Vibration-Dampening Pedestal for MEMS

This thin-film modular pedestal provides passive dampening of undesirable external vibrations that can affect MEMS devices.

Microelectromechanical systems (MEMS) are critical devices for various highly sensitive applications; however, the development and potential fielding of these next-generation smart systems is currently impeded by the inability to satisfy the stringent performance standards for precision and control. These advanced smart systems currently suffer from severe inaccuracies caused by a critical failure of a MEMS inertial measurement unit (IMU), i.e., the angular rate sensor (ARS).

Posted in: Briefs, Mechanical Components

Compact, Portable Device for Structural Vibration Reduction

The device has use in theaters, malls, and other areas where high-traffic floor vibrations can be unsettling to occupants.

Tuned mass dampers are used worldwide to mitigate vibrations in structures like buildings and bridges where excessive movement can be alarming or even sickening to occupants. The vast majority are multi-ton devices that occupy an average of 1,000 square feet, and are complex and costly to install, tune, and maintain.

Posted in: Briefs, Mechanical Components

Origami Techniques Expand Compacted Spacecraft

Origami has once again inspired engineers at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. Besides aesthetic beauty, the Japanese tradition of paper-folding addresses a persistent problem faced by JPL engineers: how do you pack the greatest amount of spacecraft into the smallest volume possible?

Posted in: INSIDER, Aerospace, Joining & Assembly, Motion Control

Webb Telescope Actuators Move with Microscopic Accuracy

The James Webb Space Telescope will be the most powerful space telescope ever built. With a 21-foot diameter, the telescope’s primary mirror is six times larger than the one used by the Hubble Space Telescope. In order for such a large mirror to travel into space, it has to be broken up into multiple segments; in this case, 18 of them. But for the 18 to act as one primary mirror, they have to be adjusted while in orbit.

Posted in: INSIDER, Joining & Assembly, Mechanical Components, Motion Control, Motors & Drives, Positioning Equipment, Optical Components, Optics

Self-Regulating, Freezable Heat Exchanger for Spacecraft

Freeze-tolerant tubing can be used in home and commercial sprinkler systems and water supply lines.

Aspacecraft thermal control system must keep the vehicle, avionics, and atmosphere (if crewed) within a defined temperature range. Water coolant loops are typically used to transport heat to or from the cabin of a crewed spacecraft via heat exchangers to the heat sink systems that reject the heat to space. Water is non-toxic and good for heat transport, but it has a high freeze point. Thus, there is concern that the water loop can freeze and damage the thermal control system unless a low-freeze-point intermediate fluid loop is included. Incorporating a freeze-tolerant water/ice heat exchanger can eliminate this risk, and offers a novel approach to spacecraft thermal control, since parts of the heat exchanger can be selectively frozen to passively increase the turndown of the heat rejection rate. In addition, it has the potential to simplify the thermal control system and thereby reduce its size and mass.

Posted in: Briefs, Mechanical Components, Downsizing, Water, Heat exchangers, Heat exchangers, Spacecraft

Low-Power, Lightweight, Ultra-Compact Reverse Water Gas Shift Reactor

This reactor can be used to produce reagents for methanol, formaldehyde, acetic acid, or ethylene production.

Utilizing CO2 to produce H2O and O2 is critical for sustained manned missions in space, and supports both NASA’s cabin Atmosphere Revitalization System (ARS) and ln-situ Resource Utilization (ISRU) concepts. For long-term missions beyond low Earth orbit where resupply of consumables is significantly more difficult and costly, open-loop ARS can reduce the effectiveness of consumables recovery. The Bosch process has the potential to achieve complete loop closure for 100% O2 recovery; however, it has several limitations, including reactor fouling and low single-pass efficiency. NASA MSFC has been developing an innovative Bosch system comprising a Reverse Water Gas Shift (RWGS) reactor and a downstream Carbon Formation reactor that would significantly improve the overall O2 recovery.

Posted in: Briefs, Mechanical Components, Carbon dioxide, Water, Life support systems, Research and development, Oxygen, Spacecraft

Inflatable Airlock Technologies

This technology can be used for tents, bags, barometric chambers, or wherever environmental barriers are needed.

An airlock used in space can provide the ability to leave a pressurized volume and enter free space. This is necessary to perform maintenance or make repairs to the pressurized volume or visiting spacecraft, construct or repair structures or devices, tend in-space experiments, etc. The airlock is used to provide the transition between internal pressurized volume, i.e. a shirtsleeve environment, and space. Current state-of-the-art units on the Space Station are rigid systems consisting of massive pressure vessels, hatches, and seals. Past efforts have investigated fabric-based ways of forming the airlock pressure volume, but all have used a more traditional metallic or composite door or hatch, which are heavy and difficult to package into a small volume. The need exists for an airlock, pressure vessel, and opening that are lightweight and can be packaged efficiently.

Posted in: Briefs, Mechanical Components, Research and development, Fabrics, Gases, Spacecraft

Carbon Nanotube Purification

This non-invasive method cleans and purifies carbon nanotubes without the use of toxic chemicals.

Development of carbon nanotubes (CNTs), including single-wall and multi-wall nanotubes and nanofibers, into useful devices requires fabrication of CNTs that are relatively free from process residues such as amorphous carbon and metallic particles that are not part of a CNT array grown on a (coated) substrate. Conventional techniques for removal of amorphous carbon and other residues often use one of several techniques. One technique uses post-growth thermal or plasma cleaning of the amorphous carbon with Ox (x=2), which non-selectively attacks the CNT material as well as the amorphous carbon. Metal contaminants are removed using an acid bath, which is again a non-selective process and requires disposal of the strong acids and contaminant removal byproducts. A second technique uses certain toxic gases, such as halogens, to remove the amorphous carbon and other residues. This approach requires disposal of one or more hazardous substances and often requires many hours to complete. A third approach requires holding the amorphous carbon and CNTs in a heated Ox atmosphere for several hours, in order to limit the damage to the CNTs.

Posted in: Briefs, TSP, Mechanical Components

Passive High-Temperature Sealing Device

This device can stop the flow of gas or liquid in conditions of sudden overheating.

Asealing device was developed that acts as a high-temperature shutoff valve for pipes and ducts. The device is an annular ring that can be slipped over the outside of the pipe (or built into a flanged spool piece). The cavity inside the device is filled with a gas, liquid, or even a solid. When exposed to an elevated temperature, the material in the cavity expands, providing sufficient inward force to collapse the thinner process pipe wall, stopping flow within the pipe.

Posted in: Briefs, Mechanical Components, Thermodynamics, Thermodynamics, Seals and gaskets

Tamper-Indicating Bolt

This system detects whether tampering has occurred in a container or compartment during storage or transport.

In storage and/or transport of certain items, the ability to detect tampering with a container or compartment for such items can be necessary and valuable. In the transport of hazardous substances or nuclear materials (including fuels and/or radioactive waste), there are particularly stringent requirements to ensure integrity as well as safe transport and storage of materials. A retailer shipping inventory may need to know whether tampering with the container has occurred during transport to determine if shipment is original and complete.

Posted in: Briefs, Mechanical Components, Logistics, Containers, Packaging, Fasteners, Quality control, Quality control, Safety testing and procedures

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