Category Archives: Sensors

Piq: This Ski-sensor Measures Details of your Skiing

Most skiers want feedback about their skiing, for improving their technique. The ski sensor from Rossignol offers one that not only does what skiers want in unprecedented detail, but also light and tiny enough to be unobtrusive. For instance, you get details about edge-to-edge transition time, in-air rotation, g-force, airtime and more. The sensor is slick enough and low profile, so you may not even notice that you have it on you.

This multi-sport ski sensor, Piq, measures just 44 x 38 x 5.4 mm. In the three-piece setup, the largest is the AA-battery sized charging unit. When not in use, you can simply plug this into the USB port of your computer and leave it for charging. It has a steel clamp to allow the Piq sensor to snap under it when you are resting. This gives the Piq sensor a quick recharge during say, lunchtime. In real use, the Piq sensor stays in a small pocket on the ankle strap that you strap around your ankle. You must be careful when you wrap and strap the ankle strap to prevent the Piq sensor from flying out during some of the most aggressive sessions.

Once you have had it on securely, you can forget about the Piq. Those who tried it on for multiple days, say the Piq never budged, even when the skier straight-lined it at over 100 kmph, jumped, skied corn snow, groomers, hard pack, and deep powder. In general, whether you slash, thrash, and even smash a few gates, this tiny, light, and secure Piq sensor will stay with you.

The Piq sensor has its own battery, powering it on for continuous tracking for about three hours, according to the manufacturer. In actual practice, the battery lasts longer than the manufacturer’s claim, before needing a recharge. This is indeed a big plus for the Piq, as it is very rare for the battery performance in a device to exceed the manufacturer’s claims.

While you are on the snow, the Piq sensor will track and record several statistics such as your speed, rotation time in the air, total airtime, G-force when you land, and the G-force when you take a turn. It will record your edge-to-edge transition time and the angulation of your ski in a turn, generally known as the carving degree. You can time your skiing time, as against standing or riding the chair, etc., your total run, and all your motions including the turns and jumps during the session. Piq will even count the turns per minute when you are skiing.

A free Android or iOS app companion allows the user to get access to the data the Piq sensor has acquired. No cable connection is necessary, as the smartphone connects to the sensor via Bluetooth 4.0. However, the app does not give you the data in real-time. Rather, it synchronizes your session when you trigger the specific function within the app.

An interactive, info-graphic style interface displays the data you pulled in and allows you to look at topline data for the session. You can then drill down to specifics about your turns and jumps.

Sleep Better with a Raspberry Pi

Sleep is an integral part of our lives, and lack of quality sleep quickly leads to a whole host of issues related to physical, emotional, behavioral, etc. Quality sleep is linked to a good environment that includes proper bedding, clothing, temperature, humidity, and lighting among other things. Although electronics may not be able to help much with the proper choice of bedding and clothing, a cheap but versatile single board computer such as the RBPi or Raspberry Pi is a good contender for controlling temperature, humidity and lighting during sleep hours.

When using the RBPi for controlling the environment of the bedroom, it is necessary to build an RBPi-based temperature-monitoring network in the house. This helps to get some hard data on the existing temperature trends at different places, so it will be easy to know whether the solutions tried did actually work. Since temperature is to be monitored at different places at the same time, it is necessary to use remote sensors.

You can use temperature sensors such as the single-wire DS18B20 thermometers for inexpensive and accurate temperature measurement. This model has two types of sensors – transistor-sized and waterproof, and you can use either for the purpose. However, people have found the waterproof sensors were easier to position and calibrate, and they were slightly more accurate as well.

Testing the sensors on the RBPi is simple as this SBC supports the DS18B20 sensors by the built-in w1-gpio library. The RBPi allows easy readouts of the 1-Wire devices. You can wire up a few DS18B20s to multiple RBPI, Model A+ and position them at all main parts of the house. It also helps to integrate data from your Nest Thermostat API, if you are using this and collect the local outdoor temperature data as well – use the Weather Underground, for instance. Monitor the temperatures from the different sensors on a rolling 24-hour graph, and you can make out if there is a trend.

It is possible to even out temperature variations in the house by sealing vents and leakages in areas where the temperature dips. However, this may not be enough to raise the temperature to comfortable levels at locations distant from central heating ducts. Moreover, not all walls of the house may receive equal amounts of sunlight, and this may be another reason for the temperature dropping in certain rooms after sunset.

