OpenRocket vs. Rock Sim

[Weldo]

I am curious about the difference between the two and I couldn't find a thread dedicated to this.

I've used OpenRocket but I've no experience with Rock Sim.

So to you guys who have tried both, is Rock Sim worth the money? Does it give you capability that OpenRocket does not? Are the simulations different/better/more accurate?

 

[mikec]

In my experience OR is more accurate. RS has more functionality for pods and other complex configurations. I've never bought RS. There's a trial version you can play with if you want to compare.

There's tons of discussion about this.

 

[Weldo]

Oops. Sorry if it's a common topic. I didn't notice any thread titles about it.

 

[mikec]

Try searching for "openrocket rocksim": https://www.rocketryforum.com/threads/openrocket-vs-rocksim.49986/ https://www.rocketryforum.com/threads/best-sim-results-openrocket-or-rocksim.155883/ https://www.rocketryforum.com/threa...upersonic-speeds-openrocket-or-rocksim.70823/ and many many more.​

 

[Weldo]

Thanks.

 

[mikec]

No worries. Search function is confusing and people rarely post in the appropriate place on this forum so stuff can be hard to find.

 

[CoAz2k]

I'm an OR user, but RockSim v10 is due out any day, if the release is not delayed by COVID19. The Colorado governor just issued a "stay at home" order, which has closed Apogee's office.

 

[K'Tesh]

Can't help you with this one... never tried RS

 

[Weldo]

One thing I couldn't figure out how to do in OR is put a smaller body tube inside a larger body tube concentrically. I was working on a design like the Honest John and wanted a small tube running from nose cone to tail with a larger body tube on top of that with a transition at the rear.

I was able to do it by treating the inside tube as an "inner tube".



Notice the inner tube is red and the aft tube is blue. I tried just making the inner tube longer overall to the total I wanted but you cannot add fins to a piece labeled as an "Inner Tube"

It's just a little work around.

 

[Off Grid Gecko]

edit: oh, crap, nevermind I looked closer at your picture and this is similar (possibly exactly) what you did.. Can't find a delete button. I just got off work and I'm tired and sweaty.

My original post:
n- before we go way off topic, OP I think your solution there would be to do the transition piece and attach another tube below it, then add the inner tube inside the transition. This shouldn't affect the model mechanics so as long as the "skin" is the way you want it the sim will work, and it should still get your weights accurate. Don't worry that there's a break in the part on the sim, unless airflow is going through the middle you will be alright.

 

[neil_w]

It's just a little work around.

That is the Correct Way to Do It™.

 

[Weldo]

Haha thanks guys! I can hardly believe OR is a free program! It's so awesome to make designs and even run simulations for all kinds of wacky ideas.

Anyone know if it's possible to update the motor selection? This may be the one big failing of OR. I wanted to simulate some of the Quest Q-Jets (like the D16) but I don't think they are in the program.

 

[neil_w]

Anyone know if it's possible to update the motor selection?

Yes indeed. Open up preferences and look in the General tab:


Set up your path to where you want to store your own motor files (I do it on Dropbox so my motors are available on all machines I use to run OR.) Then drop in .eng or .rse files nabbed from thrustcurve.org. I have all the QuestJets in there.

Next OR release (whenever that is) will have an updated motor database, but you can do what you need today.

 

[Weldo]

Dude! Thank you for sharing that!

 

[Weldo]

I just added the Quest Q-Jet motors. I there a way to remove old obsolete motors from the list in OR? As near I can tell Quest is currently only making 4 different impulse motors, albeit with varying delays, but OR shows like 20. Can I pare this down for clarity?

 

[neil_w]

I just added the Quest Q-Jet motors. I there a way to remove old obsolete motors from the list in OR? As near I can tell Quest is currently only making 4 different impulse motors, albeit with varying delays, but OR shows like 20. Can I pare this down for clarity?

There's no straightforward way to do that, sorry. The whole collection of motors is embedded in the .jar file as a .ser file. If you want to go in there and try hacking it, be my guest.

 

[Weldo]

The whole collection of motors is embedded in the .jar file as a .ser file. If you want to go in there and try hacking it, be my guest.

Haha I don't even know what most of that means, so I'll have to decline!

It doesn't appear to be possible to select ONLY the motors you want to see. I mean you can limit the visible motors to a single manufacturer but you can't show/hide specific motors. I'm just curious because all of the stuff I model would have a very small number of possible motors.

 

[mikec]

I use thrustcurve.com to narrow down my motor selection, with OR you would have to build a new simulation for each possible motor and that's a pain.

 

[neil_w]

I use thrustcurve.com to narrow down my motor selection, with OR you would have to build a new simulation for each possible motor and that's a pain.

That is a good strategy.

 

[Buckeye]

I use thrustcurve.com to narrow down my motor selection, with OR you would have to build a new simulation for each possible motor and that's a pain.

Yes, that sucks. Check RockSim 10. The software is getting some updates including a batch motor run (finally).

I am gonna dust off my rkt files and start using more RockSim, as it is now back to life. OpenRocket has been stuck in neutral for 5 years.

 

[Buckeye]

The whole collection of motors is embedded in the .jar file as a .ser file.

Really? Rocksim and RASAeroII give the user easy access to the motor files. Seems like the logical thing to do. I don't know how you guys manage to work with the OR code...

 

[neil_w]

Really? Rocksim and RASAeroII give the user easy access to the motor files. Seems like the logical thing to do. I don't know how you guys manage to work with the OR code...

I admit I was surprised to see it done that way, this was the first time I looked at it. Definitely something to be improved in the future.

BTW the project is somewhat back to life, several people actively working now.