SD2910 Spacecraft Dynamics 9.0 credits

Rymdfarkosters dynamik

  • Education cycle

    Second cycle
  • Main field of study

    Mechanical Engineering
  • Grading scale

    A, B, C, D, E, FX, F

Course offerings

Spring 19 for programme students

Spring 20 for programme students

Intended learning outcomes

This course gives a deep understanding of modern spacecraft attitude dynamics and control. Rotational kinematics and dynamics of the spacecraft in orbit and different methods to passively or actively control the attitude are studied as well as implementation of nonlinear control laws for reaction wheels and variable speed control moment gyroscopes.

After the course you should be able to:

  • Explain and use various parameterizations of rigid body kinematics in three dimensions: direction cosine matrix, Euler angles, principal rotation vector, Euler parameters (quaternions), classical Rodrigues parameters and modified Rodrigues parameters.
  • Formulate and solve rotational torque-free dynamics problems in three dimensions.
  • Formulate the attitude stability conditions for non-spinning and spinning spacecraft.
  • Formulate constrained nonlinear modern attitude control laws based on Lyapunov stability functions, select suitable gain values, solve the problems numerically and evaluate the results.
  • Implement nonlinear attitude control laws in reaction wheels and variable speed control moment gyroscopes, solve the problems numerically and evaluate the results.

Course main content

Part 1: Rigid body kinematics parameterizations in three dimensions: Direction cosine matrix, Euler angles, principal rotation vector, Euler parameters (quaternions), classical Rodrigues parameters and modified Rodrigues rarameters.

Part 2: Rigid body dynamics: angular momentum, kinetic energy and moment of inertia in three dimensions, Euler’s rotational equations of motion, torque-free rigid body rotation, dual-spin spacecraft, momentum exchange devices and gravity gradient stabilization.

Part 3: Nonlinear spacecraft stability and control: stability definitions, Lyapunov stability, Lyapunov functions, nonlinear feedback control laws, Lyapunov optimal control laws and linear closed-loop dynamics.

Part 4: Nonlinear control law implementation in control devices: reaction wheels and variable speed control moment gyroscopes.

Disposition

The course is given together with the course SG2805 Spacecraft Dynamics on advanced level. The lectures briefly introduce the topics and methods used to solve the problems on the problem sheets. The workshops are tutored and the students are strongly encouraged to work in groups. The problem sheets cannot be finished during scheduled hours, so work on problem sheets during non-scheduled hours is required to meet the deadlines.

Eligibility

Good knowledge in mathematics, mechanics and numerical methods from MSc education in Aerospace Engineering, Mechanical Engineering, Engineering Mechanics or Engineering Physics.

Literature

Schaub, H. & Junkins, J. L. Analytical Mechanics of Space Systems, 2nd edition, AIAA Education Series, 2009.

Supplementary material in the form of research articles will be provided.

Required equipment

The software Matlab is used throughout the course. Students are expected to use their own computers to solve the problems on the homeworks.

Examination

  • PRO1 - Assignments with Oral Presentation, 4.0, grading scale: A, B, C, D, E, FX, F
  • TEN1 - Oral Examination, 5.0, grading scale: A, B, C, D, E, FX, F

Requirements for final grade

The participants are required to complete the following:

  • Four problem sheets, related to the four parts of the course. The problem sheets are released at given dates and have to be submitted for correction before given deadlines.
  • Oral presentation of selected problem sheet problems in front of class. The presenting students are randomly selected.
  • Oral examination on all four parts of the course.  

Offered by

SCI/Aeronautical and Vehicle Engineering

Examiner

Gunnar Tibert <tibert@kth.se>

Version

Course syllabus valid from: Autumn 2014.
Examination information valid from: Autumn 2014.