Elliptic orbit [UPDATED]

[KnutsoPX]

Hello all,

Just wondering the best way to achieve an elliptic orbit around an object. I'm not necessarily worried about the revolving object speeding up as it gets closer to the central object, I just need a smooth elliptic motion.

My best guess was to use a set of pistons on the x and y axis. If anyone else has any thoughts, please let me know. Thanks!

[Dav1d0]

either pistons or sequenced movers

[comphermc]

My best guess was to use a set of pistons on the x and y axis. If anyone else has any thoughts, please let me know. Thanks!

Do this. Then put a tag on the elliptically moving part and have the object follow it around the path. Choosing the right materials to get the strengths correct is important, and this worked for me:



You can of course use hologram instead of sticker panel. You also need to make sure that the two pistons have the same timing setting, but offset one of them by 25% of the total time. For example if they are both set to 4.0 seconds, I set one of the piston's sync setting to 1.0 seconds. Similarly, if the timing of each is 3.2 seconds, one of the syncs will need to be 0.8 seconds. Of course it doesn't have to be perfectly at 25%, but then you will get elongation in one direction and the ellipse will appear tilted.

This is what my path looked like:



To make sure you don't see the stone mounts in the scene, you can make the longer piston have really high min and max distance settings (so the mounts are way off-screen).

[GribbleGrunger]

yes, i've tried this myself. i was trying to get a figure of eight though and i couldn't seem to get the exact balance between one going in and out once while the other does it twice. is it possible to do a figure of eight ?... and if so more too?

edit: lol, i'm just thinking, i may well have forgotten to use the sync when i tried it

[comphermc]

is it possible to do a figure of eight ?... and if so more too?

edit: lol, i'm just thinking, i may well have forgotten to use the sync when i tried it

Yep. You forgot to sync, which is now 1/8 the duration instead of 1/4 the duration.¹ Timings on mine are 1.6 seconds and 3.2 seconds, with a sync of 0.4 seconds on the longer:



¹ Or odd multiples thereof.

Edit: Bonus points to whoever can make a piece of candy:



And instant high score for this beauty:



Edit2: Okay last one. Sorry for hijacking this, I was just too intrigued in it all. Hooray math!

[KnutsoPX]

Thanks comph! That looks like it should work perfectly.

UPDATE: Just out of curiosity, how would one go about adding the correct gravitational pull to something like this (have the revolving object speed up slightly as it moves closer to the central object)?

Also, @comphermc, is there a reason sticker panel will not work for the anchor piece in your picture? What material is that you used?

[comphermc]

UPDATE: Just out of curiosity, how would one go about adding the correct gravitational pull to something like this (have the revolving object speed up slightly as it moves closer to the central object)?

Also, @comphermc, is there a reason sticker panel will not work for the anchor piece in your picture? What material is that you used?

I don't know about the gravitational pull, tbh. There are a myriad of ways you could fake it, but I'm not sure it will be convincing.

I used basic stone for my mounts. The one with the tweaker on could have been anything, but it was important that the weight ratio from the middle piece to the end piece be as high as possible, since connectors lose strength in series and are tied to the weight of the object.

[KnutsoPX]

Thanks again!

[GribbleGrunger]

you know when you ask a simple question and then someone just has to show off........

and what about a perfect circle? i assume that would be setting both to the same values? and is the invisible material on the Vita sturdy enough to support this method? the reason i was trying to do the figure of eight was because i hade two platforms and i wanted a fireball to do a figure of eight around them. i never got it working (because i forgot sync... doh) so i never got round to solving another issue: clearly i can do what i wanted now, but is a fireball attached to a piston strong enough to hit sackboy and still continue on its course without faltering? i could make the fireball out of sticker panel, but what of other materials?

[comphermc]

and what about a perfect circle? i assume that would be setting both to the same values?

That, or just use a rotator with the tag on the edge of the material.

[...] clearly i can do what i wanted now, but is a fireball attached to a piston strong enough to hit sackboy and still continue on its course without faltering? i could make the fireball out of sticker panel, but what of other materials?

You forgot that the tag is meant to be used as a way to have an object follow the path, which is irrespective of the weight.

[GribbleGrunger]

That, or just use a rotator with the tag on the edge of the material.



You forgot that the tag is meant to be used as a way to have an object follow the path, which is irrespective of the weight.

ah yes of course, so it wouldn't effect the piston at all.

[Aya042]

I used basic stone for my mounts. The one with the tweaker on could have been anything...

What's wrong with using DM/LM instead of a tweaker?

[comphermc]

What's wrong with using DM/LM instead of a tweaker?

Nothing at all.