Energy MFD mk2

[Enjo]

I'm making an updated version of [ame="http://www.orbithangar.com/searchid.php?ID=1473"]Energy MFD[/ame]: Energy MFD mk2

Here's a screenshot:

Explanation of the screenshot:
As I move to the apoapsis, my velocity decreases, and my kinetic energy decreases, but due to increase in my radius, my potential energy increases. The sum of kinetic and potential energies (mechanical energy) is constant, as long as I don't fire engines. I fired them at T ~ 48000 s, namely, I increased the energy, by accelerating prograde, making the orbit even more elliptical. You can see the sudden kinetic energy increase.

What's the use of this MFD? None. It's for educational proposes only. I need such tool for my lecture, and I thought I'd share. Release - soonish!

 

[SlyCoopersButt]

It looks like it has use to me. I think it will be a brilliant MFD to have.

 

[Mafuskas]

It is certainly interesting. Physics can be quite elusive to the mind without the visualizations provided by graphs and even the whole Orbiter sim itself. An MFD like this allows you to stare physics dead in the face, and certainly makes considering the laws acting upon you in Orbiter all the more immersive.

 

[sputnik]

Actually, since the Velcro Rockets autopilot is energy-based, and is making these calculations in the background, I could have used this thing as a handier debugging tool than using the oapidebugstring output.
Might still come in handy, I'm not sure. I'm looking forward to playing with it, anyway.

 

[Andy44]

Maybe there's a way to tie it in to manual re-entries? GPC MFD is energy-based, but it's tailored to use by Space Shuttle and similar vehicles. Maybe you could set up parameters and try to stay within them using an MFD like this somehow.

 

[dbeachy1]

This looks great! I'm looking forward to the release!

 

[tgep]

Mass and Energy being equivilant, It would be a usefull tool for a sci\fi ship when fuel consumption is not an issue. You could use it to play with burn time calculations, figuring orbital sling shot burns, etc.

 

[Enjo]

You know, this place is the only place that I know of, where physics isn't treated as a public enemy.


Behold! Yet another mad experiment!

After the ejection burn seen at t = 5e3 s, and being at t = 8e4 s, you can see that the potential energy goes down to 0, and kinetic doesn't at all. Duncans would be proud, lol.

You can clearly see this phenomena on the graph, thanks to new mode of graphs operation: "Zero based" (anyone got a better idea for its name?). It means, that the graph Y values won't be tied to min and max of data samples, but <0 and max> for KE, and <(-) min and 0> for PE accordingly.
The ME is in "full auto" mode ("absolute" may be a better name), meaning, that for Y boundaries, the graph takes not only its own data, but data from all graphs. If you set this mode in all graphs, you'll see how big are the energies, relative to each other, because they'll be in the same boundaries.

You can select the graph with SEL button. It's either a particular graph, or all of them. So if you want to set two of the graphs to the same mode, and other graph to another mode, then you can for example select all graphs, set the mode for the two, and then select the remaining graph, and set the appropriate mode. Of course, you can also set the modes separately.

For Sputnik, and Andy44, I've added "sampling time". Should come handy for low alt operations. It can't go below 1 second. You'll have to tell me if this is acceptable.

As for display modes, there are: Graphs, Words (values and config), Both. Below you can see the Words mode:

The red message is to inform why the MFD stopped working. I must have had made such a check to protect Orbiter from crashing. Probably because of floats overflow. Ascent MFD (Custom MFD) suffers from the same problem.

All I need to do now is implementing a ReSeT button, to quickly clear the graphs, when you enter new body's SOI.

 

[Urwumpe]

Can you also use the gravity field of the solar system (all celestial body fields summed) as input for the potential energy calculations? Might be interesting to see how it is to enter a new SOI.

 

[Enjo]

You can't do it now, but if I intended to allow for it, then how would I find the .. ehm.. radius for PE calculations ?

 

[tgep]

How about a constant value based on the orbit of say ......... Jupiter ?

 

[Enjo]

Ok, you can target any object. To get graphs though, it has to be withing the range (400e6 m)


and it's released:

http://www.orbiter-forum.com/showthread.php?t=2970

 

[agentgonzo]

Looking good. Would be nice to get the energy graphs of Voyager 2's grand tour as it got the energy boost from the slingshots

 

[Enjo]

Unfortunately it's impossible to draw this, as you'd need to refer to Sun, which would be too far away for the graphs to be stable. You can get a decimal readout, but not the graphs.

 

[Enjo]

Agentgonzo:
Here's a readout relative to Earth, after lunar, prograde slingshot at 1.9e5 s

That's some energy I gained, didn't I?

I was trying to plot the graphs even for more distant bodies, but there wouldn't be any automatic scale adjustment, if it's meant to be stable. I'll probably contact Martins about this issue. I may be the only one using GraphMFD extension.

[EDIT]
I had to increase the maximal limit of plotting to 500e3 from the previous 400e3, risking some stability issues.

 

[tgep]

I like it. I've had no issues with it so far and it plays nice with the other MFDs and plugins on my bloated intall.