Motion Control

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


Three-Phase Power Conversion in a Single Step

Marotta Controls is revolutionizing power conversion with 1-STEP, a patent-pending circuit solution that uniquely achieves three-phase active power factor correction, power regulation and electrical isolation in a single conversion step.

Posted in: White Papers, Defense, Electronics & Computers, Motion Control


Evaluation Standard for Robotic Research

Universal benchmarks can standardize the measurement of robotic manipulation tasks.The Yale-CMU-Berkeley (YCB) Object and Model Set provides universal benchmarks for labs specializing in robotic manipulation and prosthetics. About two years ago, Aaron Dollar, an associate professor of mechanical engineering and materials science at Yale University, came up with the benchmark idea to bring a level of specificity and universality to manipulation tasks in robotics research. He enlisted the help of two former colleagues in the robotics community, Dr. Siddhartha Srinivasa from Carnegie-Mellon University and Dr. Pieter Abbeel of the University of California, Berkeley.

Posted in: Briefs, Motion Control, Automation, Kinematics, Research and development, Robotics, Quality standards, Biomechanics


How To Substantially Reduce Encoder Cost While Gaining Functionality With Multi-Turn Rotary Position Sensors

Many applications require rotation counters that can measure angles greater than 360º. However the low-cost 10-turn potentiometers most design engineers are familiar with can’t always meet user requirements for resolution and reliability. As an alternative, optical absolute encoders are too expensive for many applications. These solutions require a continuous power supply or they will lose count when power is restored. Also, geared technology/rotation counters are subject to significant wear.

Posted in: White Papers, Motion Control, Automation, Robotics, Data Acquisition, Sensors


Mechanisms for Achieving Non-Sinusoidal Waveforms on Stirling Engines

The current state-of-the-art Stirling engines use sinusoidal piston and displacer motion to drive the thermodynamic cycle and produce power. Research performed at NASA Glenn has shown that non-sinusoidal waveforms have the potential to increase Stirling engine power density, and could possibly be used to tailor engine performance to the needs of a specific application. However, the state-of-the-art Stirling engine design uses gas springs or planar springs that are very nearly linear, resulting in a system that resonates at a single frequency. This means that imposing non-sinusoidal waveforms, consisting of multiple frequencies, requires large forces from the drive mechanism (either the alternator or the crank shaft). These large forces increase losses, and increase the size and requirements of the control system. This innovation aims to reduce the external forcing requirements by introducing internal mechanical components that provide the forces necessary to achieve the desired waveforms.

Posted in: Briefs, Mechanical Components, Mechanics, Motion Control, Alternators, Crankshafts, Engine efficiency, Stirling engines


Improving Stirling Engine Performance Through Optimized Piston and Displacer Motion

Stirling engines typically achieve high efficiency, but lack power density. Low power density prevents them from being used in many applications where internal combustion engines are viable competitors, and increases system costs in applications that require Stirling engines. This limits their operating envelope in both terrestrial and space applications. Sinusoidal piston and displacer motion is one of the causes of low power density. Previous work proposed solving this problem by replacing sinusoidal waveforms with waveforms that more closely approximate those of the ideal Stirling cycle. However, when working with real engines, imposing ideal waveforms has been shown to reduce power density and efficiency due to increased pressure drop through the regenerator and heat exchangers.

Posted in: Briefs, Fluid Handling, Mechanical Components, Mechanics, Motors & Drives, Engine efficiency, Pistons, Stirling engines


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