GoFast Rocksim Issue

Antares JS

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Hello all, I downloaded the rocksim file for the GoFast from Rocketman's website, but when I try to run any simulations with it, it won't leave the pad. There is no reason a J315R can't get a 10-pound rocket off the pad, so something must be wrong with some setting somewhere, but I can't find it. Any help would be appreciated. File is attached. I am using RockSim 10.
 

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UhClem

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When I load this using Rocksim 7 I get several material database errors and when run there is an immediate numeric overflow. Something is wrong with one or more of the components. I see several with no material specified and most use a mass override. Which one is causing the problem I don't know but I looked at a few and one thing jumped out at me.

The main body tube has a mass override but the CG for the part is left at zero or at the front of the tube. This would obviously mess up the final CG by a lot even if the program didn't choke on it.

A good approach I think would be to edit every part to have a known material and kill all of the part level mass overrides. Or at least give them reasonable values.
 

Antares JS

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I don't get any material database errors, but reading your post made me realize that I checked the overall mass override, but didn't think to check the ones for the individual components. I'll take a look at that later this evening. I bet that's where the problem is. Other suggestions still welcome just in case that doesn't work.
 

H. Craig Miller

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The error is occurring because the fin set has no "Material" specified on the "General" tab. Select any material and the simulation will run. Because you can switch the material back to the null material setting after a material has been selected, the data file is likely corrupted.

On a different note, the data for the design has been poorly entered. The AV Bay Coupler and Drogue Parachute would never be nested under the motor mount tube. On the whole, the data that has been entered for the design needs to be cleaned up.

Here is a file that will run.
 

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Antares JS

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Really just comes down to me being boneheaded and not thinking to examine the settings of all the parts. Thanks a lot. I'll take a look later this evening; I'm sure there's some more work to be done to make the sim reasonably accurate.
 

TSMILLER

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The error is occurring because the fin set has no "Material" specified on the "General" tab. Select any material and the simulation will run. Because you can switch the material back to the null material setting after a material has been selected, the data file is likely corrupted.

On a different note, the data for the design has been poorly entered. The AV Bay Coupler and Drogue Parachute would never be nested under the motor mount tube. On the whole, the data that has been entered for the design needs to be cleaned up.

Here is a file that will run.
Thank you for this, I couldn’t get mine to launch either, and chalked it up to complete noob in the sim programs.
I’ll use your file and try a few sims this weekend.

I just tried it using your file. It ran just fine. Thanks for the effort and contribution!
 
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