SWAGºÏ¼¯

To provide a critical understanding of the basic principles of Astrodynamics and Mission Analysis and of their application to typical mission analysis problems.

Astrodynamics - Keplerian orbital motion

• Newton’s Law of Gravitation.
• Equations of Motion for a two body system.
• Motion in a Central Field. Conic Sections.
• The Geometry of the Ellipse. Kepler's Laws.
• The Position-Time Problem.
• The Energy Integral.
• The Satellite Orbit in Space.

Astrodynamics - Orbit Perturbations. 

• Variation of Parameters.
• Perturbations Caused by Earth Oblateness.
• Perturbations Caused by a Third Body.
• Triaxiality Perturbations.

Mission analysis

• Orbit Selection for Mission Design.
• Hohmann Transfer and Inclinations Changes.
• Hyperbolic Passage.
• Patched Conics Interplanetary trajectories.

On completion of this module you should :

• Be able to apply appropriate techniques to solve a range of practical astrodynamics and mission analysis problems.
• Be able to describe widely used orbit types and their applications, and evaluate the perturbations on these orbits.
• Be able to plan impulsive orbital manoeuvres to achieve mission design requirements.

To demonstrate how to develop the design of a space system, from the initial mission objective, through requirements definition, concept development and trade-off, and through to a baseline design.

• Brief history & context: Background to the development of space, agencies, funding, future missions.
• Introduction to space system design methodology: requirements, trade-off analysis, design specifications, system budgets.
• Spacecraft sub-systems design: Structure & configuration; Power, the power budget and solar array and battery sizing; Communications and the link budget; Attitude determination and control; Orbit determination and control; Thermal control.
• Mission and payload types Spacecraft configuration: examples of configuration of spacecraft designed for various mission types; case study.
• Introduction to cost engineering.
• Space and Spacecraft Environment: Radiation, vacuum, debris, spacecraft charging, material behaviour and outgassing.
• Assembly, Integration and Test processes; Launch campaign; Space mission operations.

To provide an understanding of the physics fundamentals and thermofluid dynamic concepts underlying space propulsion and their implications for launch vehicle and spacecraft system performance and design.

Introduction: The interactions between propulsion system, mission & spacecraft design.

Spacecraft Performance: Mission requirements, Vehicle dynamics, Tsiolkovski rocket equation, Launch vehicle sizing and multi-staging. Illustrative launcher performance (Ariane, Shuttle programmes, Falcon...). Launch site/range safety constraints, Geostationary orbit acquisition.

Launch Vehicles: Current Options: Vehicle design summaries, Orbital transfer vehicles, Comparative launch costs, and Reusable launchers.

Propulsion Fundamentals: Systems classification, Nozzle flows, Off-design considerations (under/over-expanded flows), Thermochemistry.

Space Propulsion Systems and Performance: Propellants and combustion, Solid and liquid propellant systems, Engine cycles: Spacecraft propulsion—orbit raising, station-keeping and attitude control, Propellant management at low-g—alternative storage and delivery systems: Electric propulsion, Separately Powered rocket performance, Low thrust manoeuvres, Thruster concepts and configurations.

Alternative propulsion concepts and future developments: Overview of potential alternatives to current (or common) propulsion systems and their advantages, problems, or feasibility. This includes Sails, Nuclear propulsion, Air-Breathing, Space Elevators.

On successful completion of this module you should be able to:

1. 1. Demonstrate a critical understanding the constraints imposed by launch vehicle performance & operation on mission analysis.
2. 2. Understand the impact of molecular mass of the propellant on thruster performance.
3. 3. Use fundamental physics relationships to perform initial propulsion system design point, off-design calculations, and mission analysis.
4. 4. Be familiar with the principal options for propulsion system design in relation to both boosters and secondary spacecraft propulsion and be able to critically assess their relative strengths in a range of mission applications.
5. 5. Understand the fundamental methods to model thruster performance, its key results, and the limitations of the techniques.

