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A plea to motor manufacturers for consistent and error free motor file collections

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Winston

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For your motor files, please fix their most common errors and inconsistencies I've found in Thrustcurve.org downloads, errors and inconsistencies that really mess up the motor selection presentation within simulation programs, then offer them in a zipped file as detailed below. The common errors and inconsistencies I've found:

Make sure all available motor delays for a given motor in both ENG and RSE file types are included and correct.

If both file types aren't available on Thrustcurve.org, create the missing type using EngEdit 9 for inclusion in your zipped file mentioned below.

In a motor's RSE file, be sure the motor TYPE is specified.

Make sure your company name or the abbreviation for your company name is exactly the same in all files for your motors.

Correct any other errors or missing information within each file.

CSI, please standardize the motor naming convention within your motor files to be the same as the one you use on your web site. This isn't your fault, of course, and has to do with the preferences of the much appreciated individuals who upload CSI motor files to Thrustcurve.org.

Then, with those nice, clean, consistent and error free motor files:

Create a file name dated zip file with both the ENG and RSE files only for the motors you currently offer for sale and make it available for download. Why only the ones you currently offer for sale? So that we can select a motor from a list of motors that are actually available. The owners of OOP motors can just go to Thrustcurve.org and download the motor file(s) for their OOP motor(s); no need to have those OOP motors polluting everyone else's motor choices within the sim.

Please do not offer a zip file containing all of your motors in a merged *.eng file without also providing a merged *.rse file. Why? Because the by far most popular simulation programs can use RSE files which, unlike ENG files, contain the very useful piece of information about motor type (single use/reloadable).

Also, if you don't make certain that all common errors and inconsistencies mentioned above are corrected (but why didn't you?) in your motor files, individual rather than merged *.eng and *.rse files would be preferable so we can correct the individual files ourselves using EngEdit 9.

-----

CSI offers a current zip file with merged ENG and RSE files, but I haven't checked whether they are free of the common errors and inconsistencies listed above and only for motors they currently sell.

Aerotech offers a current zip file with merged ENG, but not RSE files, but I haven't checked whether they are free of the common errors and inconsistencies and only for motors they currently sell.

Estes provides nothing that I can find.

-----

To any individuals who might already have the above products due to their own efforts, please don't offer a download link unless you are willing to make the commitment that your product will be properly updated indefinitely. It's up to the manufacturers to have one of their employees spend an hour or two to do this and, later, much smaller amounts of time maintaining their file as new motors are offered and old motors are discontinued.

The individuals gracious enough to create and upload those files for your motors to Thrustcurve.org have already done most of the work for you. Please do the rest so we all don't have to do the same individually in order to have neat and valid motor selections within our sims.
 

markkoelsch

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Winston, the files on Aerotech's, CTI's, and Loki's came from me.

The process is manual. Errors happen.

Frankly, it is easy to sit in the cheap seats and comment. You want to help- tell me where there are errors so I can fix them.

Unless you are willing to contribute in a minimal way you should not comment further.

I have a list of AT corrections I want to do as another TRF'er was kind enough to point them out. Let me see when can I get to them? I have a 50-60 hour a week job. I have a Wife, two kids, a dog, and a house. Found out today that my dog has lymphoma, and is not long for this world. Oh yes, I want to actually build and fly a few rockets so I can enjoy this hobby.

So, I am also going to say this- I have never taken a motor from any manufacturer for my efforts that have likely helped them sell a bunch of motors. I say this as I have been questioned/ accused of this before by folks.

So, in my spare time I will try to get the AT files corrected.

The Loki file should be good to go as Scott contacted me about a couple things after looking through the files. Scott can only post the ENG files currently due to a web issue.

Once I am done with the above, I will likely put forth a call for help parsing the CTI files for errors, as this is a lot of stuff to sort through.

Or I might just stop doing this entirely...
 

Onebadhawk

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Winston, the files on Aerotech's, CTI's, and Loki's came from me.

The process is manual. Errors happen.

Frankly, it is easy to sit in the cheap seats and comment. You want to help- tell me where there are errors so I can fix them.

Unless you are willing to contribute in a minimal way you should not comment further.

