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Deployable composite booms are particularly attractive in space constrained applications. Their high packaging volume efficiency enables relatively large spacecraft systems required for power generation, communications, or propulsion to be housed within small volumes. COROTUB is a monolithic closed-section tubular thin-shelled structure thats been shown to scale efficiently up to 50m yet maintain its strength. COROTUBs two corrugated thin shells form a closed section, which yields high bending and torsional stiffness, allowing for high dimensional stability. Computational analysis and early tests show that the corrugation provides increased strength against buckling, enabling longer booms and targeting more demanding structural applications than non-corrugated designs. The corrugation geometry that dictates the boom cross-section shape was informed by parametric studies to optimize the parameters that most influence the cross-sections area moment of inertia and torsional constant. The corrugated designs were found to improve the boom bending and axial strength and to shorten the length of the boom transition from flat/rolled to deployed.

Satellites and other spacecraft require maintenance and service after being deployed in orbit, requiring a wide variety of tools that perform multiple maintenance tasks (grip, cut, refuel, etc.). Current drive systems for the tool interfaces on the robotic arms that perform these service tasks are not as robust nor packaged properly for use in the ATDS. The ATDS is one part of a larger in-space servicing system (example shown in the figure below) that must be versatile and perform multiple jobs. Here, innovators at the NASA Goddard Space Flight Center have developed new BLDC motors to provide the torque necessary to drive the wide variety of tools needed for in-space servicing. The four motors provide torque to the coupler drive, linear drive, inner rotary drive, and outer rotary drive of the ATDS. The new BLDC motors will enable the tools attached to the ATDS to be operated in multiple modes of operation. Each of the four motors have been customized with different speed and torque capabilities to meet the different performance requirements of the various actuator drive trains while maintaining a common gearhead across all the motors. Further, the packaging surrounding the motors has been tailored to reduce the overall weight of the motors and reduce the motor footprint to meet the needs of the ATDS. The BLDC motors for the ATDS are available for patent licensing.

Swarms of large numbers of cooperating satellites will introduce new space mission capabilities and complexities. From a mission operations perspective, swarms pose a planning challenge due to the limited scalability of ground operations. The approach of planning and commanding individual satellites simply does not scale for multi-sat swarms of tens or hundreds. If the current state-of-practice continues to be applied, operation of large swarms (e.g., 100 spacecraft or more) will become intractable and cost prohibitive. To avoid this operations bottleneck, a new approach is required: the swarm must operate as a unit, responding to high level commands and constraints. Swarm Orbital Dynamics Advisor (SODA) enables high level user inputs in a single planning cycle. From one high level command, SODA determines all of the required individual satellite maneuvers over time, relieving ground personnel of the tasks of designing and commanding the placement of the swarm members. SODA provides the orbital maneuvers required to achieve a desired type of relative swarm motion. The purpose of SODA is two-fold. First, it encompasses the algorithms and orbital dynamics model to enable the desired relative motion of the swarm satellites. Second, SODA is compatible with a variety of visualization tools. The purpose of SODAs visualization element is to illustrate this concept clearly with a variety of graphics and animations. After computing the optimal orbital maneuvers to modify the swarm, these results are simulated to demonstrate successful swarm control.

NASAs iodine vapor feed system is based on a mechanism that holds and maintains the solid iodine is contact with a heated surface, in this case the walls of the propellant tank. The mechanism provides a robust and reliable steady-state delivery of sublimated iodine vapor to the ion propulsion system by ensuring good thermal contact between the solid iodine and the tank walls. To date, the technology development effort includes extensive thermal, mechanical and flow modelling together with testing of components and subsystems required to feed iodine propellant to a 200-W Hall thruster. The feed system has been designed to use materials that are resistant to the highly-reactive nature of iodine propellant. Dynamic modeling indicates that the feed system tubing can be built is such a way as to reduce vibrationally-induced stresses that occur during launch. Thermal modeling has been performed to demonstrate that the feed system heater power levels are sufficient to heat the tank and propellant lines to operating temperatures, and sublime the iodine in the storage tank to supply propellant for reliable and long-term operation.

This CLAS-ACT is a lightweight, active phased array conformal antenna comprised of a thin multilayer microwave printed circuit board built on a flexible aerogel substrate using new methods of bonding. The aerogel substrate enables the antenna to be fitted onto curved surface. NASA's prototype operates at 11-15 GHz (Ku-band), but the design could be scaled to operate in the Ka-band (26 to 40 GHz). The antenna element design incorporates a dual stacked patch for wide bandwidth to operate on both the uplink and downlink frequencies with a common aperture. These elements are supported by a flexible variant of aerogel that allows the material to be thick in comparison to the wavelength of the signal with little to no additional weight. The conformal antenna offers advantages of better aerodynamics for the airframe, and potentially offers more physical area to either broadcast further distances or to broadcast at a higher data rate. The intended application for this antenna is for UAVs that need more than line of sight communications for command and control but cannot accommodate a large satellite dish. Examples may be UAVs intended for coastal monitoring, power line monitoring, emergency response, and border security where remote flying over large areas may be expected. Smaller UAVs may benefit greatly from the conformal antenna. Another possible application is a UAV mobile platform for Ku-band satellite communication. With the expectation that 5G will utilize microwave frequencies this technology may be of interest to other markets outside of satellite communications. For example, the automotive industry could benefit from a light weight conformal phased array for embedded radar. Also, the CLAS-ACT could be used for vehicle communications or even vehicle to vehicle communications.

The new NASA LaRC Pulsed 2-Micron Laser Transmitter for Coherent 3-D Doppler Wind Lidar Systems is an innovative concept and architecture based on a Tm:Fiber laser end-pumped Ho:YAG laser transmitter. This transmitter meets the requirements for space-based coherent Doppler wind lidar while reducing the mission failure risks. A key advantage of this YAG based transmitter technology includes the fact that the design is based on mature and low-risk space-qualified YAG host crystal. The transmitter operates at a 2096 nm wavelength using Ho:YAG, resulting in high atmospheric transmission (>99%), versus a transmitter operating at 2053 nm using co- doped Tm:Ho:LuLiF, which suffers limited transmission (90%) due to water vapor interference. In-band pumping through Tm:Fiber pump Ho:YAG architecture offers lower quantum defect from 1908 to 2096 nm (9.1%) compared to traditionally used co-doped Tm:Ho:LuLiF of 792 to 2051 nm (61%). The transmitter has an efficient pump compared to LuLF, since YAG has 27% higher pump absorption and 52% lower reabsorption of the emitted 2-micron, resulting in higher efficiency and lower heat load. Being isotropic, YAG is amenable for spatial-hole burning mitigation which supports linear cavity architecture without compromising injection seeding quality. This attribute is important in designing a compact, stable, high seeding efficiency laser. A folded linear cavity for long pulse (>200 ns), transform limited line-width (2.2 MHz) and high beam quality (M2 = 1.04) - the most critical parameters for coherent detection - are easier to achieve using YAG compared to LuLF. Lower heat load results in high repetition rate (>300 Hz) operation, which allows higher probability of wind measurements through broken clouds, off clouds, and below clouds, thus reducing errors and increasing science data product quantity and quality.