Mechanical & Fluid Systems

Access our comprehensive library of technical briefs on mechanical and fluid systems, from engineering experts at NASA and government, university, and commercial laboratories.

Briefs: Mechanical & Fluid Systems

Equations have been derived to fill a gap in previously published standard collections of stress-and-strain formulas: These are equations for deflection of a thin circular membrane...

Briefs: Mechanical & Fluid Systems
Briefs: Mechanical & Fluid Systems

Improved pressure probes have been designed to give nearly instantaneous readings of the time-varying local static pressure in flowing gases. The probes have been installed in a wind tunnel...

Briefs: Mechanical & Fluid Systems

A generic actuator has been designed to amplify the piezoelectric effect. The Bidirectional Operating Actuator (BOA) amplifies the stroke of a piezoelectric element and reorients it through a kinematic...

Briefs: Mechanical & Fluid Systems

Engineers have designed a new device, called the Smart Washer, that can electromagnetically detect bolthole cracks in metal structures. The device is a metal washer that contains...

Briefs: Mechanical & Fluid Systems

A structure provides rigid support for a cryogenic component but transmits minimal heat. The structure includes two beams of Invar (or equivalent low-thermal expansion iron/nickel alloy) that...

Briefs: Mechanical & Fluid Systems
Multichannel Ultrasonic-Bolt-Tension-Gauge System

An improved system for measuring tensions in multiple bolts is based on the usual measurement of the times of propagation of ultrasonic waves along the bolts, but the quantities measured and the method of processing the measurement data differ from those of conventional ultrasonic bolt-tension...

Briefs: Mechanical & Fluid Systems
Automated Calibration of Torque Analyzers Without Weights

An automated apparatus calibrates digital torque analyzers that, in turn, are used to verify the accuracies of torque wrenches. The apparatus is located in a central laboratory, and the digital torque analyzers are brought to the laboratory for calibration. Previously, the torque...

Briefs: Mechanical & Fluid Systems
Flexible Actuators for Small, Mobile, Special-Purpose Robots

A report discusses flexible microactuators for a proposed generation of small, mobile, special-purpose robots. Aspects of this topic were discussed in two previous articles in NASA Tech Briefs: "Thin-Film, Light-Energized Bimorph Micromechanical Actuators" (NPO-19607), Vol. 20, No. 8...

Briefs: Mechanical & Fluid Systems

The figure presents a simplified view of a shaft seal that provides a small flow of neutral buffer gas to prevent contact between different gases contained in two adjacent regions along the shaft. In the original application,...

Briefs: Mechanical & Fluid Systems

The figure illustrates one of several related pin-puller mechanisms that harness the recovery characteristics of a shape-memory alloy (SMA). Like some other SMA-actuated mechanisms...

Briefs: Mechanical & Fluid Systems
Wheel Drive of Mars Rover

A brief report summarizes the design of the lightweight, high-torque wheel drive of a small robotic vehicle used to explore the surface of Mars. Planetary gearing was selected for compactness and high torque capability. The input stages were fitted with ball bearings to survive the cold (down to -100 °C) Martian...

Briefs: Mechanical & Fluid Systems

Rigid, guyed masts of a proposed type for supporting meteorological instruments would be designed to withstand considerably stronger winds than those conventionally used. The proposed fairings...

Briefs: Mechanical & Fluid Systems

A self-contained impact-type damper for a bellows-type face seals suppresses dynamic instability or chatter. In current practice, damping in a typical seal is accomplished through...

Briefs: Mechanical & Fluid Systems

Permanent-magnet rotary bearings with ferrofluid stabilization in the axial degree of freedom are undergoing development. These bearings are totally passive, yet stable in all degrees...

Briefs: Mechanical & Fluid Systems

A Stirling cooler is a mechanical system that approximates the ideal gas cycle. Often associated with airborne or portable cooling applications that require compact design and low input power,...

Briefs: Mechanical & Fluid Systems

There has been some success in continuing efforts to increase the service lifetimes of the guide rolls in hot-roll-slitter machines in the steel industry. In these machines, hardened knives are...

Briefs: Mechanical & Fluid Systems

Weightless Environment Training Facility Inertial Training Spheres (WETFITSs) are proposed neutrally buoyant training tools that would be used in NASA's Weightless Environment...

Briefs: Mechanical & Fluid Systems
Applying Controlled Pressure Distributions to Complex Curved Surfaces

A technique for applying controlled test pressures to curved surfaces is based on a principle similar to that of a compartmented pilot's or astronaut's pressure suit. The technique involves the use of airbags that accommodate geometric complexity in both the surface under...

Briefs: Mechanical & Fluid Systems
Equations for Failure Modes of Mechanical Systems

A report presents information compiled from a search of the literature on failure modes of mechanical systems. The report was written to provide a reference base for the application of first-order reliability methods to mechanical systems in the development of a system-level design methodology....

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