The design of small satellite propulsion systems is often a constant struggle to balance two opposing requirements: system performance and system safety. Cold gas thruster systems utilizing the refrigerant R-134a as a two-phase propellant have the potential to meet both the performance goals and safety requirements. This paper delineates a safety analysis for a general R-134a-based propulsion s...

One of the many challenges when it comes to small satellites is low cost, especially when it comes to propulsion. At Aerojet Rocketdyne a CubeSat propulsion system was developed utilizing the advantages of the additive manufacturing process. This design reduces the part count by 50%, eliminates all 22 final assembly welds and reduces the projected recurring propulsion system cost by 75%. Starti...

In this paper, a large scale Medium Voltage DC all-electric ship integrated power system is modeled from the prime mover (gas turbine) to the propulsion load. This system has a three-phase 21MW synchronous machine as a main generator and a three-phase 19MW induction motor as a main propulsion drive. The influence of propeller emergence on both electrical and mechanical components of the system ...

Scale down robots with propeller propulsion mechanisms are promising tools for minimally invasive surgery, diagnosis, targeted therapy, drug delivery and removing material from human body. Understanding the movement of micro robots inside fluid-filled channels is essential for design and control of reduced robots inside arteries and conduits of living organisms. Three-dimensional governing part...

The use of ion propulsion for deep-space missions will become a reality in 1998 with the  ight of the ion-propelled, New Millennium Deep Space 1 (DS1) spacecraft. The anticipation of this event is stimulating the call for improved ion propulsion technologies, a trend that is expected to continue. This paper describes the evaluation of possible advanced solar electric propulsion technologies an...

Recently conducted experiments at the University of Michigan and elsewhere have shown that ultrashort pulse (ultrafast) lasers could accelerate charged particles to relativistic speeds. For example a picosecond laser pulse with only one joule of energy can accelerate an electron to MeV energy in just a few microns distance. This takes place through the high gradient potential that manifests its...

The Gasdynamic Mirror (GDM) fusion reactor is investigated for utilization as a propulsion device, as well as for use as a surface power system when driven by antiprotons in both instances. The deuterium-tritium fusion reactions in the device will be initiated by the heating provided by the fission fragments and the annihilation products resulting from the “at rest” annihilation of antiprotons ...

The Ultrafast “Laser Accelerated Plasma Propulsion System” LAPPS makes use of lasers with very short pulse lengths to accelerate charged particles to relativistic speeds. Recent experimental data reveal that high intensity lasers are capable of producing collimated, charge-neutral proton beams containing more than 6 x 10 particles at a mean energy of 5 MeV with a total beam energy of 500J. If u...

This paper describes a methodology for design and optimization of a polymer electrolyte membrane (PEM) fuel cell unmanned aerial vehicle (UAV). The focus of this paper is the optimization of the fuel cell propulsion system and hydrogen storage system for a baseline aircraft. Physics-based models, and experimentally-derived sub-system performance data are used to characterize the performance of ...

This paper presents an efficient coil design for a mm-sized micro-robot which generates a propulsion force and torque and receives electrical energy using a wireless power transfer system. To determine the most efficient coil structures and produce propulsion and torque on the micro-robot, both helical and spiral coil modeling was conducted, and analytical formulations of the propulsion force a...