LABORATORY O-3 Orbit Mechanics and Attitude Dynamics

Description

PART I: Sun-Synchronous Orbits

Using STK 12/Astrogator, you will create a scenario with a satellite orbiting the Earth, designing the orbit to be sun-synchronous. Follow the outlined procedure and answer the questions presented throughout.

1. A sun-synchronous orbit leverages the effect of the Earth’s oblateness on the secular evolution of the RAAN to achieve an orbit whereby the orbital plane maintains a constant angle with the radial direction to the Sun. Such satellites may be useful for remote sensing applications. Recall that the effect of oblateness on the RAAN and argument of perigee are expressed as follows:

1. • • 3 √_!^!

   • ^{= − %}_{2 (1 −} !₎! “⁄!^{1 cos}

2. Create a scenario with the Earth as the central body. Select the initial epoch for the scenario as February 21, 2020 19:00:00.000 UTCG, and a final scenario time of February 28, 2020 19:00:00.000 UTCG.

3. Add a satellite to the scenario and select Astrogator as the propagator.

Question 1: Using the rates of change for the RAAN and argument of periapsis, design a sun-synchronous orbit that also satisfies all of the following criteria, by selecting the orbital elements for the initial state at an epoch on February 21, 2020:

• Req. #1: An orbital period of 1.62 hours;

• Req. #2: A perigee altitude between 500 km and 600 km;

• Req. #3: A perigee that regresses over time; and

• Req. #4: After one orbital period, the ascending node should possess a longitude of zero to within a tolerance of 0.1 degrees (i.e. its location on the ground track should lie on the Greenwich meridian).

• Req. #5: An initial argument of perigee equal to 0 degrees.

Note that there may not be a unique solution to this problem, and some parameters may not even be constrained. You should justify your choice of any relevant orbital elements in your lab report, showing your working.

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Orbits Lab 3

ASEN 3200 Lab O-3 Rubric

Title Page (1 pt.) – Lab, Course Number, Group Members, Date

Abstract (5pts) – short summary of objectives, experiment, results, and analysis Introduction (5pts) – brief introduction to this lab, what you plan to investigate, etc

Within the writeup in the below sections, using subheadings such as “Question X” to clearly identify your answer to each question.

PART I: Sun Synchronous Orbits (35 pts)

• Description of scenario setup and initial parameters

• Theory – explain, with equations, how you calculate the orbital elements for your orbit.

• Results and Analysis – show all plots and summarize output generated from STK, describe results. Ensure that any plots are clear and 3D graphics views provide a useful perspective of the orbit. Justify your responses to any questions.

PART II: Bound for Mars (35 pts)

• Description of scenario setup and initial parameters

• Theory – explain, with equations, how you calculated the TOF and maneuvers required for each of the Hohmann and bielliptic transfers.

• Results and Analysis – for each question, show all plots and summarize output generated from STK and describe results. Ensure that any plots are clear and 3D graphics views provide a useful perspective of the orbit. Justify your responses to any questions.

Conclusions and Recommendations (4 pts)

• What did you learn from this lab?

• What would you be interested in exploring beyond the given objectives or STK features?

Acknowledgements (1 pt.)

List who did what in the group and any outside assistance you received

References (1pt, must cite all external sources, including images)

Style & Clarity (13 pts)

Organization (3) – clear flow, follows required outline, numbered pages

Figures (2.5) – clear figures, appropriate axes, informative titles, clearly labeled units

Tables (2.5) – clear tables, significant figures, headings, informative titles, clearly labeled units Spelling & Grammar (5)