PLUGIN Concept Structure


The PLUGIN project aims at developing an open standard for hosting innovative technology packages as passenger payloads on-board commercial satellites. It proposes a simple generic approach, including technical interface requirements and implementation schedule from delivery to the clean room, integration, launch and flight operations. PLUGIN will also define the business model for hosting such payloads on commercial spacecraft and associated contracting principles, together with a list of flight opportunities. The PLUGIN consortium consists of Airbus DS (Lead), SSTL UK and ISIS. The study duration is 18 months.

The study has been divided into two parallel branches:

  1. The development of the interface requirements from a technical, operational and programmatic point of view. For this, passenger representatives, i.e. the developers of the payloads potentially interested in “piggybacking” a GEO host satellite were invited to discuss the needs and constraints from their side in three separate workshops:
  • Workshop 1: higher level system requirements of such a standardized interface.
  • Workshop 2: subsystem requirements.
  • Workshop 3: integration and test, flight and operational topics.
  1. The development of the business model, contracting principles and implementation schedule.
    With the knowledge of primes about current GEO satellite manufacturing programs the large operators are contacted.

The PLUGIN project is structured around an Advisory Group and a Passenger Representative Panel.

  • The Advisory Group will help the PLUGIN team to propose solutions commercially and technically acceptable by the various stakeholders of the industry. Participants are ESA, Telecom satellite operators and insurers.
  • The Passenger Representative Panel (PRP) focuses on technical and program interfaces, such as integration, testing, launch and operations. The panel includes space hardware manufacturers from various European countries. Research labs, large companies and SMEs are welcome to join PRP.

PLUGIN outcomes will be made public and available to the whole European Industry to promote the further development and adoption of a generic standard.

Concept structure

The PLUGIN concept defines a set of interfaces as a standard to IOD/IOV hosted payload candidates for flight. The broad scope of IOD/IOV technologies can be divided into three categories: Small, Medium and Large payloads. The categorization is explained in the Figure below.

Why standardize?

Standardization can bring down costs and risks. However, considering the broad range of IOD/IOV technologies the approach “one size fits none” was considered the best. To cover all possible payload requirements, the standard has been divided for two categories of payloads: large and medium on one hand, and small payloads on the other hand.

This categorization leads to the definition of two standard interface units/functions:

Hosted Payload Interface Unit (HPIU)

    being used as:

  • A direct interface for medium and large category IOD/IOV hosted payloads


  • In combination with the Hosted Payload Container (HPC) for accommodating small / low-medium category IOD/IOV hosted payloads


Technical documentation

Over the course of three workshops, the PRPs and the Advisory group discussed and concluded on several technical aspects, namely: power, data, mechanical interfaces, amongst others. The following technical documentation has been prepared:

  • Interface Requirements Document for Hosted Payload on-board GMPT SSTL & E3000 Airbus DS platforms

Status: issue 2 rev0 released on the 23rd of May 2016

  • Hosted Payload Interface Unit (HPIU) Technical Specification

Status: Draft released July 2015, currently being updated

  • PLUGIN Hosted Payload Container Interface Specification Document

Status: issue 1_draft5 released on the 18th of December 2015

Host platforms

Hosted P/L interface overview

E3000 and GMP-T platforms were considered as a starting point to elaborate the PLUGIN standards. They will be transposed to next generation of Eurostar platform and GMP platform as well.

  Current host platforms within PLUGIN standard Potential extensions to other host platforms
E3000 / Alphabus
 other-prime  other-primes
Manufacturer Airbus SSTL Other primes
Mass Envelope Up to 150 kg Up to 50 kg    
Volume Depending on primary P/L 0.4 x 0.4 x 0.4m    
Supported mission life 3 years typical, up to 15 years 3-4 years typical, up to 15 years    
Location on host Earth facing, anti-earth possible in specific configuration Earth facing, or other view by sensors on boom    
Power (BOL)
  • <750 W @ 50V SBVR
  • No limit @ 100V
<500 W    
Voltage 100, 50 and 28V 46.5 – 52.5 V reg.    
Attitude control Beam pointing error: 0.08° @ 99,7% Beam pointing error: 0.1° @ 99,7%    
Data interfaces LSSB, CAN,1533 bus, RadCan, HPIU (optional)
  • 1553 bus or RadCan
  • U: 500kbps
  • D: 8Mbps
Thermal Control Passive or active depending on primary P/L Passive or active depending on primary P/L    


Hosted Payload interface Unit Hosted Payload Container
Application Interface direct to host for medium and large payloads Container for small payloads; needs to be used in combination with HPIU
Conops hosted P/L
  • Fixed in or on satellite
  • Fixed in or on satellite
  • Exposable
Mass Envelope Depending on host Up to 32 kg
Volume Depending on host 0.2 x 0.2 x 0.3m
Supported mission life 3-4 years typically, but lifetime depending on the host platform 3-4 years typically, but lifetime depending on the host platform
Power (BOL) Depending on host Depending on host
Voltage 50V and 28V 50V, 28V or lower if converter is applied
Attitude control Depending on host Depending on host
Data interfaces CAN,1533 bus, Spacewire Can, 1553 bus, space wire
Data upload/ Download Through host links

U: few kbps

D: few kbps

Through host links

U: few kbps

D: few kbps

Thermal Control Passive or active depending on primary P/L Passive or active depending on primary P/L