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OpenRocket Motor List is Outdated

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ZuluLima

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Some gripes about the motor files used in OpenRocket:

Redundant motors, eg. "Aerotech G71R"and "Aerotech G71-R" sometimes with different details but no notes to differentiate.

Too many options that aren't produced any more, eg. Aerotech G25. This was my perfect-fit choice that I was going to optimize around... until I went to check prices and discovered it hadn't been made in over a decade and a half. Also applies to some delay options on production motors, eg. Aerotech G77R-17.

Adding new-to-market motors seems to happen occasionally, but why has no one deleted the motors that are no longer produced? I might cull the 29mm options myself, but going over the whole list of thousands isn't happening. Do any of you have an updated list you are using, or perhaps a website that keeps current? Simply deleting files that don't appear on such a list would be simple, if a bit time consuming. Eliminating manufacturers that are out of business is a good start, so we could all uncheck those boxes. For instance, Roadrunner Rocketry is no longer extant.

I know OpenRocket is free and open source, so I would like to stop complaining and start contributing to the database if there is an effective way to go about it. Ideas?
 

Voyager1

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You could possibly get manufacturer‘s motor data from ThrustCurve, or download the motor files from each manufacture’s website. Some appear to have Rocksim (rse) files available that can be downloaded.
 

neil_w

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OpenRocket imports its data from Thrustcurveorg... but because the current release is old the motors are indeed out of date. The new release will have an updated list.

Yes, in the meantime it is annoying.
 

ZuluLima

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You could possibly get manufacturer‘s motor data from ThrustCurve, or download the motor files from each manufacture’s website. Some appear to have Rocksim (rse) files available that can be downloaded.
That's an interesting idea. Purge the old database completely and import only active motor files. I might have to give that a try, especially if the manufacturers have .ork files available as a batch.
 

heada

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You can also only import those manufacturers that you buy. For example, I don't have any Contrail hardware so why import Contrail motors?
 

rharshberger

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Thrustcurve just added some new .eng and .rasp files for updating the manufacturers motor lists. It easy to do, download the file, put it in a folder, use the add motor files tool in preferences(iirc) to specify the location ofcthe new file and repeat for each file. Restart OR and done, the files from Thrustcurve are by manufacturer, example thr AT file contains all current AT motors that are still certified.
 

Banzai88

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ETA: Apologies for the wall of text, but I've been struggling with this issue for a while. Well, more like I've moved into 'acceptance' since I found the great big "I BELIEVE" button and just moved on.......

I've been using OR for 5 years now, and I try to stay on top of the new motors and motor files like a religion.

The trouble is that no matter how many times you "Download and update" the motor files, what everyone is having issue with is the duplicate listings because of different naming protocol (among other things, see below) not only between the different updates lists, but within each file as well that creates duplicate listings.

The check box "Hide very similar thrust curves" only works IF the thrust curves are 'similar'.....which in the duplicate files, they often are very much not similar. YES, we all know that +/- 10%ish in performance....but sometimes the curves are WILDLY different....

I'll just pick two quick example that I plucked out just now, AeroTech E16 ALSO has a listing for AeroTech E16W.....same motor (with a different enough thrust curve that the "Hide similar...." button doesn't work), slightly different data in the motor file.
Another is the G79/G79W.....same motor, slightly different data.....the AT and CTI motor files are FULL of duplicates, with several instances in the L1 and L2 motor range where there are triplicates (look at the information in the "Show Details" tab of the "Select a Rocket Motor" pop up, you'll see that most of the dupes/trips are nearly the same data.

One of the spotting features is that the TYPE column will list "UNKNOWN" instead of Single Use or Reloadable.......but that doesn't always work, since many of the UNKNOWN files match the manufacturers data, especially for important things like Launch Mass, Empty Mass, Total Impulse, etc..... (yes, I've spent a LOT of time looking at what I can see in OR), BUT have a different thrust curve from the TRA file (which WILL match the manufacturers web site). What to do?

And YES, this occurs even if you check the box that says "Hide very similar thrust curves", which I'm not sure actually does much since I have no idea how the program defines 'similar' as similar enough to only show one listing.

Some motor listings with dupes (ALL have slightly different thrust curves, some WILDLY different, which matters somewhat) are listed as created by ThrustCurveTool and others are listed as coming from TRA or NAR certification test data (hand entered?), and without looking up the information and doing a thorough research of the information, it's a crap shoot which one is correct.
Often, looking at BOTH side by side, they BOTH are AFU as per manufacturer listings. One might have the right thrust and total impulse info, but the wrong launch and empty mass, the right mass number file will have some different thrust curve and impulse numbers..........and there is no pattern that I can detect in which to believe.

That (what I call a basic data disparity) happens between a LOT of the duplicate files, no matter the source (resident upon download or "update" files).

I wish that I knew how to edit the file, I would surely throw some volunteer time at it.

So I guess it boils down to several questions:

1. How do you make the data 'visible' to normal humans (normal humans being computer users NOT well versed in seeing behind the curtain where the magic happens)?
1a. Can that data be easily audited and edited?

2. What 'source' should be used for the 'official' motor data file?
2a. How do you resolve conflicts between TRA/NAR certification data and manufacturer listed data, including thrust curve?

3. Is there a conventional motor listing/naming protocol that ALL the existing data files can be compared to and edited to match?
 
