A First Relay | KSP Beginner's Guide

[@MikeAben]

Up Next: Orbit Phasing - kzbin.info/www/bejne/h3vEl4etnreImdE

[@DirtSlinger87]

December 2023 I am completely green to KPS. Got about 20 hours in so far. This series along with your contract series is by far the best guides I have found on YT. I may be late to the party, but I’m still having loads of fun. Even more now with an understanding of the basics.

[@MikeAben]

Welcome aboard.

[@junejensen2872]

Welcome to KSP!

[@bibsp3556]

Me too mate, after years of wanting to, I picked it up and these have been a lifesaver at times. It's so fun, taken a couple restarts though haha

[@thegood9]

Even though I am far from a KSP beginner, i am having a blast going through all your back content. It is refreshing to see someone with such detail and knowledge of the THEORY and PRINCIPLES of the REASONS why we do what we do in this simulation (NOT a “game”!). Thank you for the amazing things you do for the community!

[@MikeAben]

Thanks.

[@madmarshman]

Hi Mike, thanks for these videos, I've been binge watching your beginners series for the last few days. I purchased KSP in 2013, played for a bit, landed crewed missions on Mun and Minmus with the help of Manley and Lowne, then didn't play again for 7 years. Today i landed a probe on Minmus (touched down at 10m/s with no fuel) and got a satellite around Mun ap 377.417 pe 377.300 period 3h 0m 0s incline 0.0 .... all thanks you. Keep up the good work.

[@stevenjulie4698]

This series is so amazing! I was able to get my first satellite in orbit around Kerbin to within 11m of completely circular and an orbital period of exactly 90 minutes and couldn't be more thrilled! I was so lost in how to do this stuff before I found this series. Plus, I'm actually excited about the math! :D Thank you!!

[@ИгорьКан-ч3л]

Thank u so much! I searched all over the internet and only u could help me with argument of periapsis. From Russia with love

[@rhenderson1965]

Excellent series! You always seem to answer all my questions and then anticipate and answer questions I didn't know I had.

[@daniel.stafford]

Huge appreciation for this video - orbital mechanics felt a bit alien to me, but this now makes a lot better intuitive sense. 👍

[@kpd8726]

I want to ask from you what do you do with basic contracts which asks you to just send probe with some science equipment slapped on it to a certain orbit? Do you just build it as minimal as possible to save money or are you trying to use the contract as you advantage other ways? Ie. maybe adding some more science and antennas to use it perhaps for long time comms? =D This is my biggest weakness when playing KSP and my comm/contract network ends up always looking horrible and unreliable. Great tutorial series, its definitely useful for older players too!

[@MikeAben]

I tend to pick sat contracts that, with a bit of tweaking, can serve a second purpose like a relay. I don't like to have probes in orbits all over the place and so don't typically do a lot of those contracts. I am planning a video that will pick up from this one adding two more satellites around the Mun to create a proper network. Personally, I think the contracts are one of the weakest aspects of them game. In my current live stream I've overwritten most of them with contract pack mods.

[@kpd8726]

Tnaks for the fast reply. I'm happy that I'm not the only one who plays career and feels that contracts are weak and meaningless. Of course they give money and rep., but thats it. It does not feel right. In my mind they should encourage us to build comm networks and possibly long time science stuff etc. I tend too to fill that aspect with contract pack mods, in the end career is pretty much my only way to play because I need some "guidance" for what to do! I know that career is not most important aspect for devs right now, but I honestly hope and believe that KSP will have better career system in the future. Maybe even DLC.

[@MikeAben]

@@kpd8726 I'm with you.

[@timmy3822]

Great video, I always struggled to get my Apoapsis and Periapsis to be the same... I'm a bit obcessive like that so it was irritating me. Your videos are criminally underviewed and liked. 36K views and only 846 likes? Come on people! We can do better than that!

[@Kriss5054]

I never more use the manoeuver nodes to change my orbit inclination. I just use it to find out the right reference (normal / anti-normal) and stick to this reference while applying thrust (it will move). This way, you can do a 180 degrees change without affecting your apoastre / periastre.

[@MikeAben]

That works, but it costs more fuel, especially as the inclination change gets larger.

