or software that runs it. If I did not have them on PPM using Walkera gear and the only thing
that has changed is the radio and receiver that kind of points in "A" direction for the developers
of both KISS software and the Taranis / open TX devs to look to solve a common and predominant issue.

Second has anyone come up with a viable fix thru tuning to get rid of all or most of these shakes.
I know Steele and the RR crew that use KISS setups managed to do this but they have years on me for
tuning. I am already very similar to what Steels posted pids are by using Skitzo's tuning method but
I like many others have them.

Third is how come this quad does not seem to be as fast as others in videos I have seen. Is the
weight difference for the 5x4x3 props spooling faster enough to change top end verses 5x4.5x3
heavier props. Do the motors lose that much rpm from the added weight? Also what is an avg top
speed in MPH for the stock RR Alien 5 inch build with the KISS setup and the Lumenier 2350 motors?
I figured someone would have clocked them with a radar gun but I cant seem to find any results.

Well that's long winded enough to hopefully drive some discussion and maybe help me learn some more
as well as answer them for others I am sure are scratching their head as well.

 

[mikeporterinmd]

"I think I will have to open it
up and find better spring resistance to the sticks as I always feel slightly off when using the
Taranis. For now I will leave it as is and see if that goes away."

If you have a new radio with metal crossbars (just because you bought it new doesn't mean it is newly made), then you can install heavier springs that I got from alofthobbies. Otherwise, you should replace the sticks with the newer ones ($13 each, I only did the right side, mode 2) and then use the heavier springs. However, newer sticks are coming with "Hall Effect" sensors, so you might want to wait until they come out. Initial price is $20.

Mike

 

[mikeporterinmd]

"I think I will have to open it
up and find better spring resistance to the sticks as I always feel slightly off when using the
Taranis. For now I will leave it as is and see if that goes away."

If you have a new radio with metal crossbars (just because you bought it new doesn't mean it is newly made), then you can install heavier springs that I got from alofthobbies. Otherwise, you should replace the sticks with the newer ones ($13 each, I only did the right side, mode 2) and then use the heavier springs. However, newer sticks are coming with "Hall Effect" sensors, so you might want to wait until they come out. Initial price is $20.

Mike

 

[LitterBug]

PB,
Always fun to start down a new path and have a new learning curve I'm running Spektrum and can't comment on the Taranis specific issues or config. Oscillations should not be TX related, but rather FC/PID related. (unless the pilot is oscillating the sticks) (been there done that). I do all the expo config on the FC side and run straight stick positions on the TX/RX. TX/RX is just switches and gimbals. FC is where all the config is done.

What camera angle are you running? Higher angle usually translates to higher speed.

Cheers!
LitterBug

 

[PsyBorg]

Well I kind of thought that too LB. Specially when Snarls and I were talking about mid throttle oscillations shortly after I first set mine up with the Devo 7 and I did not have them but Snarls did with the Taranis setup. I thought that right up until the time I swapped over to the Taranis and Sbus with no changes to the quad other then putting in a new receiver.

Traditional thought dictates that if a problem was not there before the changes that the changes is what cause the problem. Its like putting on a motor with a bad Bell. The motor is new and the oscillations started when the new motor was installed. Its the motor not the pids. Same thing. Ehh but who knows... I am no longer sure the way I think is normal anymore so I am probably wrong. Next decent day I shall save these settings and retune from scratch.

As far as angle goes I am somewhere between 35 and 40 degrees. At least going by hole count in the camera mount anyway. That still does not change the fact that wide open throttle seems less then cruising speed on video compared to like the RR crew or others that fly Aliens with the same setups. Also the fact that WoT shows the system drawing 63 amps which seems low. Look at your own amp draws at WoT your pulling what mid 80's into 90s at times?

Maybe its just a perspective thing because I am not using the same lens's or camera to film flights. I know I can see a difference between the 2.1mm lens I have on my board camera vs what ever is in my HD flight camera. The distance looks short and squatty compared to the board camera where it looks more true to actual distances. That may be due to 4:3 vs 16:9 as well.

Still even without video comparison it seems slow to me. Maybe its in my head as I am used to faster speed from riding dirt bikes as a kid to racing cars as a semi adult. Anyway I will upload a flight from Sunday to show the difference between what I did before on the same track pre Taranis vs this past weekends flights doing the same thing. Ill add the links after the uploading is finished.

 

[LitterBug]

PB
Check to make sure your stick end points are where you think they are in the KISS software. I know on my Spektrum, default range is not 1000-2000 and I have to set the throws to 150% to get full range. Maybe there is something like that on the Taranis too.

Cheers!
LB

 

[Snarls]

I think I pull around 90 amps full throttle, but I haven't really done any full throttle runs so I can not confirm. One of the reasons the RR videos may look faster than your vids is due to the lens like you suggest. RR and others commonly use superview on their GoPros and the super wide angle makes the sides move a lot faster.

I have not been able to fly much lately so I can not say if I still have mid throttle oscillations.

 

[PsyBorg]

All the standard setup is spot on. Even with the Devo 7 it was. With that I had to extend the travels out to 125% to get the Devo centered at 1500 with end points at 1000 and 2000. The Taranis only needed a few points to center and the end points are and stay right at 1000 and 2000 on their own. Either way both set ups top out at 63 amps. Now to qualify that I will say my current sensor is from the pnp50 which I hear only reads to 50 amps, I also just read it reads up to 200 amps but the 50 amp range is its proven accuracy.

I guess all I can do is start over with a full retune and see where that gets me. I have been thinking more on this and am wondering if TPA would be the issue holding it back on the top end. As I understand it Pgains to a certain extent also produce the speed in which the motors do things. To do this the motors have to spin up faster. TPA adjusts pgains proportional to throttle by dropping the P gains up to 25% of its total with that 25% managed by what you set the parameters to. I am wondering in tuning out wobble on punch outs if I tuned out the available top end range in the process.

 

[PsyBorg]

Well got the footage uploaded to show the difference with just making the radio change. Don't mind the crappy flying I was missing the gate a lot due to the feel of the Taranis gimbals vs the Devo 7's. I opened it up and resolved that last night. On a bright note I finally got the sound worked out on the pnp50 for it to be usable on dvr footage.

Note the area after the gate where I do the double cut back around the flags before the straight run as well as the start of that straight section. That is where they show up really bad. The only thing that was changed was the receiver and radio nothing in the setup other then some expo for pitch and roll on the FC was done.

Here is the same course with both HD and dvr footage with the Walkera set up.