ISBN 9783843915762

978-3-8439-1576-2, Reihe Raumfahrt

Markus Pietras
End-to-End Simulation of Teleoperated On-Orbit Robotics

301 Seiten, Dissertation Technische Universität München (2014), Softcover, A5

Zusammenfassung / Abstract

This thesis presents the development and implementation of an end-to-end simulation environment for robotic space missions. The 'Robotic Actuation, Control, and On-Orbit Navigation Simulator', RacoonSim, is designed for enhancing the development of new technologies and strategies in space robotics. It allows testing of both teleoperated and autonomous robotic scenarios at each development stage. Hence, proof of concept simulations at very low system definition level are possible as well as closed loop verification tests and optimizations of design details.

The challenges of such a simulation environment are twofold: Due to the complex nature of dexterous robotic operations in the close proximity of sensitive target systems, human factors, situation awareness and performance of the human control team can have a significant impact on the mission. Hence, the implementation of all technical and environmental features of on-orbit robotics is required without overstretching computational performance and maintaining real-time executability. This includes the representation of all mission segments and of environmental and system intrinsic properties. In addition, a highly adaptable software architecture and model interpretation method is required that is able to represent a high diversity of currently even unknown scenarios and systems.

In order to counter those challenges, an analysis and decomposition of on-orbit robotics missions is performed in order to identify reusable, functional abstractions of characteristic elements. Those functions are implemented within a modular software architecture with highly specialized and optimized core engines for individual computational tasks. A dedicated physics module handles multi-body dynamics, surface contacts and collisions and mechanical constraints. An on-board control simulation module provides an environment for Rapid Control Prototyping and low-level subsystem representation. Visual feedback of different camera perspectives is realized by a 3D rendering engine. Telecommands are transmitted from a dedicated, adaptable Man-Machine Interface.

The simulation concept is demonstrated by three exemplary simulations comprising a high diversity of mission types and spacecraft systems: A manually teleoperated robotic capture of a large satellite, a pre-planned fly-around inspection by a light weight freeflyer and autonomous docking with a spinning and nutating target.