You can use unobtrusive wall-mounted space heaters to boost the temperature up in these areas. Usually, these are slabs of stone with heating wires running through them. Stone has high thermal capacity, meaning it retains and radiates heat for a long time. This arrangement is also safe for use in children’s bedrooms. When used on a thermostat-triggered outlet, the heater only turns on at a select temperature that you choose. You can fine-tune the settings after monitoring the temperature data for a couple of nights.

This project is useful if you are planning to have an extended network, with remote-controlled HVAC using branch air ducts. Individual controls on the branch ducts can control the airflow, so the system efficiency goes up, such as by turning down the airflow to sections of the house where there is no one present.

How Smart Sensor Technology helps Beehives

Plants are necessary for life on the planet Earth, as they transform the gas Carbon-Di-Oxide that animals exhale into life-sustaining Oxygen. Plants, in turn, depend largely on bees to pollinate their flowers and propagate thereby. That makes honey bees a keystone species, which humans have recognized throughout history. Bees help to pollinate nearly 70% of all plants on earth assuring about 30% of the global food supply. That makes bees a predictor of our planet’s future health.

Global warning has brought with it an alarming rise in the growth rates of damaging pathogens such as fungi, viruses and mites. At the same time, there has been a serious disrupt in the natural rhythms that the bee population had adapted over centuries of consistent seasonal weather patterns. Crop production is infested with pesticides, which bees ingest and transmit back to their hives during pollination. This often leads to a total collapse of colonies. Electromagnetic radiation level in the atmosphere is rising with the exponential growth of cell phones and wireless communication towers. This interferes with the ability of the bees to navigate in flight.

All the above has made it imperative for scientists to monitor the activity of honey bees within their hives in the daytime as well as at night including during inclement weather. At the University College of Cork in Ireland, a group of food business, embedded systems engineering and biology students have recently taken up the challenge. They have developed a unique platform for monitoring, collecting and analyzing activity of bees within the colonies unobtrusively.

The project Smart Beehive has earned top honors in the Smarter Planet Challenge 2014 of IEEE/IBM. Using mobile technology, the project deploys big data, wireless sensor networks and cloud computing for recording and uploading encrypted data.

Waspmote is a modular hardware sensor platform. Libelium has developed Waspmote for any sensor network and wireless technology to connect to any cloud platform. The UCC team of students has used Waspmote as their starting point along with integrated hive condition and gas sensors. They have used ZigBee radios, GSM and 3G communications to study the impact of oxygen, carbon dioxide, humidity, temperature, airborne dust levels and chemical pollutants on the honey bees. The students captured data from initial observations in two scientific papers and three invention disclosures.

According to the famous physicist Albert Einstein, man can survive only for four years on earth if there were no bees left. Smart technology can integrate beehive sensors and analyze the data they collect. Therefore, such platforms play a critical role not only in ensuring continuation of pollination, but also in ultimately monitoring, understanding and managing the precious global resources as well.

The Plug & Sense! Technology from the Libelium Waspmote wireless sensor platform offers the use of a wide range of sensors, integrating more than 70 of them at a time. It can adapt to any scenario of monitoring with wireless sensors such as water quality, vineyard monitoring, livestock tracking, irrigation control, air and noise pollution, etc.

Outdoor deployment is possible because of the waterproof enclosures used by Plug & Sense! Moreover, using solar panels, the honeybee project has the ability to harvest energy.

Waspmote Plug & Sense! : Solar-Powered Wireless Sensor Platforms

Today, we use sensors for a myriad of activities such as intrusion detection, fall detection, patient surveillance, art and goods preservation, offspring care, animal tracking, selective irrigation, and many more. Where the sensor network has to operate outdoors, what can be a better way of powering them other than through solar means?

Using an external or internal solar panel, one can safely recharge batteries for the system. For external solar panels, the panel is usually mounted on a holder tilted at a suitable angle ensuring the maximum performance of the outdoor installation. When space is a major challenge, such as indoors, the solar panel can be embedded on the front of the enclosure. Typical rechargeable batteries used for powering loads are rated 6600mAh, and this ensures the sensors do not stop working even when the sun is not providing adequate light.

Such platforms of wireless sensor networks provide solutions for Smart Cities. Waspmote Plug & Sense! from Libelium is a system of encapsulated wireless sensor devices that allow system integrators to implement modular wireless sensor networks in a scalable manner. The Libelium system reduces the installation from days to just hours.

