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Gimbaling the Direction Indicator


corona_wind

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The uses of these things are severely hampered by their fixed internal reference points and how awkward they are to rotate physically.  If they possessed a "gimbal" to rotate the inner reference point on keypress and a way to configure that in the editor, we could do so much more.

Look at this drone, the Axe X:

Nimbatus_Axe-X.png

That funny "tail" which rotates a direction indicator on a joint?  That's a gimbal built the hard way.  It has so many uses it ends up everywhere on my designs despite how awkward, wobbly, huge, and fragile it is.  I've used it for:

  • Following walls very reliably.  I completed all racetracks to the top 50 100 just following walls, until I realized 'next waypoint' was an option!  Doh.
  • Holding unbalanced drones on a straight line course.
  • Catching and correcting overshoot for very fast turns without oscillation.
  • A drift compensator to "lean into" curves on racetracks
  • Tracking the size of the sumo ring
  • Making sub-drones orbit the main drone at a distance.
  • [edit] Angular accelerometers
  • [edit] Tracking your drone's location on a planet

They're really awkward to use in other ways.  Observe the pair of 'eye's in that drone.  I needed two since I didn't have room to rotate one at 45 degrees.

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Would mind throwing together a couple -simple- examples of a crude gimbal in action. Ideally with an actual drone file to poke at either uploading here or to Steam.

I think I'm starting to see the usefulness of what you're asking for, but the presentation is still going mostly over my head. I doubt I'm alone in that respect.

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"A device that keeps something horizontal", my translator says as a succinct description; and then, when asked about such thing (un cardan), my unilingual dictionary shows me a picture that looks like anything but a gimbal, and is described as anything but a gimbal. Just the moment I though I had pictured it right, too.

Would a gimbal perhaps look like the device that is keeping these pink lights pointed up, and yellow lights pointed down? A directional sensor mounted on a motorised hinge.

769491814_Pinkisup.gif.61b84542793bba787bbbe062fcd9171c.gif

If so, such a contraption is handy to keep track of a direction, and to care little about the North Star when pressing movement keys. Here, pressing "go left" will make the craft go left, no matter its angle and position.

1500130558_Leftisleft.gif.1c01805e3e9e2ec402e2b8375390f3ec.gif

Some humble examples, if they may help.

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Gimbal just means a frame for something to spin in.  Ookami-sama has it exactly right -- my idea is nothing but a direction indicator which spins on keypress and in the UI.  The most obvious use:

Fixed Rotation

Sometimes you just need a tilted indicator.  Hex, you showed me your Wraith rebuild.

Parallax Racer Control.jpg

Wouldn't it be less awkward if you could punch -11 degrees into the UI?  No more bouncy eyestalks, no more dead-zone tricks.

That's the tip of the iceberg.  If the angle can change during flight, that opens up so many options it's hard to list them all.  I'll make a better showcase of the uses I've discovered so far once I'm home and can screenshot, etc.

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OK, so what I'm talking about is a new kind of feedback loop.  Rotating a position indicator on command lets it act as several new kinds of sensors:

  • Compass / Heading
  • Angular Velocity
  • Angle

...as well as several other things I don't know how to describe yet.  And probably more I haven't thought of.  It's all in how you wire it.  But it's a really cumbersome, slow, huge, wobbly part right now.  Adding this talent to the basic directional indicator would be like adding five new parts to the game, not to mention, letting us use the same old part in ways it was awkward to do before, like at 45 degrees.

Examples, examples.  Click images for .DRN files.

Gimbal%20Example%201.png

Something like this was one of my first designs.  It's not the best thing ever, but you get the idea:  The heading is controlled by rotating the gravity direction indicator.  It acts like a compass.  Knock it off course and it will turn back.

Gimbal%20Example%202.png

Here's a better example:  I built the wobbliest racer I could and added a stabilizer.   The waypoint direction indicator on right controls the outer pair of engines in traditional fashion.  The gravity direction indicator on left controls its own axle to keep itself pointed down.  Put another way, it measures how fast your drone is turning, somewhat proportionally even - turn faster and you get longer pulses.  This signal controls the inner pair of engines, damping the wobbles.

Gimbal%20Example%203.png

And here's the craziest thing I've done with the idea:  Proportional steering!  The direction indicator is rigged to turn itself (not the craft -- it turns itself) towards the waypoint.  The engine booms are turned by the same signal.  So the direction indicator ends up measuring the exact angle between the craft and the waypoint, and pivots the engines a proportional angle, magnified a little to compensate for drift.

Fww2HwJ.gif

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Hadn't thought of that. Tried it out and it works great in small scale; very tight cornering. I can't scale it though. The motor hinge breaks off with too many afterburners. I managed to squeeze in 5 of them before everything wobbles the hell apart. I tried running 2 hinges per side to distribute the load but you can't rotate things seamlessly with 2 centers.

Have you managed to scale it? @corona_wind

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It's still the best I've done so far.  I keep hitting walls, literally and figuratively, trying to improve it, which is one of the things motivating me to post this topic.  If the indicator-on-a-stick was a dedicated part instead of a kludge, it would work a lot better.

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You're certainly not alone in wanting this sort of thing.  I tried building sub-drones that would orbit the main one, and the size they have to be to make that work gets silly!

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What I imagine is a direction indicator with a configuration slider that allows this to happen:

45-dir.png

...plus inputs like a motorized hinge, to change that setting in-flight.

It's important that it shouldn't physically rotate itself or anything attached to it.  It's the one part in this game which really needs to be stable.  All that's really changing is its frame of reference.

Moving the reference gives the basic direction indicator more uses than i can properly explain.  There's just too many, and I keep finding more.

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I get around this issue altogether by using VTOL thrusters on free hinges: Small, only 1 extra block (assuming it has fuel, up to 3 if not) and just better than using a 200-speed motorized hinge. You can even flip it at will, too.

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