Iterative, Concurrent Design of Advanced Space Transportation Systems EUCASS 2015 Vanessa Clark

Contents Introduction Collaborative and Concurrent Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Contents Introduction Collaborative and Concurrent Design Space Transportation System Process Chain Enabling Infrastructure and Methods for CLaVA Distributive Design Model-Based Systems Engineering Object Oriented Methods Conclusion Source: NASA

Introduction Scope of this presentation: > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Introduction Scope of this presentation: New initiative from DLR: Collaborative Launch vehicle Analysis (CLaVA) The development of a design process for STS (space transportation systems) Early-phase design Goal: enhance the interconnectivity and build competences between various DLR institutes in the area of space transportation. The aim is to make cooperation faster, more efficient and error-free. (investigation necessitated during requirements definition)

Versatility, flexibility, robustness Introduction > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Budget, time constraints Market and commercial aspects Versatility, flexibility, robustness Performance Political boundary conditions Introduction Motivation for this work: Rockets are hard (more on that later). External constraints are more predominant than technical complexities in STS design!

Collaboration is key! Introduction > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Introduction Collaboration is key! Map of Collaboration between Researchers Source: science-metrix.com

Introduction Materials (WF) System, configuration, trajectory (RY) > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Introduction Map of Collaboration between Researchers Source: science-metrix.com Source: LEGO System, configuration, trajectory (RY) Flight dynamics and control (SR) Solid rocket motors (AS) Materials (WF) Structure(FA) (BT) Liquid engines (RA) Aerodynamics, aerothermodynamics, flight dynamics and control (AS) Ground stations (RA) Combustion (VT)

Collaborative and Concurrent Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Collaborative and Concurrent Design Let’s have this….. ….. and avoid this!

Collaborative and Concurrent Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Collaborative and Concurrent Design DLR has a strong heritage in collaborative design… ? Aircraft Satellites Space Transportation

Collaborative and Concurrent Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Collaborative and Concurrent Design Objective: provide a new, flexible design environment to foster collaboration between experts in STS design

Collaborative and Concurrent Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Collaborative and Concurrent Design CEF Preliminary design X-TRAS Testing ? Development CLaVA MDO Distributive Design Environment Model-Based Systems Engineering

STS Design Process What is a Space Transportation System (STS)? > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process What is a Space Transportation System (STS)? It Shall be of Civilian Application It Shall Concern The Vehicle No megascale engineering projects that require large supporting infrastructures such as Space Elevators, Launch Loops, Space Cannons It shall fly and fly fast! Minimum velocity of the vehicle shall exceed Mach 5 at sea-level. It shall transport some payload or a crew. Source: ESA Source: Virgin Galactic

STS Design Process Energy Level 5 6 7 8 9 10 > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process Energy Level Heavier than Air With Wing Bodies Multi-Stage | Single Stage Heavier than Air With Lifting Bodies Reusable | Non-Reusable Heavier than Air Without Lifting Bodies Reusable | Non-Reusable Lighter than Air Reusable | Non-Reusable 5   6 7 8 9 10  Energy level Mach 5 5.0 - 10 6 10 - 15 7 15 - 20 8 20 - 25 9 25 -

STS Design Process Sequential Multidisciplinary Iterative > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process Sequential Inherent sensitivities between the design domains Parellelisation of tasks performed where possible to optimise time Multidisciplinary Preliminary models / analysis techniques generally much higher fidelity than for satellite design. E.g. structural analysis (beam method, FEM) Iterative Design must be iterated until convergence Domains: not subsystem!

STS Design Process Loop 3: Subsystems Loop 2: Higher fidelity analyses > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Loop 3: Subsystems Loop 2: Higher fidelity analyses Loop 1: Preliminary Sizing and Layout Loop 0: Requirements, design space definition STS Design Process Domain 1 Domain 2 Domain 3 Domain 4 Domain 5 Systems engineer MDO Domains: not subsystem!

