Satellite Servicing: Inspexity's Autonomous Space Mechanic

In-Orbit Rejuvenation: Satellite Servicing

When a satellite runs out of fuel, it becomes dead weight, tumbling at over 27,000 kilometers per hour, or drifting in orbit until it falls to Earth. The entrepreneurs behind Indian startup Inspexity want to give satellites a second lease on life. Instead of drifting into space junk. Instead of hoping for the satellites' crash landing years or even decades later, they are building the space equivalent of a mechanic on the end of a robotic arm. In-space servicing is the process of repairing or refueling satellites. The goal is to keep valuable satellites operational and avoid clutter of dead satellites in orbit. Though satellites can cost millions of dollars and have a lifespan of 15 years, there's no way to refuel them once in orbit. Inspexity plans to change this.

The Orbital Economy and Satellite Servicing in Space

The gravitational pull of Earth takes down all matter, but it can only grab things if they are moving slow enough. When satellites exceed that speed, they orbit the planet perpetually. This is great for telecommunications and scientific instruments, but problematic for spacejunk. Humans add to the amount of space junk each time we launch a rocket or a satellite. There's no practical way to collect this floating trash (at least from Earth). But some companies are developing new ways to solve this problem. Servicing that satellite debris in orbit will decrease the danger of space junk, but also turn these satellites into new profit centers. The goal is to help satellites — especially high-value ones — stay in action longer.

The Mechanics of In-Orbit Rescue

Inspexity aims to turn dead satellites into assets of the new orbital economy using a robotic mechanic. How do they plan to approach a target tumbling at 27,000 kilometers per hour?

Space's Most Dangerous Job

Imagining the space mechanic's task is like trying to grab a tiny nut from a high-speed drill with pinchers. The mechanic might be eight miles away; the target could easily be flung to the opposite side of the planet in an instant. Furthermore, using any kind of reference GPS is "completely useless" for a safe approach in space. Simply put, there are no roads in orbit and the mechanic can't rely on Google maps.

Mapping the Target

The space mechanic uses onboard lasers and optical cameras to map the satellite's exact distance, orientation, and spin rate. This is the first step toward that precise grab. Sensors constantly communicate with the target, sending this information back to the mechanic. The technician knows the targets' chaotic tumbling velocity and changes its own speed and direction accordingly and synchronizes.

Grabbing the Satellite

The multi-jointed robotic arm extends onto to grasp its prey. This arm struggles to smooth out any chaotic tumbling, because the target is moving so quickly. This perfect match of both ship velocities is the only way to make contact. It does so with the help of precise thruster bursts. Otherwise, the mechanic won't be able to latch onto the chassis like it does in the video. The thruster bursts help to match the tumbling velocity of the satellite.

Satellite Servicing on Earth vs. Orbit

Satellites are serviced on Earth every day, but satellite servicing in orbit is a different story. The International Space Station has repaired itself over the years, such as a space walk to replace a camera. But there's a difference between a camera and an 11-ton satellite. NASA attempted satellite servicing a few times — to an aging solar telescope and a communications satellite — but those were merely experiments. Given these examples, it's clear that in-orbit satellite servicing is fraught with challenges. While Inspexity's plan looks tough, it is potentially the future of orbital astronomy. Not only does it help prevent spacejunk, but it also can bring satellites back into service and create new commercial opportunities.