New Rocketry App for iPhone and iPod Touch

[Andreas Müller]

You cannot see terms and conditions? Have you ever looked before you posted this? Just click here to view it.

Well, I stand corrected. I would never have expected the terms under "help", though, that's probably the only place I didn't look.

... a forum like yours being in the web for just 3 years or so...

Correction: I have no forum.

 

[cwbullet]

Nice attempt, but to be honest, the imperial units are not complete enough. I tried it out and it used 1/2 imperial and 1/2 metric when set to use imperial only.

 

[Andreas Müller]

Nice attempt, but to be honest, the imperial units are not complete enough. I tried it out and it used 1/2 imperial and 1/2 metric when set to use imperial only.

There was some discussion with the requestors of the imperial units feature back when it was added about which units should be imperial, and which metric. E.g. motor mount diameters are never imperial, imperial wouldn't make sense, as motor manufacturers specify motor diameters in metric only, and some even name their product lines after the metric diameter (RMS-38, Pro38). That discussion mostly covered the Rocket and Trajectory subapplications. What was implemented is the result of that discussion. As a consequence, it is possible that some less discussed parts do not use the units an "imperial" person would expect. I'm a "metric" person, all those imperial units look equally strange to me, I have no clue where to use inches and where feet. And even in the well discussed parts, some users may disagree about unit choices. So if you disagree with some of the choices, or have found an outright omission, please be more specific so that we can change it in the next release (version 1.4, free upgrade planned for march, containing italian and french localizations, rocket templates and scaling feature). Technically, there is no problem displaying any system of units: The app contains a whole unit conversion layer between the models (they implement the physics and are always metric) and the views you see on the screen. But that layer only does what it is told to do...

 

[Andreas Müller]

Hi Chuck,

Nice attempt, but to be honest, the imperial units are not complete enough. I tried it out and it used 1/2 imperial and 1/2 metric when set to use imperial only.

Today I went through iPowerrocket screen for screen chasing down places where non-imperial units were used. The only values that are displayed in metric units are

1. Forces are displayed in Newtons. The alternative would be pounds, but that's not a unit of force
2. Impulse in Ns, which is what everybody uses: manufacturers in their product docs (e.g. AT, in its high power reloads, does not even mention the equivalent value in lb-sec, just N-sec), TMT certification documents, the safety code.
3. Times, there is no different imperial unit of time.
4. Motor diameters in mm: the motor and kit manufacturers also use mm, so talking about 3.9" motors would probably more confusing than it would help.
5. The size of the the ejection charge in g, this also seems to be what people are using. E.g. see https://www.vernk.com/EjectionChargeSizing.htm

So I really don't see how you get at "1/2 metric". The only item we could discuss is the thrust. So let me sollicit your opinion: Do imperial users want to see the thrust in pounds?

Andreas

 

[SAC of MMMSClub]

Andreas,

For me personally, I do not need Thrust in pounds, Newtons is fine. Having correct motor data is the most important thing.

Metric is ok too, my phone has a conversion function.

Will your app work on other platforms i.e. Android or others(forgive my lack of knowledge on apps and phones I'm OLD) as I am looking for a new phone?

Have all the bugs been worked out, as there were some sour reviews?

Thank You,

Scott
NAR#91379 L0

 

[troj]

Do imperial users want to see the thrust in pounds?

No. We're used to seeing it in Newtons, so having it in pounds would be odd for us.

-Kevin

 

[Andreas Müller]

Will your app work on other platforms i.e. Android or others

Android is an option I'm considering. Unfortunately I cannot do it myself, so I hope to find a student at my university who could do the port as a semester or bachelor thesis. One young rocketeer in our club (ARGOS, the swiss TRA prefecture) happens to be a student at my university, so he would have the necessary rocketry background. He also is a very good student (got a straight A in my rather tough course on the theory of computation), unfortunately he also has lots of other ideas that he could do as thesis projects. But I'm working on it....

