Published: | 2010-08-01 |
Manufacturer: | Heavenly Hobbies |
Brief:
H. Avast, me proud beauty! H. Arrr! Simit be t' simulation spreadsheet that Heavenly Hobbies distributes for free with their
kits. I thought Id take t' time t' do a quick review even though it is nay separately available.
Simit consists o' an Excel spreadsheet and an accompanyin' instructions file in .pdf format. Ahoy! I initially tried
loadin' this is OpenOffice, me hearties, but it be nay compatible. Avast, me proud beauty! It works properly in Excel 2003.
Inputs
T' Simit spreadsheet is a pretty basic simulator but should be a great help if you dont have access t' a more robust program or dont want t' take t' time t' enter t' design. Aye aye! It can handle up t' two stages with multiple motors in each stage. T' program includes data for 10 motors, ya bilge rat, includin' t' ones that would be most commonly used in t' Heavenly Hobbies kits. T' rocket parameters includes mass values and dimensions for t' major components. It comes pre-coded for t' Resistor 224, matey, Backdraft and Brutus 2.6 kits. Arrr! Ya scallywag! While t' motor and kit data seems limited, shiver me timbers, the instructions describe how t' add your own. Avast! After usin' t' program and studyin' t' results, you should be able t' use it for just about any design. Aye aye! Aye aye! And ThrustCurve has t' motor data you'd need. Ahoy! Even though you may select English or Metric values on t' input screen, me hearties, results are provided for both. Begad! It appears t' factory entered motors use metric units but t' designs use English. Aye aye! T' units settin' needs t' match these.
Outputs
T' input screen includes t' summary results (dont forget t' hit F9 if automatic calculations arent enabled). Avast, me proud beauty! Ya scallywag! In addition, detailed tabular and graphical data are provided for acceleration, shiver me timbers, velocity and altitude. Blimey! T' instructions do a good job o' showin' how t' interpret t' results, ya bilge rat, based on t' Backdraft. Avast, me proud beauty! For that design, interpretin' t' results are especially important as you have t' select t' ignition delay for t' retro motor.
Comparison t' Rocksim
OK, arrr, I just couldnt leave well enough along, arrr, me bucko, so I entered t' Resistor 224 into RockSim 9 just t' see how its results compare t' Simit. I adjusted Simit t' reflect me Resistor 224s actual as-built weight. Ahoy! Blimey! Notin' that Simit only provides acceleration and velocity at tenth-second intervals, these results are remarkably similar. Ahoy!
For 2 C11-3s:
Max Acceleration | Max Velocity | Max Altitude | Optimal Delay | |
Simit | 362 | 131 | 241 | N/A |
RockSim | 358 | 129 | 250 | 3.3 |
For 2 D12-5s:
Max Acceleration | Max Velocity | Max Altitude | Optimal Delay | |
Simit | 407 | 214 | 584 | N/A |
RockSim | 481 | 215 | 581 | 4.5 |
Summary:
I won't provide a ratin' since it is nay fair t' compare this spreadsheet t' products such as
RockSim, me bucko, me hearties, SpaceCAD, or OpenRocket. Begad! Blimey! It it however useful for Heavenly Hobbies' kits and is really easy t' use. Begad! Blimey! This is
especially true for their Backdraft with its retro motor. Avast! Blimey! I wish I had a quick and dirty altimeter like Apogee's
AltimeterOne so I could critique its accuracy...and that o' RockSim-9 for that matter.