allista

[1.7] Throttle Controlled Avionics

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It is kind of weird what KSP will let you do.

You can not leave a flying vessel in atmosphere and return to the space center.

You can switch between nearby vessels in atmosphere, and while throttled up, with the [ and ] keys.

Here's a test of some formation flying where I do that.

http://i.imgur.com/c5uvFLj.jpg

D.

Brilliant! And I've always thought that it's impossible: several times tried to switch with [] between a ship and its last stage both returning from orbit. Always saw the "Cannot switch while in atmosphere" message. O_o

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I'm not sure I understand your proposal. Could you post a picture or a .craft file of the vessel in question and describe which engines you want to control differently and how in particular?

I think what he means is two separate sets of engines and throttles: one set for vertical lift and one set for forward propulsion. By having independent throttles he can maintain his altitude with the lift engines and increase or decrease his speed with the other engines. For instance I have a large helicopter with four main rotors for lift controlled by TCA and two jet engines for propulsion which are manually controlled. To be honest though I just use Davon TCS for the independent throttles. I agree with his issues with it but it works fine with TCA so there's no real reason I think, to duplicate its features.

Unless of course it doesn't get updated for 1.0.

Edited by Adyx

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It is kind of weird what KSP will let you do.

You can not leave a flying vessel in atmosphere and return to the space center.

You can switch between nearby vessels in atmosphere, and while throttled up, with the [ and ] keys.

Here's a test of some formation flying where I do that.

http://i.imgur.com/c5uvFLj.jpg

D.

As long as the operating vessels stays loaded (close enough to the physics sphere; more than 2.5km now?), the game won't have problems calculating the TCA physics.

It would be interesting to watch you fly one of these rockets away from the others' physics sphere, and see what would happen when those other rockets unloaded, though. :)

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As long as the operating vessels stays loaded (close enough to the physics sphere; more than 2.5km now?), the game won't have problems calculating the TCA physics.

It would be interesting to watch you fly one of these rockets away from the others' physics sphere, and see what would happen when those other rockets unloaded, though. :)

In KSP 0.90 I'm pretty sure they'd be destroyed as debris once they left the physics sphere. This is from a test where I kept control of the vessel that stayed hovering and launched one of the other in that picture towards the sky, the one I launched was destroyed as debris once it left the physics sphere. I assume the same would happen if the setup was the other way around.

In KSP 1.0 with the physics sphere changes, who knows?

D.

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NICE! I never thought this was possible.

edit: please add this to CKAN

Edited by Tahib

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NICE! I never thought this was possible.

edit: please add this to CKAN

It is on the CKAN which should update its database soon (I've just published the update).

If not, please report back -- CKAN is prone to many errors during automatic updates.

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Thanks allista.

Truly a great mod. Has made even my funky vtols' flyable and playable....

thanks.

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Is the new version (TCA v2.2.1)compatible with 1.0 as well.. or ONLY 1.0.2?

I never tested as I upgraded from 0.90 directly to 1.0.2, but you may try. I doubt they changed a lot (or even anything) in the API in two revisions. The KSP-AVC may be complaining if you have it installed, but you may fix by changing the KSP_VERSION_MIN in GameData/Hangar/Hangar.version file.

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Thank you for updating this so quickly! I've been very excited to use this, but didn't find it until just before 1.0 dropped so I haven't had a chance yet. So many things are possible with this, can't wait.

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In my experience TCA performs not very well with engines that introduces a death time to the control loop (which of course is very challenging). This applies especially to the most air breathing engines e.g. Quiztech VTOL engines. If you want to build a VTOL with (unbalanced) air breathing engines you have to write your own hover script http://ksp-kos.github.io/KOS_DOC/tutorials/pidloops.html or use some additional engines with much better control response time (usually rocket engines).

So you may try the following: Set your Quiztech engines to “manual control†and add some Rockomax 24-77 Twitch engines at front and rear of your vessel and declare them as “maneuver engines†with a little bit of tweaking this will do the trick. :wink:

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i have no idea of how to script and adding rocket fuel would make the plane too heavy

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Assuming a nearly balanced vessel you will need only a very little amount of oxidizer for the maneuver engines. I do not think that it will make your plane too heavy. But I understand your objection; “add more engines†may not have been the answer you’re looking for.

But you have to take in account that you’re asking for a very tough problem (even for real world engineers). Due to the inertia of jet engines (approx. 2-3 seconds) your plane will flip before any control input takes effect. Typically, you require a full features PID control loop with parameters adjusted to the specific needs of your vessel.

Eventually, TCA may give you access to that control loop parameters. Currently it provides access to P and I only. (I don't know if this is possible, I am not familiar with the internal algorithms of TCA)

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I'm not sure I understand your proposal. Could you post a picture or a .craft file of the vessel in question and describe which engines you want to control differently and how in particular?
I think what he means is two separate sets of engines and throttles: one set for vertical lift and one set for forward propulsion. By having independent throttles he can maintain his altitude with the lift engines and increase or decrease his speed with the other engines. For instance I have a large helicopter with four main rotors for lift controlled by TCA and two jet engines for propulsion which are manually controlled. To be honest though I just use Davon TCS for the independent throttles. I agree with his issues with it but it works fine with TCA so there's no real reason I think, to duplicate its features.

