#AR-100 Harpoon

1 messages · Page 1 of 1 (latest)

empty frost
#

But what if instead of rigid manipulators. Or articulated ones. We literally have that magnet which drags targets. A means of launch, possibly a pneumatic cylinder and a good old winch?

Features:

  • High-stress hardpoints only!
  • Pneumatic launch cylinder (Possibly tunable for different launch speeds)
  • High power superconductive electromagnet and a grabber-claw (The same kind that is on the AR-1500)
  • A length of high stress cable (Tunable? 200 meters sounds about right)
  • 360 degree free rotating block to allow winched object to be at any orientation towards your craft

Operation mode:

  1. Fire it like a coilgun by pressing spacebar with device activated
  2. It automatically latches onto the closest object that is not your craft, just like AR-1500, and possibly imparts kinetic energy to it, because the magnet is not weightless
  3. Winch it towards your ship by opening the cargo bay excavator! (Tunable winch speed! Less motor speed equals more torque)
  4. If you have latched onto the undesired object, it can be released by deactivating the device, which will deactivate the claw and automatically winch it back into the launch position.
  5. Once fully retracted, winch sits in the launch cylincer, roughly at the excavator level, maybe a bit further. Launch cylinder has the same semi-rigid dampening structure as current AR-1500 mount.

Possible implementation issues:

  • There is nothing so far in this game which would act like a cable. Collision with other objects, or no collision.

Possible user issues:

  • No control over the grappled object. Or, rather, only one control - either winching it towards you or not. And in space there's inertia which potentially could result in an ungodly quantities of spinning.

Image (Just some british space harpoon nonsense, but it's illustrating the purpose pretty well!)

4A3A633E00000578-0-image-a-2_1521191286498.png
frank junco
#

We've had tether, harpoon, winch, etc suggestions a lot - including my own. The typical objections that make them currently implausible is that they need to be implemented with correct physics to not look obviously gamey (like crossing objects they would wrap, even while pulling a harpooned object against it), and correct physics for wiggly things means a heavy computational cost.

empty frost
#

The wrapping issue could be resolved by it automatically picking up the slack, making it always taut. But you are right, for any kind of "rope" that is a physical object, physics would be a mess

frank junco
#

That's a common suggestion, but it kind of NEEDS to wrap, because if you just draw a line, it's possible to pull one object against a massive iceroid, while the straight, taut cable lays on top of the iceroid, but not pulling the object around it.

empty frost
#

Passing through the small iceroids without an issue, but snapping when encountering the ones large enough to "touch" it (Imagining it's rather high mounted on the ship, on a small boom)

#

Or alternatively the collision model of a cable could be made like a bead chain. Say... 10 meter collision "beads" every 20 meters? that still sounds like a lot. But would allow it to wrap and slide agaisnt larger objects and wrap around smaller ones

frank junco
#

I think that's the main problem; lots of physics objects all needing to judge tension, break conditions, check collisions, etc.

next orbit
#

I think one option to avoid having to do physics, or at least allowing faking some of it, would be a tethered manipulator drone.

Basically a claw with it's own RCS block on a hose+cable.
It wouldn't use tension to reel things in so handling collisions wouldn't be important.

frank junco
#

Essentially what our drones are; just that the cable is a laser.

next orbit
empty frost
#

Or rather, vaporising

#

Not generally something you wanna do to the piece of salvage

next orbit
#

Yeah but RCS block on a hose can have as much propellant as you do.

dire badge
empty frost
frank junco
#

You have as much RCS as you have drones, because they're 90% RCS propellant.

empty frost
#

Hmmm. A special drone mount that allows them to lug heavy objects?

frank junco
#

I think a low-stress salvage mount runs into issues that are less practical, and more balance- and intent-based.

next orbit
#

TBH I don't think this would work as standalone salvage option as it would be unable to brace the target for boosting, but it would be able to move even larger stuff, would be low-stress capable and would only cost maintenance and propellant.

frank junco
#

How would you use the ability to move ice or ships?

next orbit
#

Not sure, but being able to bring a ship to a desired position without blasting it with your RCS might be helpful.

frank junco
#

So, maybe, abstract it as a spline crossing some points, with the points anchoring the spline having an impulse to straighten like a hinge. Abstracted, you can use fewer points than a simulated rope. Detect collisions by firing a ray along the path of that spline, and just disconnect entirely upon any collision, to immediately null any weirdness about disparities in the plane of the object tethered and the plane of the cable crossing over large objects. Also, avoid having to simulate a rope's physics in response to collisions.