[@Kriss5054]

Hello @@MikeAben I didn't think about that... But I've tested it, and the result is not the one expected ! I moved a Mune satellite from 90° to 130° inclination (according to advanced orbit information) following the anti-radial reference manually with small amount of thrust and it cost me roughly 300 m/s. Making the same manoeuver using nodes took me 380 m/s to change the inclination + 140m/s to correct the orbit parameters (Apoastre and Periastre). That's a total 520 m/s, a lot more than 300 m/s. Maybe my orbit correction was not ideal but even without that, using nodes to change inclination was already more than following the normal reference. What could I have done wrong ? Could gravity play a role in that difference ? Anyway, when you are a beginner (as I am...) playing in a career mode, with experience taken into account, it is far much easier (from my point of view) to follow manually references. I'm a great fan of your videos by the way ! It's cristal clear and your accent is easy to understand for me (I'm French...). Thanks a lot.

[@vortexcv]

@@Kriss5054 you also need to check the position of your maneuver node. The perfect position will not cause any orbit changes other than inclination. Woth your method you are somehow aligining the position of your burn, but when you use maneuver nodes, you need to adjust their position also.

[@Kriss5054]

@@vortexcv You’re right. But in that case, it is far much simple to stick to the normal / anti-normal reference… For information, when flying manoeuvers, I use the option to split it in two equal time.

[@Biomirth]

A little correction (hope I'm not wrong) @5:47 "Prograde and retrograde burns are best done as close to the parent body as possible". I don't think so. They're best done from the opposite side of the orbit. If you want to adjust your periapsis this should be done literally as far from the parent body as possible (apoapsis). Similarly I think your advice r/e inclination changes isn't right regarding proximity to the parent body. I believe they're best done at the nodes, full stop. Your videos have been really helpful to me so thanks so much for posting them. If I'm wrong here feel free to delete. One last thing: If raising both apoapsis and periapsis the math I think says there isn't a difference in delta-V required whichever you do first no matter their height.

[@MikeAben]

To clarify, by best I mean most efficient. To be more specific, the higher your orbital velocity, the more efficient a prograde or retrograde burn, and the lower your orbital velocity, the more efficient a normal (or radial) burn. As lower altitude means higher velocity (and vice-versa) the efficiency of your burns is connected to your altitude. There are all kinds of situations where you can take advantage of maximizing this effect. So although, yes, burning prograde or retrograde does raise or lower the opposite end of the orbit, it still is to your advantage to have this burn at as low an altitude as possible, while the opposite is true for normal burns. There are also many situations where normal burns are not done at either of the nodes, nor is it more efficient there.

[@Biomirth]

@@MikeAben Thanks for the clarification Mike. I'll see if I can make the math in my head work :) " the higher your orbital velocity, the more efficient a prograde or retrograde burn, and the lower your orbital velocity, the more efficient a normal (or radial) burn. As lower altitude means higher velocity (and vice-versa) the efficiency of your burns is connected to your altitude." The problem I have is with 'efficient'. Yes you maximize the motion through space of your orbit doing it at maximum velocity but to affect a particular part of an orbit (say periapsis or any other specific spot other than apoapsis) the only efficient place to do this is on the opposite side of the orbit from that location. Likewise with inclination there are 2 spots that have maximum effect and this is independent of orbital velocity relative to all other points. 1 inclination spot may? be more efficient than the other, but there are not spots closer to the planet body that should be more efficient than the closest node. Apologies again if I'm still wrong and just thick.

[@MikeAben]

@@Biomirth No problem, and you're right, but with some forward planning you can manipulate where these positions are. For example, let's say I have a contract to a satellite in 500 km X 1000 km orbit around Kerbin and it's currently sitting in an 80 km X 80 km parking orbit. No matter how you shake it, you have to do two burns, but you can control where those burns will take place. The first burn should raise the apoapsis of the parking orbit to 1000 km (not 500 km). Why? because the larger share of the energy need to get inserted into the higher orbit is being added when you are as close as possible to Kerbin. Here's a normal example. I'm in an 80 km X 80 km orbit of Kerbin and want to change my inclination by 45 degrees. You will burn less fuel my pushing your apoapsis far away from Kerbin, perform the inclination change out at apoapsis, and then recircularize down at periapsis. Why? because normal burns are cheaper far away from the parent body, and in this case that saving more than offsets the cost of the extra prograde and retrograde burns.

