Any Interest in a quick-check rocket calculator?

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Off Grid Gecko

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So, as I've said once or twice, I'm working on a new rocket simulator project. In the process, I've stumbled across something that I consider pretty handy, and if there is any interest, I'm happy to share it with you guys.
2020-05-09.png

After I finished the basic components for the 3D rocket builder, I wanted to get started on the flight model for the program. While it is limited in some respects at the moment (it doesn't use the motor end weight at all for the moment, for instance), the testing platform that I made has become something of a useful program on its own. At some point in the future, this node will gather data from the 3d model and use that to plot out important flight data, but for now the two components are totally separate.
I don't know about you guys, but while designing a rocket, sometimes I just want to do some quick checks to get an idea about what kind of altitudes I'm looking at, or what kind of motor delay might be best suited. I use a spreadsheet, but this has now completely replaced it, in my eyes, and I'm thinking about exporting this as a stand-alone program.
If it looks cool and you'd like to give it a try, just post a reply and I'll upload the program somewhere with download links. I'll probably port it to Linux, Windows, and Mac, but if you have some other OS you'd like to try running it on (an android phone or something) I can get those files out to you for testing purposes. If there's enough interest in an app, I can look into maybe doing that once it's a bit more complete.
Sorry, but the SI units are fixed for the moment. Custom units is a component that I'm leaving to tackle later for the main program.
For that, if you want a peek at the construction part of the simulator, check this out:
2020-05-03.png

pretty groovy right? Still needs tons of work as the functionality isn't all there yet and the models have some ugly bits on their inside parts (which will become a problem pretty soon) but I'm making progress. And there's a ton of code cleanup that I still need to do. Will be a long time on this part, but thought it might pique some interest as well. As I said though, this isn't going to be part of the calculator, but the calculator is allowing me to toy with the simulation model independently to get some statistics right and then I can close gaps once the two are combined.
 

Funkworks

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So the numbers are calculated and displayed in real-time while the user is tweeting component parameters? Yeah, why not! I don't make promises but I'm always downloading free techy stuff anyways and I bet other people do to.
 

Off Grid Gecko

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So the numbers are calculated and displayed in real-time while the user is tweeting component parameters? Yeah, why not! I don't make promises but I'm always downloading free techy stuff anyways and I bet other people do to.
The component side won't be with it for now. It takes longer to render the nose cone than it does to run the sim at the moment, though. It's pretty fast. I guess I could try that as an option at some point though, depending on how resource hungry the rest of the program gets for features. There would have to be a motor selection made before it can run though. I'll have to think about that for the end product, it's a cool idea.
The flight check program is just something helpful to me because I'd rather toy with weights and diameters in concept to get an idea of my flight envelope before I start laying out fin designs and internal components. Kinda like brainstorming a rocket.

EDIT: I may have misunderstood your comment. You have to hit that big launch button once you change the parameters...for now. I can maybe change that around like I did for the builder section which doesn't require a button. The calculation is really fast on my laptop though, tiny fraction of a second.
 
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BEC

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There used to be an iOS app called RocketCalc that did this sort of thing. It was VERY handy to use at the field to decide what delay to drill on a CTI motor. But it went away when iOS stopped supporting 32 bit apps and it would be lovely to have something like that again.

added: well, what do you know, something like that has returned to the app store. This new one is also called RocketCalc but isn't nearly as complete as the prior app by that name, which included motor data one could just select.
 

Off Grid Gecko

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There used to be an iOS app called RocketCalc that did this sort of thing. It was VERY handy to use at the field to decide what delay to drill on a CTI motor. But it went away when iOS stopped supporting 32 bit apps and it would be lovely to have something like that again.

added: well, what do you know, something like that has returned to the app store. This new one is also called RocketCalc but isn't nearly as complete as the prior app by that name, which included motor data one could just select.
I'm hoping to incorporate some motor data before moving on to the next function of the grander vision. I wonder if iOS or Android support loading motor files separately, as I was hoping to have some kind of import option to make getting new motor updates as separate files rather than needing to recompile a new program version.
In any case, iOS is a bit tricky because of the way their distribution is set up. I'd like to get this in there as an app, but can't spring for the developer fee at the moment, too many things around the homestead that need tackled first. Maybe I can find a work-around.