In lore, you can treat it as a tube that is pressurized from the source (your ship) after impact to make it straighten out, bringing ore in front of your ship as it retracts. Contact sensors to avoid abrasions that would damage the cable. You can allow crossing over fellow chunks, which are small enough to bump while the cable passes over, but break it when crossing any large object, like a ship or ice chunk.

Not an ideal solution, maybe, and perhaps a ton of tweaking and tuning and math to make it look decent, probably more work than it's worth and definitely not pre-1.0. But worth suggesting, just in case.

image.png
next orbit
frank junco
#

I'm not sure what that means, but if you mean using RCS to arc over the plane of the rings and back down to the target like a tentacle, I'm not sure there's any possible way to make that look natural or normal.

#

The normal way to do it just using the abstraction would still look weird, and if you tried to bend and warp it to make it LOOK like it were arcing over you'd still have to detect where it would collide to make it pretend that it isn't.

#

I also just don't think I can understand how to make it look right without just feeling weird.

next orbit
#

I mean RCS could be in plane, but hose could go above stuff without raising too many questions.

#

You'd still need to make the hose loopy-shwoopy in convincing ways, but it wouldn't need to catch on stuff and would never be used to reel the whole package in.

#

So the hose itself would be purely cosmetic.

frank junco
#

Yes, that's what I think looks weird. Having a chunk bonk against a massive iceroid over and over that isn't distorting itself to move out of the way would look weird, and having an articulated tentacle-rope that knows where it would collide and needs to distort comes back to many physics objects with collisions AND looking weird.

#

Having it just completely loose would, I think, require some active articulation, because that's just what a garden hose does when you turn on the water, it straightens.

empty frost
#

Huh. I was thinking of something like this

And if it can't pass through ringoids, well. Why should it? Our ships can't "Hop over" or "dive under" obstacles as well. Would make a good 2D simplification

Harpoon.png
#

Then we also get rid of the bonking issue.

#

And if something gets caught in the rope, there are 2 options both of which are realistic:

  • Either rope breaks and you need to retrieve your critical piece of equipment.
  • Or it wildly catapults whatever you were trying to harpoon away

Could be both

empty frost
# frank junco How would you use the ability to move ice or ships?

Returning to this one

Considering that initial proposition was to have an arm on a bit of a standoff before the ship, it would be useful for salvage ops. Capturing object, retracting cable fully and having it sit on that high stress brace, firmly locked agaisnt the ship, would allow for heavy object recovery

What I would use it for:

  • Capturing high value or high speed ore that may be obscured from getting to it manually by ice.
  • Forcibly stopping ships and capturing debris and salvage from safe distance such as Containers, Orbs (both) et cetera.
  • Dragging ice chunks towards your ship and preventing them from moving away after cracking large ringoids
  • Tarzan-like swinging around remote ringoids. In a controllable manner, not like AR-1500 that will turn you around by itself at the worst moment.
frank junco
#

Every section is a separate physics object, each independently checking conditions, stress, failure conditions, interactions with each other. Physics is our bottleneck for a lot of players.

empty frost
#

Then I guess automatic grapple disengage on cable contact with obstruction would be the way. Accurate too - to prevent loss of equipment, when cable is touched by ringoids, it automatically releases the target and retracts at max speed. Then we only have to deal with 1 physical object being the "claw" that we toss

frank junco
#

No idea if it's feasible; collision detection along a spline not not be possible without modeling a collision . . . volume? I don't know enough about coding or Godot to be sure.

empty frost
#

Right, but then we don't have to deal with what, 10-20 extra physical objects with mass and rigidity and et cetera, just a "hitscan" zone around the cable

#

Plus your idea that it inflates with steam is actually pretty darn good - would explain why it keeps straight

frank junco
#

And why it must disengage rather than abrade. My HOPE is that you can use a raycast or something along the path of the spline - fire a beam that follows that path.

#

Use a spline, it doesn't HAVE to be straight, even though it would tend to straighten.

mild dragon
#

just saying