I have a list of AT corrections I want to do as another TRF'er was kind enough to point them out. Let me see when can I get to them? I have a 50-60 hour a week job. I have a Wife, two kids, a dog, and a house. Found out today that my dog has lymphoma, and is not long for this world. Oh yes, I want to actually build and fly a few rockets so I can enjoy this hobby.

So, I am also going to say this- I have never taken a motor from any manufacturer for my efforts that have likely helped them sell a bunch of motors. I say this as I have been questioned/ accused of this before by folks.

So, in my spare time I will try to get the AT files corrected.

The Loki file should be good to go as Scott contacted me about a couple things after looking through the files. Scott can only post the ENG files currently due to a web issue.

Once I am done with the above, I will likely put forth a call for help parsing the CTI files for errors, as this is a lot of stuff to sort through.

Or I might just stop doing this entirely...
Mark,
I can only speak for myself..
I have made great use of yours and John C's tireless efforts on ThrustCurve.org more times then I could ever even try to guess at...
I appreciate what you and John do in your spare time very much....
I thank you both very much......

Teddy
 

blackjack2564

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Thank you Mark...for ALL you do!

Mark has been in the "background" for years, donating his time & efforts, to our hobby in ways most don't even know exist. [obviously or this thread would not be here]

For him a labor of love, for most others...boring tedious...time consuming work.

Thanks for all you do. [the nasty paperwork] that makes things [simulators]run smoothly! Moderating & background Forum work [servers & internet] along with stuff I'm sure I don't even know about.:wink:

Cj
 

Buckeye

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I kinda see Winston's point, here. Why don't the motor makers create, distribute, and maintain the data files for their own products? You would think that they have a vested interest in publishing the most accurate information. Instead, it seems like this burden falls on the hobbyists, particularly a couple individuals only.

Long ago, I once deleted my entire RASAero engine file and replaced it with files I downloaded from Aerotech's website, thinking this was more "official." Big mistake. The raw Aerotech files had errors. The RASAero guys did the cleanup.
 
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dhbarr

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Mark,

How can I help?


Is there a bug or ticket queue somewhere? Spreadsheet or other list of reported issues?

I use this data all the time, & would love to give back even just a little.

-dh.

PS: explicitly -NOT- asking for one or more of these things to be created.
 

markkoelsch

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Right now, what I can use is this. If you find something wrong on Thrustcurve contact me with specifics. You can PM me here, or my email is on Thrustcurve.

If you are downloading my complete motor files from Rocketryfiles.com please shoot me a PM here with specifics.

For the moment, I want to
concentrate on the Aerotech files as I already have begun that.

This is not a small undertaking as there are a lot of Aerotech motors. Then a whole mess of CTI motors after that.

As to old versus current production. I believe Thrustcurve filters out motors that are no longer certified. A motor could be long out of production and still be certified. The files on rocketryfiles are complete. I want folks to see motors old and new. It is interesting to look at old motors sometimes- why do you think AT brought back the i65 or the G125? Because folks who had seen/flew them asked, and because some people saw the motor in a sim and went I want one of those.

I also point to the most complete Kosdon file ever that I created a couple years ago. I did that because I think Frank's motors were historically significant to the hobby. Frank was not a computer guy so the files did not exist for the most part. I had to work that with Paul Holmes and Jim Rosson to gather everything I could. Why? Because I thought it important enough and of enough interest that someone do it.
 

DavidMcCann

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So winston wants a ton of work, done for free, and promises of updates forever.



Look.... I'll sum it up..(edited out) Don't be a jerk.


Mark- THANK YOU. your work is invaluable. Any minor glitches I've seen, have been insignificant.
 
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JohnCoker

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I would actually prefer to see data come from the certification organizations than the manufacturers.
 

cbrarick

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I'm just glad that we have Mark. Let's all be happy for that.
 

AlphaHybrids

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Motors for nothing and files for free?!? As David said, don't be a pud.

I can tell you don't even appreciate the amount of work Mark puts in for FREE.

Mark - I appreciate all your hard work keeping us flying.

Edward
 

AlfaBrewer

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I didn't read Winston's post as directed at Mark or John, but at AT, CTI, Loki, Estes, etc. It's in their interest to have complete and accurate information available.