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heada

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I agree that duplicate data needs to be purged but in some cases, it isn't duplicate data. Using your AT G79 example, there are actually 3 valid AT G79 motors that I can find. A LMS SU version, a standard SU version and a reload in the 29/120 case. I thought there might have been a 4th in the 29/40-120 case but my 13 seconds of looking didn't find it. All 3 of these are certified and even though they use the same name, they're treated as different motors due to their configuration.
 

Banzai88

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I agree that duplicate data needs to be purged but in some cases, it isn't duplicate data. Using your AT G79 example, there are actually 3 valid AT G79 motors that I can find. A LMS SU version, a standard SU version and a reload in the 29/120 case. I thought there might have been a 4th in the 29/40-120 case but my 13 seconds of looking didn't find it. All 3 of these are certified and even though they use the same name, they're treated as different motors due to their configuration.
OK, valid catch. I'm not used to working down that low in general in the smaller AT motors. Thank you for pointing that out.

Doesn't change the fact that there are dozens of other examples of what I pointed out that are NOT the case that you pointed out.

Would also be nice to have a way to mark/sort 'active' vs. 'legacy' motor production.
 

heada

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OK, valid catch. I'm not used to working down that low in general in the smaller AT motors. Thank you for pointing that out.

Doesn't change the fact that there are dozens of other examples of what I pointed out that are NOT the case that you pointed out.

Would also be nice to have a way to mark/sort 'active' vs. 'legacy' motor production.
I agree. Its hard to get unique names for motors in the G and below ranges due to the large number of motors and the limited amount of names they can use since the ranges are so narrow. The G79 you used stood out to me simply because I have 2 of the 3 types in my motor box right now and updated my inventory list a few days ago.

It would take a small amount of effort to go through the list and purge duplicates and update the status for legacy motors but then how is that kept up to date long-term? We can't rely on the manufacturers to always give us updates. I believe some of that work has been done because when you go to the search page on Thrustcurve, there is an option to search for regular, available or all.
 

ZuluLima

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I agree that duplicate data needs to be purged but in some cases, it isn't duplicate data. Using your AT G79 example, there are actually 3 valid AT G79 motors that I can find. A LMS SU version, a standard SU version and a reload in the 29/120 case. I thought there might have been a 4th in the 29/40-120 case but my 13 seconds of looking didn't find it. All 3 of these are certified and even though they use the same name, they're treated as different motors due to their configuration.
This just brings up a greater issue, which is that the program isn't necessarily built for ease/utility of motor selection. There need to be more checkboxes, columns, and ways to filter. My top request would be for a reload/single use filter.
 

RocketTree

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Some gripes about the motor files used in OpenRocket:

Redundant motors, eg. "Aerotech G71R"and "Aerotech G71-R" sometimes with different details but no notes to differentiate.

Too many options that aren't produced any more, eg. Aerotech G25. This was my perfect-fit choice that I was going to optimize around... until I went to check prices and discovered it hadn't been made in over a decade and a half. Also applies to some delay options on production motors, eg. Aerotech G77R-17.

Adding new-to-market motors seems to happen occasionally, but why has no one deleted the motors that are no longer produced?
Many of us have old motors on hand, so good to have it all. Sometimes a motor will return after years of unavailability. Other countries outside USA, do not have the same selection.

I thought there was a way to edit the list, but that might be RockSim Im thinking of.
Maybe this would help with the motor list.

I haven't tried it, but would like to add a couple motors to the list that are missing. I think its the E12...

Looks like you can get a G25 https://www.apogeerockets.com/Rocke...0_Motors/Aerotech_29mm_Propellant_Kit_G25W-10
 
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NateB

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Adding motors to Open Rocket is easy. As I said above, I just wish there was a check box with the option to only use user defined thrust curves and hide the bundled list.
 

Voyager1

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I haven't tried it, but would like to add a couple motors to the list that are missing. I think its the E12...
There’s probably a good reason the E12 is missing, assuming that you’re referring to the Estes BP E12. My experience with them has been anything but positive and I wouldn’t bother having them in the motor database.

I define my own motor database and have OR access that. I mostly use Aerotech and Contrail motors, with the odd Estes BP or composite.
 

manixFan

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Interesting thread! Following the link in post #15 leads to a post from 2012 on how to edit the internal motor database in OpenRocket. Unfortunately, the current version seems to have the data encoded into the .SER format, which is not a plain text file. But, it looks like it will be possible to make a dummy internal motor database with only one motor (required or it seems the program may crash) that would then allow each user to add just the motors they use on a routine basis. It should even be possible to substitute the original one with the dummy one and then simply change the program preferences to point to the correct folder with the 'right' user defined thrust curves, so theoretically a user could switch between the regular database and their own, personal set of thrust curves.

Unfortunately to edit SER files requires a JAVA development environment, such as Eclipse. I'll try it out but unfortunately I won't have time for a while. If someone else wants to give it a shot, please let us know how it works.


Tony
 

Anthony Claiborne

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I built my own simulator (in Python) and use the datafiles from Thrustcurve, which by and large are remarkably reliable. I have found a few real life motors that behave significantly differently in flight from that which the current the Thrustcurve data would indicate in the model. By way of example, I have found the AT D-15 Thrustcurve data to predict a significantly (say around 18%) higher thrust performance than is borne out in flight. I am thinking that some of the engineering/composition for some engines has been changed and the TC data may be out-of-date for some engines.
 
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