Each node of a Waspmote Plug & Sense! comes with six connectors. You can connect sensor probes to these connectors directly and the system is ready to install and easy to deploy. Using connectors ensures that the services remain scalable and sustainable. The possibility of powering the platform through solar power allows energy harvesting and years of autonomy.

Once the sensors have been installed, the nodes on the Waspmote Plug & Sense! can be programmed wirelessly. This is possible because of the special feature, OTAP or Over The Air Programming, incorporated into the platform. Thanks to OTAP, users can replace or add sensors without having to uninstall any of the nodes. This helps to keep the maintenance levels within reasonable limits. For example, to extend the service, you can easily add a noise sensor to a network consisting of CO2 probes, simply by attaching it.

The applications are endless for the Waspmote Plug & Sense! platforms. Apart from Smart Cities, the models are preconfigured for creating other widely applicable services out of the box, such as radiation control, ambient control, smart security, air quality, smart agriculture, smart parking and so many more.

You can use these sensor platforms anywhere in the world, as they use the generally available radio frequencies 2.4GHz and 868/900MHz, besides complying with certification standards such as CE, FCC, and IC. Usually, these sensor platforms send information to a sensor gateway that in turn, uploads the data to a cloud service. Therefore, the data is accessible from anywhere in the world and users can integrate it easily into third-party applications.

Use of solar-powered wireless sensor networks makes it so easy for adding a new sensor that municipalities find they do not have to reinstall the network for Smart Cities. The solution reduces the complexity of the installation and its maintenance, while providing it with a high degree of scalability. Available with IP65 enclosures for outdoor deployment and no software license fees, these platforms offer remarkable opportunities.

Different Types of Light Sensors

Light falling on to the surface of a light sensor generates an electrical output proportional to the strength of the incident illumination. The sensor responds to a band of radiant energy existing within a narrow range of frequencies in the electromagnetic spectrum, which we characterize as light. These frequencies range from the infrared to the visible and continue to the ultraviolet region of the spectrum.

Most light sensors are passive devices for converting the light energy of the spectrum into electrical signal. Light sensors are also known as photo sensors or photoelectric devices, since they convert photons into electrons. We can group photoelectric devices into two main categories. One generates electricity when illuminated – such as photovoltaic or photo-emissive, etc. and the other changes their electrical properties in some way – such as photo-resistors or photo-conductors, etc. Accordingly, the following classification emerges.

Photo-emissive cells

These are formed from light sensitive material such as cesium. When struck by a photon of sufficient energy, the light sensitive material releases free electrons. As high frequency light contains photons of higher energy, they have a better chance of producing more electrical energy.

Photo-conductive cells

The electrical resistance of these cells varies when subjected to light. They are made of semiconductor material and the light hitting it causes photoconductivity, which controls the current flow through the material. Cadmium Sulphide is the most common material for making photo-conductive cells, such as the light dependent resistor or LDR.

Photo-voltaic cells

These generate an EMF or electromotive force proportional to the radiant light energy falling. Although similar in effect to the photo-emissive cells, these are made up of two semiconductor materials sandwiched together. Solar cells are the most common photovoltaic cells in existence.

Photo-junction devices

These photo-devices are made of true semiconductor devices such as PN-junctions that use light for controlling the flow of electrons and holes. Specifically designed for light penetration and detection applications, their spectral responses are tuned to the wavelength of light expected to be incident on the device.

Applications of light sensors

LDR photocell: The Cadmium Sulphide photo-resistive cell is the most common example of this device. The resistance of these cells when not illuminated is of the order of 10M ohms, which reduces to the level of 100 ohms when fully lit or illuminated. As the voltage drop across a resistor increases with its resistance value, an LDR photocell can generate different voltages in a potential divider circuit based on the amount of light falling on it.

Light activated switch: This is basically a dark sensing circuit, with a light sensor in series with a potentiometer forming one arm of a simple resistance bridge network and two fixed resistors forming the other side of the bridge. By changing the potentiometer, one can balance the bridge when the light sensor is illuminated, for example by sunlight. The absence of sunlight causes the bridge to unbalance and the resulting potential difference is amplified by an operational amplifier to operate a relay or a switch.

Today, it is common to find cameras that do not operate with a film, but with charge coupled devices that convert the light falling on them to an electronic image.

