Session

Technical Session 7: Advanced Technologies I

Location

Utah State University, Logan, UT

Abstract

This paper describes the third iteration in the development of a simulation tool that provides trade-offs of avionic architectures for future Active Debris Removal (ADR) space missions.

The principle of ADR mission is to target an object in space and move it somewhere else, preferably by deorbiting it. The initial task of the satellite (chaser) is to detect and track the targeted debris or object, then perform some proximity operations before capturing it. Associated with each phase, there is a couple of unique challenging mainly linked to the uncooperativeness of the target. To handle these problems, the chaser must embark a variety of sensors for the Guidance, Navigation, and Control (GNC). It must equally have multiple dedicated algorithms for pose and attitude estimations of the target. To obtain accurate information, the algorithms require a high input data rate and from multiple sensor sources. The first one guarantees constant tracking and the second prevents any biasing. Furthermore, because of orbital mechanisms and potential low ground coverage, data have to be analyzed on-board to satisfy a constant feed of the algorithms.

The simulator developed by the EPFL Space center focuses on the optimization of avionic architectures for ADR missions such as ClearSpace-1 (CS-1)∗. The current version uses an Optimal Control (OC) approach by considering a mathematical model of the architecture. Its primary purpose is to minimize the number of elements used in the avionic and optimize its output in terms of accuracy on target detection and tracking. The model contains descriptions of the sensors and the algorithms. It additionally includes information on the On-Board computer as well as the connection between the various elements. The process is to run specific scenarios over time with varying constraints like power consumption. The optimizer will try guessing the ideal configuration of algorithms and sensors given the current constraint and the objective function. The latter dictates the most critical parameters to optimize in the simulation.

To considerably increase the representativeness of the simulation tools, the team has been focusing on the improvement of the mathematical model. This novel approach addresses various issues encountered during the previous versions. It can better simulate the flow of information through the architecture and considers multiple types of data. In the current model, the simulator can run algorithms at various speeds and employs specific links between them and the sensors with some memories. This publication also introduces a broader variety of scenarios. Emphasis has been made on comparing one architecture with multiple scenarios. A parametric analysis approach has been employed to better comprehend the importance of each parameter.

The EPFL Space Center is operating this tool to investigate multiple hardware configurations with specific ADR requirements for ClearSpace-1. Its design can help to create preliminary scenario plans by optimizing the avionic architecture of the satellite. In addition, it provides some initial assessment of the requirements needed for the high-performance On-Board Computer.

Available for download on Saturday, August 07, 2021

Share

COinS
 
Aug 10th, 12:00 PM

Optimal Control Approach for Dedicated On-Board Computer in Active Debris Removal Mission

Utah State University, Logan, UT

This paper describes the third iteration in the development of a simulation tool that provides trade-offs of avionic architectures for future Active Debris Removal (ADR) space missions.

The principle of ADR mission is to target an object in space and move it somewhere else, preferably by deorbiting it. The initial task of the satellite (chaser) is to detect and track the targeted debris or object, then perform some proximity operations before capturing it. Associated with each phase, there is a couple of unique challenging mainly linked to the uncooperativeness of the target. To handle these problems, the chaser must embark a variety of sensors for the Guidance, Navigation, and Control (GNC). It must equally have multiple dedicated algorithms for pose and attitude estimations of the target. To obtain accurate information, the algorithms require a high input data rate and from multiple sensor sources. The first one guarantees constant tracking and the second prevents any biasing. Furthermore, because of orbital mechanisms and potential low ground coverage, data have to be analyzed on-board to satisfy a constant feed of the algorithms.

The simulator developed by the EPFL Space center focuses on the optimization of avionic architectures for ADR missions such as ClearSpace-1 (CS-1)∗. The current version uses an Optimal Control (OC) approach by considering a mathematical model of the architecture. Its primary purpose is to minimize the number of elements used in the avionic and optimize its output in terms of accuracy on target detection and tracking. The model contains descriptions of the sensors and the algorithms. It additionally includes information on the On-Board computer as well as the connection between the various elements. The process is to run specific scenarios over time with varying constraints like power consumption. The optimizer will try guessing the ideal configuration of algorithms and sensors given the current constraint and the objective function. The latter dictates the most critical parameters to optimize in the simulation.

To considerably increase the representativeness of the simulation tools, the team has been focusing on the improvement of the mathematical model. This novel approach addresses various issues encountered during the previous versions. It can better simulate the flow of information through the architecture and considers multiple types of data. In the current model, the simulator can run algorithms at various speeds and employs specific links between them and the sensors with some memories. This publication also introduces a broader variety of scenarios. Emphasis has been made on comparing one architecture with multiple scenarios. A parametric analysis approach has been employed to better comprehend the importance of each parameter.

The EPFL Space Center is operating this tool to investigate multiple hardware configurations with specific ADR requirements for ClearSpace-1. Its design can help to create preliminary scenario plans by optimizing the avionic architecture of the satellite. In addition, it provides some initial assessment of the requirements needed for the high-performance On-Board Computer.