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Brain
08-20-2010, 09:16 PM
Can a RockSim user import 3D models of flight objects? I love to do 3D modeling and it would be so easy to create my ideas there and import them. I'm betting it doesn't work that way, though...

-Brain
Aim for the sucker holes.

CPMcGraw
08-20-2010, 09:22 PM
Can a RockSim user import 3D models of flight objects? I love to do 3D modeling and it would be so easy to create my ideas there and import them. I'm betting it doesn't work that way, though...

-Brain
Aim for the sucker holes.

RockSim uses a database of "components" to generate the imagery from, and then calculates the aerodynamics from the result. The only "import" capability RockSim has (at present) is to import database files of components.

Even that capability is limited, and the process is easier done with a spreadsheet.

The database files are standard "CSV", or Comma-Separated Variables, readable on almost every spreadsheet program available. I use OpenOffice Calc, but I have used Excel in the past.

RockSim files themselves are just XML text files.

Brain
08-21-2010, 06:18 PM
I have another question: I have noticed that all the 3D images of the RockSim designs I've seen do not show the beveling that the leading edge of fins need to have. Does RockSim not calculate things that far? Or, wouldn't it better for calculations if it did?

-Brain
Aim for the sucker holes.

CPMcGraw
08-21-2010, 08:25 PM
I have another question: I have noticed that all the 3D images of the RockSim designs I've seen do not show the beveling that the leading edge of fins need to have. Does RockSim not calculate things that far? Or, wouldn't it better for calculations if it did?

-Brain
Aim for the sucker holes.

RockSim's 3D engine is nowhere near being in the same league as Maya or Blender; not by any stretch of the imagination. It uses those rounding, or beveling, numbers in the flight dynamics; but the graphics are kept simplified so as not to put a bigger strain on the user's computer. 3D graphics eat up far more processor power than the flight calculations.

Brain
08-21-2010, 11:30 PM
I wasn't looking for 3D realism in RockSim (although I have my doubts that a beveled edge would impact someone's CPU that much, especially considering the render style used), I was merely trying to glean some background on the program. And I have my answer! Thank you.

-Brain
Aim for the sucker holes.

CPMcGraw
08-22-2010, 06:36 AM
I wasn't looking for 3D realism in RockSim (although I have my doubts that a beveled edge would impact someone's CPU that much, especially considering the render style used), I was merely trying to glean some background on the program. And I have my answer! Thank you.

-Brain
Aim for the sucker holes.

Actually, those 3D images do put a strain on the average user's computer. I have a single-core Athlon 3200 system with 2 GB ram and an older nVidia 6200 card (dual-head, driving twin LCD monitors), and it has a hard time pumping out the images. When you consider that most of the computers being used don't have a separate graphics card (motherboard graphics systems with shared memory), it's great that RockSim can do what it does. TVM and crew dialed down the software intentionally to allow virtually anyone to use the program.

luke strawwalker
08-22-2010, 06:08 PM
Which is a good idea, because I have enough problems as it is!!! :D

Rocksim CAN be a bit, ahem, "glitchy" from time to time (depending on your OS and platform), and if it were 'more sophisticated' it would probably be a LOT moreso...

Later! OL JR :)

Brain
08-22-2010, 10:09 PM
OK, I'm trying to learn RockSim so that I might become a fully-fledged member of the rocket design process around here, and I am interested in NOT doing the ordinary. How does one:

1) Create something like a tube fin with any particularities I need (see the 'Dead Ringer' post in the Designer's Studio section); and

2) How does one create a set of attached fins perpendicular to a set of normal fins? Again, see the relevant post...

Thank you.

-Brain
Aim for the sucker holes.

Brain
08-22-2010, 10:16 PM
Which is a good idea, because I have enough problems as it is!!! :D

Rocksim CAN be a bit, ahem, "glitchy" from time to time (depending on your OS and platform), and if it were 'more sophisticated' it would probably be a LOT moreso...

Later! OL JR :)

Maybe... I use a prog called Swift3D from Electric Rain that would - by definition - kick RockSim's butt in the 3D department. And except for some troubles lately with Symantec running crap all the time (it seems ) on my computer, Swift3D seems quite robust. It's all in the coding, I guess.

-Brain
Aim for the sucker holes.

CPMcGraw
08-22-2010, 11:04 PM
Also keep in mind, RockSim was not designed primarily as a 3D rendering engine, but as a rocket flight simulator. Most of the real worth of the program is still connected to the ability to reasonably model the performance of a given design, and to predict a design's general behavior.

Nothing will give us the final proof until we build one with real components and fly it 'in the wild' with real engines, and to be sure, RockSim has been known to produce a few gotchas. I've had models that said everything was 'right', then pretty as you please the real model starts chasing its tail as it comes off the rod. RockSim's 3D engine can be beaten by almost any 3D program, as you've seen. It cannot do everything. But what it does do, rendering-wise, follows what it was designed to do, which is to simulate a design through the flight envelope. As Apogee continues to develop this program, I expect to see greater rendering abilities in the future.

Brain
08-29-2010, 10:10 AM
Another question: I'm trying to learn RockSim by playing with other peoples' files, and in some files I can find the facility to customize fin shapes (because it's already been done in the file)... and in others I cannot. Can I alter ANY fin set? Or just certain ones? And how do I find the button that can do this with ?

-Brain
Aim for the sucker holes.

brianc
08-29-2010, 10:37 AM
There are two standard 'fin' buttons on the RS main design panel.

'Fins' allows you to input parameters for typical trapezoidal or elliptical
fins. 'Custom Fins' allows you to plot the fin outline points.

Ring fin buttons are just below these.

Brain
08-29-2010, 02:07 PM
There are two standard 'fin' buttons on the RS main design panel.

'Fins' allows you to input parameters for typical trapezoidal or elliptical
fins. 'Custom Fins' allows you to plot the fin outline points.

Ring fin buttons are just below these.

When I have the Fin Set selected in the hierarchy these buttons are not active.
How do I activate them?
Is there a step I am missing to do this? I see it functional in other files... how on this one?
Do I have to specify something in particular on the Fin Set? Can I not use a previous fin in an existing file and alter it?

I do not have access to these controls and need the info to tell me how to do so... please and thank you.

-Brain
Aim for the sucker holes.

brianc
08-29-2010, 04:19 PM
I do not have access to these controls and need the info to tell me how to do so

The RS design panel is context sensitive, meaning only the functions that make
sense/are valid at the moment are active.

When first starting a new rocket, only NC, BT, transition and sub assembly are
available. Fins can be attached to body tubes, so those buttons are activated when you
select a body tube on the left side component tree.

If working on an existing rocket, it will depend on how the fin set was originally defined
by the designer. AFAIK, you cannot switch from a standard fin set to a custom
fin set. The standard fins need to deleted, then re-added as custom.

nukemmcssret
09-27-2010, 08:47 PM
OK, I'm trying to learn RockSim so that I might become a fully-fledged member of the rocket design process around here, and I am interested in NOT doing the ordinary. How does one:

1) Create something like a tube fin with any particularities I need (see the 'Dead Ringer' post in the Designer's Studio section); and

2) How does one create a set of attached fins perpendicular to a set of normal fins? Again, see the relevant post...

Thank you.

-Brain
Aim for the sucker holes.


Try using the pod feature for things you want to attach to the rocket. It takes a little playing around but it works. Especially for the perpendicular fins.
Let me know if it works for you. Cheers. nukemmcssret