Mechanical & Fluid Systems

Fundamentals of Wire, Cable, and Connectivity

Continuous supply of electric power or faultless data transfer, provided mostly through wiring, are primary requirements affecting virtually all systems. This results in stringent requirements for production, installation, and operation of cables.

Posted in: White Papers, Mechanical Components, Motion Control, Automation, Robotics


LAPP PLAYBOOK — Next Generation Cables For Factory Automation

Achieving maximum productivity and minimizing downtime are critical in production line equipment or any automation applications.

Posted in: White Papers, Aerospace, Defense, Mechanical Components, Mechanics, Motion Control


Development of the Orion Crew-Service Module Umbilical Retention and Release Mechanism

The design is highly modular, and can easily be adapted to other vehicles/modules and alternate commodity sets.The Orion Crew-Service Module (CM/SM) umbilical retention and release mechanism supports, protects, and disconnects all of the cross-module commodities between the spacecraft's crew and service modules. These commodities include explosive transfer lines, wiring for power and data, and flexible hoses for ground purge and life support systems. Initial development testing of the mechanism's separation interface resulted in binding failures due to connector misalignments. Separation of the umbilical lines between the Crew Module (CM) and the Service Module (SM) happens as part of the vehicle separation activities prior to reentry. If the umbilical fails to separate successfully, the crew and spacecraft will likely be lost.

Posted in: Briefs, Mechanical Components, Mechanics, Architecture, Fasteners, Entry, descent, and landing, Spacecraft


Micro-Lid for Sealing a Sample Reservoir for Micro-Extraction Systems

Improved micro-extraction systems could be useful for military remote sensing using microfluidics.Great strides are taken to miniaturize spaceflight instrumentation, particularly analytical systems such as liquid chromatographs, gas chromatographs, and mass spectrometers. With miniaturization of instruments, large amounts of samples are no longer required. Therefore, a lesser quantity of sample from the environment needs to be acquired and extracted. Current practices of sample extraction are large in volume and consume an enormous amount of power, which is inconsistent for microfluidic instruments in development. These consume minute amounts of power and are of low mass. There have been efforts to create micro-sample extraction systems; however, a downfall of those systems is the inability to automatically close sample reservoirs.

Posted in: Briefs, Mechanical Components, Mechanics, Containers, Seals and gaskets, Test equipment and instrumentation, Spacecraft


Single-Fluid-Pumped Radiators with Increased Turn-Down Ratio and Control in the Stagnation Regime

The system trades mass-optimized heat rejection for a human-rated, single-fluid pumped system of greater heat rejection range and passive control.Fluid-pumped radiators are used to reject heat from structures to space. A fluid travels inside the structure to collect heat, and then travels external to the structure through radiators where the heat is rejected to space via radiation heat transfer. A radiator is essentially several tubes attached to a thermally conducting plate or face sheet. The fluid cools as it travels along the inside of the tubes, and then returns to the inside of the structure to repeat the heat rejection cycle. If the structure contains humans, the fluid in the structure must be nontoxic and nonflammable. Further, as space can be extremely cold (4 K), the fluid external to the structure may freeze, particularly during low-power operations where heat rejection needs are minimal. Freezing of the fluid renders the radiator inoperable, and unfreezing a radiator can be very difficult, power-intensive (i.e. heaters), and/or timely. For these reasons, two fluids may be used: one inside that is compatible with humans (e.g. water), and one outside that has a low freezing point (e.g. ammonia). The heat is then transferred from the inner loop to the external loop through a heat exchanger. This dual-loop system is more complex and heavier than a single-loop system. However, as the outer loop does not freeze as easily, the dual-loop radiator system can be operated at lower heat rejection loads, increasing its overall heat rejection range (or turn-down ratio) over that of the single-loop system.

Posted in: Briefs, Mechanical Components, Mechanics, Heat exchangers, Heat transfer, Radiators


Designing for Mechanical and Signal Integrity in Handheld Medical Treatment Applications

Handheld medical devices must perform across a wide range of device specifications and end-user environmental conditions. Mechanical and signal integrity of cable components is especially important for high-level performance, accuracy, durability, longevity, and user satisfaction. A great variety of insulating and jacketing material options exist for wire and cable in medical electronics. Performance factors that affect material selection decisions include biocompatibility, disinfection and sterilization compatibility, revision control assurance, environmental regulatory compliance, aesthetics, flexibility, durability, and cost. Subtle differences in priority may result in significant differences in product design, as well as overall cost.

Posted in: White Papers, White Papers, Manufacturing & Prototyping, Mechanical Components, Bio-Medical, Medical


Metal Stamping Design Guidelines

Metal Stamping provides an economical way to produce quantities of parts that can possess many qualities, including strength, durability, wear resistance, good conductive properties, and stability. In this paper, we are sharing some ideas that can help you design a part that optimizes all the features that the metal stamping process offers.

Posted in: Briefs, TSP, Aeronautics, Manufacturing & Prototyping, Materials, Mechanical Components, Design processes, Stamping, Metals, Parts


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