1. Why Design Tool? 93 年 10 月 21 日

2. EPS Course - 2 Simple Problems ----------------------- Close form solution Complex Problems --------------------- Computer Software Overly Complex Problems ------------ ????? Accuracy is Critical to Spacecraft Design Why Design Software ?

3. EPS Course - 3 Software Skill Understand Input Data Generate Results Modeling Techniques Generate Accurate Results Output User’s Manual Input Background Theories Test Data Correlation

4. EPS Course - 4 Commonly Used Software for Spacecraft Design SPACECRAFTSPACECRAFT Mission Analysis ADCS Electrical Power Thermal Control Structure Analysis Flight Software STK: Orbit dynamics simulation including orbit trajectory, ground trace, and visibility access, etc. NASTRAN: Finite element code for static and dynamic analysis. PATRAN: Preprocessor for finite element code. TRASYS: Calculate internal and external radiation conductor. SINDA: Construct thermal network model which include the TRANSYS output radiation conductor to calculate temperature distribution. MATLAB: Synthesize control law, perform dynamic modeling for spacecraft, actuators, sensors, and perform linear stability analysis for the control system. STK: Every possible and worst case orbit beta angle. OrCAD V9.0 : Electrical Power Circuit modeling and analysis PK51-8051: Integrated Development Environment, including Editor, Assembler, Compiler, linker, Debugger, HEX converter, target monitor, and real-time kernel.

5. Orbit Power Analysis & STK Tool 朱崇惠 92 年 10 月 21 日

6. EPS Course - 6 Power Analysis Principle Power Generation –Photovoltaic type: Solar Array  Operation duty cycle  Sun/eclipse time -> Orbit  Beta angle -> Orbit  Sun angle -> Orbit, Attitude, Articulation  Obscurity -> Form, Attitude, Orbit Power Consumption –Satellite Load  Operation duty cycle  Sun/eclipse time -> Orbit –Energy storage replenish  Peak power demand  Sun/eclipse time -> Orbit

7. EPS Course - 7 STK’s function for power analysis Time Input Orbit epoch Build-in tool Map Orbit Propagator AttitudeSun/Moon ephemeris Geometry calculationSatellite Facility Sensor Output Orbit Parameters Geometry Parameters Time Visualization Position

8. EPS Course - 8 ROCSAT2 Orbit Example

9. EPS Course - 9 Generate a sun-synchronous orbit

10. EPS Course - 10 Sun/Eclipse Time Interval Satellite-ROCSAT2: Eclipse Times Start Time (UTCG) Stop Time (UTCG) Duration (sec) Current Condition Total Duration (sec) ----------------------- ----------------------- -------------- ----------------- -------------------- 22 Jun 2004 12:50:51.65 22 Jun 2004 12:51:02.83 11.182 Penumbra 1922.816 22 Jun 2004 12:51:02.83 22 Jun 2004 13:22:43.44 1900.603 Umbra 1922.816 22 Jun 2004 13:22:43.44 22 Jun 2004 13:22:54.47 11.031 Penumbra 1922.816 22 Jun 2004 14:33:46.49 22 Jun 2004 14:33:57.67 11.182 Penumbra 1922.768 22 Jun 2004 14:33:57.67 22 Jun 2004 15:05:38.23 1900.554 Umbra 1922.768 22 Jun 2004 15:05:38.23 22 Jun 2004 15:05:49.26 11.032 Penumbra 1922.768 22 Jun 2004 16:16:41.33 22 Jun 2004 16:16:52.51 11.183 Penumbra 1922.720 22 Jun 2004 16:16:52.51 22 Jun 2004 16:48:33.02 1900.505 Umbra 1922.720 22 Jun 2004 16:48:33.02 22 Jun 2004 16:48:44.05 11.032 Penumbra 1922.720 22 Jun 2004 17:59:36.17 22 Jun 2004 17:59:47.35 11.184 Penumbra 1922.672 22 Jun 2004 17:59:47.35 22 Jun 2004 18:31:27.81 1900.456 Umbra 1922.672 22 Jun 2004 18:31:27.81 22 Jun 2004 18:31:38.84 11.033 Penumbra 1922.672 22 Jun 2004 19:42:31.01 22 Jun 2004 19:42:42.19 11.184 Penumbra 1922.624 22 Jun 2004 19:42:42.19 22 Jun 2004 20:14:22.60 1900.406 Umbra 1922.624 22 Jun 2004 20:14:22.60 22 Jun 2004 20:14:33.63 11.033 Penumbra 1922.624 22 Jun 2004 21:25:25.85 22 Jun 2004 21:25:37.03 11.185 Penumbra 1922.575 22 Jun 2004 21:25:37.03 22 Jun 2004 21:57:17.39 1900.357 Umbra 1922.575 22 Jun 2004 21:57:17.39 22 Jun 2004 21:57:28.42 11.034 Penumbra 1922.575 22 Jun 2004 23:08:20.69 22 Jun 2004 23:08:31.87 11.185 Penumbra 1922.526 22 Jun 2004 23:08:31.87 22 Jun 2004 23:40:12.18 1900.307 Umbra 1922.526 22 Jun 2004 23:40:12.18 22 Jun 2004 23:40:23.22 11.034 Penumbra 1922.526 23 Jun 2004 00:51:15.53 23 Jun 2004 00:51:26.72 11.186 Penumbra 1922.477 23 Jun 2004 00:51:26.72 23 Jun 2004 01:23:06.97 1900.256 Umbra 1922.477 23 Jun 2004 01:23:06.97 23 Jun 2004 01:23:18.01 11.035 Penumbra 1922.477 23 Jun 2004 02:34:10.37 23 Jun 2004 02:34:21.56 11.186 Penumbra 1922.428 23 Jun 2004 02:34:21.56 23 Jun 2004 03:06:01.77 1900.206 Umbra 1922.428

11. EPS Course - 11 Orbit Beta Angle

12. EPS Course - 12 Solar Array Articulation –   orbit plane v.s. the sun –   the position of a spacecraft in one orbit Solar Array v.s. Spacecraft –Pointing of spacecraft body –Fixed mounted solar array –Solar array with one-axis rotation –Solar array with two-axes rotation

13. EPS Course - 13 RS2 Sun Vector

14. EPS Course - 14 Sun Angle Case 1: Lowest  angle Case 2: Summer solstice Case 3: Winter solstice Case 4: Highest  angle

15. EPS Course - 15 ROCSAT3 Orbit Example

16. EPS Course - 16 Orbit Beta Angle

17. EPS Course - 17 ROCSAT-3 Solar Array’s Pointing

18. EPS Course - 18 ROCSAT1 Orbit Example

19. EPS Course - 19 Orbit Beta Angle

20. EPS Course - 20 Summary (1) STK is a tool useful for orbit related analysis –Preliminary estimate –Preliminary design –Quick access –Visualized tool to acquire impression Correct setup for orbit configuration is important –Orbit parameter –Spacecraft attitude –Solar panel orientation With sun ephemeris, STK can provide a predict the availability of energy resources.

21. EPS Course - 21 Summary (2) Spacecraft attitude and solar panel articulation need to be modeled –Development of attitude simulation tool –Development of solar panel movement simulation tool –Model of solar panel STK data can be used as input/out for a separate modeling –Input/output data type –Input/output data format