High-Resolution River Hydraulic and Water Quality Characterization Using Rapidly Deployable Networked Infomechanical Systems (NIMS RD)

Abstract

Increasing demands on water supplies, non-point source pollution, and water quality-based ecological concerns all point to the need for observing stream flow perturbations and pollutant discharges at higher resolution than was practical in the past. This work presents a rapidly deployable Networked Infomechanical System (NIMS RD) technology for observing spatiotemporal hydraulic and chemical properties across stream channels.NIMS RD is comprised of two supporting towers and a suspension cable delivering power and Internet connectivity for controlling and actuating the tram-like NIMS unit. The NIMS unit is capable of raising and lowering a payload of sensors, allowing a preprogrammed or data-actuated adaptive scan to be completed across a stream channel.In this work, NIMS RD is demonstrated in two relevant cases: (1) elucidating spatiotemporal variations in nutrients and other biologically significant stream constituents in Medea Creek, a small urban stream in Southern California, and (2) using high resolution synoptic sampling of steady velocity and salinity distributions across the San Joaquin River in Central California to provide quantitative salt load estimates. For Medea Creek, temperature and specific conductivity (SC) exhibited varying cross-sectional patterns throughout each of three 24-hour scans carried out over three summer months. Both temperature and SC displayed repeating sinusoidal diel fluctuations independent of the spatial variation. For each of the months the cross-sectional variation was lower during the 2 late nighttime and morning hours than during the afternoon and early nighttime hours. For the San Joaquin River, high resolution velocity distributions from NIMS RD were successfully reproduced in separate deployments, and quantitatively matched stage-based volumetric flow rates at the site. The product of the velocity and associated SC distributions yielded total salt load estimates similar to report values, but no basis for direct comparison was available.

Designing Wireless Sensor Networks as a Shared Resource for Sustainable Development

“…NIMS is also rapidly deployable (Section 4). One NIMS system is currently being used to resolve the spatial distribution in contaminants that results from the mixing of the San Joaquin and Merced rivers [9]. The NIMS node is deployed on a cable attached to two anchor points on either side of the river.…”

Virtual high-resolution for sensor networks

“…Then, installing the available sensor at every 0.5m across the river cross-section along with the deployment infrastructure such as metal trusses to support the sensors in the river is likely to interfere with the nitrate concentration map. On the other hand, a sensor with constrained motion supported via a cable, such as developed in [33], that can move in a 2D plane across the river cross-section, can map the nitrate concentration at the required resolution without interfering significantly with the phenomenon. Assuming the concentration map does not change within the time it takes for the sensor movement to be completed, the nitrate concentration can be mapped at the required resolution 4 .…”

Navigating the Wrench-Feasible C-Space of Cable-Driven Hexapods

“…In recent years, cable-driven parallel mechanisms have been increasingly studied and applied to more and more relevant tasks, such as manipulation of heavy loads [7,20], high-precision positioning [18], monitoring of aquatic environments [4,13], automated construction of civil structures [5], rescue systems [19], or motion simulators [27], among others. Their generally simple design, consisting of a moving platform connected to a fixed base by means of cables that wind up on winches, re-O.…”