This project will develop a system to monitor estuarine environmental conditions and disseminate the information on the internet in conjunction with NOAA’s and SECOORA’s Observation Buoy (BOB). We will develop sensors and a communication system which relays the measured information to a web server; these will be installed at the Chesapeake Bay Environmental Center in Maryland. We will develop methods for improving the design of real-time embedded systems and demonstrate them on this system.
We propose to build a low-cost marine RF sensor network infrastructure to monitor data in real-time and upload it to the internet for dissemination. Each node will contain an embedded computer platform to measure and log various types of data. Different node configurations are possible: fixed (e.g. NOAA Basic Observation Buoy, aka BOB) or towed, submerged or above-water nodes. Some nodes may be connected to a network, enabling real-time upload of data to a web server via the internet. Initial devices will use a smartphone to provide the network connection. In the future, the smartphone can be replaced with an embedded network interface in order to lower costs. Reduced functionality stand-alone devices will lack a permanent network connection for cost reasons; they will store data and relay it when requested by a visiting smartphone (or other device) with a network connection. These may eventually include fixed stations, buoys, and vehicles.
We plan to leverage existing technologies to accelerate development of the proof-of-concept phase. Our design decisions will be made to easily support cost reduction design evolution in a follow-on project.
(images courtesy CBEC, NOAA, SECOORA)
An exciting aspect of this proposal is the use of Android-based Motorola Droid smartphones as interface devices. The Android platform provides a broad variety of services: rich user interfaces,extensive processing power, internet communication, ample storage, GPS-based localization, acceleration/orientation sensing. Furthermore, the application will be created with a strong interactive component to capture the attention and imagination of the K-12 students who will use the devices at CBEC. These smartphones will interface wirelessly with embedded nodes (via Bluetooth) to provide additional processing and visualization capabilities. The smartphones also provide both WiFi and 3G cellphone interfaces to the internet, allowing the data to be uploaded in real-time or on-demand.
We will present measured data graphically and numerically on both the smartphones and personal computers via a website. Some data may have a spatial component, so we plan to use modern web services such as Google Earth, making the information presentation more compelling.
We will enhance the RaPTEX toolchain (1) to help the system designer select the best real-time scheduler, and (2) to use real-time scheduling methods to enable the use of noisy, simple switching power supplies with sensitive circuits. We will evaluate these enhancements by applying them to the sensor nodes of the estuarine monitoring system.
The boat computer is built around an M30262F8 microcontroller, four megabytes of flash memory, two RS232 interfaces, and a 160x128 monochrome LCD. It has two main features. First, it displays the boat’s current position and direction on an electronic chart. Second, it logs information from a boat’s GPS receiver and depth sounder in flash memory for off-line analysis.
The chart is displayed on a monochrome LCD which supports three zoom levels. Two megabytes of charts are stored on external flash memory, with resolutions of 160, 65 and 19 feet per pixel, allowing extreme precision in indicating position.
Two megabytes of flash memory are used to log boat position, velocity over ground, track, depth, velocity through water, and battery voltage. This information is then processed off-line to update a high-resolution chart, which is then used to generate updated charts to download to the boat computer.
Waterproof housing. M30262 MCU. Internal GPS. 8 MB Flash memory. Bluetooth-connected depth sounder.
Rests underwater on seabed to measure depth and gather tide data to correct soundings gathered from above dataloggers. M30262 MCU. Motorola pressure sensor. Vinculum VDAP USB drive interface. Triple-ziploc protected against depths of up to 6’! 72 hour battery life with moderate power optimization.