To provide you with both an introduction to the theory underpinning finite element analysis (FEA) and hands on experience using the well-established FEA package.

• - Background to Finite Element Methods (FEM) and its application.
• - Introduction to FE modelling: Idealisation, Discretisation, Meshing and Post Processing.
• - Tracking and controlling errors in a finite element analysis. ‘Do’s and don’ts’ of modelling.
• - Illustration of basics of FEM using the Direct Stiffness method to define both terminology and theoretical approach.
• - Problems of large systems of equations for FE, and solution methods.
• - FE method for continua illustrated with membrane and shell elements.
• - Nonlinear analysis in FEM and examples.

On successful completion of this module you should be able to:

1. 1. Understand the underlying principles and key aspects of practical application of FEA to structural problems.
2. 2. Understand the main mathematical and numerical aspects of the element formulations for 1D, 2D and 3D elements.
3. 3. Build and analyse finite element models based on structural and continuum elements with proper understanding of limitations of the FEM.
4. 4. Interpret results of the analyses and assess error levels.
5. 5. Critically evaluate the constraints and implications imposed by the finite element method.

To provide an introduction to spacecraft kinematics and dynamics, focussing on rigid body dynamics and control of Earth orbiting satellites.

Overview:
• How does spacecraft dynamics relate to satellite control problem?
• AOCS (Attitude & Orbit Control Sub-system) design process.
• Interactions with other sub-systems.
• Control loop representation.

Kinematics:
• Attitude representation: Euler angles, Euler parameters (quaternions).
• Common reference frames (inertial, orbit referenced).
• Transformation between reference frames.
• Small angle linearisation (reduction of 3dof control problem to 1dof).

Rigid body dynamics:
• Euler's equations for rigid bodies.
• Axisymetric spacecraft & free-body dynamics.
• Disturbance torques.

Application to spacecraft control:
• Simulating spacecraft free-body kinematics & dynamics in MATLAB.
• Sensor basics (sun sensors, star trackers, rate sensors).
• Actuator basics (thrusters, reaction wheels).
• Rate control of rigid body spacecraft.
• Attitude control of 3-axis stabilised spacecraft.

• Dr Leonard Felicetti

The aim of this module is to provide you with an introduction to the principles of aerospace navigation systems based on inertial sensors and satellite navigation and how such data can be blended to provide improved navigation solutions (typically using a Kalman filter).

Overview of navigation principles, typical applications; axis systems and projections,

Inertial Navigation Systems:

• Principles of inertial navigation; Sensors: accelerometers, gyroscopes, specific technologies such as Fibre Optic Gyros; Axis transformations and mechanisation of IN equations; Errors in inertial navigation, Schuler loop tuning, INS modelling & aiding

  GNSS:

• Development history of GNSS and current systems worldwide (GPS, Galileo, etc.), system architecture (ground, space, user segments); measurement principles; error sources (natural, other); Augmentation: differential GPS (local, wide area), other sensors (e.g. INS); Applications / issues: user groups (aviation, space), integrity (RAIM), accuracy, reliability

Random Signals and Random Processes,

Measurement in noise (including aspects of instrumentation),

Error Analysis,

Discrete Kalman Filter, including the Extended KF,

General approaches to data fusion.

On successful completion of this module you should be able to:

• Evaluate designs of navigation systems based on an understanding of inertial and satellite navigation in aerospace,
• Assess performance limitations of navigation systems due to the typical error sources of individual sensors and of the complete system,
• Explain the principles of data acquisition systems and design a basic system,
• Design and implement a simple Kalman filter to process measurements and estimate position, velocity, etc,
• Appreciate the design methods using to integrate aerospace navigation systems.

To provide you with an introduction to the state-of-the-art in applied mathematics and techniques in astrodynamics and trajectory design.

