ESTCube-1 nanosatellite for electric solar wind sail in-orbit technology demonstration

摘要

This paper presents the mission analysis, requirements, system design, system level test results, as well as mass andpower budgets of a 1-unit CubeSat ESTCube-1 built to perform the first in-orbit demonstration of electric solar wind sail (E-sail)technology. The E-sail is a propellantless propulsion system concept that uses thin charged electrostatic tethers for turning themomentum flux of a natural plasma stream, such as the solar wind, into spacecraft propulsion. ESTCube-1 will deploy and chargea 10 m long tether and measure changes in the satellite spin rate. These changes result from the Coulomb drag interaction with theionospheric plasma that is moving with respect to the satellite due to the orbital motion of the satellite. The following subsystemshavebeendevelopedtoperformandtosupporttheE-sailexperiment: atetherdeploymentsubsystembasedonapiezoelectricmotor;an attitude determination and control subsystem to provide the centrifugal force for tether deployment, which uses electromagneticcoils to spin up the satellite to one revolution per second with controlled spin axis alignment; an imaging subsystem to verify tetherdeployment, which is based on a 640ud ×ud 480 pixel resolution digital image sensor; an electron gun to keep the tether at a highpositive potential; a high voltage source to charge the tether; a command and data handling subsystem; and an electrical powersubsystem with high levels of redundancy and fault tolerance to mitigate the risk of mission failure.