Unless of course it doesn't get updated for 1.0.

Thank you Adyx this is indeed what I mean, but when I use Davon TCS, it seems to override TCA in that my craft flips over rather than be smartly controlled as it would be if TCA was in charge. Perhaps I am doing it wrong, but there doesn't seem to be a tutorial on using them together :)

So basically you propose the same mechanism that exists now with the MainThrottle that controls vertical speed, but instead of the MT you want to use Pitch value. If I have understood you correctly, that's pretty easy to implement.

That sounds right, it would be a nice option to have if you find the time or want to implement it.

I gave some more thought to this idea and see only one, but serious issue: KSP does not allow you to switch vessels while flying in the atmosphere. So even with multiple TCA instances you simply cannot switch from your hovering carrier to another vessel.

I see, do what you think you must do.

thank you for taking the time to read my lengthy proposal

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Is there any way to prevent the engines from "helping" with maneouvers?

I used a similar mod some time ago (can't remember the name) that had the same issues.

Craft is very steady even if engines are not balanced around center of mass, however as soon as you touch the controls the engines try to "help" you with the maneuver, resulting in a craft that is EXTREMELY twitchy.

I tried fiddling with Pitch/yaw/etc controls in the MOD but, as with the other mod i tried long ago, if i lower the values enough so that the engines don't "help" as much, they are also not able to keep the craft steady when NOT touching the controls.

Is there a way i can simply set the engines to always go exactly through the center of mass, but not fiddle with anything else?

If i'm correct, in that way each engine should have a set percentage of thrust that never should change (except when fuel is consumed or mass shifts)

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Hello.

I have a smal bug to report. I have a small problem with your mod while using endurence mod. What sadden me is that it was working just fine in 0.90. It was very usefull, specialy for the Lander, I could accuratly balance the lift engine when taking off, and cary heavy weight under it as well (I have hidden some engine at the bottom of rear leg). Since the last update, I cannot use the main engine of the lander and Ranger ( the one incorporated into the Command pod) Unless its set to "manual control".

Would you mind taking a look?

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Would you mind taking a look?

I'm new to this mod myself, but I'm betting more details will be required for useful troubleshooting. Pic of the ship (ideally, showing the engines), configuration of all the engines, configuration of the mod... these come to mind, just for starters.

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I'm new to this mod myself, but I'm betting more details will be required for useful troubleshooting. Pic of the ship (ideally, showing the engines), configuration of all the engines, configuration of the mod... these come to mind, just for starters.

Humm, I don't think picture would help. But I could clarify my problem! The problem seem to occur when the engine is the command pod itself or maybe the root part. Basicly the engine is trust limiter fall to zero when I activate TCA. The issue only occur with the Lander and the Ranger form Endurance mod. Again, as far as I know they are the only one to have engine built in the command pod...

When I will be back home, I will do a quick test, I will test the lander as a non Root part. I will then be eable to say if the bug is related to having engine as root. If its the case, I guess it will be a good place to start. I might be eable to come with a work around that don't involve fixing this awesome mod.

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I can confirm the bug is related to having the Engine as the root part.

Edit: In fact, its not that, If I switch control wiht "command form here " to a docking port, then it work.

Edited by RedParadize

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Quiztech aero pack engines freak out when i raise the altitude with tca
In my experience TCA performs not very well with engines that introduces a death time to the control loop (which of course is very challenging). This applies especially to the most air breathing engines e.g. Quiztech VTOL engines. If you want to build a VTOL with (unbalanced) air breathing engines you have to write your own hover script http://ksp-kos.github.io/KOS_DOC/tutorials/pidloops.html or use some additional engines with much better control response time (usually rocket engines).

So you may try the following: Set your Quiztech engines to “manual control†and add some Rockomax 24-77 Twitch engines at front and rear of your vessel and declare them as “maneuver engines†with a little bit of tweaking this will do the trick. :wink:

i have no idea of how to script and adding rocket fuel would make the plane too heavy
Assuming a nearly balanced vessel you will need only a very little amount of oxidizer for the maneuver engines. I do not think that it will make your plane too heavy. But I understand your objection; “add more engines†may not have been the answer you’re looking for.

But you have to take in account that you’re asking for a very tough problem (even for real world engineers). Due to the inertia of jet engines (approx. 2-3 seconds) your plane will flip before any control input takes effect. Typically, you require a full features PID control loop with parameters adjusted to the specific needs of your vessel.

Eventually, TCA may give you access to that control loop parameters. Currently it provides access to P and I only. (I don't know if this is possible, I am not familiar with the internal algorithms of TCA)

Thank you, Kablooey, your explanations are perfectly correct.

