VincentMcConnell
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Posts posted by VincentMcConnell
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you Never said it is to complex. But it is possible.
Not for a long while it\'s not. Stop posting about multiplayer in every single thread. It\'s annoying and you\'re not going to get multiplayer. So move on.
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Or you could just just subtract the dry mass by the full mass and you will get fuel mass?
You should be able to do all ALL rocket equations without doing a test fire.
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To find fuel in mass, simply divide liters by 200.
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Cool planet. How many will there be?
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Nova, why did you land with 256.6 meters per second?
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Currently Writing up a guide with Kosmo-Not on how to make interplanetary trajectory plans.
It will probably be ready in a few days.
It\'s actually easier than you\'d think to get to another planet, provided you have the math.
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Does anyone have a Delta-V calculator spreadsheet for Kerbal v0.16?
So you can plug in what parts you have in your stages and it works out the Delta-V.
Why would you need to do that?
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My experience is that there was a lot of trial and error on the learning curve in using the big parts. But now I can throw together a rocket with them and have it work without 'incident'.
It shouldn\'t be that way. We shouldn\'t end up doing all of the math to make sure the rocket has the fuel and power to get some where and then find out that the parts are poorly made and explode in random cases. This happened to me several times on a Mun Rocket during launch. The outboard boosters would jettison at the estimated time and then -- because the decouplers are weak -- crash into the TLI Stage, ruining it.
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I rather thing it\'s just every part...
The radial decouplers are also so weak, that mounted parts basically fall slowly off and crash into the below stages...
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I feel the desire to ask an obvious question: Why a zip file for such a simple vehicle? Why not just the .craft file?
Because drop box does .crafts really weird for me. When someone downloads them, all they get is a note pad with .craft info and I don\'t think anyone wants to compile their own .craft just to launch into orbit.
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Sounds like a guide I wrote up with a friend will help you here.
http://kerbalspaceprogram.com/forum/index.php?topic=17634.0
Wrote it just last night. lol. Now you can build your rockets to make sure they\'ll work.
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I watched an entire 15 minute video of stuff I know like the back of my hand. That\'s how you know you did a good job.
So, good job!
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Skipping those is a good way to get 500m over the surface of Mun before realizing that you didn\'t put a decoupler between your descent stage and lander.
Build checklist. =P Write up a list of all the important parts on your command stage and when you build a vehicle, check them off one by one. That will take practically no work compared to all the other stuff you\'ll be writing down while you build. Because of the things in this guide, I have only four rockets built in my stock KSP folder at the moment. But all of them work and they worked on the first try.
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You don\'t want to use Isp in the form of seconds for the rocket equation. You want to multiply it by G.
I\'ll fix it right now just to make it more clear.
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You don\'t have anything to directly tell you how far the planet is from you. I referred to my spreadsheet because there\'s a page on there that you can enter the orbital information and have it tell you the phase angle to do your burn at. Your burn point with respect to Kerbin should be directly opposite the sun. Just be sure Kerbin and the target planet are at the correct phase angle.
Yeah, the fact that it doesn\'t tell you how far away it is is kind of a problem.
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But how do you tell when you\'re at that angle in-game? I mean, 'Munrise' is a good way to measure 90 degrees, but there\'s no measuring tool in the game for arbitrary angles AFAIK (without mods)...
By distance. If you checked out Kosmo-not\'s spreadsheet, you\'d see that it judges by distance. So when the planet is a certain distance away from your orbit, you\'ll want to make the transfer. This brings the issue of launch windows and such, though. So going to other planets is really going to be a somewhat annoying thing.
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A Guide to Basic Kerbal Rocket Design:
By Vincent McConnell and Kosmo-not.
Introduction:
Getting to learn basic rocket science for a space game like Kerbal Space program can be very important to the success of building rockets that can perform a desired job. In this guide, we will be covering things like calculating the full Delta-V of your ship, explaining how to perform transfer maneuvers, getting Thrust to Weight Ratio, calculating the Peak G-force experienced during a particular burn, also calculating Delta-V needed for a full-Hohmann transfer and much more.
Delta-V (change in velocity) is the bread and butter of rocket science. It is probably the most important thing to know about your rocket because it determines what your rocket is capable of achieving. Among the several things we will explain in this basic tutorial, Delta-V is most likely the most useful thing you will apply to Kerbal Space Program while building a rocket.
To find the Delta-V of your rocket -- each stage at a time -- we have to sum up the part masses of every single part of the stage. When summing up fuel tank masses, it may be easier to write them like this on your paper:
Full Mass: x
Dry Mass: x
The reason for this is that it will be easier to calculate Full Mass and empty mass. So, simply sum up your entire stage mass.
The next important part of this set of calculations is to find your engine�s �Specific Impulse�. Specific Impulse is a measure of how fuel efficient an engine is (the greater the Specific Impulse, the more fuel efficient it is). In the case of the non-vectoring stock engine has an vacuum specific impulse of 370. So here, we must apply the Tsiolkovsky Rocket Equation. More informally known as �The Rocket Equation�.
