[WIP] Infernal Robotics Robotic Arms

[Guest]

Hmm, if it occurred only in precision (low speed) mode and was insubstantial, it could indeed improve on the wobble problem.

BTW, how's it going? I'm re-releasing the CSS, and I feel uneasy about sending people to Romfarer's plugin, which has not been updated. I will remove the arm from the .craft file, but I'd love to migrate it to an IR-based implementation.

[sirkut]

The only issue now is attaching the arm to objects. Once that is done it is complete. Everything else works. Movements and the camera is all working.

[Taki117]

The only issue now is attaching the arm to objects. Once that is done it is complete. Everything else works. Movements and the camera is all working.

Why couldn't you use a KAS magnet module, or a Klaw module in the config? (I don't know if that's possible)

[artwhaley]

I'm assuming it doesn't work to just put an attachment type node at the end of the arm, and let the user worry about whether they want to throw a magnet or a claw or a docking port onto it?

[lo-fi]

The problem is the way KSP creates joints. It doesn't create a joint between the root of the part you're placing and the component of the part you placed it on, it creates a joint between the part you're placing and the rigidbody of the part you're placing on, which will be applied to its root. This is why things that get mounted to animated components stay fixed in place when what they're visually mounted 'on' moves around (and why mounting to cargo bays doors is prohibited).

I'm sure you've probably got a plan, Sirkut, but I've been quietly researching this too. I've got some fresh ideas after ploughing through piles of unity docs, but have yet to try again. I'll let you know if I come up with anything useful

[artwhaley]

I was just wondering about a node as this is how the basic IR plug in works. I wonder... could you move the arm the way you currently are each frame, then calculate the distance and rotation between the base and end of the arm, then move the end node to that point by the same mechanism as IR? The end point wouldn't actually be attached to the animated arm. .. it would just always be colocated with it.

I'm just theorizing. .. I haven't looked at the IR code to see how it works.

[sirkut]

lo-fi. if you discover anything I'm all ears.

The way that this robotic arms (RA) plugin works is completely different than how the IR plugin works. For IR, there consists of 2 separate meshes, each joined at the origin. By naming the mesh, a joint is then created between the two meshes allowing it to move. The way that RA works is the entire part and it's meshes are compiled into a descending hierarchy as noted in the OP. If I move the topmost mesh, the whole thing moves, etc and this is done by merely doing transform rotations (at the moment, I will do pistons eventually). By doing it this way I have to rethink how to do the joint for the endmost point of the robotic arm in order for this to work.

[lo-fi]

Will do, Sirkut. It's one of those things I hack at occasionally, but haven't quite nailed yet.

That's not a bad idea at all, artwhaley, I might have a go with that method too

[montyben101]

How did they do it in the lazer pack robot arms?

[Taki117]

How did they do it in the lazer pack robot arms?

They used the module for the KAS Magnet.

[sirkut]

They used the module for the KAS Magnet.

Wrong. That is not how the Lazor robotic arm pack does at all. Lazor creates a dummy gameobject based of of the tip's mesh and uses that to create a fixed_joint when attaching it to something.

[montyben101]

Wrong. That is not how the Lazor robotic arm pack does at all. Lazor creates a dummy gameobject based of of the tip's mesh and uses that to create a fixed_joint when attaching it to something.

But I'm guessing you can't use that then?

[sirkut]

But I'm guessing you can't use that then?

I can but I just haven't contacted romfarer and ask if it's kosher to do so.

[Jovzin]

So what is the status of this Robotic Arm ?

[sirkut]

Still working on it. I'm a busy person these days.

[Jovzin]

OK no problem. I had the busy work days for whole December. So I know...

[bigdad84]

Any new news?

[Jovzin]

Hello sirkut. So have you found the way how to create this magnet or grabbing node for your great robotic arm and plugin ?

It looks really great. Can't wait for it. I had some time to go through all 7 pages of this thread and the vidoes are great. And that Canada Arm with your plugin is a masterpiece. Can't wiat to see it in action in my game together with CSS.

Wish you all the best in new year

[sirkut]

Not yet and I've been extremely busy with work and outside tasks. The Canada arm was actually from the Lazor arm pack.

[lo-fi]

Morning Sirkut. I've been playing with configurable joints a lot lately, think I may have a workable solution to the end effector problem. Any chance I can get hold of the arm to try it out?

Also, if you have a few minutes, check out the KF thread for some trailer (and caravan) hitching joint shenanigans!

[ZodiusInfuser]

Morning Sirkut. I've been playing with configurable joints a lot lately, think I may have a workable solution to the end effector problem. Any chance I can get hold of the arm to try it out?

Also, if you have a few minutes, check out the KF thread for some trailer (and caravan) hitching joint shenanigans!

Don't you have enough on your plate already

[lo-fi]

Yes, but this is tempting, low hanging fruit

[sirkut]

Morning Sirkut. I've been playing with configurable joints a lot lately, think I may have a workable solution to the end effector problem. Any chance I can get hold of the arm to try it out?

Also, if you have a few minutes, check out the KF thread for some trailer (and caravan) hitching joint shenanigans!

Sure give me a few days to get my stuff packaged and sent to you. Code will be ugly until I have time to tidy it up. If you got a solution then this WIP can be close to release.

[lo-fi]

Cheers It's still an if at the moment, but while I've got all the joint stuff fresh in my head, now is the time to try! No worries about dirty code.

There would still be some issues to tackle like leaving something attached to the arm then moving out of physics range or changing vessel. I think KAS has a way to tackle this, and I potentially need to build something for the hitch, so might as well pool the knowledge.

[lo-fi]

Well, it does work:

Except because you have to use a non-kinematic rigidbody for the end effector GO that the joint gets created on, it produces no reaction force against the parts rigidbody and we're kinda breaking the laws of physics. This wasn't something I foresaw... Thoughts?