1. Refresher of Matlab Programming:

• • The Matlab Environment.
• • Matrices and Operators.
• • Scripts and Functions.
• • Loops.
• • Programmer’s toolbox.

2. Lambert Arc:

• • Two-body orbital boundary-value problem.
• • Minimum energy transfer.
• • F & G Solutions for elliptic orbits.
• • Differential Correctors and Continuation methods.

3. Pork-chop plots:

• • Hohmann transfer and Patched Conics.
• • Lambert arc grid search and visualisation.
• • Earth Escape and C3.
• • Synodic Period.

4. Low thrust trajectory design:

• • Gravity losses.
• • Method of variation of parameters and sub-optimal control laws.
• • Edelbaum Solution.
• • Shape-base methods.

5. Circular Restricted Three Body Problem:

• • Synodic reference frame.
• • Equations of motion.
• • Jacobi Integral.
• • Equilibrium Points.
• • Zero Velocity Curves.

6. Libration Point Orbits:

• • Stability of the equilibrium points.
• • Classification of Fixed Points.
• • Periodic Orbits near L1 and L2.
  
  

On successful completion of this module you should be able to:
1. Write reliable code to solve realistic mission analysis scenarios.
2. Apply a range of applied mathematical techniques to solve trajectory design problems and be able to independently expand on appropriate tools and know-how when necessary.
3. Reflect on current challenges for trajectory design, and their synergy with space system engineering, for both Earth observation and interplanetary missions.
4. Identify most common non-Keplerian orbit types and explain their applications.

To provide fundamental knowledge on control and estimation theories and their application in guidance navigation and control schemes in space systems.

Control and Estimation Theory: 

• State Space Representation of Dynamic Systems.

• Stability and Controllability of Linear and Non-Linear Systems.

• Design of Feedback Control Laws (PID, LQR).

• Observability and Estimation of Dynamic Systems.

• Kalman Filters (Linear, Extended).

• Definition and Solution of Optimisation Problems.

• Space-Based Applications.

• GNC applications for Spacecraft Rendezvous and/or Planetary Rovers.

• Optimal Manoeuvres in Space 

On successful completion of this module you should be able to:

1. Demonstrate a Critical Understanding of Control and Estimation Techniques and their Application in Space Systems.

2. Model and Analyse the Stability, Controllability and Observability of Dynamic Systems, with a particular focus to Space Applications.

3. Select, Design and Implement Appropriate Control and Estimation Techniques in Matlab to Solve a Range of Space-based GNC-Problems.

4. Describe, Analyse and Evaluate Numerical and Simulation Results in a Technical Report

This module aims at provide you with a thorough understanding of satellite commutations system design and overview current approaches of communications data link between spacecraft and ground station.

• Overview of Satellite Communications.
• Satellite Terminals, Space and Ground Segment.
• Satellite Communications for Air Mobility.
• Multiplexing and Transmission Techniques.
• Analogue and Digital Modulation Schemes.
• Communications System Design (Uplink/Downlink Model, Noise, SNR, Bit Error Rate).
• Link Budget Design.
• Antenna System and Ground Terminal Design.
• Channel Capacity Techniques.

On successful completion of this module you should be able to:

1. Distinguish the fundamental principles of satellite communications.

2. Assess different types of modulation and multiplexing techniques.

3. Analysis link budget & communications system design and air mobility.

4. Estimate different antenna types, characteristics and applications.

5. Evaluate channel capacity and coding techniques.

To develop an understanding of the composite materials used in engineering structures.

• Introduction to composite materials, types of material and manufacturing methods.
• FRP constituents: fibres and resins.
• Micromechanics of a lamina.
• Analysis of an individual ply.
• Macro-mechanics of a laminate; stiffness, strength and analysis techniques.
• Residual stresses due to temperature effects and moisture.
• Stress distribution around holes in laminates.
• Test methods; determination of elastic constants, static strengths, fibre volume fractions and void content.
• Structural Design and Manufacturing considerations.