TRACTOR

https://youtu.be/6FGWwm7Rj6c

Overview

What is TRACTOR?

TRACTOR (Test Rig for Analysis and Control of Traveling Oscillations in a Resonant Beam) is a proprietary GMV dynamic surrogate platform that provides representative dynamics for the validation and maturation of Guidance, Navigation and Control (GNC) technologies for future space systems. Typical applications are In-orbit Servicing Assembly and Manufacturing (ISAM), with in-orbit assembly, large flexible spacecraft, and other missions involving complex structural dynamics.

TRACTOR has been engineered to provide a modular, configurable, and extensible capability for the development and verification of advanced control solutions. The platform reproduces key dynamic phenomena expected in future orbital infrastructures, such as flexible structural dynamics, bending modes, fluid sloshing, changing mass and inertia properties, and disturbances generated by robotic interactions.

TRACTOR has been developed within the IOANT project for client ESA.

Interested in assessing your GNC concept?

Contact GMV to discuss a tailored engineering demonstration based on the TRACTOR platform and explore how representative Hardware-in-the-Loop demonstrations can support your project [email protected].

What we offer

Customers can request tailored demonstration sessions to explore mission scenarios, evaluate GNC concepts and discuss engineering trade-offs with GMV specialists.

What you receive

The service combines live Hardware-in-the-Loop demonstrations with technical consultancy, allowing customers to better understand solution maturity, implementation approaches and integration aspects before entering a dedicated development programme

Characteristics

Representative dynamics:

Flexible structural dynamics
Bending modes
MCI variations
Robotic interaction disturbances
Propellant sloshing

Configurable elements:

Flexible beams
Robotic walker
Sloshing tank
Mission-specific payloads

Demonstration activities:

Control algorithm validation
Closed-loop hardware-in-the-loop
Algorithm benchmarking
Online estimation
System identification

Demonstration Environments:

MIL, SIL, PIL, Closed-Loop HIL
MATLAB / Simulink Digital Twin

Highlights

How does TRACTOR work?

Configurable Testbed for Representative In Orbit Scenarios

TRACTOR in double beam and sloshing configuration

The TRACTOR testbed is highly modular and can be configured to emulate a wide range of in orbit servicing, assembly, and manufacturing (ISAM) scenarios. Different flexible elements, as illustrated in the adjacent photographs, can be mounted to represent a variety of spacecraft appendages such as antennas, solar arrays, booms, and robotic structures.

By varying the beam geometry, material, and length, the platform can reproduce different structural stiffnesses and natural frequencies, exposing the control system to representative flexible body dynamics and disturbance environments. Both beams can also be equipped with travelling masses to emulate robotic manipulation and moving payload disturbances, while partially filled tanks can be incorporated to reproduce propellant sloshing effects.

These surrogate elements can be combined within a single experimental configuration, enabling realistic, coupled dynamic scenarios that support the development, validation, and maturation of advanced Guidance, Navigation and Control systems.

Robotic Walker for Dynamic Inertia and Disturbance Emulation

To reproduce the dynamic effects encountered during in orbit assembly and servicing operations, TRACTOR can be equipped with a robotic walker that traverses the length of the flexible beam. The moving mass acts as a surrogate for robotic manipulators, servicing vehicles, or translating payloads, introducing representative changes to the system dynamics throughout the operation. This capability enables the experimental validation of GNC algorithms under realistic time varying conditions, including:

Time varying mass properties, caused by changes in the overall mass distribution and moment of inertia as the walker moves along the structure.
Dynamic robotic interactions, resulting from the coupled motion between the flexible beam and the translating robotic walker, generating representative structural disturbances and vibrations.

This configuration provides a realistic environment for developing and validating control systems capable of maintaining stability and performance in the presence of changing system dynamics and robotic interaction forces.

Technology Readiness & Demonstrations

TRACTOR has been developed and experimentally validated as part of the ESA IOANT project, where its objective was to mature representative Hardware in the Loop platform for the development and validation of Guidance, Navigation and Control technologies for flexible space structures. Through an extensive experimental validation campaign, both the physical testbed and its accompanying digital twin have achieved Technology Readiness Level (TRL) 5, demonstrating their capability in a relevant laboratory environment.

The platform is fully operational and available for live demonstrations, technical evaluations, and proof of concept activities. Prospective customers and partners are invited to experience the platform's capabilities firsthand through demonstrations that can be tailored to their specific applications.

TRACTOR in external projects

The TRACTOR testbed and the technologies developed throughout the project have resulted in several scientific publications, conference papers, and technical contributions, presented below:

2023 CleanSpace Days: