Delta-V map concept

[Altaïr]

Hi!

I'm currently working on a delta-V map, but it's hard to represent as much information as possible while being accurate and clear. I drawed a delta-V map for Mars and its moons so that you can give me your opinion and feedback:

It's designed so that you can calculate very easily the cost of a direct transfer, an Oberth maneuver, or a bi-elliptic transfer. The drawback is that it may be very confusing at first, especially for beginners (I could draw a simplified map for them).

The concept is the following:
- To get the delta-V cost of a given path, you have to sum-up all numbers encountered on this path
- a red path is a maneuver that must be performed at Mars level, a brown path at Phobos level etc...
- the blue branch ("SOI") represents an orbit which apoapsis is at Mars'SOI level. The numbers encountered on that branch represent a burn at the apoapsis. This is for bi-elliptic transfers.

For example, with that map, you can see that if you want to go from Deimos to low Mars orbit, the bi-elliptic transfer is slightly more efficient than a direct transfer.

I'll give you a few examples tomorrow (it's really time to sleep here ). Meanwhile, feel free to ask any question, make suggestion etc...

 

[Bananas]

I'm the noob of all noobs so I don't understand this

 

[Lukapower]

Nice

 

[Lukapower]

I used it and it’s quite precise

 

[Lukapower]

Sorry wrong foto

 

[Lukapower]

A Ryanair landing on mars

 

[Lukapower]

Using your map

 

[Lukapower]

It’s my fault it crashed

 

[Altaïr]

Thanks for the feedback guys

@Bananas , I understand it looks complicated, I'll draw a simplified map with only direct transfers, which should help a lot. Meanwhile, here are a few explanations.

First, I suppose that the "orbit" nodes are not a problem. What is probably not clear is those nodes in the middle:

They correspond to transfer orbits. For example, the node n°1 is the transfer orbit between Low Mars Orbit (LMO) and Phobos. You can deduce this from the fact that this node is at the crossroads of Mars and Phobos branches.

Similarly, the second node is the transfer orbit between LMO and Deimos, and the third one between Phobos and Deimos.
The fourth one is a transfer orbit which periapsis is at LMO level and apoapsis near the SOI limit.

Let's see in practice.

A trip from LMO to Phobos:
I start from Low Mars Orbit:

I'll join Phobos with a normal transfer trajectory, which corresponds to this path:

First step is burning at Mars level to put my ship on the transfer trajectory. From the map, it costs 230 m/s:

Then the second step is satellization around Phobos:

According to the map, this costed 118+3 = 121 m/s.

Returning from Deimos to Mars orbit:
Now let's suppose I'm orbiting Deimos and I want to go back to LMO:

A direct transfer would cost:
- 2+37+64=103m/s (yellow branch) to put my ship on the transfer orbit
- 44+230=274m/s to circularize at Mars level (can be done by mostly aerobraking)
This represents a total of 377 m/s.

Now, let's try that bi-elliptic transfer instead:

The normal transfer is the red path, the bi-elliptic one is the blue path.
First step consists in burning so that I approach the SOI limit:

This maneuver costs 33+2=35m/s.
Now, the second maneuver, I burn retrograde at the apoapsis, which costs 19+19=38m/s:

Finally, the third maneuver, which costs 230+44+18=292m/s (can be reduced by aerobraking):

In the end, this costed 365 m/s. This is slightly less than the direct transfer that would cost 377 m/s.

I know that this map can be improved (I suck at drawing and I didn't have so much time to do it), but any opinion would be appreciated (even a negative one: if you think this is too complex, you can tell me). If you have suggestions to make it better, this will be welcome too

 

[Bananas]

Thank you!

 

[Tymekx0]

Hi!

I'm currently working on a delta-V map, but it's hard to represent as much information as possible while being accurate and clear. I drawed a delta-V map for Mars and its moons so that you can give me your opinion and feedback:
View attachment 9898

It's designed so that you can calculate very easily the cost of a direct transfer, an Oberth maneuver, or a bi-elliptic transfer. The drawback is that it may be very confusing at first, especially for beginners (I could draw a simplified map for them).

The concept is the following:
- To get the delta-V cost of a given path, you have to sum-up all numbers encountered on this path
- a red path is a maneuver that must be performed at Mars level, a brown path at Phobos level etc...
- the blue branch ("SOI") represents an orbit which apoapsis is at Mars'SOI level. The numbers encountered on that branch represent a burn at the apoapsis. This is for bi-elliptic transfers.

For example, with that map, you can see that if you want to go from Deimos to low Mars orbit, the bi-elliptic transfer is slightly more efficient than a direct transfer.

I'll give you a few examples tomorrow (it's really time to sleep here ). Meanwhile, feel free to ask any question, make suggestion etc...

Im pretty sure I saw something like this on reddit, but that didn't have jupiter so

 

[Altaïr]

Im pretty sure I saw something like this on reddit, but that didn't have jupiter so

Yes, I have it in my files too. But it was done during 1.35 (which is why there is no Jupiter), and as the Sun has been made heavier, it's not reliable anymore.

That's why I wanted to make a new one, but I also wanted a map that gives most transfers cost. For example the previous map didn't give the price of a transfer from Phobos to Deimos.

