ThrustCurve.org Motor Guide app

JohnCoker said:

You can download your rockets saved on the web site if you enter your credentials (see Settings, Account page).

Click to expand...

Thanks, John. I was in a hurry...prepping for the Dairy Aire launch that was canceled...and didn't take the time to research it.

AFK for a minute....

Just signed in, gave my creds, and downloaded 27 rockets to my smartphone. Excellent!!

Now to learn the new interface.

John, I noticed in the App Store it shows a thrust curve graph. I never saw that on the test version and can't figure out how to see graph in new version. Any hints?

timbucktoo said:

John, I noticed in the App Store it shows a thrust curve graph. I never saw that on the test version and can't figure out how to see graph in new version. Any hints?

Click to expand...

When you hold the iPhone in portrait orientation, you see the data. When you hold the iPhone in landscape orientation, you can see the thrust curve.

Greg

GregGleason said:

When you hold the iPhone in portrait orientation, you see the data. When you hold the iPhone in landscape orientation, you can see the thrust curve.

Greg

Click to expand...

Thanks! All the time I had that test app, I never turned my phone once!

timbucktoo said:

Thanks! All the time I had that test app, I never turned my phone once!

Click to expand...

The other place orientation matters is in lists. In landscape orientation, the lists have extra columns.

John, been playing with it since first beta. Works really well. Took it to a launch a couple weeks ago and ran it against a couple different rockets. Really worked well. Another excellent resource you have provided the hobby!

John, thanks for the tip about changing the screen orientation to see the hidden columns (velocity, delay) after running the Motor Guide. Should have realized that when I first tried it.

For years I have carried a loose leaf binder containing all the ThrustCurve motor guide printouts for my various rockets to launches. Now my Android phone will serve that purpose. And I'll be able to modify the rocket data on the fly.

A very handy tool. Thank for the site and the app.

Thanks for the kind words.

Building a small-screen app was an interesting exercise. Normally, one can provide widgets that point to all features, but when real estate is a premium and every widget needs a large amount of space to be touchable, you can't. Of course, I'm also not a UI guy, which makes it even harder.

My hope was that people would be used to orientation changes showing different views from other apps. But if that's not obvious enough, maybe there is some way to indicate "more info over there". Has anyone seen a good way to hint that the user should rotate the phone for a different view?

JohnCoker said:

Thanks for the kind words.
Has anyone seen a good way to hint that the user should rotate the phone for a different view?

Click to expand...

Can you do a pop-up on that screen the first time a user ever accesses it? A user could dismiss it and never be bothered with it again. I eventually discovered that orientation would show the plot but it was more by accident than intentional.

VernK said:

Can you do a pop-up on that screen the first time a user ever accesses it?

Click to expand...

Possibly; let me think about it (it's on the to-do list now).

Had a play last night, very nice app thanks John. I had a bit of difficult identifying motors as the propellant seems to be missing, would be nice to be able to do searches based on this.

SpaceManMat said:

I had a bit of difficult identifying motors as the propellant seems to be missing, would be nice to be able to do searches based on this.

Click to expand...

The case and propellant info should be listed on the Motor Details page. (If you select an item in the list, you can see all motor details.) If you find a motor for which the propellant type is missing that has that info in ThrustCurve.org, please let me know.

JohnCoker said:

The case and propellant info should be listed on the Motor Details page. (If you select an item in the list, you can see all motor details.) If you find a motor for which the propellant type is missing that has that info in ThrustCurve.org, please let me know.

Click to expand...

All the 38mm CTI motors I looked at in the App are missing propelent types but have them online

SpaceManMat said:

All the 38mm CTI motors I looked at in the App are missing propelent types but have them online

Click to expand...

I just did a motor search for all 38mm CTI reloads and they all display propellant type.

SpaceManMat said:

All the 38mm CTI motors I looked at in the App are missing propelent types but have them online

Click to expand...

Thanks, I'll look into it.

I just loaded the app this morning. Awesome! Thank you for your work on this and the contributions you continue to make for the rocketry community.

Feedback and a couple questions:
1) I am also not seeing the propellant type for any of the 29 or 38mm CTI motors I just searched. From previous posts on this thread it looks like some users have this issue and some do not. Wondering if this is platform specific. I am using iOS
2) When you search motors and the 'Search Criteria' window pops up saying '52 results matched your search; first 20 shown.' How do you get to the next 20 in the list?
3) Knowing very little about the process you went through developing the app for the iOS phone, how much more effort would be involved with making the iOS version available for the iPad?

kjkcolorado said:

2) When you search motors and the 'Search Criteria' window pops up saying '52 results matched your search; first 20 shown.' How do you get to the next 20 in the list?

Click to expand...

Right now, there isn't one; you have to narrow down the search criteria. I will change the max number of results in the next version.

kjkcolorado said:

3) Knowing very little about the process you went through developing the app for the iOS phone, how much more effort would be involved with making the iOS version available for the iPad?

Click to expand...

It would be an entirely different app to take advantage of the additional screen real estate. I think tablets are large enough to use the web site so I don't plan to build a tablet app.

Got it. I'll look forward to the next version. Good point about using the full site when using a tablet.

John, I don't know if you did anything on your end, but as of this morning the propellant types are now showing up in the motor search listings.

kjkcolorado said:

John, I don't know if you did anything on your end, but as of this morning the propellant types are now showing up in the motor search listings.

Click to expand...

Yeah, I just tried to reproduce the problem and was unable to. If anyone sees it again, please note the exact search and which motor was missing the propellant and case info.

VernK said:

Can you do a pop-up on that screen the first time a user ever accesses it?

Click to expand...

That's a good idea, and I've been experimenting with it. I'm not sure they're quite the right style, but here's what I have so far:

I have a question, John.

In both your app and the on the website, if you run the Motor Guide you can see various data the sim(s) produce. I've always wondered why the Time To Apogee is almost always greater than the Optimum Delay time. It would seem the Optimum Delay time should be equal to or slightly greater than the Time To Apogee.

In one particular case, when using the suggested delay of 8 seconds I popped well below apogee. I relaunched twice with the same rocket and motor combination (Crayon Rocket and CTI I195). The 9 second delay was still a bit below apogee. I finally got an apogee deployment with a 10 second delay. The sim(s) show a Time To Apogee of 10 seconds.

Am I missing something or am I misunderstanding the data presented by the Motor Guide. Both are possible explanations.

Think of it as optimum delay AFTER motor burn and it will make sense.

My experience with the site has been the opposite..punch in weight and diameter and the delay has been spot on..but the motor will fire the ejection a little early or late.

Kenny

KenRico said:

Think of it as optimum delay AFTER motor burn and it will make sense.

Click to expand...

Exactly. The convention in the hobby is to measure delay after burn-out because end-burning black powder motors worked this way. This is true even for core-burning motors where the delay actually starts burning at the same time as the motor.


From the LUNAR web site.

Version 1.1.1 has just been released:

• indicate places where rotating the phone shows different view
• increase motor search result limit
• motor search results sort by total impulse
• request all motor info when searching
• added Settings View page to configure extra detail columns
• changing guide length in Motor Guide saves to rocket

Thanks to those who reported bugs and made suggestions.