Motion Control

Propellant Loading Visualization Software

Monitoring of complex propulsion pressure systems has been simplified with colors. Goddard Space Flight Center, Greenbelt, Maryland Complex pressure systems are utilized during testing in the propulsion branch as well as during the propellant loading stage of a mission. Keeping track of the state of such a system becomes more difficult as the complexity of such a system increases, and when extensive procedures are being followed. A book-keeping system is needed for visualizing these complex systems.

Posted in: Briefs, TSP


Energy Efficiency in Machine Tools

Discussions of the efficient use of energy have become more frequent in many sectors of industry. Machine tools comprise numerous motors and auxiliary components whose energy consumption can vary strongly during machining. The main spindle drive, for example, and the coolant system work near their rated power during roughing with a high stock removal rate, while the power consumption during finishing is significantly lower. There is a very close interdependence between the individual components and subassemblies of a machine tool and aspects of productivity and quality. From a detailed examination of manufacturing processes to the power consumption of individual components, potential for savings can be evaluated and measures can be defined for the efficient use of energy.

Posted in: Application Briefs, Articles, Energy Efficiency, Motors & Drives, Machinery & Automation


Robust Gimbal System for Small-Payload Manipulation

This is a low-mass, small-volume gimbal unit. NASA’s Jet Propulsion Laboratory, Pasadena, California Spaceborne gimbal systems are typically bulky with large footprints. Such a gimbal system may consist of a forked elevation stage rotating on top of the azimuth motor, and occupy a large volume. Mounting flexibility of such a system may be limited.

Posted in: Articles, Briefs, TSP, Motors & Drives


A Phase-Changing Pendulum to Control Spherical Robots and Buoy Sensors

The pendulum adds new flexibility to motion control. NASA’s Jet Propulsion Laboratory, Pasadena, California A novel mechanical control system has been proposed for spherical robots to be used as multifunctioning sensor buoys in areas with ambient forces such as winds or currents. The phase-changing pendulum has been specifically designed for Moballs, a self-powered and controllable multifunctioning spherical sensor buoy to be used in the Arctic and Antarctica, or in other solar system planets or moons with atmosphere, such as Mars or Titan. The phase-changing pendulum has been designed to function in different phases: 1) When used as the spherical buoy, the Moball needs to take advantage of external forces such as the wind for its mobility. With no constraints, it could keep the center of mass in the geometric center of the sphere to facilitate the sphere’s movement. 2) However, as soon as the Moball needs to slow down or stop, the sphere’s center of mass can be lowered. 3) Furthermore, the phase-changing pendulum could lean to the sides, thereby changing the direction of the Moball by biasing its center of mass to the corresponding side. The Moballs could take advantage of such a novel phase-changing pendulum to go as fast as possible using the ambient winds, and to stop or steer away when facing hazardous objects or areas (such as the gullies), or when they need to stop in an area of interest in order to perform extensive tests. It is believed that this is the very first time that a pendulum has been suggested to control a spherical structure where both the length and the angle of the pendulum are adjustable in order to control the sphere. 4) Finally, the phase-changing pendulum could also control the sphere in the absence of wind. The spherical sensor buoys or Moballs could use the stored harvested energy (e.g., from sunlight or earlier wind-driven motions) to move the phase-changing pendulum and create torque, and make the spherical sensor buoys initiate rolling with the desired speed and direction. This is especially useful when the spheres need to get close to an object of interest in order to examine it.

Posted in: Articles, Briefs


Computation of Wing Deflection and Slope from Measured Strain

Patent-pending methodology computes detailed wing loads during actual flight. Armstrong Flight Research Center, Edwards, California A lightweight, robust fiber-optic system is the technology behind a new method to compute wing deflection and slope from measured strain of an aircraft. This state-of-the-art sensor system is small, easy to install, and fast, and offers the first-ever means of obtaining real-time strain measurements that can accurately determine wing deflection and slope during flight. Such measurements are particularly useful for real-time virtual displays of wing motion, aircraft structural integrity monitoring, active drag reduction, active flexible motion control, and active loads alleviation.

Posted in: Articles, Briefs, Aviation, Measuring Instruments


Naval Shipyard Automates Dry Dock Operation

Pearl Harbor Naval Station and Hickam Air Force Base have grown up together around the historic port known as Wai’Momi, adjacent to Honolulu. Pearl Harbor Naval Shipyard (PHNSY), located at Joint Base Pearl Harbor-Hickam, is a one-stop regional maintenance center for the Navy’s surface ships and submarines. It is the only intermediate maintenance facility for submarines in the Middle Pacific.

Posted in: Application Briefs


Integrated Motion Solution Keeps Laser Marking Machine Costs Down

As the demands of traceability and compliance are put on manufacturers, using a laser provides permanent marking of a variety of information, including 2D bar codes, serial numbers, company information, and logos.

Posted in: Applications, Application Briefs