Rocksim Pro Results

[TJRotramel]

Hello. My name is TJ Rotramel and I am the Dynamics lead for the Brazoswood High School Goddard program. Our mission statement is to Design, build, and launch a rocket that achieves a successful flight, and to recover the rocket as well as engine data. For reference, we will be building a hybrid engine with 78,000 N*s of total impulse and we are reaching an apogee of around 50,000 ft.
Recently, I have had problems with Rocksim Pro. With higher impulse motors, Rocksim Pro is giving unbelievable numbers (see image for reference). Rocksim 10 and RASAero II run fine on this computer and give believable results. I have been through this specific rocket file and engine file many times and I’m curious if anyone has ever run into this problem.

 

[FredA]

Only trust RASAero II

 

[TJRotramel]

Only trust RASAero II

I am mainly concerned with descent. We have made wind tables, but rocksim pro is the only software that has them. RASAero is the way to go for the way up, but going down is what we’re uncertain about

 

[mbeels]

Hello TJ,

Did you check with Apogee? They're pretty good about responding to Rocksim issues.

 

[TJRotramel]

Hello TJ,

Did you check with Apogee? They're pretty good about responding to Rocksim issues.

Yes I have. They said they have no idea, but the problem is on my end.

 

[mbeels]

Yes I have. They said they have no idea, but the problem is on my end.

Huh! That's not helpful. Can you post the rocket file? Maybe someone looking through it can spot something.

 

[TJRotramel]

I will upload files soon

 

[Buckeye]

You might be on your own on this one. Not many people have RockSim Pro. Most of the cheapskates on this forum complain about the cost of regular RockSim!

Perhaps Apogee can't comment because they no longer sell RockSim Pro. Dunno.

I assume you want the recovery splash down pattern. That's pretty cool.

Since you have both RockSim (which is running fine) and Pro (which is not), you may have to simply scrutinize every input and output side by side to see where they diverge. Make use of the graphs to really understand the flight vs. time.

 

[TJRotramel]

You might be on your own on this one. Not many people have RockSim Pro. Most of the cheapskates on this forum complain about the cost of regular RockSim!

Perhaps Apogee can't comment because they no longer sell RockSim Pro. Dunno.

I assume you want the recovery splash down pattern. That's pretty cool.

Since you have both RockSim (which is running fine) and Pro (which is not), you may have to simply scrutinize every input and output side by side to see where they diverge. Make use of the graphs to really understand the flight vs. time.

Thank you so much. I will get to work on that!

 

[Apogee Components]

Post your rocket file and I will look over it and double check some simulations on my more recent version of pro. If Tim / Michelle told you the problem is on your end, I'm not sure I will have different results, but I am happy to give it a look.

 

[afadeev]

Yes I have. They said they have no idea, but the problem is on my end.

If Apogee's customer supports keeps insisting that their product's problem is on <your> end, then the solution is obvious:
- upgrade <your> end to OpenRocket: https://openrocket.info/

 

[kuririn]

Don't think that moving from Rocksim Pro to Openrocket is an upgrade.

 

[Apogee Components]

For the record, I'm working with him on this now.

However, know that it is unlikely this is an issue with RockSim Pro. He's doing a very large rocket, with a very large custom motor, and there are a whole lot of data entry points that could be causing this error. I have a few suspects, and I'm trying to work through them.

Regardless I'll update here when I have this resolved.

 

[Voyager1]

I am mainly concerned with descent. We have made wind tables, but rocksim pro is the only software that has them. RASAero is the way to go for the way up, but going down is what we’re uncertain about

Not so! Open Rocket has a multilevel wind addon that allows you to apply ascent and descent wind profiles to the simulation.

https://github.com/rocketsam2016/MultiLevelWind/releases/tag/latest
Also, if you wish to generate splash patterns of possible landing sites, then you could use the Cambridge Rocketry Simulator that uses the Open Rocket GUI.

https://sourceforge.net/projects/camrocsim/files/
In both, you just input the wind data at the various levels you require from the aviation wind forecasts.

 

[TJRotramel]

Not so! Open Rocket has a multilevel wind addon that allows you to apply ascent and descent wind profiles to the simulation.

https://github.com/rocketsam2016/MultiLevelWind/releases/tag/latest
Also, if you wish to generate splash patterns of possible landing sites, then you could use the Cambridge Rocketry Simulator that uses the Open Rocket GUI.

https://sourceforge.net/projects/camrocsim/files/
In both, you just input the wind data at the various levels you require from the aviation wind forecasts.

I have not worked with Open Rocket, but I will look into it. Apparently it is pretty popular and well liked. Thank you!

 

[TJRotramel]

Update: I figured out the problem
With engine edit, you can save two types of files, .rse and .eng. With Rocksim 10, we can use .rse files, but with rocksim pro, we have to use .eng files. An odd fix, but a fix nonetheless. Thanks everyone for your input!

 

[Tobor]

Update: I figured out the problem
With engine edit, you can save two types of files, .rse and .eng. With Rocksim 10, we can use .rse files, but with rocksim pro, we have to use .eng files. An odd fix, but a fix nonetheless. Thanks everyone for your input!

I'm glad you found a solution. Good luck with your project.