#Clockwork / Create: Propulsion — How to calculate balloon lift vs ship mass for stable airship hover

1 messages · Page 1 of 1 (latest)

lunar plover
#

Hi. I’m trying to build an airship in Clockwork / Valkyrien Skies / Create: Propulsion and I’m struggling to understand how to properly balance hot air balloons and vertical propellers.

My goal is:

balloons should carry most of the ship’s weight
vertical propellers should be used only for controlled ascent/descent
the ship should be able to hold altitude smoothly without bouncing

The problem is that hot air balloons need active heating / steam input, so when I reduce or cut the input, the ship starts descending. Because of that, I can’t figure out how to find the correct balance point.
**
What I want to know is:**

Is there any actual formula or known calculation for:
balloon volume / count
ship mass / solid block count
required hot air input / RPM
lift needed for neutral buoyancy
Is there a way to determine:
how many balloons are needed for a ship of a given mass
how much lift should be left for vertical propellers to handle up/down movement
What is the recommended setup for a stable dirigible-style airship:
balloons provide ~80–95% of lift
propellers handle the rest
minimal oscillation in altitude

Right now I’m basically trying to find the “neutral hover point”, but because balloon lift depends on active input, I don’t know whether I should balance around:

no input
low constant RPM
or some other target value

If anyone knows the actual mechanics, internal formula, or even a good rule of thumb, I’d really appreciate it.

onyx pebbleBOT
hot loom
#

🙏🏻

hushed junco
#

the atmosphere is thinner up higher, so you can’t remain neutrally buoyant if you use propellers to go up and down

sharp wolf
#

also propulsion balloon uses a PID internally

#

so its math isn't very easy to predict

lunar plover
#

So if neutral buoyancy changes with altitude, and propulsion balloons already use an internal PID, then a simple fixed formula probably isn’t realistic.
In that case, what is the recommended practical design for a stable dirigible-style ship?

sharp wolf
#

computer craft

#

aka CC: Tweaked

lunar plover
# sharp wolf are you willing to use CC

Yes, I already have CC: Tweaked in the modpack, so I can use it.
If it helps maintain altitude smoothly without oscillating up and down, I’m absolutely fine with that.

sharp wolf
#

the solution

#

is to slap yet another PID ontop of the problem clueless

#

you can setup a PID relatively easily with CC:VS (it has some built in PID functions for you to use)

#

then just hook it up to propeller strength and maybe balloon strength

#

mess about with the P I and D values until it works as you want

lunar plover