SCADA, Telematics & GPS Technologies

Carspotting: Part of a mesh network, this sensor node embedded in a San Francisco street can detect when a car parks in the spot beside it. It also monitors passing traffic. See following image credit to Streetline.

This fall, San Francisco will implement the largest mesh network for monitoring parking to date. Around 6,000 wireless sensors from the San Francisco company Streetline will be fixed alongside as many parking spots, monitoring both parking availability and the volume and speed of passing traffic. The city hopes that displaying information from the sensors on Web maps, smart phones, and signs on the street will reduce the traffic and pollution caused by circling cars.

A mesh network differs from a typical wireless network in that there’s no central transmitter: every node can transmit to every other node. Mesh networks have generally been used for environmental monitoring, or to grant wireless devices Internet access.

When sensor networks have been deployed roadside, it’s usually been to monitor traffic, not parking. In urban areas, traffic-monitoring systems have been used for congestion pricing: during business hours in downtown London, for instance, the license plates of cars are photographed, and the drivers are sent a bill. Some parking garages also have signs that tell drivers where the available spaces are, but such systems generally rely on manual car counting, not sensors.

In San Francisco, however, clusters of plastic-encased, networked sensors are embedded in the surface of the street. The main sensor in the cluster, which is commonly used to detect cars, is a magnetic one, says Jim Reich, the vice president of engineering at Streetline. Magnetic sensors detect when a large metal object locally disrupts Earth’s magnetic field. One challenge with magnetic sensors is avoiding false positives. “We rely on the magnetometer the most, but in order to fix errors, we use other types of sensors [that] give you much higher reliability,” says Reich. He won’t elaborate on the supporting sensors, but he says that the Streetline system has a high ninety percent accuracy in recognizing parked cars. (more…)

Avago Technologies announced a new low cost miniature surface mount ambient light photo sensor for controlling display backlighting in a wide range of portable electronic applications. Avago’s APDS-9008, which is designed to approximate the spectral response curve of the human eye, helps to significantly reduce power consumption to extend battery life in mobile phones, PDAs, notebook computers, TVs, video and digital still cameras. Avago is a leading supplier of analog interface components for communications, industrial and consumer applications.

The APDS-9008 is an analog-output ambient light photo sensor that comes in a lead-free miniature chipLED surface mount package. This new sensor from Avago offers a wide voltage range from as low as 1.6 V up to a maximum of 5.5 V and incorporates a spectrally suited photo sensor, which provides excellent responsivity. It targets designers of applications that require the measurement of ambient light to control display backlighting power consumption. Moreover, applications such as mobile phones and PDAs that draw heavy current for backlit LCD displays will benefit from incorporating this surface mount ambient light sensor into their designs.

The APDS-9008 is a pin-to-pin compatible alternative to Avago’s APDS-9005 and provides designers with a miniature low-cost ambient light sensor that can work at a much lower Vcc of 1.6V. (more…)

This is pretty cool, but the name maybe needs a bit of work… just some additional informations about this interesting web service, previously covered in Realtime sensor network awaits your input or output

Pachube (pronounced “patch bay”) is a web service available at http://www.pachube.com that enables people to tag and share real time sensor data from objects, devices and spaces around the world.The key aim is to facilitate interaction between remote environments, both physical and virtual.

Apart from enabling direct connections between any two environments, it can also be used to facilitate many-to-many connections: just like a physical “patch bay” (or telephone switchboard) Pachube enables any participating project to “plug-in” to any other participating project in real time so that, for example, buildings, interactive installations or blogs can “talk” and “respond” to each other.

Source: WSN Blog Link , Original Link

Ahha, no more gang-land activities will taken place since this system installed on your hometown-cities. ShotSpotter is the world leader in gunshot location and detection systems for the public safety and military markets. The company has been delivering patented, state-of-the-art gunshot location and detection solutions for more than a decade.  Every day, officials in more than a dozen cities rely on ShotSpotter systems, with each and every customer a willing reference to our capabilities and results.

A ShotSpotter network includes 12 to 20 sensors per square mile. Roughly the size of a medium pizza, the devices are hidden on rooftops, utility poles, and in other inconspicuous places. Here are the components of a typical unit:

Microphone An internal microphone array gives the sensor 360-degree coverage and makes it possible to determine the direction a sound came from.
GPS Receiver Global positioning satellites give the location of each sensor. GPS also serves as a central clock, making it possible to triangulate an incident’s location based on the speed of sound.
Thermometer Air temperature determines the speed of sound — crucial to calculating a shot’s location. The server at the station checks the Net for other atmospheric conditions that affect sound waves.
Network Connection Each sensor is in constant contact with the server. Some are connected by a telephone line. Others have a digital link managed by a microprocessor.
Memory In sensor units with a processor, if communication is interrupted or bandwidth becomes clogged, the memory stores the sounds until they can be uploaded.

Wired Reviews: Shot Spotter, Ears on the Street, Spotting the Shot

Website: Shotspooter