ORCA Prototype Ready to Observe Ocean

If selected for a NASA flight mission, the Ocean Radiometer for Carbon Assessment (ORCA) instrument will study microscopic phytoplankton, the tiny green plants that float in the upper layer of the ocean and make up the base of the marine food chain.Conceived in 2001 as the next technological step forward in observing ocean color, the ORCA-development team used funding from Goddard’s Internal Research and Development program and NASA’s Instrument Incubator Program (IIP) to develop a prototype. Completed in 2014, ORCA now is a contender as the primary instrument on an upcoming Earth science mission.The ORCA prototype has a scanning telescope designed to sweep across 2,000 kilometers (1,243 miles) of ocean at a time. The technology collects light reflected from the sea surface that then passes through a series of mirrors, optical filters, gratings, and lenses. The components direct the light onto an array of detectors that cover the full range of wavelengths.Instead of observing a handful of discrete bands at specific wavelengths reflected off the ocean, ORCA measures a range of bands, from 350 nanometers to 900 nanometers at five-nanometer resolution. The sensor will see the entire rainbow, including the color gradations of green that fade into blue. In addition to the hyperspectral bands, the instrument has three short-wave infrared bands that measure specific wavelengths between 1200 and 2200 nanometers for atmospheric applications.The NASA researchers will use ORCA to obtain more accurate measurements of chlorophyll concentrations, the size of a phytoplankton bloom, and how much carbon it holds. Detecting chlorophyll in various wavelengths also will allow the team to distinguish between types of phytoplankton. Suspended sediments in coastal regions could also be detected by the instrument.SourceAlso: Learn about a Ultra-Low-Maintenance Portable Ocean Power Station.

Posted in: News, Optics, Photonics, Sensors, Measuring Instruments


New Navigation Software Cuts Self-Driving Car Costs

A new software system developed at the University of Michigan uses video game technology to help solve one of the most daunting hurdles facing self-driving and automated cars: the high cost of the laser scanners they use to determine their location.Ryan Wolcott, a U-M doctoral candidate in computer science and engineering, estimates that the new concept could shave thousands of dollars from the cost of these vehicles. The technology enables them to navigate using a single video camera, delivering the same level of accuracy as laser scanners at a fraction of the cost."The laser scanners used by most self-driving cars in development today cost tens of thousands of dollars, and I thought there must be a cheaper sensor that could do the same job," he said. "Cameras only cost a few dollars each and they're already in a lot of cars. So they were an obvious choice."Wolcott's system builds on the navigation systems used in other self-driving cars that are currently in development, including Google's vehicle. The navigation systems use three-dimensional laser scanning technology to create a real-time map of their environment, then compare that real-time map to a pre-drawn map stored in the system. By making thousands of comparisons per second, they are able to determine the vehicle's location within a few centimeters.The software converts the map data into a three-dimensional picture much like a video game. The car's navigation system can then compare these synthetic pictures with the real-world pictures streaming in from a conventional video camera.SourceAlso: See more Software tech briefs.

Posted in: News, Cameras, Lasers & Laser Systems, Photonics


Technology Diagnoses Brain Damage from Concussions, Strokes, and Dementia

New optical diagnostic technology developed at Tufts University School of Engineering promises new ways to identify and monitor brain damage resulting from traumatic injury, stroke, or vascular dementia in real time and without invasive procedures.

Posted in: News, Electronic Components, Diagnostics, Fiber Optics, Optics, Photonics, Measuring Instruments


New Serenity Payload Detects Hostile Fire

Two government-developed sensors are working together to increase the security of deployed soldiers. The Firefly and Serenity sensors employ government developed algorithms, software, and hardware to locate hostile fire around a base. The technology, a joint effort between the Army Aviation Research, Development and Engineering Center, or AMRDEC, and the Army Research Lab, referred to as ARL, has been under development for more than a decade.

Posted in: News, Cameras, Optics, Photonics, Detectors, Sensors


NASA Advances Next-Generation 3D-Imaging Lidar

Building, fixing, and refueling space-based assets or rendezvousing with a comet or asteroid will require a robotic vehicle and a super-precise, high-resolution 3D imaging lidar that will generate real-time images needed to guide the vehicle to a target traveling at thousands of miles per hour. A team at NASA’s Goddard Space Flight Center is developing a next-generation 3D scanning lidar — dubbed the Goddard Reconfiguable Solid-state Scanning Lidar (GRSSLi) — that could provide the imagery needed to execute these orbital dances. GRSSLi is a small, low-cost, low-weight platform capable of centimeter-level resolution over a range of distances, from meters to kilometers. Equipped with a low-power, eye-safe laser; a MEMS scanner; and a single photodetector, GRSSLi will "paint" a scene with the scanning laser, and its detector will sense the reflected light to create a high-resolution 3D image at kilometer distances. A non-scanning version of GRSSLi would be ideal for close approaches to asteroids. It would employ a flash lidar, which doesn’t paint a scene with a mechanical scanner, but rather illuminates the target with a single pulse of laser light — much like a camera flash. Source:

Posted in: News, Lasers & Laser Systems, Photonics, Machinery & Automation, Robotics


Adaptive Zoom Riflescope Prototype Has Push-Button Magnification

When an Army Special Forces officer‑turned engineer puts his mind to designing a military riflescope, he doesn’t forget the importance of creating something for the soldiers who will carry it that is easy to use, extremely accurate, light‑weight and has long‑lasting battery power. The result is the Rapid Adaptive Zoom for Assault Rifles (RAZAR) prototype, developed by Sandia National Laboratories optical engineer Brett Bagwell. At the push of a button, RAZAR can toggle between high and low magnifications, enabling soldiers to zoom in without having to remove their eyes from their targets or their hands from their rifles.

Posted in: News, Optics, Photonics


Researchers Measure Stress in 3D-Printed Metal Parts

Lawrence Livermore National Laboratory researchers have developed an efficient method to measure residual stress in metal parts produced by powder-bed fusion additive manufacturing (AM).The 3D-printing process produces metal parts layer by layer using a high-energy laser beam to fuse metal powder particles. When each layer is complete, the build platform moves downward by the thickness of one layer, and a new powder layer is spread on the previous layer.While the method produces quality parts and components, residual stress is a major problem during the fabrication process. Large temperature changes near the last melt spot, and the repetition of this process, result in localized expansion and contraction.An LLNL research team, led by engineer Amanda Wu, has developed an accurate residual stress measurement method that combines traditional stress-relieving methods (destructive analysis) with modern technology: digital image correlation (DIC). The process provides fast and accurate measurements of surface-level residual stresses in AM parts.The team used DIC to produce a set of quantified residual stress data for AM, exploring laser parameters. DIC is a cost-effective, image analysis method in which a dual camera setup is used to photograph an AM part once before it’s removed from the build plate for analysis and once after. The part is imaged, removed, and then re-imaged to measure the external residual stress.SourceAlso: Learn about Design and Analysis of Metal-to-Composite Nozzle Extension Joints.

Posted in: News, Cameras, Rapid Prototyping & Tooling, Metals, Lasers & Laser Systems, Photonics, Measuring Instruments