MEMS Technology Helps To Measure Flow

Smart technologies are creating compact and lightweight sensing elements. Apart from being optimal, fast, and efficient solutions, these are not limited to only the data input functions as the conventional sensing technologies are. Rather, they integrate the areas of sensing and control while offering high-value information that humans or systems can subsequently process. Several unique and advanced technologies such as MEMS form the concept of sensing and control expertise. For example, flow sensors use the ButterflyMEMS technology to operate.

Flow sensors using the MEMS technology operate with major advantages. For example, they can easily measure flow speed ranging from 1 mm per second to 40 m per second. To understand this better, ButterflyMEMS technology can sense the fluttering of the wings of a butterfly and the roar of a typhoon with equal ease. A tiny MEMS flow sensor does all the work and it is the size of a 1.5 mm square chip, which is only 0.4 mm thick.

Conventionally, flow sensors have been using the method of resistance measurement. The method senses the change in electrical resistance of a filament because of a change in temperature caused by the flow of material across the filament. Balancing the resistance of the filament is a time-consuming method, which forms the major disadvantage of this method and makes it expensive.

In contrast, the MEMS flow sensor utilizes a thermopile, an element that converts thermal energy into electrical energy. This technology offers several advantages not seen earlier. For instance, MEMS technology offers cheaper operation, only a few adjustments, high sensitivity, and low power consumption.

This advanced sensor can even sense the direction of flow. The chip has two sets of thermopiles located on either side of a tiny heater element. The thermopiles measure the deviations in heat symmetry that the gas flow causes. The chip senses the direction of flow based on a positive or a negative deviation. A thin layer of insulating film covers the sensor chip and protects it from being exposed to the gas.

In the absence of flow, temperature distribution remains uniform around the heater and there is no differential voltage between the two thermopiles. With even the smallest flow, the heat symmetry collapses, as the thermopile on the side of the heater facing the flow shows a lower temperature, while the thermopile on the other side is warmer. This temperature difference causes a differential voltage to appear between the two thermopiles. This voltage is proportional to the mass flow rate.

The superb characteristic of the sensing chip comes from an unusual shape created by a unique etching technology. Compared to the conventional silicon etching, this unique etching technology creates a larger sensing area in the same volume. This results in a cavity design enabling heating with greater efficiency while keeping the power consumption low. Additionally, the cross-point of temperature characteristic can be factory adjusted, which results in high output stability even when the ambient temperature fluctuates.

Within the actual sensor, a set of screens in the sensor inlet produces a uniform, laminar flow through the sensor offering optimal mass flow readings. An orifice in the outlet side of the sensor buffers against pulsing flows.

Differential Pressure with a Tiny Sensor

Process control requires system operators to monitor and control the condition and movement of liquids and gases. Several instruments are available for this, allowing measurement and monitoring of variables, and these fall under the categories of pressure, temperature, level, and flow. Among the pressure-gage category, differential-pressure gages receive the widest recognition for being the largest specialty type – useful in filtration, flow, and level measurements.

While standard pressure gages measure pressure at a single point in a system, differential pressure gages measure pressures at two points and display the difference on a single dial. This makes it easy for the operator to know at a glance, which of the two points is at a higher pressure, and by how much. Use of differential pressure gages greatly reduces operator error, protecting expensive equipment. They reduce operator training and maintenance time, thereby improving process efficiency.

For instance, differential pressure gages are popularly applied in filtration. In this process, a filter separates unwanted contaminants or particles from a gas or liquid system. However, with the progress of the process, the filter becomes increasingly clogged, leading to a drop in efficiency and pressure at the outlet.

It would seem enough to use a single standard pressure gage at the outlet to monitor the health of the filter and assess the time for its inspection and replacement. However, the situation is complicated, as most processes do not maintain a steady working pressure. Several factors are responsible for this, such as compressor or pump on-off cycles or valve open-close cycles, causing wide pressure fluctuations in most processes. For many systems, operators expect such fluctuations of pressure as normal, within limits.

Using two standard pressure gages, one at the input and the other at the output, introduces two additional problems for the operator. First, this compounds the accuracy errors resulting from the two gages as against error from one gage. Second, the operator needs training in reading the two gages, then subtracting the readings, and finally, interpreting the result. History shows many operators do not truly understand the importance of the calculation.