 

[Tymekx0]

Yes, I have it in my files too. But it was done during 1.35 (which is why there is no Jupiter), and as the Sun has been made heavier, it's not reliable anymore.

That's why I wanted to make a new one, but I also wanted a map that gives most transfers cost. For example the previous map didn't give the price of a transfer from Phobos to Deimos.

I wasn't fully sure since I was quickly browsing reddit in school, Keep on working

 

[Gecko Gekkota]

View attachment 9915

Irelevant

 

[Altaïr]

Hi guys,

I made a simplified delta-V map for the Mars system, here it is:

Do you prefer this one?

One thing to be aware of is that there are "only" 2 moons around Mars, so there are not much transfer trajectories, but doing a delta-V map for Jupiter and its moons that way will be a mess. That's why I preferred doing a "matrix-like" delta-V map at first, even if I'm aware that it's far less intuitive at first

 

[Bananas]

Thank you! This makes things ay more simpiler for me!

 

[8BitCosmonaut]

Hi!

I'm currently working on a delta-V map, but it's hard to represent as much information as possible while being accurate and clear. I drawed a delta-V map for Mars and its moons so that you can give me your opinion and feedback:
View attachment 9898

It's designed so that you can calculate very easily the cost of a direct transfer, an Oberth maneuver, or a bi-elliptic transfer. The drawback is that it may be very confusing at first, especially for beginners (I could draw a simplified map for them).

The concept is the following:
- To get the delta-V cost of a given path, you have to sum-up all numbers encountered on this path
- a red path is a maneuver that must be performed at Mars level, a brown path at Phobos level etc...
- the blue branch ("SOI") represents an orbit which apoapsis is at Mars'SOI level. The numbers encountered on that branch represent a burn at the apoapsis. This is for bi-elliptic transfers.

For example, with that map, you can see that if you want to go from Deimos to low Mars orbit, the bi-elliptic transfer is slightly more efficient than a direct transfer.

I'll give you a few examples tomorrow (it's really time to sleep here ). Meanwhile, feel free to ask any question, make suggestion etc...

It's too messy

 

[8BitCosmonaut]

Irelevant

Stealing my lines now?

 

[8BitCosmonaut]

Hi guys,

I made a simplified delta-V map for the Mars system, here it is:
View attachment 9998
Do you prefer this one?

One thing to be aware of is that there are "only" 2 moons around Mars, so there are not much transfer trajectories, but doing a delta-V map for Jupiter and its moons that way will be a mess. That's why I preferred doing a "matrix-like" delta-V map at first, even if I'm aware that it's far less intuitive at first

On step 2, you should point the the arrow from towards the mars line towards phobos, otherwise it will ruin the reader's sense of continuity.

 

[8BitCosmonaut]

When I was playing KSP RSS/RO, this map was one of the best made. I strongly recommend you go with this format.

 

[Bananas]

When I was playing KSP RSS/RO, this was one of the best maps made, I recommend you use this format.

View attachment 10001

That is very well made!

 

[Altaïr]

Ok, thanks for the return guys.

I'll go with the simplified map then. Thanks for the suggestion @8bitCosmonaut , this is a good one indeed. However, my initial idea was to draw a map for the Solar system (with planets, without showing the satellites), and a map for every planet system (except for Mercury and Venus as they have no moons). This will result in more balanced maps.
The solar system map would also be designed in the same way as the planet system maps (planets are just Sun's satellites after all). This would also give you the cost of a Mars-Venus transfer for example. The problem of the map you show me is that it only gives "Earth to XXX" transfers.
I think I have an idea so that multiple arrows don't generate a big mess by crossing eachother

On step 2, you should point the the arrow from towards the mars line towards phobos, otherwise it will ruin the reader's sense of continuity.

Actually that arrow is supposed to be a "prograde/retrograde" indicator: while following the path, encountering an arrow pointing in the same direction means a prograde burn, and an arrow in the opposite direction means a retrograde burn.
For example, if you go from Phobos to LMO (the opposite path to the one given as an example), you'd meet the arrows in the opposite direction, so you'd have a prograde burn at Phobos periapse followed by a retrograde burn at Mars periapse.

 

[Gecko Gekkota]

Stealing my lines now?

no, it's just a useful word

 

[8BitCosmonaut]

Actually that arrow is supposed to be a "prograde/retrograde" indicator

Unnecessary, once you show a player how the map works, he will be able to automatically know how to use it just by showing one or no arrows at all.

 

[Altaïr]

Unnecessary, once you show a player how the map works, he will be able to automatically know how to use it just by showing one or no arrows at all.

I understand, I don't need that arrow too.
But if I draw a simplified map, I would like a non-experienced player to be able to understand it without further explanations (that's the problem of my first map: it's very practical to me, but without explanation it's just a big mess). If it needs explanations, I'm afraid lots of players will just ignore it.
That's why it's designed so that anyone can quickly know:
- where that burn must be performed?
- in which direction?
- how much delta-V do I have to spend?

That's why I want to give as much informations as possible while being as much self-explicit as possible.

Now, people like me and you that don't need that arrow can just ignore it