GE Global Research is the research and development division of General Electric. GE Global Research locations include: Global Research Center in Niskayuna, New York, established as the General Electric Research Laboratory in Schenectady in 1900 and relocated to Niskayuna in 1955.This site is also known as the Knolls Laboratory, to distinguish it from the original Schenectady location. It is adjacent to the Knolls Atomic Power Laboratory.John F. Welch Technology Centre in Bangalore, India, established in 2000.
Bisphenol-A polycarbonate (PC) containing pigment particles exhibits distinctive photodegradation patterns after accelerated weathering exposure using a xenon arc lamp. The patterns are caused by diffraction of ultraviolet (UV) light and can be visualized by transmission electron microscopy (TEM) of thin cross sections after staining with RuO4. Paraboloid shapes much larger than the particles are visible in sections made perpendicular to the surface while circular bullseye patterns are seen in slices parallel to the surface. Diffraction patterns can occur because the UV source is relatively compact and the orientation of the source and specimen surface is fixed. No patterns are visible by TEM in samples after outdoor exposure where the UV is more dispersed and the sun/specimen orientation varies with hour and season. Therefore, the patterns are artifacts of the test method. Comparison of published yellowing, physical property change, and erosion rates for pigmented and unpigmented PC after outdoor and xenon arc exposure suggests diffraction has at most a minor effect on the PC photodegradation rate.
There is growing interest in extreme temperature electronics to support instrumentation for sensors at temperatures beyond the normal range of electronics. Reliable packaging in the temperature range of more than 300°C has been demonstrated using ceramic multi-chip modules using conventional hybrid circuit technology. This approach typically requires high NRE costs and lead time. Additive manufacturing processes of ceramics, conductors, and dielectrics provides a digital transformation of hybrid circuit manufacturing technology that reduces time and cost for packaging with the added benefits of novel 3D structures and embedded features. This report extends these materials and direct die interconnect methods to demonstrate RF components that operate in the 300 to 750°C range. Design, fabrication, and testing of resistors, capacitors, and inductors that were printed in 2D and 3D freeform formats are presented.
This paper is about generating motion plans for high degree-of-freedom systems that account for both static and dynamic collisions along the entire body. A particular class of mathematical programs with complementarity constraints become useful in this regard. Optimization-based planners can tackle confined space trajectory planning while being cognizant of robot and (mostly static) obstacle constraints. However, handling moving obstacles is non-trivial in a real-time setting. To this end, we present the FLIQC (Fast LInear Quadratic Complementarity based) motion planner. Our reactive planner employs a novel motion model that captures the entire rigid robot as well as the obstacle geometry and ensures non-penetration between the surfaces due to the imposed constraint. We perform thorough comparative studies with the state-of-the-art, which demonstrate improved performance. Extensive simulation and hardware experiments validate our claim of generating continuous and real-time motion plans at 1 kHz for modern collaborative robots with constant minimal parameters.
Pneumatic artificial muscles (PAMs) consist of an elastomeric bladder wrapped in a Kevlar braid. When inflated, PAMs expand radially and contract axially, producing large axial forces. PAMs are often utilized for their high specific work and specific power, as well as their ability to produce large axial displacements. Although the axial behavior of PAMs is well understood, the radial behavior has remained under-utilized and is poorly understood. Radial expansion in large diameter (over 2 inches) PAMs has recently been used in worm-like robots to create anchoring forces that allow for a peristaltic wave which creates locomotion through acrylic pipes. By radially expanding, the PAM presses itself into the pipe, creating an anchor point. The previously anchored PAM then deflates, which propels the robot forward. Modeling of the radial expansion forces and anchoring was desired to determine the pressurization required for proper anchoring before slipping occurs due to the combined robot and payload weight. Modeling was performed using a force balance approach to capture the effects that bladder strain and applied axial load has on the anchoring force. Radial expansion testing was performed to validate the model. Force due to anchoring was recorded using force transducers attached to sections of acrylic pipe using an MTS servo-hydraulic testing machine. Data from the test was compared to the predicted anchoring force.