Installing one differential pressure gage using the same taps at the filter inlet and outlet solves all the problems listed above. The accuracy goes up as the rate of error drops. Additionally, the operator does not have to rely on mathematics to understand and interpret the reading – most differential pressure gage dials feature a red arc to indicate the clogging of the filter.

The SDP3x differential pressure sensor from Sensirion is a tiny device. Its dimensions are only 5x8x5 mm, making it one of the smallest of its kind, but with countless new possibilities of applications. It is well suited for use in portable medical devices as well as in consumer electronics.

Users can choose between an analog signal output and a digital one from two versions of the fully calibrated and temperature-compensated differential pressure sensor. The digital sensor, the SDP31, comes with an I2C interface, while the analog sensor, the SDP36, offers an analog output signal. The sensors have a sampling rate of 2 KHz with a resolution of 16-bits, and a measurement range of +/-500 Pa with a span accuracy of 3% of the reading.

Digital Temperature Sensor with High Accuracy

Whether it is the body temperature, room temperature or the average temperature of the day, we take important decisions based on the various temperatures we measure and record. Although the mercury-based thermometer is still the most commonly used instrument, industrial temperature measurement has largely shifted to electronic sensors, data logging and digital displays. Accuracy in measurement is highly desirable and sensor manufacturers are constantly improving on their products offering better quality.

Sensirion is one of the world’s leading manufacturers of temperature and humidity sensors. Their new digital temperature sensor STS3x offers high accuracy. The tiny eight-pin DFN package of the STS3x is 0.9 mm high and measures only 2.5 x 2.5 mm across. Sensirion has based the STS3x on the same chip as their existing SHT3x humidity sensor. Because of its tiny size and wide range of supply voltage – 2.4 to 5.5 V – users can integrate the STS3x in a large variety of applications. The sensor is specifically suitable for battery-operated devices, as it consumes very low power – typically 6.6µW at 3.3V and one measurement per second. Nevertheless, it delivers outstanding performance, as it is remarkably accurate at +/-0.3°C, over an extensive temperature range spanning -40°C to +90°C.

Sensirion has based their temperature sensor STS3x on the industry-proven CMOSense technology. Compared to its predecessors, the STS3x has more intelligence, improved accuracy, and greater reliability. Added to this is the very fast start-up and response times of the STS3x, as well as enhanced functionality of high-speed signal processing and communication speeds of up to 1 MHz via two distinctive and user selectable I2C addresses.

Users of STS3x get a temperature sensor that comes pre-calibrated and offers a linearized, digital output, which is compensated for supply voltage instabilities. Sensirion has qualified the STS3x based on JESD 47, according to a dedicated automotive qualification plan certified by AEC Q100. Users have the choice of using the sensor as a watchdog, as it offers an alert option with definable set temperature points – strongly optimizing the overall power consumption. However demanding your data logger may be, and however complicated the temperature compensation of your application, the STS3x is an ideal solution.

Based on its high accuracy, the main target applications of the STS3x are the temperature calibrations in automotive components and body temperature measurement in wearable devices. Other applications that also benefit include a multitude of HVAC devices. This is because of the sensor’s highly accurate temperature data, resulting in precision, power savings, and reliability.

The automotive market benefits from the STS3x sensor solution because of its outstanding quality and low prices – automotive manufacturers can meet stringent emission standards of their industry. The STS3x offers new benchmarks in comfort, safety, and energy consumption. For instance, when combined with humidity sensors, the cabin air inside the vehicle can remain optimally regulated, using climate-controlled seats or air-conditioning. Moreover, by determining the dew point, the air-conditioning of the vehicle may be controlled to eliminate fogging of the windshields, thus ensuring a clear view of the road ahead.

Overall, the STS3x temperature sensors fulfill many stringent requirements of several applications considering cost-effectiveness, performance, and quality.

A Stamp-Sized Radar Sensor from NXP

Radio waves are used for different purposes other than transmitting audio, video and for communication. One of their primary uses includes detecting the presence of objects in the atmosphere, including aircraft, clouds, and precipitation. This is done mainly through Radio Detection and Ranging or RADAR. By noting the time of flight that a single pulse takes to return after reflection from an atmospheric object, it is possible to estimate the distance of the object.

To detect a target, radar systems generate an electromagnetic pulse, focus it, and transmit it using an antenna. Objects in the path of the transmitted pulse scatter most of its energy. However, some of this scattered energy returns to the radar system and is gathered by the same antenna, which then feeds it into a receiver.

