Motion Control/​Automation

Explore the latest developments in motion control and automation. Discover innovative advances from NASA and major research labs in robotics, autonomous vehicles, industrial automation, PID controller applications, motor drives and power transmissions.

Briefs : Motion Control
Manually Operated Weld-Filler-Wire Feeder

A simple, manually operated mechanical device will ensure a smooth and predictable motion when feeding filler wire into a molten weld pool in gas tungsten arc welding (GTAW). This device simplifies and/or reduces the requirements for a dexterous hand to hold and manipulate filler wire. This device will...

Briefs : Motion Control
Asymmetric Dual-Axis Goniometer for Positioning on a Sphere

The ability to position an object at various locations corresponding to a portion of a spherical surface has long been accomplished using nested goniometers, in which, as observed from above, the apparent motion is readily described in a Cartesian ("XY") frame. In certain applications,...

Briefs : Motion Control
Multiple-DOF Surface-Acoustic-Wave Piezoelectric Motors

Surface-acoustic-wave (SAW) piezoelectric motors capable of operating in multiple degrees of freedom (DOFs) simultaneously have been proposed. A particularly useful motor of this type could provide both linear and rotary motions. Another particularly useful motor of this type would feature...

Briefs : Motion Control
Electrohydrodynamic Pumping Enhances Operation of Heat Pipe

Experiments have shown that electrohydrodynamic pumping can be utilized to increase the heat-transport capacity of a heat pipe. More specifically, electrohydrodynamic pumping can be used to increase the flow of liquid to the evaporator section of the heat pipe; the increased flow helps...

Briefs : Motion Control
Rolling-Piston Compressor With Flow-Through Lubrication

The figure presents a simplified and partly schematic view of a two-stage rolling-piston compressor that is undergoing development for use as the prime mover in a vapor-compression heat pump. In comparison with equally rated compressors used heretofore in vapor-compression heat pumps, this...

Briefs : Motion Control
Closed/Momentary-Opening/Closed Solenoid Valve

A proposed solenoid-actuated valve would open for a short time to pass a very small quantity of fluid. The valve could be used to meter a specified total quantity of the fluid through repeated actuations.

Briefs : Motion Control
Formulation and Algorithm for Multi-Flexible-Body Dynamics

An improved formulation of the dynamics of multiple flexible bodies coupled via joints, and an algorithm that implements the formulation, have been developed at Johnson Space Center (JSC). A robot arm with multiple, somewhat flexible links is a prime example of a dynamic system to which...

Briefs : Motion Control
Myoelectric Teleoperation for Robotics and Prosthetics

Johnson Space Center is sponsoring continuing research on the use of myoelectric signals to control dexterous robotic and prosthetic hands. This research is expected to advance the state of the art beyond that of today's most common, commercially available, myoelectrically controlled...

Briefs : Motion Control
Efficient Periodic Driving of Piezoelectric Benders

Modified Hartley oscillator circuits are being developed for use in driving large piezoelectric benders in periodic motion, as in some piezoelectrically driven pumps. These circuits decrease the time-averaged consumption of power and thus increase energy efficiency by recycling large fractions...

Briefs : Motion Control
Non-Inertial Calibration of Vibratory Gyroscopes

A proposed method of calibration of micromachined vibratory gyroscopes would make it unnecessary to test the gyroscopes at known rates of rotation. At present, calibration entails inertial tests in which the gyroscopes are exposed to tumble and rotation maneuvers on multiaxis precise rotation...

Briefs : Motion Control
Acoustic-Emission-Analysis System for Diagnosis of Machinery

A personal-computer-based system has been developed as a prototype of electronic signal-processing and computing systems for diagnosis of turbines, motors, and other rotary machines through analysis of acoustic emissions. The system includes acoustic sensors that respond in the...

Briefs : Motion Control
Motion-Measuring Circuit for a Vibratory Capacitive Sensor

The figure illustrates an improved electronic circuit that generates a signal proportional to either the instantaneous vibrational velocity or the instantaneous position (equivalently, the instantaneous vibrational displacement) of a vibratory capacitive sensor of the type discussed in...

Briefs : Motion Control
Pulse-Mode Reaction Control System Thruster

A spacecraft reaction-control-system (RCS) thruster now undergoing development generates a thrust of 870 lbf (3,870 N) by burning ethanol and liquid oxygen (LOX), which are nontoxic. The performance of the thruster has been tested in operation in multiple pulse modes with pulses as short as 160 ms;...

Briefs : Motion Control
Vibration-Regulating Circuit for a Mechanical Resonator

The figure illustrates an improved electronic circuit that excites constant-magnitude vibrations in an electrostatically actuated, capacitively sensed mechanical resonator. The circuit can be adapted, for example, to a planar vibratory microgyroscope like the one described in the preceding...

Briefs : Motion Control
Using Commercial-Grade Tb/Dy in Magnetostrictive Actuators

Single crystals of Tb-Dy alloys exhibit magnetostrictive strains approaching 1 percent and can generate forces sufficiently large to make them useful as actuators in cryogenic mechanical devices. These actuators offer many advantages over piezoelectric actuators and actuators using...

