How Space Taxis and Locomotives Move Satellites Between Orbits

A modular system using a small 'rendezvous' vehicle to collect satellites and a larger 'locomotive' vehicle to haul them to their final destination in space.

What it covers

This patent describes a two-part space transport system designed to move satellites between different orbits efficiently. A small, nimble 'rendezvous vehicle' travels to a satellite's current location, docks with it, and brings it to a larger 'locomotive vehicle' already waiting in orbit. Once connected into a single stack, the locomotive uses its more powerful propulsion system to move the entire assembly to the satellite's target orbit. Finally, the satellite is released to begin its mission. The system is designed to share propellant between the vehicles, allowing for longer missions and more flexibility in how satellites are deployed.

What it doesn't cover

• —Does not cover single-stage orbital transfer vehicles that move satellites without docking to a secondary locomotive.
• —Does not cover ground-based launch systems or rockets used to initially put satellites into orbit.
• —Does not cover autonomous docking systems that do not specifically utilize the rendezvous-to-locomotive stack architecture.
• —Does not cover propulsion systems that do not use the specified ammonia propellant configuration.

The clever bit

The innovation lies in decoupling the 'last mile' delivery (the rendezvous vehicle) from the 'long haul' transit (the locomotive), and specifically enabling the transfer of propellant between these vehicles to extend their operational life.

Why it matters

As the number of satellites in orbit increases, moving them to specific, optimal locations becomes expensive and fuel-intensive. This patent provides a blueprint for a 'space tug' infrastructure, potentially reducing the need for every satellite to carry its own massive fuel supply. It represents a shift toward treating space as a logistics network rather than a series of one-off rocket launches.

Real-world examples

• 1.Orbital transfer vehicles (OTVs)
• 2.Space tug infrastructure
• 3.Satellite servicing missions