Abstract: An automatic gain control (AGC) system includes at least one variable-gain component having a controllable gain over a gain control range and a sensor for sensing an amplitude of a signal from the at least one variable-gain control component. The sensor may have an operating window based upon the signal that is smaller than the gain control range of the at least one variable-gain component. The AGC system may also include a controller responsive to the sensor for controlling the at least one variable-gain component according to coarse and fine gain values to set the amplitude of the signal within the operating window of the sensor. The controller may implement at least one coarse gain jump from a current coarse gain value to a new coarse gain value when the sensor indicates the amplitude is outside the operating window. The controller may further implement movement to a fine gain value when the sensor indicates the amplitude is in the operating window.

Abstract: A dual cantilevered electromagnet-based gripping mechanism has a reduced number of parts and operates with low power demand properties for use in micro-tool applications. Juxtaposed, cantilever-supported electromagnets, to which object engagement elements, such as gripping pincers, are attached, have their cores made of a low permeability material, such as stainless steel, that does not retain an induced magnetic field once the energizing current is terminated. By controlling the energizing current through the coils of the electromagnets, the magnitude of mutual magnetic attraction against the spring forces of their supporting cantilever arms is defined. This allows mutual separation between the electromagnets and object engagement force to be controlled, for seizure, retention, and release of an object. The displacement vs.

Abstract: An automatic gain control (AGC) system includes at least one variable-gain component having a controllable gain over a gain control range and a sensor for sensing an amplitude of a signal from the at least one variable-gain control component. The sensor may have an operating window based upon the signal that is smaller than the gain control range of the at least one variable-gain component. The AGC system may also include a controller responsive to the sensor for controlling the at least one variable-gain component according to coarse and fine gain values to set the amplitude of the signal within the operating window of the sensor. The controller may implement at least one coarse gain jump from a current coarse gain value to a new coarse gain value when the sensor indicates the amplitude is outside the operating window. The controller may further implement movement to a fine gain value when the sensor indicates the amplitude is in the operating window.

Abstract: An antenna positioner includes a housing and a hub mounted within the housing. A substantially planar configured support plate is rotatably mounted on the hub. A substantially elongate antenna is pivotally mounted on the support plate. An elevation drive mechanism is mounted on the support plate and interconnects the antenna for pivoting the antenna a predetermined angle and adjusting elevation of the antenna. An azimuth drive mechanism is mounted on the support plate and interconnects the hub and rotates the support plate relative to the hub a predetermined arcuate distance relative to the hub and adjusts azimuth of the antenna. A controller is operatively connected to the elevation drive mechanism and the azimuth drive mechanism and controls the azimuth and elevation drive mechanisms to adjust elevation and azimuth.

Abstract: An antenna positioner control system and related method is disclosed. The antenna positioner control system includes a housing and a hub mounted within a housing. A support plate is rotatably mounted on the hub. An antenna is pivotally mounted on the support plate. At least one elevation drive servomotor is mounted on the support plate and interconnects the antenna for pivoting the antenna a predetermined angle and adjusting elevation of the antenna. At least one azimuth drive servomotor is mounted on the support plate and interconnects the antenna for rotating the support plate relative to the hub a predetermined arcuate distance for adjusting azimuth of the antenna. An antenna control unit is operatively connected to the elevation drive servomotor and azimuth drive servomotor and includes an elevation control circuit and azimuth control circuit.

Abstract: Apparatus for sampling a material in a container both in a laboratory environment and in a field environment is shown. The apparatus includes a portable pump for generating either a partial pressure with respect to atmosphere or a partial vacuum with respect to atmosphere. The partial vacuum is used to force the material from the container through a collection tube into a specimen bottle. When the material in the container is too viscous to be directly drawn into the specimen bottle, a pressure is applied to one end of the collection tube and the material in the collection tube is driven into the specimen bottle. The footpump is modified to provide both a pressure and a vacuum nozzle and is easily portable to a remote location site.

Abstract: An electromagnetic detection apparatus for sensing an object, has a transter for radiating electromagnetic energy toward the object. The apparatus also has an array of at least three spaced receiving antennas and one parasitic antenna. The parasitic antenna is spaced from and mounted alongside the array. Also included is a phase detection circuit for measuring the phase difference between signals received by one of the receiving antennas with respect to the other two. This apparatus can sense phase difference and correlate it to the azimuthal position of the object.