Design of Ultralight Inflatable Antenna for Low Earth Orbit: Lorentz Force-Based Orientation Feasibility study

This thesis investigates the preliminary feasibility study of a new class of ultra-light inflatable antennas with a large transmitting and receiving surface composed of metallized fabric. These antennas are designed for deployment in Low Earth Orbit (LEO), at approximately 2000 km altitude from sea level. The orientation is controlled through the interaction between the Earth’s magnetic field and electric currents induced within conductive elements embedded in the antenna’s structure. This innovative control method eliminates the need for traditional mechanical actuators or booms, reducing complexity, mass, and transportation cost to space, while increasing operational efficiency. A critical challenge associated with inflatable antennas is deployment and ensuring structural integrity of the membrane. Historical NASA experiments with inflatable space antennas were conducted in the 20th century, revealing a high failure rate due to uncontrolled inflation in vacuum conditions, leading to sudden structural collapse. This thesis addresses these concerns by conducting a pre-feasibility study on suitable materials specifically selected, inflation techniques, and rigidization methods. The selected inflation strategy ensures safe and controlled deployment, while rigidization mechanisms provide long-term structural stability, reducing the effects of micrometeoroid impacts and material degradation over time. In addition to structural considerations, this work explores power generation solutions necessary for antenna operation. Advanced photovoltaic technologies, including new generation lightweight and flexible solar cells, are evaluated as a means of supplying power to the system. These solar cells can be integrated onto the antenna’s surface or deployed on an auxiliary CubeSat operating in proximity to the antenna, enabling wireless energy transfer and improving mission sustainability. The inflatable antenna structure is designed as a spheroid, with the southern hemisphere forming a parabolic reflective surface composed of metallized fabric, while the northern hemisphere remains transparent to electromagnetic radiation. The proposed system holds significant potential for aerospace applications, including radio astronomy and deep-space communication. Through structural simulations, material selection studies, and power system evaluations, this thesis lays the groundwork for further development of inflatable antennas for space applications. While the findings confirm the feasibility of this innovative concept, additional experimental validation and optimization are required to transition from theoretical analysis to practical implementation in orbit.