[@MikeAben]

@@Biomirth Getting to the example from this video (sorry, I had to rewatch it) the point I was trying to make (likely not very clearly) is that I do want to bring my inclination to 180 degrees, which I did at one of the nodes, but it was best to get my orbit up higher before doing that as it saved me fuel.

[@Biomirth]

@@MikeAben OK, gotcha. That makes a lot of sense. A combination of two maneuvers does bring up the question of efficiency directly. Thanks for your replies.

[@AbsoluteHuman]

There's a typo at 16:10 when the captures says "with" instead of "without"

[@MikeAben]

Yup, thanks. I gotta fire my proof reader.

[@rumguk]

Awesome video, thank you for this series it`s absolutely fantastic!

[@eskka92]

Thanks for the video, it helped me alot :)

[@TheDegenerateLord]

your a good teacher.. Absolutly greatful for you and others like you thank you! Crazy how this game is pretty much on par with a college level course as far as difficulty or how complex the concepts being thought are. Only difference is I actually bought this because I wanted to and it's not putting in me I'm wild debt.

[@OceanDrive321]

Do I need to use relays on my satellites? Can I install smaller and more energy efficient direct antenas? Or do they have no ability to pass the data?

[@MikeAben]

A direct antenna can transmit data directly to the KSC or to a relay antenna, but they can't transmit to another direct antenna. Let me know if that doesn't answer your question.

[@OceanDrive321]

@MikeAben ok I'm launching those 600L RA-2 around Kerbin rn

[@OceanDrive321]

@@MikeAben thank you!

[@rbroach68]

Could a polar orbit be used and give constant communications with just 1 satellite?

[@MikeAben]

No. You always need at least three satellites.

[@phich3619]

​@@MikeAben I think you can use one satellite which orbits in the equator of the mun and the other orbits in polar, it will become a cross signal which u could cover the signal of whole surface of the moon instead of using 3 satellites.

[@MikeAben]

@@phich3619 Sorry, but you need at least three, it doesn't matter the orbits. Place your satellites anywhere you want. Now, place a sphere anywhere you want. There will always be points on the sphere that cannot be connected to either satellite, and if you place the sphere between the satellites, then the two satellites can no longer connect. This can be reduced to a two dimensional problem. Draw a circle. What's the simplest polygon (ie. made of straight line segments) that you can draw around the circle? A triangle. It really is as simple as that. Going three dimensional actually requires more satellites, not less. Technically, three satellites in an equatorial orbit, cannot reach either pole, but in practice, in game, the collision between the communication lines and the surface are pretty generous and you'll find it'll work anyway.

[@phich3619]

@@MikeAben i saw your video about this and yet I tested it out myself and it is true that you need at least 3 sat. Tks man

[@voidseeker4394]

However, it is usually quite easy to launch them all 3 at once. Just get proper resonant orbit(there is online calculators for that!), release one satellite each periapsis, and you won't need to align them relatively to each other. Release one satellite at periapsis, switch to it immediately and circularise orbit ASAP. Then switch back to launcher ship, wait for exactly next periapsis, release another satellite, and so on.

[@joechirdo7641]

Love the videos, keep them coming!

[@danpettersson4671]

Evening coffee time! *looks around for a snack, and is unable to find one. Sighs, and pauses video* Now I'm back with coffee, and two thin pancake rolls (Swedish style pancakes are much more like crépes than the fluffy American pancakes) filled with strawberry jam, and whipped cream.

[@danpettersson4671]

Why do you bother to put them in an equatorial orbit. As long as the satellites are in the same orbit and period (and high enough that they have LoS to each other) the placement of the first shouldn't matter, should it?

[@MikeAben]

@@danpettersson4671 Very true. Though, I know it would always bug me. Still it's a good thing to bring up. By the way, my parents were first generation Canadian and I grew up on Dutch pancakes (also like crepes with jam, sugar, etc on them). I distinctly remember going to school and being confused by North American pancakes.

[@danpettersson4671]

I almost forgot the most important item on my agenda, thank you for the entertainment and the information. PS: The Pancake rolls was very enjoyable :)

[@Chase_The_Calm_Gaming]

Where's how the relay works?

[@fatmike5038]

if you use a polar orbit you only need one.

[@MikeAben]

No. Anything on the opposite side of the body from the relay clearly wouldn't be able to see it.