Abstract: A system for measuring ocean characteristics. The system includes a sensor assembly and an associated means to control the system buoyancy to achieve cyclic ascent and descent at controlled speeds, either along a mooring line or free-drifting. Buoyancy control is provided by a pump assembly including two rolling diaphragm-sealed, low friction displacement pistons driven by a high torque d.c. motor operated at low speed. There are four functional groups of data gathering instrumentation. The first group measures horizontal water transport, and includes sensors for current (flow velocity), system azimuth, system tilt, and vertical velocity. The second group provides a determination of salinity, and includes sensors for conductivity, temperature and pressure. The third group monitors conditions within the system, and includes sensors for internal temperature and humidity.

Abstract: A system for measuring ocean characteristics. The system includes a sensor assembly and an associated means to control the system buoyancy to achieve cyclic ascent and descent at controlled speeds, either along a mooring line or free-drifting. Buoyancy control is provided by a pump assembly including two rolling diaphragm-sealed, low friction displacement pistons driven by a high torque d.c. motor operated at low speed. There are four functional groups of data gathering instrumentation. The first group measures horizontal water transport, and includes sensors for current (flow velocity), system azimuth, system tilt, and vertical velocity. The second group provides a determination of salinity, and includes sensors for conductivity, temperature and pressure. The third group monitors conditions within the system, and includes sensors for internal temperature and humidity.

Abstract: A system for measurement of ocean current near the surface wave field. The system includes a controlled buoyancy platform having a current sensor. Upper and lower plural roller assemblies are affixed to the platform for limiting platform motion along a guide line. In one form, each guide assembly includes a plurality of rollers adapted to freely track the guide line so that the platform is both substantially free to move along the guide line in response to pressure gradients from the surface wave field and also substantially decoupled from twisting and axial motions of the guide line.

Abstract: Apparatus for measuring the vertical displacement between a remote point and a reference point. The apparatus comprises a pair of reservoirs, each having a liquid working fluid disposed therein, a differential pressure transducer and a hydraulic coupling means for each of the reservoirs. Each hydraulic coupling means couples a point in the reservoir below the top surface of the working fluid to an associated input port of the pressure transducer. A vapor pressure equalization means is provided for the reservoirs whereby the points above the top surface of the working fluid in each reservoir are maintained at substantially equal pressures. The apparatus further includes a volumetric temperature compensation means for offsetting temperature dependent changes in the volume of the working fluids which occur in the hydraulic coupling means.

Abstract: A recording instrument for use in ocean depths and like remote locations and adapted to provide meaningful readings of temperatures and pressure, for example, at such locations over a long period of time without attendance. Analog signals from transducers, which indicate the level of the thing-to-be-measured, are processed to give an averaged digital signal that is then stored on a magnetic tape. The system is battery powered. The instrument detailed is for use at ocean depths where the instrument housing and attachment to a mooring line are of particular importance.