It states: Delta-V = Isp*9.81*ln(m1/m2).
m1 = total mass of the stage
m2 = dry mass of the stage
So go ahead and sum up your stage�s full mass with fuel. Then, go ahead and sum up the mass MINUS the fuel mass. Input these into the equation in the place of m1 & m2. So, we will show a quick example, here:
Stage 3 (TMI, Mun lander, Return):
Full mass: 3.72
Dry mass: 1.72
Isp: 400 s
Delta-V: 3027.0 m/s
Stage 2 (Kerbin orbit insertion)
Full mass: 7.27
Dry mass: 5.27
Isp: 370 s
Delta-V: 1167.8 m/s
Stage 1 (Ascent):
Full mass: 38.52
Dry mass: 14.52
Isp: 350 s (estimated due to atmospheric flight)
Delta-V: 3349.9 m/s
Total Delta-V: 7544.6 m/s
Note:
To calculate the Isp for multiple engines with different Isp values, you need to take the weighted average of the specific impulses relative to thrust. The equation looks like this:
(Isp_1*thrust_1 + Isp_2*thrust_2 ...)/(thrust_1 + thrust_2 ...)
This will give you the correct Isp to use for your delta-V calculation.
The next very basic part of this tutorial is how to perform a transfer maneuver itself. This kind of action is called a �Hohmann Transfer� and it requires two burns at opposite points in an orbit. Adding velocity will boost our apoapsis higher. We would then simply wait until we hit our newly established Apoapsis and then add more velocity to boost our Periapsis to circularize. Or, we could drop our orbit by subtracting velocity by burning �retro-grade�.
We can also apply some Delta-V calculations to find out how much thrust we will need to perform this maneuver. We will break this burn up into impulses. For example purposes, we will start at a 100KM orbit and then boost into a 200KM orbit. Both circularized. The formula for the first burn is the following:
This is the formula for the final burn in the transfer:
Where:
u= Gravitational Parameter of Parent Body. (3530.461 km^3/s^2 for Kerbin).
r_1= The Radius of our first orbit. (100 km in this case).
r_2 = The Radius of our second orbit. (200 km in this case).
This formula will give us our velocity for the burn in km/s (multiply by 1000 to convert it into m/s).
It�s important to make sure that you will have the Delta-V in the stage to make this burn. Again, you can do that by using the Delta-V calculations on pages 1 & 2.
Next, we will explain how to calculate fuel flow in mass to see how much fuel a burn uses up in a specific amount of time.
If we know the delta-V needed for the burn and the total mass of the rocket before the burn, we can calculate how much fuel is required to complete the burn.
First, we calculate the mass of the rocket after the burn is complete. To do this, we use the (russian guy) equation, inputting the initial mass and delta-v of the burn. We can then solve the equation for the final mass after the burn. The difference between these two masses will be used to determine the length of time that is needed to complete the burn.
The equation for mass flow rate of fuel, given Isp and thrust, is:
m_dot = thrust/Isp
where m_dot is the mass flow rate of fuel consumed (in seconds)
Dividing the difference between initial mass and final mass for the burn by the mass flow rate of fuel, we arrive at how many seconds are required.
Note:
The mass flow rate of fuel can be converted into the consumption rate of the fuel units used in KSP (Liters, I presume). The conversion ratio is 1 mass unit per 200L of fuel.
Rather easy is the formula to calculate the orbital velocity of an orbit. This assumes circular orbit or the velocity of a specific point in an orbit. For this, we simply do this calculation:
sqrt(u/r).
Where:
u = Gravitational Parameter of parent body. (km^3/s^2)
r = radius of orbit. (km)
If we input the radius of the orbit in Kilometers, our orbital velocity will come out in Kilometers per second. In a 100km orbit, our radius will be 700km.
Meaning our velocity will be ~2.24578 kilometers per second (km/s), or 2245.8 m/s.
A delta-v map consists of approximate amounts of delta-v needed to get from one place (whether it be on the ground or in space) to another. The detla-v values we have for our delta-v map are approximate and include a fudge factor (in case we slip up on our piloting). Our map is as follows:
Launch to 100km Kerbin orbit: 4700 m/s
Trans-Munar Injection: 900 m/s
Landing on the Mun: 1000 m/s
Launch from Mun and return to Kerbin: 1000 m/s
Total delta-v: 7600 m/s
If we design our rockets to have 7600 total delta-v, and the acceleration of the launch stages are adequate, we can have confidence that our rocket is able to land on the Mun and return to Kerbin. A rocket with a little less delta-v can accomplish this goal, but it is less forgiving of less efficient piloting.
Calculating Thrust to Weight Ratio is only three very simple steps.
It is important to know the thrust to weight ratio of your rocket to ensure your rocket will actually liftoff. If your TWR is less than 1, you can bet that you won�t make an inch in altitude when starting from the launch pad. The minimum optimal TWR to have for your rocket at launch is 2.2.
