Spacecraft Propulsion Arm Joint Failure Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The increased complexity of articulated propulsion arms in spacecraft attitude and orbit control systems makes it difficult to detect and isolate joint failures, as the number of potential failure points increases, and existing methods require multiple dedicated sensors.

Innovation Solution

A method that uses existing sensors like gyroscopes and accelerometers to estimate the spacecraft's rotational speed, calculate the angular momentum residue, and project it onto a fault isolation space to detect joint failures, reducing the need for additional sensors and allowing for the detection and isolation of joint and thruster failures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If dedicated sensors are installed at each joint level to detect failures, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improvejoint failure detection precisionVSAvoidsensor quantity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies multi-functionality by enabling existing attitude and orbit control sensors (gyroscopes, accelerometers) to serve dual purposes: both controlling the spacecraft's attitude/orbit and detecting propulsion arm joint failures. This eliminates the need for separate dedicated sensors at each joint, thereby maintaining measurement precision while reducing device complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system performs self-diagnosis by using its own existing sensors to detect faults within the propulsion arm system. The attitude and orbit control sensors monitor for parasitic torques and angular position errors that indicate joint failures, allowing the system to self-detect and self-isolate faults without requiring external dedicated sensing equipment.

Inventive Principle:
Principle #25Self-service

2Adaptability or versatility

If the number of joints in the propulsion arm is increased to improve control precision, then adaptability is improved, but device complexity increases

Engineering Contradiction:
Improvecontrol operation adaptabilityVSAvoidnumber of failure points
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent makes the existing sensor system universal by configuring it to detect failures across multiple joints of the propulsion arm. The same attitude and orbit control sensors monitor for failures in any joint, allowing the system to maintain adaptability with multiple joints while avoiding the complexity increase that would result from adding dedicated sensors to each joint.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP3294631B1Method and system for detecting a breakdown in a propulsion arm of a spacecraft such as a satellite
Publication Date: 2019.03.13 AIRBUS DEFENCE & SPACE SAS
  • EP3294631B1 patent drawingFigure 1~2
  • EP3294631B1 patent drawingFigure 3a~4
  • EP3294631B1 patent drawing

AI summary

The present invention relates to a method (50) for detecting a breakdown of a propulsion arm (20, 21) comprising a thruster (30, 31) and an articulation (22, 23, 24), said propulsion arm being able to form a pair which, in one status of the propulsion arm, is connected by a pair formation function. Said method involves: - calculating (51) a fault isolation space, associated with the articulation of the propulsion arm, according to the gradient of the pair formation function, - estimating (52) a rate of rotation of the spacecraft (10), - estimating (53) a residual kinetic moment of the spacecraft, - calculating (54) a joint residual associated with the articulation of the propulsion arm by projecting the kinetic moment residual onto the fault isolation space, - searching (55) for an articulation breakdown on the basis of the articulation residual.