Solid-State Oxygen Ion Propulsion for Nano-Satellites

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current propulsion systems for small space vehicles, such as nano-satellites, face challenges in miniaturization, particularly in the fabrication of leak-tight micro-valves for cold gas blow-down rocket engines, leading to undesired disturbance torques and short mission duration due to high leak rates and complexity.

Innovation Solution

A propulsion apparatus featuring a stack with a solid state oxygen-rich source layer and an active layer exhibiting impedance hysteresis behavior, where the active layer is formed with a resistive switching material, allowing for controlled oxygen ion extraction and acceleration using a cross-bar array architecture and metallic layers, with nozzles and an ion accelerating element for efficient thrust generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If miniaturized propulsion systems are used for nano-satellites, then the vehicle size is reduced, but the fabrication of leak-tight micro-valves becomes technologically challenging and complex

Engineering Contradiction:
Improvevehicle sizeVSAvoidmicro-valve fabrication complexity
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical micro-valve system with a solid-state ion conductor-based electrochemical oxygen extraction system. The YSZ membrane electrode assembly enables oxygen extraction through electrochemical reactions rather than mechanical valve control, eliminating the complex micro-valve fabrication requirements while maintaining miniaturization benefits for nano-satellite propulsion.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Volume of moving object

If micro-valves are downsized to comply with miniaturization demands, then the device size is reduced, but the leak rate increases causing undesired disturbance torques and shortening mission duration

Engineering Contradiction:
Improvedevice sizeVSAvoidleak rate control
Core Design Contradiction:
Volume of moving objectVSReliability

Solution Approach 1:

The patent eliminates mechanical valve structures entirely by using a solid-state electrochemical oxygen extraction mechanism. The YSZ membrane provides inherent leak-tightness through its solid-state ion-conducting properties, preventing gas leakage and disturbance torques while maintaining compact device dimensions suitable for miniaturized satellite propulsion systems.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Quantity of substance

If YSZ is heated to about 1000 K to operate as oxygen reservoir, then oxygen permeability is improved, but reliability and cost are compromised due to high temperature operation

Engineering Contradiction:
Improveoxygen permeabilityVSAvoidreliability at high temperature
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent modifies the operating parameters by using a solid-state oxygen reservoir that does not require heating to 1000 K. The YSZ membrane electrode assembly operates at lower temperatures through electrochemical oxygen extraction mechanisms, changing the thermal parameter from high-temperature thermal diffusion to low-temperature electrochemical reactions, thereby improving reliability while maintaining oxygen supply.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs a composite structure combining YSZ membrane electrode assembly with solid-state oxygen reservoir materials. This composite approach enables oxygen extraction at lower temperatures by utilizing the electrochemical properties of the YSZ composite system rather than relying on high-temperature thermal diffusion of pure YSZ, thus improving reliability and reducing thermal stress.

Inventive Principle:
Principle #40Composite materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution provides a reliable, efficient, and compact propulsion system with high thrust-to-weight ratio, long duty-cyclability, and precise control over oxygen expulsion, suitable for small satellites, offering improved reliability and safety compared to existing technologies.

Implementation Method 1

an active layer being deposited above said solid state oxygen-rich source layer, in contact with said solid state oxygen-rich source layer, said active layer being formed with a material different from said solid state oxygen-rich source layer, said material being an oxide featuring impedance hysteresis behavior

Methodology Applied
Scientific EffectImpedance hysteresis behavior: Hysteresis

Implementation Method 2

the active layer being formed with a resistive switching material, allowing for controlled oxygen ion extraction

Methodology Applied
Scientific EffectResistive switching: Electrical Resistance

Implementation Method 3

a heating electrode associated to the solid sate oxygen-rich layer

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 4

means for accelerating correspondingly extracted oxygen ions into vacuum

Methodology Applied
Scientific EffectIon acceleration: Electrostatics

Data Source

PatentEP3384158B1Propulsion apparatus for space vehicles and corresponding method
Publication Date: 2020.12.23 FOND INST ITAL DI TECH
  • EP3384158B1 patent drawingFigure 1A~1F
  • EP3384158B1 patent drawingFigure 2A~2F
  • EP3384158B1 patent drawingFigure 3~4

AI summary

Propulsion apparatus (10) for space vehicles, comprising a solid state oxygen-rich source layer (11), means (12) for extracting oxygen from said solid state oxygen-rich source layer (11), means (16, 14, 17) for accelerating correspondingly extracted oxygen ions into vacuum. According to the invention, it comprises a stack including said solid state oxygen-rich source layer (11), an active layer (16) being deposited above said solid state oxygen-rich source layer (11), in contact with said solid state oxygen-rich source layer, said active layer (16) being formed with a material different from said solid state oxygen-rich source layer (11), said material being an oxide presenting impedance hysteresis behavior, i.e. a memristor, wherein in a low resistance state oxygen ions (22) are expelled through the active layer (16) and wherein in a high resistance state the active layer (16) ceases expelling oxygen ions (22).