Pan American Climate Study (PACS) mooring recovery and deployment cruise report : R/V Thomas Thompson cruise number 73, 28 November to 26 December 1997

Three surface moorings were recovered and redeployed during R/V Thomas Thompson cruise number 73 in the eastern equatorial Pacific as pan of the Pan American Climate Study (PACS). PACS is a NOAA-funded study with the goal of investigating links between sea-surface temperature variability in the tropical oceans near the Americas and climate over the American continents. The three moorings were deployed near 125°W, spanning the strong meridional sea-surface temperature gradient associated with the cold tongue south of the equator and the warmer ocean north of the equator, near the northernmost, summer location of the Intertopical Convergence Zone. The moored array was deployed to improve the understanding of air-sea fluxes and of the processes that control the evolution of the sea surface temperature field in the region. Two surface moorings, located at 3°S, 125°W and lO°N, 125°W, belonging to the Upper Ocean Processes (UOP) Group at the Woods Hole Oceanographic Institution (WHOI), were recovered after being on station for eight months and redeployed. Two eight-month deployments were planned. A third mooring deployed at the equator and 128°W by the Ocean Circulation Group at the University of South Florida (USF) was also recovered and redeployed. The USF mooring, unfortunately, had to be recovered immediately following redeployment due to a problem with the buoy and instrumentation. The buoys of the two WHOI moorings were each equipped with meteorological instrumentation, including a Vector Averaging Wind Recorder (VAWR), and an Improved Meteorological (IMET) system. The WHOI moorings also carried Vector Measuring Current Meters, single point temperature recorders, and conductivity and temperature recorders located in the upper 200 meters of the mooring line. In addition to the instrumentation noted above, a variety of other instruments, including an acoustic current meter, acoustic doppler current meters, bio-optical instrument packages and an acoustic rain gauge, were deployed during the PACS field program. The USF mooring had an IMET system on the surface buoy and for oceanographic instrumentation, two RD Instruments acoustic doppler current profilers (ADCPs), single-point temperature recorders, and conductivity and temperature recorders. Conductivity-temperature-depth (CTD) profiles were made at each mooring site and during the transit between mooring locations. This report describes, in a general manner, the work that took place during R/V Thomas Thompson cruise number 73. A description of the WHOI moored array and instrumentation is provided. Details of the mooring designs and preliminary data from the CTD profies are included.Funding was provided by the National Oceanic and Atmospheric Administration under Contract No. NA66GPO130

An experimental demonstration of effective Curved Layer Fused Filament Fabrication utilising a parallel deposition robot

AbstractFused Filament Fabrication (FFF) is an additive manufacturing (AM) method that relies on the thermal extrusion of a thermoplastic feedstock from a mobile deposition head. Conventional FFF constructs components from stacks of individual extruded layers using tool paths with fixed z-values in each individual layer. Consequently, the manufactured components often contain inherent weaknesses in the z-axis due to the relatively weak thermal fusion bonding that occurs between individual layers, as well as poor surface finish in shallow sloped contours. This study demonstrates the use of Curved Layer FFF (CLFFF) tool paths in tandem with a commercially available parallel, or delta, style FFF system to allow the deposition head to follow the topology of the component. By incorporating a delta robot and CLFFF tool paths in this way, improvements in the surface finish of the manufactured parts has been observed, and time costs associated with Cartesian robot based CLFFF manufacturing have been notably reduced. Furthermore, employing a delta robot provides additional flexibility to CLFFF manufacturing and increases the feasibility of its application for advanced manufacturing. The study has also demonstrated a viable approach to multi-material FFF by decoupling support structure and part manufacture into regions of CLFFF and static z tool pathing in an appropriate fashion