Briefs : Motion Control
Circuit Generates Rotation Signal From a Vibratory Gyroscope

This is the first of four articles that address various issues concerning the generation and utilization of electronic signals in the operation of micromachined planar vibratory microgyroscopes and other sensory devices that include electrostatically actuated, capacitively sensed...

Briefs : Motion Control
Q-Compensation Circuit for a Planar Vibratory Microgyroscope

Electronic circuitry has been devised to compensate for variations in the resonance quality factor (Q) of a planar vibratory microgyroscope like that described in the first of the two preceding articles. That is, the circuit makes the scale factor of the gyroscope (the factor of...

Briefs : Motion Control
Controller for Bistable Brakes

The circuit shown in the figure is a controller for bistable brakes. The use of bistable brakes reduces energy consumption and spurious heating, as explained below.

A bistable brake is one that can stay in the "on" or "off" position without consuming energy from an outside source. To switch a bistable brake...

Briefs : Motion Control
Neural Networks Monitor the Health of Space Shuttle Valve

The gaseous hydrogen flow control vale (GH2FCV; see Figure 1) is a critical space shuttle component that controls the pressure of the hydrogen external tank during launch and ascent to orbit. The valve is one of the components that are to be monitored by the Integrated Vehicle Health...

Briefs : Motion Control
Radio-Frequency Wireless Flight-Control System

Technological advances have driven the evolution of aircraft flight-control systems. In the dawn of 20th-century aviation, the Wright Brothers used cables and warping of wing surfaces to change the shapes of flight-control surfaces. As engineers designed aircraft capable of flying faster, higher,...

Briefs : Robotics, Automation & Control
Adaptive Variable Bias Control for Magnetic Bearings

Adaptive variable bias control (AVBC) is an improved technique for controlling the currents supplied to the electromagnets in magnetic bearings. In AVBC, the bias currents are varied in such a way as to reduce overall power consumption.

Briefs : Motion Control
MEMICA: a Concept for Reflecting Remote-Manipulator Forces

The term "mechanical mirroring using controlled stiffness and actuators" ("MEMICA") denotes a developmental concept for reflecting contact forces, displacements, mechanical damping, and temperature from the hand of a remote robotic manipulator back to the hand of a human operator who...

Briefs : Motion Control
Mass-Produced Hollow Cathodes Will Cost Less

A commercial version of the NASA plasma-contactor hollow-cathode assembly (PC HCA) has been developed. The NASA PC HCA is a highly reliable hollow discharge cathode that is the most thoroughly understood, tested, and mature of all hollow cathodes that have been considered for use in electric...

Briefs : Motion Control
Axial Force as Indication of Alignment of Threaded Fasteners

A developmental technique for automated alignment of threaded fasteners involves the use of the axial force between the fasteners as an indication of alignment. The technique was conceived as a means to guide a robot that is required, for example, to join a bolt with a nut.

Briefs : Motion Control
Small-Stroke, High-Frequency Reciprocating Pump

A proposed reciprocating pump would operate at a small stroke and would contain no sliding parts. The oscillatory motion of a piston in the pump could be provided by a magnetostrictive actuator, for example.

Briefs : Motion Control
Heat-Driven Pulse Pump

The heat-driven pulse pump has been invented in an effort to satisfy a need for pumps that can circulate heat-transfer fluids at low flow rates with high reliability over long operational lifetimes. The heat-driven pulse pump (HDPP) is so named because it generates pumping action by exploiting periodic (pulsed) heating...

Briefs : Motion Control
Improved Magnetostrictive Pump

An improved magnetostrictively actuated pump has been developed to satisfy a need for a small, low-pressure, high-flow-rate fluid pump that contains few moving parts and can run reliably for long periods without maintenance. The pump could be used, for example, to circulate water in the portable life-support...

Briefs : Robotics, Automation & Control
Alternative One-Time-Opening Miniature Isolation Valve

The figure depicts a proposed miniature, electrically actuated, one-time-opening isolation valve that would be made mostly of silicon, by use of micromachining techniques. Isolation valves are needed in systems in which fluids must be stored for long times until use, with no leakage or...

Briefs : Robotics, Automation & Control
Insectile and Vermiform Exploratory Robots

A six-legged robot resembling an insect and a legless segmented robot resembling a worm (see figure) have been proposed as prototypes of biomorphic explorers  small, mobile, exploratory robots that would be equipped with microsensors and would feature animallike adaptability and mobility. Biomorphic...

Briefs : Robotics, Automation & Control
Better Densification of Cryogenic Liquid Rocket Propellants

An improved system for densifying (by cooling) the liquid hydrogen and liquid oxygen used as propellants for the space shuttle has been proposed. These propellant liquids are cooled to minimize the sizes of tanks needed to store them and to reduce maximum operating pressures. The...