Other platforms:

• Symbian has just died (well, it will survive for some time, but will hardly get new developers)
• WebOS: is there really a market?
• Windows Phone is not my world: I'm a Unix or Java person

BTW, we still test each release of iPowerrocket on iOS 3.1.3 on a first generation iPod touch, which means all iPhone OS devices, including the first generation iPod touch and the original iPhone can run iPowerrocket (3.1.3 is the last version supported in those devices). Also, since an iPod does not need a phone contract, it could be cheaper alternative.

 

[eggplant]

Android is an option I'm considering. Unfortunately I cannot do it myself, so I hope to find a student at my university who could do the port as a semester or bachelor thesis. One young rocketeer in our club (ARGOS, the swiss TRA prefecture) happens to be a student at my university, so he would have the necessary rocketry background. He also is a very good student (got a straight A in my rather tough course on the theory of computation), unfortunately he also has lots of other ideas that he could do as thesis projects. But I'm working on it....

Other platforms:

• Symbian has just died (well, it will survive for some time, but will hardly get new developers)
• WebOS: is there really a market?
• Windows Phone is not my world: I'm a Unix or Java person

BTW, we still test each release of iPowerrocket on iOS 3.1.3 on a first generation iPod touch, which means all iPhone OS devices, including the first generation iPod touch and the original iPhone can run iPowerrocket (3.1.3 is the last version supported in those devices). Also, since an iPod does not need a phone contract, it could be cheaper alternative.

I happen to be an android dev...

 

[Andreas Müller]

Have all the bugs been worked out, as there were some sour reviews?

1.3 fixes all known bugs. No new bugs have been discovered so far. There is currently just one report open that a certain motor sims much lower than on Rocksim. Usually the results are quite close, the differences can usually be attributed to differences in the Cd used. We are investigating whether the motor data for that motor may be incorrect (we pull motor files from vendor websites and convert them to a format that is easier to parse in the iOS software environment, we have seen some broken .eng files, and it is possible that this problem report cited could be such a case). Of course, if the motor data is faulty, we will publish a corrected version of the motor file, which 1.3 can update without the need to update the app.

 

[cwbullet]

I downloaded the new version and figured it out. I was incorrect on the units. Is it possible to add an way to also calculate papacute descent by ccd?

 

[Andreas Müller]

Is it possible to add an way to also calculate parachute descent by cd?

Do you mean the option to enter a custom Cd for the parachute calculator? The current implementation has two implicit values, borrowed from a book an parachute systems, selected when you select the parachute shape.

The problem is where to place that in the UI, screen area is so limited... Some implementation ideas:

1. I simple implementation would be to add a third shape "Cd", and add an option in the iPowerrocket settings where you can set the custom Cd to use. Changing the Cd would be awkward, however
2. In the seetings, one could add an option "Use implied Cd" under the title "Parachute". If this is turned off, then instead of the shape selection, you would get a slider to change the Cd. The problem is that you will loose the
   ability to use the shapes without leaving iPowerrocket to go to the settings
3. Tapping the "Shape:" label turns it to "Cd:", and the shape choice is replaced by a Cd slider. The disadvantage is that you normally don't expect any action when you tap on a label.

What do you prefer, or do you have other suggestions?

 

[Andreas Müller]

Ok, for the parachute Cd thing, I came up with the following solution, which will be in 1.4. In the corner on the upper right, you get a button that says "Cd". If you tap it, you'll get a slider to set the Cd instead of the two options X/Spherical. The approximate Cd values of X/Spherical shape parachutes are marked with appropriate icons, see the screenshot (of course, your english speaking iPhone will display it in english).

 

[dixontj93060]

Ok, for the parachute Cd thing, I came up with the following solution, which will be in 1.4. In the corner on the upper right, you get a button that says "Cd". If you tap it, you'll get a slider to set the Cd instead of the two options X/Spherical. The approximate Cd values of X/Spherical shape parachutes are marked with appropriate icons, see the screenshot (of course, your english speaking iPhone will display it in english).

Nice.

