Advanced Spacecraft Dynamics and Control

Overview

Syllabus

Courses

• 0 reviews

  1 day 8 hours 4 minutes

  View details

  This course is part 2 of the specialization Advanced Spacecraft Dynamics and Control. It assumes you have a strong foundation in spacecraft dynamics and control, including particle dynamics, rotating frame, rigid body kinematics and kinetics. The focus of the course is to understand key analytical mechanics methodologies to develop equations of motion in an algebraically efficient manner. The course starts by first developing D’Alembert’s principle and how the associated virtual work and virtual displacement concepts allows us to ignore non-working force terms. Unconstrained systems and holonomic constrains are investigated. Next Kane's equations and the virtual power form of D'Alembert's equations are briefly reviewed for particles. Next Lagrange’s equations are developed which still assume a finite set of generalized coordinates, but can be applied to multiple rigid bodies as well. Lagrange multipliers are employed to apply Pfaffian constraints. Finally, Hamilton’s extended principle is developed to allow us to consider a dynamical system with flexible components. Here there are an infinite number of degrees of freedom. The course focuses on how to develop spacecraft related partial differential equations, but does not study numerically solving them. The course ends comparing the presented assumed mode methods to classical final element solutions.
• 0 reviews

  1 day 21 hours 8 minutes

  View details

  This course is part 1 of the specialization Advanced Spacecraft Dynamics and Control. It is a direct continuation of the Coursera specialization Spacecraft Dynamics and Control. This first course focuses on nonlinear attitude feedback control using a range of angular momentum devices. The course provides a comprehensive review of prerequisite material. Next it develops equations of motion of a spacecraft with momentum exchange devices such as reaction wheels (RWs), control momentum gyroscopes (CMGs) and variable speed control moment gyroscopes (VSCMGs). The course discusses developing a complex spacecraft simulation with a number VSCMGs and how to approach debugging such complex software. The use of the work/energy theorem is discussed to assist with debugging the simulation by validating angular momentum, energy, changes in momentum and mechanical power. Further, the use of null motion is explored to reconfigure the attitude control devices to avoid singularities and gimbal lock. The redundancy is exploited to seek control solutions that avoid classical CMG singularities.
• 0 reviews

  16 hours 24 minutes

  View details

  This capstone course is the 3rd and final course of the specialization Advanced Spacecraft Dynamics and Control. It assumes you have completed the prior courses on "Attitude Control with Momentum Exchange Devices" and "Analytical Mechanics for Spacecraft Dynamics". This project course investigates the dynamics of a complex spacecraft system where there is a rigid hub onto which a hinged panel is attached. This simulates a spacecraft with a time varying geometry. First, the three-dimensional kinematics of this system are explored. Analytical relationships of the body and panel position and velocity states are derived, and the center of mass properties of this system are explored. Next, a simplified system is used to use Lagrange's equations of motion to predict the dynamical response. With these differential equations we are then able to apply attitude control torques and investigate the rotational response if the spacecraft hub has a spring-hinged panel attached. Two open-loop control torque solutions are investigated. The classical minimum time bang-bang control solution is applied first, illustrating how such a control can yield unwanted panel oscillations. Finally, a filtered version of the bang-bang control is applied to illustrated how the panel oscillations can be significantly reduced at the cost of a slightly longer nominal maneuver time.

Taught by

Hanspeter Schaub

Tags

• united states