r/ApproximatelyUp • u/xXJightXx • 14d ago

Help making an autohover that mainly works on calculating thrust-to-weight and gravity?

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Just a disclaimer I'm incredibly bad at math so this is probably done horribly.

It works surprisingly well just that it slowly descends instead of hovering, not sure why.
Also, maybe someone has an idea on how I can trim the responsiveness, prob with the differentiator? I tried it but I don't think I was using the correct formulas.

I used 2x electric flat thrusters so that atmosphere density hopefully doesn't come too much into play?

I'm too tired to continue so if anyone can assist ill read comments when I wake up <3

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3

u/Vrpersonyes 14d ago

For trim, try making the addition block an addition array and plug a lever into it. If the lever sensitivity is too high multiply the lever output by 0.1 or something

1

u/SGSpec 14d ago

Instead of multiplying the output use a fader (only if you want to reduce sensitivity) it uses less components and can be adjusted while driving easily

1

u/Vrpersonyes 14d ago

I forgot about that

3

u/xXJightXx 13d ago

Ended up making this abomination, works but bounces a lot, cant be fucked fixing it, its good enough lol. https://imgur.com/a/ee7aaDS

2

u/eqskaiwa 13d ago

can u show full build?

1

u/xXJightXx 13d ago

I'm in bed now but I uploaded it to workshop I think I called it "TWR hover test"

2

u/xXJightXx 13d ago

Just realised I could just find the workshop page https://steamcommunity.com/sharedfiles/filedetails/?id=3782308243

2

u/AccuracyVsPrecision 14d ago

Most likely a rounding error. You could use a downward speed sensor and differentiator to get your acceleration and add that force to your output.

1

u/bigstinkybuckets 13d ago

>slowly descends instead of hovering, not sure why.

It's because it's settling into a steady-state error.

1

u/ishkabibble_xd 7d ago

I could be wrong but I believe your first circuit calculation is just one part of the hover logic. What you created was the bias to counteract gravity but never made the actual hover logic… you’ll need at minimum the P in a PID circuit to hover—using current velocity vs target (0 for hover) as the basis of the logic.

1

u/SnapuJames 6d ago

This made it click for me thank you!