3Type of sensors

The best idea of the types of sensors and their applications in the home environments describes the figure (Fig. 3.1) with model installation of the whole system. For better illustration several types of sensors and other equipment were used that are followed their description.

image
Fig. 3.1 – Example of smart home

An essential element in the system installation is the control unit, otherwise referred to as a HomeHUB or Access Point (AP in the figure). The access point is the common name for home routers used in households for connecting devices to the Internet.

Some manufacturers therefore try to broaden the functionality of these devices towards smart home. In some cases it is even possible to upgrade to the new firmware to support the smart home functionality. The assumption for this is that the other peripheral equipments (e.g. sensors) are connected by a wireless technology that is supported by AP. However this is related mostly to WiFi technology, which is very demanding to power supply and the associated battery life of the sensor. So this method is not ideal. The most common solution currently is adding AP to the existing home router and to connect them together via Ethernet.

The control unit is usually provided directly by a smart home services provider or through the sales network. From a technical perspective, the choice of appropriate AP influences used sensors that have to support the same wireless communication.

Now we will go through sensors used in the figure (Fig. 3.1).

Movement sensor called also PIR sensor is one of the most common sensors. It fulfills not only comfort needs (automatic turn on/off lights) but also security needs (monitoring area in case of absence). These sensors are in the market for a few years as part of dedicated security systems, connected to the control unit via the already pre-prepared infrastructure in the apartment. The current trend is to control the sensors wirelessly, with the possibility of placement anywhere in the home.

Smoke and fire sensor can be part of one peripheral. While the smoke sensor checks the conductivity change to detect the presence of smoke or gas in the room, fire sensor works on the principle of temperature sensors.

The temperature sensor was previously and currently is part of other sensors. This approach has not changed and the temperature sensor can be found for example, as part of door magnetic contact or PIR sensor.

The magnetic sensor is simple and well known sensor used in security systems for monitoring entrance or balcony door to the apartment, working on the principle of controlling contact through magnet controlled microswitch.

IR generator (bar) can be used as so-called infrared wall for protection e.g. the balcony area or even in the comfort mode as part of the entry garage door. Start the selected action is caused by interruption of the light flow between receiver and transmitter diode.

SOS button is actually very simple driver which triggers the appropriate action. In this case the button can fulfill the role of callingduf help. Button may be as a part of the bracelet on the arm of an older family member. The supply of bracelet in this case can be settled by the simple lithium battery, since sending a signal happens only when you press.

The cameras are mainly the domain of security systems and are mostly used for this purpose. These peripherals require continuous power supply, no independent battery power as the main source is used. Their use is wide and also for the monitoring of movement of older or smaller family member in the absence or in the next room.

Lighting control can also be realized by wireless switches, intelligent dimmers responsive to the touch. Due to greater comfort simple controller is installed in every room. Cheaper solution is a combination of existing switches with the actuator, which is controlled wirelessly.

Thermostat belongs to the controllers designed to control the temperature in a room or at home. Using of existing thermostats installed in the apartment can be problematic. Therefore its replacement solves application on the tablet or touch control panel. The thermostat can also contain a temperature sensor.

Drapery control, multifunction controls are mostly simple, single-purpose remote controls designed to control a particular case, i.e., curtains or even lighting. Their advantage is ease of use (older persons who may have a touch panel problem).

The touch control panel is a universal remote control that can operate and control any device connected to the system via the application. It allows you to set scenes and program a sequence of events. Currently these types of remote conrol are replaced by selfphones or smartphones.

Data storage is designed to store multimedia content (video, audio, photo) and also serves as a storage server for recordings from cameras. It can also be used to backup data from other devices in the home (PC, tablet, smartphone).

TV or Smart TV can play multimedia content in addition to serve as a monitor for the installed cameras, as well as lighting control via special application while viewing the desired content.

Mobile user end device are in terms of smart home remote control system as well as the devices connected to the home network that can access the multimedia content.

External conditions impact on process management

Influence of external conditions on the process management means mainly energy management. Managing energy consumption is the main motivator for implementing home automation system in homes. Second place belongs to the safety and comfort of users.

image
Fig. 4.1 – Energy management

Energy management is particularly the effective use of renewable energy sources when supplying electrical appliances during favorable weather conditions combined with the power distribution system. The system in this case effectively regulates the use of these resources in order to minimize withdrawals from a distribution system.

In the area of solar panels significant progress was made. This advanced technology manufacture solar panels that are cost-competitive with conventional collector, designed primarily for heating water. This means that electricity derived from solar conversion can solve the problem of hot water used at homes, while at the same time it is possible to power by the energy other appliances.

A novelty is also the improvement of production technology of battery cells, which essentially revolutionized the ability to store the energy generated during the day and use this energy at night for heating or lighting, or during the next day to cool the interior.

Use of renewable sources in combination with intelligent electrometers offers plenty possibilities for energy management.

Home automation systems can manage energy consumption for heating by measuring not only the interior and exterior temperatures, but in combination with electrically operated exterior shutters to regulate the conditions in the interior and at the same time saving energy required to illuminate the space. The combination of these criteria is using the correct user interface and good control algorithm by the very simple choice of the user.

Energy management domain was in an industrial area and with the arrival of home automation systems gaining popularity amongst end consumers.