Skip to content
In-Orbit Refueling Ecosystem Who • Why • What of IOR

In-Orbit Refuelling
Initiative (IORI)

Enabling companies to build their respective parts of an In-Orbit Refueling ecosystem by providing system requirements, designs, system-level specifications, interfaces, QA frameworks, and guidelines.

Ensuring independently developed components work together as a coherent, interoperable, and comprehensive system.

IOR Initiative Work Explore FAQ
In-Orbit Refueling Earth View

Why is IORI Needed?

Addressing the gap in end-to-end refueling systems coordination.

The Requirement

In-orbit refueling requires multiple independently developed elements to work together:

  • Service Vehicles performing rendezvous, docking, and propellant transfer
  • Client spacecraft receiving propellant
  • Orbital depots storing and managing propellant
  • Resupply missions delivering propellant to orbit
  • Ground systems coordinating planning, authorization, and execution

The Current Reality

Today, these elements are being developed in isolation:

  • Refueling systems without common interface definitions
  • RPOD capabilities without system-level integration
  • Depot and resupply concepts without coordinated operations

The Gap

There is no unified framework that defines:

  • How Service Vehicles interact with client spacecraft
  • How propellant flows from Earth → depot → client
  • How operations are coordinated across multiple organizations
System Technology Space View

What We Do

The In-Orbit Refueling Initiative (IORI) enables companies to build their respective parts of an IOR ecosystem by providing:

  • System requirements & System designs
  • System-level specifications
  • Interfaces (IRD, ICDs)
  • QA frameworks & Implementation guidelines

The effort ensures that independently developed components work together as a coherent, interoperable, and comprehensive IOR system.

System Interfaces

  • Service Vehicle ↔ Client Spacecraft
  • Depot ↔ Service Vehicle
  • Resupply Vehicle ↔ Depot
  • IOR supplier Ground Segment ↔ Client Operator Ground Segment
  • IOR supplier Ground Segment ↔ Service Vehicle, Depot

Technology Interfaces

  • Sensor/Lidar/Camera ↔ Service Vehicle
  • ADCS/Propulsion ↔ Spacecraft

Who is it For?

IORI is intended for organizations across the IOR ecosystem:

  • Organizations: IOR service providers, Satellite, Depot and service vehicle manufacturers, Constellation operators
  • Technology Vendors: Trajectory/mission design, RPOD, LiDAR/sensor, Propellant/fueling tech providers
  • Supporting Companies: Resupply and Launch providers

Expected Outcome

An open IOR infrastructure where multiple players come together to economically deliver propellant in space.

  • LEO, MEO, GEO
  • Space stations
  • Cislunar missions

The intent is to enable a scalable and commercially viable refueling ecosystem through standardized interfaces and coordinated system-level integration.

How We Work

IORI brings companies together and aligns efforts across the existing ecosystem, building on work from:

  • CONFERS & IRSIS
  • Satellite Applications Catapult
  • Learnings from AIAA, ESA and NASA
  • Broader aerospace refueling practices

About IORI

IORI connects independently developed systems into a coherent system-level framework that supports:

  • System architecture definition
  • Interface and requirements development
  • QA and compliance frameworks
  • End-to-end system engineering support

Frequently Asked Questions

Everything you need to know about the initiative.

This IOR initiative is a systems engineering architecture study focused on in-orbit refueling (IOR). It structures the problem from mission context and operational scenarios through to system architecture. The objective is to create a common framework that brings together ISAM/RPOD providers, satellite manufacturers, and constellation operators to enable a more standardized refueling ecosystem. We also support companies in aligning their systems with the IOR framework through systems engineering, embedded software development, and verification and certification support.
No. It defines system-level architecture and interfaces so companies can build their own components.
Organizations building or operating parts of the IOR ecosystem including service vehicles, depots, satellites, RPOD technologies, and resupply systems.
We review and follow CONFERS and IRSIS, and build on top of efforts from these organizations. It connects them at the system level to enable interoperability.
Lack of coordination between independently developed systems, ensuring components from different providers work together reliably.
Membership is free and by invitation. Please email iori@inorbitrefueling.org with your company details, area of interest, and intended participation.

Let's Shape the Future Together

Join the In-Orbit Refueling Initiative today.

Contact IORI