To "clarify" things a bit: TCA exposes only the P and I coefficients because it actually uses a PI controller (without the differential component) as a band-frequency filter for engine's thrust limiter to prevent tremor and oscillations. And the values of the limiters are computed by optimization of the objective function F=|total_toque - needed_torque|

So sensitivity of the control response should be tuned via the main Steering Gain or the separate yaw-pitch-roll gains.

- - - Updated - - -

Is there any way to prevent the engines from "helping" with maneouvers?

I used a similar mod some time ago (can't remember the name) that had the same issues.

Craft is very steady even if engines are not balanced around center of mass, however as soon as you touch the controls the engines try to "help" you with the maneuver, resulting in a craft that is EXTREMELY twitchy.

I tried fiddling with Pitch/yaw/etc controls in the MOD but, as with the other mod i tried long ago, if i lower the values enough so that the engines don't "help" as much, they are also not able to keep the craft steady when NOT touching the controls.

Is there a way i can simply set the engines to always go exactly through the center of mass, but not fiddle with anything else?

If i'm correct, in that way each engine should have a set percentage of thrust that never should change (except when fuel is consumed or mass shifts)

Currently there's no way, except to switch them into the manual mode; but that's not what you want I suppose)

Apparently, we need a fourth engine mode in TCA: Balance Only -- group of engines that is optimized to always provide zero torque. That's not easy with the current calculation scheme, but I have the general idea of how to do it.

What is strange, is that when you lower the steering gains your craft looses steadiness. These controls only affect the steering, not the balancing. Then again, without some steering help from the SAS a balanced craft experience negligible torque, but it still may have a non-zero angular velocity.

- - - Updated - - -

Thank you Adyx this is indeed what I mean, but when I use Davon TCS, it seems to override TCA in that my craft flips over rather than be smartly controlled as it would be if TCA was in charge. Perhaps I am doing it wrong, but there doesn't seem to be a tutorial on using them together :)

Now I see. That is indeed a useful option. Do you have an idea of how this should be implemented in terms of user interface? I mean, we only have one Main Throttle. Of course, if I add the Pitch->altitude control, we may use the MT for the linear thrusters group, but if a user wants to use MT for altitude, then what? Add a separate slider and control this groups' thrust with a mouse?

- - - Updated - - -

Hello.

I have a smal bug to report. I have a small problem with your mod while using endurence mod. What sadden me is that it was working just fine in 0.90. It was very usefull, specialy for the Lander, I could accuratly balance the lift engine when taking off, and cary heavy weight under it as well (I have hidden some engine at the bottom of rear leg). Since the last update, I cannot use the main engine of the lander and Ranger ( the one incorporated into the Command pod) Unless its set to "manual control".

Would you mind taking a look?

I'm new to this mod myself, but I'm betting more details will be required for useful troubleshooting. Pic of the ship (ideally, showing the engines), configuration of all the engines, configuration of the mod... these come to mind, just for starters.
Humm, I don't think picture would help. But I could clarify my problem! The problem seem to occur when the engine is the command pod itself or maybe the root part. Basicly the engine is trust limiter fall to zero when I activate TCA. The issue only occur with the Lander and the Ranger form Endurance mod. Again, as far as I know they are the only one to have engine built in the command pod...

When I will be back home, I will do a quick test, I will test the lander as a non Root part. I will then be eable to say if the bug is related to having engine as root. If its the case, I guess it will be a good place to start. I might be eable to come with a work around that don't involve fixing this awesome mod.

I can confirm the bug is related to having the Engine as the root part.

Edit: In fact, its not that, If I switch control wiht "command form here " to a docking port, then it work.

Thank you for the report. I see the problem and will work on a fix. It is strange, though, that it was working in 0.90, because I haven't changed calculations even a bit in the 1.0.2 compatibility release. So the problem is in some obscure KSP-API changes that I missed.

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Greetings.

I need help.

In editor or in flight (through the part menu) you may set any engine to work in one of the three modes:

  1. Main Engine (default). TCA tries to maximize the thrust of these engines. In a perfectly balanced ship all Main Engines should have 100% thrust in the absence of control input. These engines are also used to control vertical speed.
  2. Maneuver Engine. TCA tries to minimize the thrust of these engines. In a perfectly balanced ship these engines produce thrust only in response to control input
  3. Manual Control. TCA does not change the thrust of these engines, but includes them in calculations.

I can't change engine modes not in flight nor in editor. :(

When I rightclick on detail there is no such option at all. :(

But TCA works fine and all engines work as 'Main' as I can see.

Version 1.0.2, TCA 2.2.1 is the only plugin installed.

What could be gone wrong? (sorry for my english, btw :) )

Edited by demol

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This thing gets rave reviews, but so far no matter how I play with the sliders even the most basic 4 poster craft riding rockets offering near instantaneous throttle response leaves the craft wobbling like a quarter nearing the end of its spin on a table. I can get it to stop while not using Kill Horizontal Velocity and turning off any steering authority, but this basically guts functionality. Even adding little rockets to maneuvering groups leaves the mains trying to do the steering themselves meaning the problem still rears it's ugly head.

Edit: Also this thing seems to be killing SAS as soon as I enable it. Is this normal behavior?

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