“ZigBee-enabled meters can communicate and control ZigBee-enabled devices in the home, such as the heating, cooling and air-conditioning systems, to enable utility company programs such as load control, demand response and time-of-use pricing. These programs not only reduce the peak load on the utility grid but also help the home owners make smart decisions about their energy usage,” says Tyagi. Though it might be a while before we see this in India, it is very useful for international service providers who have variable rates for power usage based on the time of the day. Consumption during night or other ‘happy hours’ will be charged less than usual timings; plus consumption by certain devices might be charged more than the others.
The planet’s central nervous system
Sensor technology is so hot today that almost every IT and electronics major has some or the other related project. HP Labs, for instance, announced a very ambitious project late last year. Their dream is to build a ‘central nervous system for the earth’ (CeNSE) that could well be a veritable backbone for the Internet of Things that has been spoken about for so long.
Their goal is to ‘make the earth speak for itself’ using a network of tiny, cheap, robust and very accurate sensors that will give the computers, devices and other tech toys around us the power to sense what is going on in the environment.
Peter Hartwell, senior researcher and team lead for this project, envisions sensing nodes about the size of a pushpin stuck to bridges and buildings to warn of structural strains or weather conditions; scattered along roadsides to monitor traffic, weather and road conditions; embedded in everyday electronics to track hospital equipment, sniff out pesticides and pathogens in food; and so on. Together, the network would make life easier and safer for mankind, while also collecting valuable information that will create awareness for a better tomorrow.
The first goal towards achieving this mega dream is to develop dirt cheap sensors.
Hartwell is working on the first such sensor—an accelerometer that can detect motion and vibration. The device is sensitive enough to detect a heartbeat, and contributes a sense of ‘touch and feel’ to CeNSE. As per details revealed by the company, “The source of that sensitivity is a 5mm2, three-layer silicon chip. A portion of the centre wafer is suspended between the two outer wafers by flexible silicon beams. When the chip moves, the suspended centre lags behind due to its inertia. A measurement of that relative motion is used to calculate the speed, direction and distance the chip has moved. This exquisitely sensitive accelerometer can detect a 10-femtometre change in the position of its centre chip. As a result, it can measure changes to acceleration in the micro-gravity range. That’s about 1000 times more sensitive than accelerometers used in a Wii, an iPhone or an automobile’s airbag system.”
Another interesting development is use of nanomaterials to boost a standard chemical and biological detection technology (Raman spectroscopy) to 100 million times its usual sensitivity rates. As sensitivity rises, sensor size can shrink. That could lead to detectors small enough to clip onto a mobile telephone. “With a wave over produce, the sensor might warn consumers of salmonella on spinach leaves or pesticides present in ‘organic’ produce,” Hartwell says in the press report. It adds the senses of taste and smell to CeNSE.
The team is simultaneously working on adding various other sensors ranging from light and pressure to temperature and humidity.
iphone turned sensor
It seems to be the season for mobile-sensor convergence, and it is not just hobbyists experimenting with such clip-onto-mobile sensors. Jing Li, a physical scientist at NASA’s Ames Research Center, has developed a technology to add low-cost, low-power, high-speed nanosensor-based chemical sensing capabilities to cellphones.
The stamp-sized device can be plugged into an iPhone’s 30-pin dock connector to collect, process and transmit sensor data. It is capable of detecting and identifying low concentrations of airborne ammonia, chlorine gas and methane. According to the NASA report, the device senses chemicals in the air using a ‘sample jet’ and a multiple-channel silicon-based sensing chip which consists of 16 nanosensors, and sends measured data to another phone or a computer via a telephone or Wi-Fi network.
Sensor network for aircraft monitoring
A team at Scotland’s Institute for System Level Integration (iSLI) has started designing a wireless sensor system that could well become a standard feature of the next generation of commercial aircrafts. The project has been launched with a budget of 3.3 million pounds, with contributions from various aerospace industry leaders.
The first prototype wireless sensor network, WiTNESS, will gather complex and accurate data from different parts of the aircraft, which will be used to help identify technical faults, optimise performance and monitor the overall health of the aircraft.
