|
In industrial measurement, often take a long time, large-scale, multi-channel data measurement system. In the field of environmental monitoring in the field, the special circumstances due to environmental conditions, often because of the monitoring system Power supply , The existence of long-distance cabling and other factors is difficult to deploy effectively. The wireless sensor network because of its low-power, self-organizing routing without the need for wiring and other characteristics, especially suitable for field measurements in industrial areas. This article describes a deployment in China's southern coastal city of a case of wireless sensor networks, the system is a small amount of modifications to meet the needs of many industrial measurement. Presence in the city a lot of mountain landscapes, urban population, required to maintain high utilization of land, so a large number of buildings and roads are located near the mountains. Perennial high rainfall in the area, especially in the summer rainy season every year, there will be a lot of rainfall. Instability of the mountain landscape on erosion by rain, prone to landslides, lives and property of residents pose a huge threat. Too many sets of local authorities try to deploy the monitoring of wired networks to the mountain landslide monitoring and early warning, but often as the inaccessible areas as monitoring of the mountain, the lack of roads, field wiring, power supply and so restricted, so cable system is very difficult to deploy. In addition, the deployment of wire, often with the nearest way Datalogger data collection, monitoring required hand regularly to download data, systems are not real-time data, poor flexibility. This, experts in multiple geographic monitoring the exchange, and conduct field visits on several occasions after, Crossbow companies based on wireless sensor networks to monitor landslide complete wireless solution. Basic measurement principle Landslide monitoring rely mainly on the role of two sensors: liquid level sensors and angle sensors. Risk-prone in the mountain region along the mountain to set up multiple vertical holes, shown in Figure 1. Each hole will be deployed at the bottom of a liquid level sensor, the depth of the deployment of a number of different angle sensors. Since the landslide area phenomenon created by water erosion, and therefore the depth of water table is identified landslide hazard of the first indicators. The data from the deployment in the bottom of the liquid level sensor hole capture by the wireless network to send. Each target monitoring area is from 10 to 20 nodes constitute a (adjusted according to specific circumstances), the entire project area by the number of monitoring form, as Crossbow's Xserver middleware server capabilities, the system constitutes a flexible and adjustable (including subnets within the network number and the number of nodes). The distance between adjacent nodes is about 20 ~ 100m, data collection interval can be flexibly controlled by the central server, during the dry season can be adjusted to every 24 hours once the data collection and transmission, thereby saving energy and avoiding a lot of redundant data. Dangerous period in the rainy season, the collection interval to 2 minutes can be intensive in order to ensure real-time monitoring and warning capabilities. System supports two-way data transfer, all the data together to the base station, connected to the upper layer for data integration of IT systems to facilitate the management and query. Sensor nodes Each sensor node contains the liquid level sensor and angle sensor element, IRIS wireless sensor network node, MDA300 data acquisition boards and Battery Group. MDA300 ADC provides 8 channels, 8 digital channels and the I2C interface is used for various types of external sensors. In this project, tilt sensor voltage output is 0 ~ 5V, MDA300 reserved by the resistor divider network to provide easy access to the MDA300 of 0 ~ 2.5VADC interfaces. Liquid level sensor was 4 ~ 20mA current output, an external battery pack through the simulation of an ideal voltage source, and then use the resistor divider network 124? Redundant resistance can be converted to ADC 4 ~ 20mA 0 ~ 2.5V can be collected voltage signal. MDA300 is configured to a liquid level sensor channels and six angle sensor channels. Relay Mote Relay and Mote Mote hardware exactly the same structure, but not connected sensors. Different from ordinary Mote, Mote is not battery-powered relay, but the form of electricity through the cable, always keep in working condition to ensure the whole network Communicate Efficiency. Mote will relay the data from the node to the base station through the Mesh network transmission. When a Mote failure, associated with other Mote will automatically re-select the route. Troubleshooting in the Mote, it will re-join the Mesh network to continue working. Base station Stargate base station by a gateway and a Mote composition. Stargate gateway contains IntelPXA255 the main processor, IntelSA1111 coprocessor, 64MBRAM, 32MBFLASH and 51 pin connectors, PCMCIA Interface, CF interfaces. In the project, Stargate by an IRIS 51-pin interface node, since the set of protocols for relying Xmesh subnet data; external GPRS via PCMCIA cards, rely on GPRS networks for remote communication capabilities. Base station's own processing power used for data preprocessing, CF card interface, external 512MBFLASH at least 7 days to save the data locally. The base station in-kind shown in Figure 5. Netcom Letter. Crossbow in the development of this project several times sent before the site visits, and a detailed discussion and analysis, concluded that the most appropriate for the environment 2.4GHz. I am an expert from turnstile-gate.com, while we provides the quality product, such as Parking Control System Manufacturer , Turnstile Gate Manufacturer, Door Access Controller,and more.
Related Articles -
Parking Control System Manufacturer, Turnstile Gate Manufacturer,
|
