General Question TransX or IMFD

[Interceptor]

What do you guys prefer, and which one is more user friendly.Basicaly Pros and Cons.want to start traveling to the moon.Thanks

 

[PhantomCruiser]

For me, from the Earth to Luna (or Mars to Phobos/Deimos) is easier to use Transfer. But from Earth to mars, Venus, etc... I'm learning IMFD, there is a really good tutorial out recently that is pretty all-inclusive. Do a search for it at OrbiterHanger and you should be quite pleased.

 

[Hmuda]

IMFD

Pros:
- Easy to use, almost "click and go" simple.
- Tonns of functions that all do the work for you.

Cons:
- Can't think of any. It will get you where you need to go easily.

TransX

Pros:
- The user has more influence on the different aspects of the travel to mess around with.

Cons:
- More complicated and takes a while to get used to.

(I'm sure others will expand the list.)

Personally I use both. I use TransX for just the heck of it, since "that's how real men do it".

But I also use IMFD when I really don't feel like fiddling in TX and just want to get somewhere easily.

 

[Nemoricus]

IMFD is very easy to use. Just pick the conditions you want to work with and it will give you a solution. Whether or not it's the best solution is often debatable, and fiddling around with the numbers is a good idea. It also has a much more accurate predictive model than TransX does, at least in Map mode.

IMFD is also a lot more flexible. You can use it to plan a reentry, which TransX can't do. Its velocity match and circularization functions are very nice as well.

TransX is less complicated, but harder to use at the same time. While IMFD will calculate and execute a burn for you, TransX is very much do it yourself. It gives you the results of what would happen if you with a certain net delta-v at a given time far more easily than IMFD can. It also does slings very well. From what I've heard, it's much easier to use than IMFD for such a purpose.

 

[TMac3000]

I use a combination of both.

I use TransX to set up my departure, and IMFD Map mode to look at my "real" closest approach, and plan course corrections. This method has gotten me to Mercury and Mars, and that's saying quite a bit

 

[Interceptor]

So, I should Probably start with IMFD? first untill I start getting the hang of it.Thanks guys I'll start working with it tommorow.

 

[Nemoricus]

[ame=http://www.orbithangar.com/searchid.php?ID=4142]This[/ame] will be a very useful reference when you're trying to learn IMFD, by the way. The tutorials are particularly helpful.

 

[agentgonzo]

If you're *just* going to the moon and back, then take a look at Lunar Transfer MFD. It's set up specifically for going to the Moon and so is more accurate at that, but can't be used for other planetary transfers. IMHO it does a bit too much and can reduce a lunar mission to a point-and-click exercise, but it's accuracy is fantastic and can't be beaten.

 

[Interceptor]

No I want to understand and have to work at it a little. Lunar Transfer MFD seems to be a liitle to easy.Thanks

 

[kneejo]

In TransX, after you've performed the manouvre, you can switch off manouvre mode and you will see your 'real' trajectory, allowing you to fine-tune your arrival with RCS thruster for instance.

However, when I did a long, 5 year trip from Neptune back to earth, it would behave very weird, showing my arrival situation to change as time passed on. This lead me to continuously having to correct,, but I'm not sure if that was necessary. Any advice from experienced TransX users is welcome here..

Apart from that, once I learned to work with TransX I have no use for other MFD's anymore. Re-entry I can manage using the mapmfd and VOR when I get close to base. Aerobrake seems promising, so I'll dive into that sometime soon.. can't learn everything at once! ")

 

[agentgonzo]

However, when I did a long, 5 year trip from Neptune back to earth, it would behave very weird, showing my arrival situation to change as time passed on. This lead me to continuously having to correct,, but I'm not sure if that was necessary. Any advice from experienced TransX users is welcome here..

That's normal behaviour of TransX due to the relatively simple model of the solar system that it uses. As your flight (and Neptune's orbit) gets slightly perturbed by the other masses in the solar system, the expected encounter at Neptune changes.

A good rule of thumb for TransX is to perform a course correction burn as soon as you get out of the gravitational influence (SOI) of your departure planet, then perform MCCs every time your time to encounter at the destination planet halves (if required).

 

[Omhra]

Trans X for general navigation. IMFD for orbital maneuvers...

 

[flytandem]

I am quite learning challenged but I have a good visualization of motion in 3d. I really enjoy TransX. It allows me to simply toss in 3 dimensions of deltav and the solar system becomes a playground. I've tried IMFD but the many steps have me overwhelmed. Plus IMFD takes away the enjoyment of implementing the skills I have in seeing in 3d because it sets it all up automatically.

When I was a kid my dad told me a story. One man asks the other..."where did you go on vacation?" The other answers "Majorka." The first man then asks.."where is Majorka?" He answered "i don't know, I flew."

Maybe if he had set up the flight to Majorka using TransX he would know where he had gone on vacation.

That being said, I really like the accuracy of the data in the Map display in IMFD. Huge benefit on nearly all my Orbiter flying.

 

[insanity]

Both! For a flight to the moon and back I usually plan my inbound leg with IMFD and my outbound leg with TransX. It's all about which tool is the best for the job I want to accomplish.

Learning how to use them both can help get you anywhere in the solar system.

 

[Interceptor]

Boy, I have my homework cut out for me. WOW!

 

[jedidia]

I used TransX before I switched to IMFD. from my experience, TransX is basically the Delta-V program of IMFD 5.1 and higher, unless you want to do slingshots and other complicated tricks.

One big con of TransX to IMFD is, imho, the lack of burn-time integration. It's the major point that made me switch to IMFD. Especially because I am experimenting with low-thrust high ISP flights lately.

However, for learning the ropes of interplanetary travel, TransX is the better option, because it forces you to understand what you are doing, while IMFD only forces you to master its interface for most parts, without a real understanding of the processes involved.

For simple earth to moon trips, I still find good ol' Transfer MFD to be easiest to use. Allthough it's a pain to get back to earth with it.

 

[Nemoricus]

TransX does have burn time integration, unless I'm very much mistaken.

 

[agentgonzo]

TransX does have burn time integration, unless I'm very much mistaken.

It does, but only for high thrust engines. It does not work for low thrust engines such as ion engines or VASIMR. This may be what jedidia was meaning (or s/he may be using an old version of TransX before the burn-time readout)

 

[jedidia]

(or s/he may be using an old version of TransX before the burn-time readout)

I'm a he :lol:

common problem on boards where I use that name, though.

I was using a version without , but later one that had it too. But as far as I know, it did not calculate the gradual change of velocity into the actual course, as IMFD seems to do. This is probably what you meant by "does only work for high-thrust engines".

allthough, I have yet to experiment a lot with IMFD to find the best possible way to do it. There simply isn't a Nav tool yet for orbiter that was built with that purpouse in mind, but IMFD seems the best bet for an improvised solution.

 

[agentgonzo]

But as far as I know, it did not calculate the gradual change of velocity into the actual course, as IMFD seems to do.

You are correct in that it does not do this. It assumes that all of the Delta-V is delivered in a single instant (the Time to manoeuvre value) and then works out the time to begin the burn to best approximate this.