The formula for this is simply the thrust of all of your current stage engines engines divided by the weight (mass * 9.81 m/s^2) of your stage, fully fueled. At the same time, this will give you the minimum G-force you can expect on the current stage. Your peak G-force will occur instantly before fuel depletion. The way to calculate this is to simply divide thrust by the dry mass of your stage+the fully fueled stages above it.
In conclusion: This guide will hopefully have helped with designing your rockets to allow you to get the job done -- whatever it may be -- with no test flights first. We hope this guide has been helpful to new and continuing KSP pilots alike.
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Orbital Mechanics is how to do it.
You\'ll need to understand phase angles and all kinds of crazy algebra stuff. It\'s very complicated, but the calculations can be done and interplanetary transfers is WELL within the current possibilities of KSP.
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Introducing the Aquarius Orbital Launch Vehicle. Fit for rendezvous and Kerbin orbit operations. Kerbal scientists think it probably has enough Delta-V to do a simple Munar fly by if you\'re really efficient, but that\'s not what it\'s meant for.
Here is some launch vehicle information:
On launch, you\'ll have about 2,552.672 m/s of Delta V to get you very high into the upper atmosphere. There are four engines on this stage called 'Outboard Engines'.
The thrust to weight ratio of this stage is 1.957 fully fueled. Meaning you can expect a MINIMUM G-force during this burn of a little under 2 G\'s.
As the fuel depletes, however, the G\'s build up. Peak G comes right before fuel depletion and subsequently before staging. The G\'s will then peak to approximately
4.2 G\'s.
Well survivable, of course.
The full mass of the launch stage is 44.875 and the empty mass is 20.875.
The total Engine thrust is 860.
You can expect an approximate average Specific Impulse on this stage of about 3,433.5 or 350 seconds..
This stage should cut off at about 96 seconds based on the mass fuel flow rate calculations. It will not be exact, however, as the engine ISP actually increases with altitude when the atmosphere becomes thinner.
Then, after staging, you\'re down to the Orbital Insertion stage:
The total mass of the vehicle after staging is then 12.375 with an empty mass of 6.375.
You will have a full engine thrust of 200. The thrust is vectored, which helps.
The engine ISP is about 3629.7 or 370 seconds now.
It has a thrust to weight ratio fully fueled here of 1.647.
Consequently, you can expect a minimum G force of 1.647 when this stage burns at full throttle.
Maximum G force if this stage gets all the way to fuel depletion at full throttle will be just under 3.2.
Here is a picture:
DOWNLOAD
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Hey everyone. I\'ve been real busy lately working on a real life spacecraft simulator thing and also just enjoying KSP with some rocket science to allow for perfect flights with no tests. I have had a few days break from texturing but I expect to do a little more work tonight. I just got the new shaded parts so I have to go ahead and import those into my game and then see what I have left to do with texturing for now.
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I was curious, shouldn\'t the retro pack be a LFE?
No.
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Introducing the new Tsiolkovsky B Mun Rocket. Designed for Munar Landing and return missions.
The whole thing packs a total Delta-V of approximately 9,372.169 m/s.
Lots of speed for anywhere you want to go, including Minmus!
Here\'s a picture:
And here\'s Jebediah Kerman on the surface of the Mun with the lander:
I have the Delta-V for each stage also written down if anyone needs to know how to fly their flight. Ride into a 90km orbit and then make TLI with the TLI stage. Use the TLI stage during Munar descent if you have to and land with the lander. That simple.
SHIP DOWNLOAD
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A.F.A.I.K. there is NO monolith in orbit around Minmus. I know someone has posted a screenprint of it in a thread, but that to my opinion is a joke/hoax. I have mapped Minmus extensively but never found a trace of it, neither with a muon detector nor with the isa-mapper. Furthermore, there is a mod (i can\'t remember which one) with a monolith part.
Or you just don\'t know where to look?
Do you miss the Space Shuttle Program
in KSP1 Discussion
Posted
This is truthfully hard for me to answer, and this is why:
As much as I think it is imperative that NASA has its own dedicated launch vehicle system, the Shuttle wasn't totally the answer. I do miss regular space flights being launched from the Cape, but the problem is, the Shuttle was not the best vehicle they could have used. First of all, it was fairly unreliable, causing 14 deaths (all due to completely "fixable" issues.) There was a lot of negligence that went into these disasters and it was never a very stable vehicle imho from the beginning. I think NASA should move forward with a more technologically balanced spacecraft with a much safer plan, but right now I fear they're just lagging and lagging and lagging with it. So yes, I do miss the shuttle because I miss NASA astronauts making spaceflights from their homeland. But I don't miss the shuttle because it was dangerous, unreliable, hefty, limited and followed a needlessly complex flight profile and also used up WAYY more money than was planned.
It's a shame too. I just hope that whatever NASA has in store for their next manned launch system is far more successful.