To Mark and John, as others have said, THANK YOU for everything you do.
 

Bat-mite

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Mark, tremendous THANK YOU.

For everyone jumping on Winston, his plea is to motor manufacturers. Obviously, he assumed the files were coming from paid professionals and was unaware that an individual volunteer was doing the work. Maybe we can lighten up?
 

rstaff3

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Ditto here, we all owe a lot to Mark. I refer to Thrustcurve all the time.
 

Onebadhawk

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Mark, tremendous THANK YOU.

For everyone jumping on Winston, his plea is to motor manufacturers. Obviously, he assumed the files were coming from paid professionals and was unaware that an individual volunteer was doing the work. Maybe we can lighten up?
+1...
There was no malice in the original post....
No need for negativity pointed anywhere...
Just a great debt of gratitude for Mark K and John C....

Teddy
 

markkoelsch

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Gents, I thank you for me, and while I cannot speak for John I am sure he appreciates the comments as well.

I admit to likely being a bit irritated last night.

I have been very busy. What I will try to do soon though is put forth a plan on working the files for errors. I might ask for a few people to assist as it is a lot of stuff to work through.
 

Winston

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Winston, the files on Aerotech's, CTI's, and Loki's came from me.

The process is manual. Errors happen.

Frankly, it is easy to sit in the cheap seats and comment. You want to help- tell me where there are errors so I can fix them.

Unless you are willing to contribute in a minimal way you should not comment further.

I have a list of AT corrections I want to do as another TRF'er was kind enough to point them out. Let me see when can I get to them? I have a 50-60 hour a week job. I have a Wife, two kids, a dog, and a house. Found out today that my dog has lymphoma, and is not long for this world. Oh yes, I want to actually build and fly a few rockets so I can enjoy this hobby.

So, I am also going to say this- I have never taken a motor from any manufacturer for my efforts that have likely helped them sell a bunch of motors. I say this as I have been questioned/ accused of this before by folks.

So, in my spare time I will try to get the AT files corrected.

The Loki file should be good to go as Scott contacted me about a couple things after looking through the files. Scott can only post the ENG files currently due to a web issue.

Once I am done with the above, I will likely put forth a call for help parsing the CTI files for errors, as this is a lot of stuff to sort through.

Or I might just stop doing this entirely...
Did I not make the point to thank those who created the motor files and uploaded them voluntarily? I am not griping about your files and your much appreciated efforts.

My point is that it would be nice to have those who profit from selling us motors do more than just compile a bunch of files created by others and, instead, spend the time to go through those files ONCE to correct any errors or inconsistencies within the files for THEIR motors and then, with much less effort required, maintain those files into the future. Who is more qualified to correct any errors for THEIR motors than THEM? And, frankly, once again being very grateful for YOUR efforts, why shouldn't THE MANUFACTURERS be the ones responsible for making the motor files for THEIR motors in the first place?

What brought this all on is this recent post in the suggestions for Rocksim improvements thread which I agreed with wholeheartedly:

A more "powerful" or "insightful" engine import/management feature. My engine library is a mess for CTI, Cessaroni, Cessaroni Technologies, etc. I think I have imported things incorrectly, maybe. I have a lot of what appears to be duplications...

Note how he mentioned an issue caused by inconsistent manufacturer naming within the motor files. That inspired my idea that manufacturers should expand upon what people like you have already so graciously done voluntarily, having already done the vast majority of the work for them, and make the checks I mentioned above, compile a folder of only the motors they currently sell, once again something THEY would know best, and merge it into ENG and RSE files.

So, once again, THANK YOU for your 99% perfect efforts, but it shouldn't be up to YOU or anyone other than those who profit from the manufacture and sale of motors to do that last 1%.
 

Winston

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Mark, tremendous THANK YOU.

For everyone jumping on Winston, his plea is to motor manufacturers. Obviously, he assumed the files were coming from paid professionals and was unaware that an individual volunteer was doing the work. Maybe we can lighten up?
I was afraid the tone of my message might be misinterpreted and it was. And you are correct, the message was about my beef with manufacturers who get away with compiling the work of others while putting no additional effort whatsoever into it, instead just leaving all the work to be done by volunteers. I know this isn't a huge industry, but come on!
 

bobkrech

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Thanks Mark, you do a great service for the community.