The receiver determines the time taken for the pulse to make a round trip from the radar to the target and back. As the electromagnetic pulse travels at the speed of light, its multiplication with the time of travel gives the total distance travelled by the pulse. Therefore, the actual distance to the target is half this total distance.

Manufacturers feel radar is a versatile gadget for use in automobiles. For instance, it can help the driver estimate the distance between his/her vehicle and other objects in front, sides, or back – promoting safer driving. Following this lead, manufacturers have been shrinking the size of the radar system to make it suitable for use in automobiles.

At present, the smallest radar is the 77GHz radar transceiver from NXP Semiconductors N.V. It is a single chip device, roughly the size of a postage stamp. Consequently, manufacturers can place the chip anywhere in the vehicle. This is a very big advantage to vehicle designers, as they are targeting driverless, fully automated driving in the near future, and need increasing numbers of sensors within the vehicle. In fact, Google engineers are already field testing working prototypes of the NXP device for their self-driving cars project.

The reference design from NXP is a 35×35 mm printed circuit board and it has a radar front-end, two MCUs for signal processing, and supporting components. Designers can use this in their self-driving cars, in the form of a cocoon comprising 10-20 tiny radar sensors all around the vehicle to provide a high-resolution, 360-degree view of the environment around it.

ADAS or Advanced Driver Assistance Systems also use radar as their core technology, using it to make driving easier and safer. For instance, they use it for adaptive cruise control, lane change assist warnings, forward collision warnings, blind spot monitoring, emergency braking, and automated braking. According to IHS Research, the market for radar-based ADAS will grow by 23 percent year-on-year, increasing from the current year to more than 50 million radar sensors.

Although alternate technologies presently exist for avoiding collisions, mostly in the form of laser-light and ultrasonics based systems, the 77GHz radar offers a superior performance under adverse conditions such as road grime, fog, and rain. So far, bulky hardware had made it difficult to use radars in vehicles, but not anymore.

PIR Sensor: Let Raspberry Pi Guard your Home

With a versatile platform such as the Raspberry Pi or RBPi, prototyping a project is very simple. The scale does not matter for you can start with a single blinking LED and move on to complex quad copters. If you have the necessary components, simply add a little amount of imagination, and RBPi can work wonders for you.

A practical use for the RBPi is to sense the surrounding environment. Not only is this interesting, but also gathering this data is useful in myriad ways. For example, a weather station uses different sensors to measure pressure, humidity, wind speed and temperature. The main objective in recording and manipulating such data is to predict future weather conditions. Anyone technically savvy can store this data and manipulate it to produce tables and graphs for importing into other applications or projects.

Using a PIR or Passive Infra-Red sensor with an RBPi can be an effective guard for your home. These inexpensive sensors are used with motion activated air fresheners from which, you can easily harvest a couple for building this project. The PIR and RBPi combination can act as an effective burglar alarm in homes and offices.

The PIR sensor effectively sends out a beam of infrared light into the area that it is monitoring. As long as there is no movement in the area, the beam remains undisturbed. However, the slightest movement causes the beam to change, which the PIR sensor can sense. The PIR sensor, when connected to the RBPi, sends it a signal once it detects movement. The RBPi responds to this signal in a manner defined by its program.

For this project, the PIR sensor is set up to watch over an area for any movement. As soon as it detects movement, it triggers the RBPi, which responds by capturing a picture of the event on its camera, including recording a 10-second video at a resolution of 640 x 480 pixels.

Additionally, the RBPi will send out a text message to the owner’s phone, thereby alerting the user of an intruder or whatever that triggered the event. The text message includes the picture and the video. After sending the text, the RBPi will wait for 30 seconds before resuming its watchful stance.

Apart from being an effective burglar alarm, you can use this combination of PIR sensor and RBPi with its camera in many innovative ways. For example, those who like to study birds and their habitat, can set it up near the nest to record the coming and goings of the parent birds.

Using a text message to alert the user is effective, as all phones are capable of receiving SMS. Other methods using emails or tweets usually rely on 3G or Wi-Fi coverage and may not be always useable. Additionally, you can use several alerts from the project simultaneously. The RBPi stores the pictures and video it captures in its memory. You can retrieve them later via any means convenient.

To set up, install the OS in the RBPi, enable the camera via raspi-config and test its working. Use the command “raspistill -o test.jpg” for testing. This produces an image file by the name test.jpg.