Johns Hopkins University

Leo R Gauthier, Jr

James E McDonald

Leroy Brunner

David G Drewry, Jr

John M Klimek

Angela L Wesner-Barrios

Louis A Mattes

Kim Randal Fowler

David M VanWie

Christopher L Eddins

Kenneth W Harclerode

Harlan Ray, Iii

Bruce A Land, Iii

Provided herein are a system and a method thereof which allows for calibrating a laser or getting characteristics of the laser by measuring the temporally and spatially resolved beam profile and power density cross-section using non-contact radiometry. An example method includes receiving a radiation beam from a light source by protrusions that protrude from a plate. The example method further includes imaging the protrusions, measuring a respective temperature of each of the protrusions based on the imaging, and profiling the radiation beam based on the measuring.

High power laser profiler

An example method for determining a mobile device position and orientation is provided. The method may include capturing a two-dimensional image of a surface including at least four markers, and determining a unit direction vector for each of the at least four markers based on an association between a pixel location of each of the at least four markers in the two-dimensional image. The method may further include determining apex angles between each pair of the unit direction vectors, and determining marker distances from the imaging sensor to each of the at least four markers via a first iterative process based on the apex angles. Additionally, the method may include determining the mobile device position with respect to the coordinate frame via a second iterative process based on the marker distances, the apex angles, and the coordinates of each of the at least four markers.

Imaging sensor-based position detection

A serial digital data acquisition receiver (SDDAR) or system of receivers may include an opto-isolator assembly, sampling logic and a USB interface. Both a CLK signal and a DATA signal may each pass through the opto-isolator assembly upon receipt of the CLK and DATA signals at the SDDAR or system. The sampling logic may be operably coupled to the opto-isolator assembly and be configured to determine a point at which to sample the DATA signal based on state changes in the CLK signal. The USB interface may be operably coupled to the sampling logic and an output terminal. The USB interface may be configured to provide telemetry data for processing, display or recording at the output terminal, and may be configured to enable the SDDAR or system to be powered from the output terminal.

Dual autonomous telemetry data acquisition system and real time opto-isolated receivers for use therewith

A system for detecting and tracking one or more of direction, orientation and position of one or more light sources includes one or more optical fiber sensors configured to receive light from the one or more light sources and to generate a plurality of cones of light according to relative positions of the one or more optical fiber sensors relative to the one or more light sources. The system includes light data processing circuitry configured to detect characteristics of the plurality of cones of light and to determine one or more of direction, orientation, or position of the one or more light sources relative to the one or more optical fibers.

Non-contact fiber optic localization and tracking system

Disclosed is a method of forming an optical monitoring or transmitting light guide and a resulting apparatus that begins by bonding a bundle of optical fibers together using an epoxy and polishing the distal end of the bundle of optical fibers to create an optical aperture. The ratio of fiber size to binder particulate size of the epoxy used in the bonding process is sufficient to maintain the integrity of the bundle of optical fibers during the polishing of the distal end. The method positions the bundle of optical fibers into a protective sheath and a connector. The coefficient of thermal expansion of the epoxy used in the bonding process matches that of the connector. Once assembled, the invention positions the connector through the opening in the surface of a device, such that the distal end of the bundle of optical fibers is either recessed in, substantially flush with, or extends from the surface of the device through which the connector extends, depending on field-of-view requirements.

High temperature light guide

The present invention is directed to a hitpoint sensor for a surface of interest, the hitpoint sensor having an optical fiber which is wound around or otherwise covering the surface, and a data processor connected to the ends of the optical fiber. When a collision with the surface occurs, light is generated which passes through the optical fiber. The ends of the fiber are connected to the data processor which uses arrival time information of the light signals arriving at the processor to determine the impact location on the surface. There are several modes in which the processor can operate to make this calculation.

Light-speed hitpoint sensor

Sensing elements that quickly and accurately determine if a liquid or gas is present around the sensing elements are disclosed. These sensing elements find particular application in identifying the location of the cavity wall in which a supercavitating vehicle is operating, relative to the vehicle. In certain embodiments signal emitting elements carried on the vehicle emit signals towards the presumed position of the cavity wall, and sensing elements carried on the vehicle receive the emitted signals after they are reflected off of the cavity wall. The sensing elements identify the location where the reflected signal is received, and based on this identified location, the location of the cavity wall is determined. In alternative embodiments, sensing elements are positioned along fins extending outward with respect to the hull of the vehicle, and the sensors sense the presence of liquid or gas.

Sensor elements for supercavitating vehicles

A method of determining the path of a projectile comprises detecting multiple time of arrivals of the projectile in multiple intersecting planes and determining the path and speed of the projectile based on the multiple times of arrivals.

Method for detecting projectile impact location and velocity vector

An optical sensor and method for detecting a projectile velocity vector includes optically detecting the arrival of a projectile. The sensor includes a sandwich of a transparent layer within two reflective layers, which in turn are within two opaque layers. An optical sensor structure includes a set of sensors positioned in respective planes, wherein at least two non-parallel optical sensors are used for each trajectory dimension of interest that differs from the primary direction of motion of the projectile and one additional optical sensor may be used for independent measurement of velocity attenuation. An optical sensor structure includes a set of sensors positioned in respective planes, wherein at least two of the optical sensors are oriented in respective planes that are parallel and potentially offset from each other. A tiling of the optical sensors or optical structures is also possible.

Optical sensor and method for detecting projectile impact location and velocity vector

A plurality of energy couplers () receives signals from an energy pulse, each of the energy couplers () having a defined field of view, the field of views of at least some of the energy couplers being overlapping. A transducer () converts the signals received from the energy pulse to voltage or current output signals that are then amplified. A threshold circuit () triggers when the amplitude of a signal caused by the energy pulse exceeds a predetermined level, and signal processing instrumentation () then calculates the source location and/or the intensity and/or the initiation time of the energy pulse based on the timing of the output signals associated with individual energy couplers ().

Apparatus and method for detecting the location, intensity and initiation time of an energy pulse

A damping gyrometer comprised of at least two and preferably four rotating paddles attached to a common central elevated low-friction pivot point via rising radial arms. A stand with a concave glass element provides a low-friction support as a pivot point seat for the pivot point. All elements of the apparatus are non-conductive. Once set into motion, the only force acting on the gyrometer are the pivot point friction and the damping effects of the medium in which it spins. A laser beam and photodetector (or alternatively a laser displacement sensor), along with customized software algorithms are used to measure the rotational rate and, hence, the deceleration rate of the apparatus which can then be used to determine properties of the medium in which it spins, including changes in density, pressure, and temperature. The measurement can also be directly related to the electron density in the case of weakly ionized gases.

Damped paddle wheel for plasma chamber shock tube

An ionization chamber that detects changes in temperature of electrical insulation with a corresponding change in voltage. This voltage change can be relayed through an operational amplifier and a comparator to a device receiving the signal, thus triggering the necessary alarm and preventing fires caused by electrical arcing.

Growing community of inventors

Ellicott City, MD, United States of America

Leo R Gauthier, Jr