ESA’s future space transportation programme, FLPP, has carried out a series of successful tests over the summer to evaluate different interfaces, developed by The Exploration Company, with Sener, GMV, Almatech, TAS-F and CDS of In-Space Proof-of-Concept (InSPoC)-1. The tests took place at ESTEC, ESA’s technical centre in the Netherlands and covered the full cycle of rendezvous, docking and refilling interconnect – a significant milestone for InSPoC.
The InSPoC venture is spearheading the development of an interoperable, in-space logistics ecosystem with shared and agreed-upon interfaces which meet the needs of a wide range of missions across the in-space value chain. To achieve this, InSPoC is derisking and demonstrating the foundational capabilities which will form the backbone of such an ecosystem.
“The objective is to design and demonstrate the interfaces that could enable an open in-space infrastructure allowing the supply of a wide range of services – as in-space mobility, dynamic orbital relocation, propellant refilling, and upgrade of assets – to the whole community of European space operators,” says Yann Tincelin, InSPoC Programme Manager at ESA.
InSPoC-1 tackles rendezvous, docking and transfer of fluids or gases between spacecraft. All elements of the interoperable interfaces need to be tested on the ground before their eventual use in space. Developing interoperable interfaces and rigorous testing are essential steps towards providing “à-la-carte” servicing for customers and ensuring the ecosystem can withstand the loads of tugs and in-space transportation.
However, before spacecraft can dock and refill, they must first reach their target location.”During a space rendezvous, a servicer spacecraft approaches its client matching its orbit and realising closing manoeuvres to reach it,” explains Lorenzo Pasqualetto-Cassinis, Guidance, Navigation and Control system engineer at ESA. These ongoing tests in the Guidance, Navigation and Control Laboratory (GNC) simulate the rendezvous and GNC-related interfaces of spacecraft from 300m.
“For this approach and rendezvous, we tested two camera systems in the laboratory that would enable this servicer to perform a vision-based navigation approach, bringing them from hundreds of metres apart to as close as a few centimetres in order to start docking,” adds Lorenzo Pasqualetto-Cassinis.
Multiple tests were undertaken to ensure the camera worked in all conditions, as Olivier Faure, Head of Future Projects & In-Orbit Services Programs at the Exploration Company comments, “This test allowed us to demonstrate the performances of our systems. The rendezvous must work in all conditions – in complete darkness, but also when the markers are reflecting sunlight and blinding the camera with flare. Similarly, the docking must work for multiple dynamic conditions in the last centimetres, with a range of relative positions and velocities with the target. The tests were instrumental for us to get a better understanding of how our system will perform before we test it in space.”
Having achieved rendezvous, the docking and refilling interfaces test campaign commenced in ESA’s Orbital Robotics Laboratory.
“In this part of the testing, the servicer and client satellite models are each attached to one floating platform,” says Jules Noirant, ESA’s automation and robotics engineer. “The servicer-simulating platform weighs around 180 kg and has an additional 20 kg weight attached on either side to simulate an inertia ratio with the client similar to a real-life scenario.”
Using its navigation algorithm, and starting at four centimetres apart from the client, the servicer’s docking mechanism detects the position of the passive capture interface, encloses it with its gripper (soft capture) then proceeds to the mechanical coupling of the two (hard capture). The two servicing ports – one for refuelling and the other for power and data transfer – then connect with their counterpart.
The process met the requirements of the technical readiness review, meaning all stages of rendezvous, docking and refilling have been demonstrated this summer.
ESA is leading the way in working with industry and partners across Europe to build a resilient, cooperative and connected space ecosystem, mapping future needs and identifying the developments essential to achieving the goal of a sustainable, circular space sector – a sector that is advancing exploration and transportation in space while protecting life on Earth.
Find out more about InSPoC’s groundbreaking work in shaping the space ecosystem and how your business could work with ESA and join the journey to a more sustainable future.
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