Winston.

The motor certification data obtained from NAR S&T, TRA TMT and CAR MTC represents the actual performance of off-the-shelf motors that everyone can purchase, and not from data obtained from special or prototype motors produced by the manufacturers.
 

DavidMcCann

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Having the manufactures write the data files would be like having Chevy and ford write the consumer reports on their own trucks.
 

Buckeye

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I would actually prefer to see data come from the certification organizations than the manufacturers.
Not a bad idea. It would be nice to have one, official, "correct" dataset per motor provided by the "owner" (either OEM or S&T). This way, Thrustcurve can have one entry for the G80, instead of five. Less work for you.
 

Buckeye

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The motor certification data obtained from NAR S&T, TRA TMT and CAR MTC represents the actual performance of off-the-shelf motors that everyone can purchase, and not from data obtained from special or prototype motors produced by the manufacturers.
How does one find the cert data? How are eng files distributed to the software makers and database keepers? I made a cursory look at websites:

NAR: Some datasheets provided with printed thrust curve points and graphs. No digital files, like eng or rse.

TRA: Nothing

CAR: The most organized website. Printed thrust curve graphs. No digital files, like eng or rse.
 

markkoelsch

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I have made most motor files from the cert data. From TMT, Paul Holmes will send me the actual test stand data. I have used the cert documents from CAR and NAR versus raw data. Either of those work well.

I have some thoughts on all of this, and will share after I have a bit of a chance to work through it.
 

mikec

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FWIW: When AT released a batch of SU motors back in 2014, I captured the thrust curves they gave using TCTracer and uploaded the resulting RASP files to thrustcurve. It took an hour or so all told and I was happy to do it. In most cases, those are the only files for those motors on thrustcurve at this point (see, e.g., K535) and as far as I know they're fine.

Is every file on thrustcurve perfect and consistent? No. Remember that a lot of the motors were certified before thrustcurve and Rocksim even existed. Could the vendors or the certifying orgs streamline the process? Sure, but it would save a few hours of simple volunteer labor. I'd rather have the vendors working on designing new motors and producing their existing ones.

I agree that it might help if we tossed all of the old and redundant files and made a clean ZIP file containing every motor. I did something like this a few years ago for the Palm simulator pRASP for just AT and CTI motors, and the hardest part, as I recall, was weeding out the motors that used the CTI naming convention with the total impulse in front of the letter (it's a good idea in principle but too hard to remember in practice, IMHO.) That file used to be on RP and I think was being served somewhere still; I could probably find it in my backups if needed. [found it, https://www.rocketryfiles.com/files/FlightSimulation/pRASPmot.zip -- one giant rasp.eng file with every motor I could find at that time.]

As for RSE files, I don't use Rocksim and TCTracer doesn't produce RSE files; I'd say that one's on Apogee, it's their format, and Rocksim can use RASP files directly anyway, I believe.

And thanks again to John and Mark for all their work!
 
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bobkrech

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How does one find the cert data? How are eng files distributed to the software makers and database keepers? I made a cursory look at websites:

NAR: Some datasheets provided with printed thrust curve points and graphs. No digital files, like eng or rse.

TRA: Nothing

CAR: The most organized website. Printed thrust curve graphs. No digital files, like eng or rse.
Here is a typical NAR certification report as shown in paperwork for the AT 38 mm I218R https://www.nar.org/SandT/pdf/Aerotech/I218.pdf

Page 1 provides the official averaged parameters obtained by S&T during certification testing.

Page 2 provides the statistics obtained during the certification testing.

Page 3 contains the .eng file for the most typical motor obtained during the certification. Simply copy and paste it into your .eng file library.


Remember that your motor may vary from the certification data. Note that for these 9 motors submitted for certification, the total impulse had a standard deviation of 0.3%, the average thrust had a standard deviation of 1.8% and the burn time had a standard deviation of 1.5%. The allowable variation is specified in the motor testing manual. https://www.nar.org/wp-content/uploads/2014/08/ST-MotorTestingManual.pdf
 
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