Gravity experiment

[Silent]

So I just did an experiment on gates of hell. Storage containers in the real world are 8.5 feet tall, there are some that are stacked 4 containers high in gates of hell, 34 feet. An object of 1Kg falling at the rate of 9.8m/s^2 from 34 feet should hit the ground in 1.45 seconds. I ran multiple tests of dropping the drone from 32 feet in the sim and got around 1.7 seconds on average. That puts gravity around 7.2m/s^2.

That is if the sim is to scale, just thought I'd send this, because I feel like the gravity is not right.

[Zunkey]

My results; using the average cargo containers hieght: 2.90m (9ft 6in)
Method: Lined the drone up as perfectly as I could using the Beginner flight mod (stablization, auto hover) in external (3rd person) camera. paused the game, started a timer on second monitor, recorded both screens as I dropped the drone by switching it to PRO mode, and unpausing.

the drop time took 0.87 seconds to drop the 1 container.


If a drone fell (1.018kg) 2.90m, it would have hit the ground in 0.76s
I however resulted in 0.87, and that was done by filming in slow motion.

My test is accurate within about 0.03s, so it cant be that far off.

Doing the math for if it was 7.2m/s spits out 0.89s in the calculator, so yeah. Id have to agree with this one.

[Zunkey]

seems like we also got something to complain about lol.


Good work devs, dont get down and all about all us complaining about the speed and gravity etc. the game overall feels great and getting dev responses in the forums is always great.

[76561198356906831]

Cool guys! Thanks for the experiments!

Using the game drone may not be a good approach to sample gravity as we have air resistance , minimal thrust acting and other combined behaviours.

Numerically on the engine we are using Earth's 9.8m/s²

On early runs we also distrusted the engine and made tests launching a sphere (with and without drag) to confirm the gravity was right.

We provided a StartVelocity and also StartHeight to it.
Then compared with hand written math.
The times were accurate for drag and dragless tests.

But I'll ping the team on your results!

Thanks!

[Zunkey]

Originally posted by costa-drl:

Cool guys! Thanks for the experiments!

Using the game drone may not be a good approach to sample gravity as we have air resistance , minimal thrust acting and other combined behaviours.

Numerically on the engine we are using Earth's 9.8m/s²

On early runs we also distrusted the engine and made tests launching a sphere (with and without drag) to confirm the gravity was right.

We provided a StartVelocity and also StartHeight to it.
Then compared with hand written math.
The times were accurate for drag and dragless tests.

But I'll ping the team on your results!

Thanks!

Drag would explain why. I just didn't know if DRL hsd it implemneted

[76561198356906831]

We surpassed the stock drag math the engine offers, taking account the drone body shape.

So, for instance, there are drag differences between falling nose-to-ground or bottom-to-ground.

[76561198356906831]

An extra note.
We asked the art team.
Containers on Gates of Hell are 3.5m :)

[Silent]

Honestly, I love how on it you guys are with communication with us.


Could you help me out with a few numbers?

-The area of the bottom of the drone.
-The area of the nose of the drone (side profile)
-The height of one container as it scales in the game
-Minimal thrust acting force in newtons (this is so that the motors are spinning at idle so you can still roll and yaw and such correct?)
-The drag coefficient of the drone you have in the game right now


I did another calculation using the drag coefficient of an object I deemed close to that of the drone. I got a fall time of 1.45 seconds in calculation, still far faster than my tests results showed. I feel like your drag coefficient is too high, but I would like to do more calculations.

I understand that there are other factors at play, it just feels like I'm flying on the moon, but maybe that is because I was so used to your old physics.

Maybe you could just send me a real racer3 and I'll be your beta tester and compare ;P

[Silent]

ahahahah 3.5 meters!! I stand corrected, no need to send me the details I just asked for. Calculating without air resistance puts my original experiment time to 1.68 seconds, factor in air resistance and it will probably be around 1.7 seconds. Your sim is working out well!

[Silent]

Thanks devs for working with us, It's nice to know more specific details about the game's mechanics. I'll say it again, y'all are killing it with the responses and the great work!

[76561198356906831]

Thanks IDGAF!
We are also cooking a blog post with a breakdown on our physics findings.
Should have a more in-depth log on what we have been doing to match IRL physics :)