STS Design Process Domains Systems: staging, configuration, mass > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Map of Collaboration between Researchers Source: science-metrix.com Source: LEGO System, configuration, trajectory (RY) Flight dynamics and control (SR) Solid rocket motors (AS) Materials (WF) Structure(FA) (BT) Liquid engines (RA) Aerodynamics, aerothermodynamics, flight dynamics and control (AS) STS Design Process Domains Systems: staging, configuration, mass Aerodynamics Propulsion (solid) Propulsion (liquid) Control (descent) Structure Thermal Trajectory Subsystems Control (ascent) Ground Domains: not subsystem!

SED: Systems engineer decision > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process SED: Systems engineer decision

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process

STS Design Process Loop 0 > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process Loop 0 Defines the mission statement and the project definition. Market analyses and customer validation are performed. The project definition, mission statement and high-level requirements are then translated into an implementation strategy. Initial concepts and technology choices are identified through consultation with the customer.

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Loop 1 Propulsion: Preliminary propulsion systems are calculated using fast engineering methods with an emphasis on system level performance and mass estimation.

Propulsion Block Description: > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Propulsion Block Description: The ascent and payload performance are calculated by combining more accurate results for system mass, aerodynamics and engine performance compared to loop 1. Input: System mass, aerodynamic database, engine performance and mission requiremenets. Process: Fast analytical ascent trajectory calculation and optimization resulting in vehicle payload performance. Output: Optimized trajectory evolution and payload mass.

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Loop 1 Mass: A preliminary mass model is constructed on system level using handbook-methods. Tool: STSM

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Loop 1 Aerodynamics: Stability analysis related specifically to longitudinal pitch is analysed. Trimmed aerodynamic database is composed. Trimmability during hypersonic flight is analysed. Trimmed aerodynamic database produced.

Blue, dashed vectors: Resuable launch vehicles only > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Blue, dashed vectors: Resuable launch vehicles only Loop 1 Trajectory: The ascent and payload performance are calculated by combining more system mass, aerodynamic database, engine performance and mission requirements. Fast analytical ascent trajectory calculation and optimization resulting in vehicle performance and payload mass.

Trajectory Block Description: > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Trajectory Block Description: The ascent and payload performance are calculated by combining more accurate results for system mass, aerodynamics and engine performance compared to loop 1. Input: System mass, aerodynamic database, engine performance and mission requiremenets. Process: Fast analytical ascent trajectory calculation and optimization resulting in vehicle payload performance. Output: Optimized trajectory evolution and payload mass.

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Loop 1

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 STS Design Process

Loop 2 Blue, dashed vectors: Resuable launch vehicles only Green: > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Blue, dashed vectors: Resuable launch vehicles only Green: Sleder-bodied expendable rockets only Loop 2

Loop 2 Loads and Structures: > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Loads and Structures: Analysis of tanks and structural shell elements considering specific load cases and internal pressurisation facilitates the sizing and mass estimation of these components. Stiffness and eigenfrequencies determined. Loop 2

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Ascent Control: Controllability of the launch vehicle is analysed during the ascent with influence from external forces, internal Center of Gravity movement and nozzle vector control. Loop 2

Infrastructure and Methods for STS Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Infrastructure and Methods for STS Design Distributive design environment Distribution Data Management Privilege Management Workflow Engine provide environment for coupling of tools to automated compute workflows. MDO, parameter studies. Platform Independence: executable on different operating systems.

Infrastructure and Methods for STS Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Infrastructure and Methods for STS Design Model-Based Systems Engineering The Common Parametric Aircraft Configuration Schema (CPACS) Describes the characteristics of aircraft and mission in a structured, hierarchical manner. Not only product but also process information.

Infrastructure and Methods for STS Design > CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Infrastructure and Methods for STS Design Object-Oriented Methods Time-dependancy Association Data base Programming practices applied to STS design

> CLaVA > Vanessa Clark • EUCASS > 01.07.2015 Conclusion The design of optimal, innovative and robust STSs poses a challenge for engineers and managers due to the complexity and sensitivity of the design parameters and disciplines! Design process gaps have been identified. Strengthening and guidance of the cooperation between discipline experts is required. The integration of the design process in a distributive environment and realisation of a central data model based on MBSE philosophies will be performed in subsequent activities.

questions? vanessa.clark@dlr.de > CLaVA > Vanessa Clark • Kick Off> 23.02.2015 vanessa.clark@dlr.de questions?