# Inflation deployed torus-shaped solar sail accelerated via thermal desorption of coating

## TL;DR

This paper proposes a novel torus-shaped solar sail design that uses thermal desorption of a heat-sensitive coating to deploy and accelerate the sail via combined thermal desorption and solar radiation pressure, with analysis of stability and dynamics.

## Contribution

It introduces a new deployment and acceleration method for solar sails using thermal desorption of a coating, combining inflation and solar radiation pressure for propulsion.

## Key findings

- Successful conceptual design of the torus-shaped sail deployment process.
- Analysis of stability and vibration during acceleration.
- Feasibility of using thermal desorption for sail acceleration.

## Abstract

A torus-shaped sail consists of a reflective membrane attached to an inflatable torus-shaped rim. The sail's deployment from its stowed configuration is initiated by introducing inflation pressure into the toroidal rim with an attached circular flat membrane coated by heat-sensitive materials that undergo thermal desorption (TD) from a solid to a gas phase. Our study of the deployment and acceleration of the sail is split into three steps: at a particular heliocentric distance a torus-shaped sail is deployed by a gas inflated into the toroidal rim and the membrane is kept flat by the pressure of the gas; under heating by solar radiation, the membrane coat undergoes TD and the sail is accelerated via TD of coating and solar radiation pressure (SRP); when TD ends, the sail utilizes thrust only from SRP. We study the stability of the torus-shaped sail and deflection and vibration of the flat membrane due to the acceleration by TD and SRP. The stability of the toroidal rim is addressed.