Rocketry software for PalmOS updates

Oct 27, 2003 7 Replies

pRASP, RocketCalc and the motor database have had a few upgrades. They're all available for download from .



Both pRASP and RocketCalc can now beam individual motors from the motor database to another PDA, or beam the entire database.



pRASP now allows you to set both the launch site elevation and launch rod length.



RocketCalc has a new calculator to help you calculate static port sizes.



The motor database has had a thorough cleaning; all motors data available from NAR and thrustcurve.org (as well as the newer CTI motors) are now included, and the motors are now presented in order of increasing average thrust with motor classes (meaning that the M520 will now come before the M1000).



For people who aren't already using pRASP or RocketCalc on the PDA, I've included a description of what they do below.



Wayne



-------------------- pRASP is a port of RASP (Rocket Altitude Simulation Program) for PDAs running Palm OS. RASP was originally written by G. Harry Stine and was published as an appendix in his classic book Handbook of Model Rocketry.



pRASP adds to RASP the ability to enter values and display output data in a variety of units. pRASP is limited to a maximum of 2 stages due to the small screen real estate available on Palm PDAs.



pRASP allows you to customize the launch site altitude, and launch rod length. It also allows you to beam the entire motor database, or individual motors, to another Palm PDA.



-------------------- RocketCalc is a collection of seven rocketry related calculators for PDAs running Palm OS. Data (and results) that are common across the calculators is retained when you switch, meaning you never have to enter the same figure twice!


  • The Parachute Calculator can calculate parachute size, descent speed or rocket weight given the other two variables.


  • The Delay Calculator will tell you how much time will pass between motor burnout and apogee for a given rocket and engine combination, allowing you to figure out in an instant which delay you need. (pRASP will give you the same information, and also allows you to simulate up to two stages; the RocketCalc Delay calculator is a simplified version that only allows one stage, and uses simplified calculations to give you an instant answer.)

  • The Altitude Calculator uses data from either one or two tracking states to calculate the altitude reached by a rocket. Three different methods of calculation are available: geodesic, vertical midpoint, and single station (elevation only).


  • The Ejection Calculator can tell you how much black you need to pressure a cylinder, how much pressure a given charge will result in, and just how much force it will exert on the bottom of the nose cone.

  • The Wind Drift Calculator calculates how far downwind you can expect a rocket to drift as it comes down on it's parachute.


  • The Motor Info Calculator calculates the maximum weight a given motor can lift at any thrust to weight ratio between 2:1 and 7:1. It also allows you to beam the entire motor database, or an individual motor, to another PDA.

  • The Static Port Calculator calculates the required size of static ports for altimeter pressure sensors (using the 'one ¼" hole for every 100 cubic inches of bay space' rule).

All seven calculators allow you to use just about any combination of units you like: inches, feet, meters, centimeters, miles, kilometers, pounds, ounces, grams or kilograms.



-------------------- The Motor Database is used by both pRASP and RocketCalc. All motors found at thrustcurve.org are included, as well as all of the newer CTI motors certified by CAR (including the brand new M520). Both pRASP and RocketCalc can beam both the database, and individual motors, to another PDA; which can be very handy when you consider that the Motor Database is completely customizable. You can use or create your own RASP.ENG file on your PC and use the included utility program ENG2PDB to create a new motor database to be downloaded to your PDA.


Great! Just in time for my new color PDA! I've beamed the older pRASP & Rocketcalc over to my Zire 71 and it runs fine. And it's a LOT faster than on my older unit due to the better processor.

For those who haven't played with this yet, I strongly recommend it. I've been using it since this spring when Wayne first announced it. Sicne it's always in my pocket, it's the ultimate in convenience.

Now if only VCP were ported to the PDA...

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Might be a bit much to bite off all at once; how about Barrowman? Even that's going to be a fair amount of data to input (and as you've probably already found out by playing with the NP Palm port, inputting large amounts of data is one thing Palms aren't exactly great at), but it's certainly doable in the short term.

Wayne

Wayne wrote: pRASP, RocketCalc and the motor database have had a few upgrades. They're all available for download from .

A. Rocketeer says: I can't say enough about how useful there utilities are. I've got an old Palm V that has now become a permanent addition to my range supplies based on the wonderful utility of the both pRASP and RocketCalc. The delay finder of RocketCalc has worked very well helping set the delay using Pro38 motors and the ProDAT tool. Being able to calculate drift, descent rate, etc. at the field is really great on windy days.

Although pRAST does run a little slow on my Palm V, it is very accurate. It's nice to be able to run a sim at the field using a motor that I'm thinking of purchasing and knowing if it's a good choice.

Thanks for all your hard work,

A. Rocketeer.

Yes, thanks for all the hard work! These programs work great!

Mike

But if you have long since input the baseline data and the input utility is properly designed, minor mods can be done (tube lengths, fin thickness, whatever), and rerun on the field.

After I complained about the speed in the first version, Wayne added an option to adjust the integration time. If you use a more recent version, select the Info button on top, options, preferences, and reduce the interval from 0.001 to 0.01 second, it runs much faster.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required