I didn't get time to work on this today, but maybe by the end of the week I can set up a link page on one of my websites and polish up the code a little better. There might be an update later on as well if I decide to incorporate Mach effects, but I have a feeling that will require examining the model. Maybe not.
 

BEC

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Fair enough. I know that Apple makes it a little more complicated for developers in order to make it less complicated on users (or, at least that's the intent).

I am not a software developer, and I have no sense of whether one could download from Thrustcurve (or wherever) to get motor data into an iOS app.
 

JohnCoker

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I'm hoping to incorporate some motor data before moving on to the next function of the grander vision. I wonder if iOS or Android support loading motor files separately, as I was hoping to have some kind of import option to make getting new motor updates as separate files rather than needing to recompile a new program version.
ThrustCurve.org supports an API so that you can search and download data files automatically.
 

neil_w

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That looks cool, although I personally would have no immediate need for it.

One piece of feedback: please don't use red text on a dark grey background. There is very little luminance contrast between foreground and background, which makes it eyestrain-inducing.
 

Off Grid Gecko

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Thanks John. I hadn't looked into it yet but I assumed they had some usable information past their simple graphs that show up on numerous websites. That'll make it easier to "bundle" some rocket motors in future packages.

That looks cool, although I personally would have no immediate need for it.

One piece of feedback: please don't use red text on a dark grey background. There is very little luminance contrast between foreground and background, which makes it eyestrain-inducing.
Thanks for the note. I thought that might be a problem for some. I tend to favor red on black simply because it doesn't bother my night vision. Used to be an astronomy thing but now days I stumble around quite often in the dark. Moonlit nights are pretty nice.
I could fiddle with the colors easily before I port everything out. Might just make it all white.
 

Off Grid Gecko

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Alrighty, rough test done for Windows (through WINE) and Linux .x86_64. Someone will need to tell me if it doesn't work on Mac. I don't have time to upload it tonight, but will try tomorrow after I find or create and icon for it. Got the motor burn functionality working so it will be a tad more accurate, even if the thrust curve isn't exact or even ideal, at least it accounts for Delta V from a change in mass. Should be quite accurate for most rockets I think, you guys will need to let me know if it's far off from your other simulations (and whether that's on the right or wrong side of the actual flight, lol). I'm hoping to upload this to my publishing website tomorrow and make a simple download page for it, but we'll see with work and everything else. Here's a snapshot with the new colors and the final layout. I'm calling this version 0.5 as I may add some features to it or fill it out with error checking later on to make it more robust.
Flight Check 2020-05-11.png
 

Off Grid Gecko

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Okie dokie, maybe not the best solution in the world but my internet out here lately has been the suck. Took hours to upload these little files to the server and I don't want to revamp the website just yet to accomodate software better. This is the page with the download links:
https://www.geckoprintpublishing.com/ourbooks.php
I have it listed for windows(64 bit), Mac, and two linux links: x86 and x86_64. I don't think I need to explain to linux people what the difference is. When you click your computer type, you should get a popup that asks if you want to save or run the file, as per normal download stuff.
That's prolly where it will sit for now until I can reserve some time to make a dedicated page for it and put some more relevant information. Till then, I'm back to work on the core software for writing my fully developed simulator.
Let me know if there are any problems. If a 32-bit windows version is needed, I think I can mix one up, but I'm pretty sure Windows is all 64-bit by now.
 

Off Grid Gecko

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Okay. i owe everyone a big apology. There was an error in one of my equations when I posted the program. I didn't notice it at first because I was flight checking data for a rocket that weighs close to 1kg.
When I put in the numbers for one of my lighter LPR rockets, I got some weird results, then woke up this morning and remembered something that I always forget when I make a rocket spreadsheet. Sure enough, that was the problem. I've replaced the files on the website so they should all be updated now and work properly. Feel free to re-download if you found the data values fishy. Same location (in the previous post).
The version when you run the program should say 0.5.2, if it doesn't then there was a problem with the upload, and please let me know, or any other problems.
Be sure to include your operating system if you are having trouble as well, as it might be specific to that export.
 
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