초록 ▼

An axial electrostatic ion thruster for use on a dual-spin stabilized spacecraft is disclosed. The thruster is mounted on the spun portion of the spacecraft and continuously fired for an integral number of spin periods to provide north-south velocity and attitude control. To achieve zero attitude pr

An axial electrostatic ion thruster for use on a dual-spin stabilized spacecraft is disclosed. The thruster is mounted on the spun portion of the spacecraft and continuously fired for an integral number of spin periods to provide north-south velocity and attitude control. To achieve zero attitude precession with a statically imbalanced despun platform, or an intentional attitude precession generally, the ion thrust is spin-synchronously varied between two non-zero levels to achieve a prescribed Fourier component amplitude and phase at the spin frequency. Modulation of the thrust is achieved with constant ion beam current by complementary modulation of the beam voltage, VB, and accel voltage, VA by varying the ion extraction system grid voltages. This varies the thrust while maintaining a constant total accelerating voltage VTOT=VB+│VA│.

대표청구항 ▼

An electrostatic ion thruster with thrust modulation comprising: means for providing a gaseous propellant; means for ionizing said gaseous propellant to generate a plasma; means for containing said plasma; an ion extraction assembly for extracting a beam of positively charged ions from said plasma,

An electrostatic ion thruster with thrust modulation comprising: means for providing a gaseous propellant; means for ionizing said gaseous propellant to generate a plasma; means for containing said plasma; an ion extraction assembly for extracting a beam of positively charged ions from said plasma, said extraction assembly including a screen electrode and an accel electrode, said screen electrode being positioned between said accel electrode and said plasma; and voltage control means for complementary modulation of the voltage potentials of said screen electrode and said accel electrode such that a substantially constant potential difference is maintained therebetween; whereby a relatively constant ion beam current is maintained while the thrust from said ion thruster is modulated.