 

[Andreas Müller]

Lukas just uploaded version 1.4 of iPowerRocket to Apple, the app is now awaiting review. It offers the following new features:

- italian localization: there is a very active italian Tripoli prefecture, they have their big annual launch MIR (Meeting Italiano di Razzimodellismo) in two weeks, so 1.4 is just in time for their meeting.
- the parachute calculator can now accept arbitrary Cd values, not just the shapes cross and hemisphere (features suggested in this forum)
- transitions can now be ogives
- rockets can now be copied, scaled and renamed
- a database of popular kits from Estes, Aerotech, PML and LOC simplifies simulating rockets built from these kits: just copy the kit, give it a name, add mass and Cg, and start simulating.
- the database also contains 10 templates of rockets popular among scale rocketeers. If you want to build an Arcas in 6", just pick the Arcas template, give your rocket a name, e.g. 'Arcas 6"', select scale to 6" and tap 'done'. There's your Arcas ready for simulation.
- the rockets in the database also can have arbitrary polygonal shapes, but in this release, you cannot edit them yourself (yet).

For users of iPowerRocket, 1.4 is a free upgrade available as soon as Apple approves the app.

Furthermore: you'll find iPowerRocket on Facebook, just search for IPowerRocket.

 

[GregGleason]

Thanks for the update.

Greg

 

[Gus]

Good news, Lukas! Thanks for continuing to make this product even better.

 

[Andreas Müller]

iPowerrocket 1.4 has just been approved by Apple and can now be downloaded from the App Store. Have fun.

 

[Andreas Müller]

We have just finalized and uploaded version 1.5 of iPowerrocket. It fixes some minor bugs, and includes two new features:

1. a simplified method to rename a rocket

2. a subapplication to design ellipsoid parachutes. Enter the dimensions of the parachute in the application, and it will produce the sewing pattern as a PDF file. It also figures out how to optimally place the individual panels of the parachute on the cloth. Just print out the PDF, cut out the panels, sew the together, and get a perfectly shaped ellipsoid parachute. For an example of a large parachute using this design have a look at the 4.5m main chute of my Atlas Centaur, especially the opening at 5:20.

Unfortunately, PDF generation is a feature that only became available in iOS 3.2, it cannot be used on the oldest supported devices (3.1.3). And printing via AirPrint is even more recent, and requires a printer supporting AirPrint. But you can always send the PDF via Email, and print from your PC.

 

[Andreas Müller]

iPowerrocket version 1.5 has been approved by Apple and can now be downloaded from the App Store. Have fun!

 

[Andreas Müller]

We are currently preparing release 1.6 of iPowerrocket. It will include some great new features:

• Flight data import for the Louis Schreyer's Altimax altimeter
• Emailing, printing and opening PDF files in other apps (like iBooks): rocket plans, checklist, flight data and flight cards
• some bug fixes

More information about the data import feature in the article on the ipowerrocket website: https://ipowerrocket.othello.ch/index.php?option=com_content&view=article&id=12&Itemid=12.

If you have some whishes/bugreports that you would like to have included in 1.6, please send email to [email protected]

 

[Andreas Müller]

Lukas today has prepared release 1.6 and has uploaded it to Apple. As soon as it has passed the review process, it will be available as a free upgrade to current users.

 

[UPscaler]

request: Android :wink:



Braden

 

[Andreas Müller]

request: Android :wink:

As I explained in a post on the rocketry planet, you are requesting a complete rewrite of an application with over 27000 lines of code for a market that is way too small to ever pay for it and with no benefit to the existing user community, including it's developers. Find an Android Dev who is also a rocketeer and has too much spare time, or buy an iOS device :wink:

 

[BayouRat]

Has anyone tried the Android ap "Rocketry Tools" ?

https://www.androidzoom.com/android_applications/tools/rocketry-tools_bjlyx_screenshots.html

 

[Oliver]

No, but I´ve installed the Model Rocket Calculator on my Droid:

https://de.androidzoom.com/android_applications/tools/model-rocket-calculator_tqsc.html

But I guess it is a little bit offtopic here?

Oliver