Piezo plates are thin sheets of ceramic that can be manufactured to function as a piezo actuators, piezo sensor, or piezo transducers.

In actuators and transducers, when a voltage is applied, the thin layer of piezoceramic deforms and/or vibrates.

A DC voltage will cause the piezo plate to deform.

The MPR121 touch module can read up to 12 channels of touch.

8 channels can also be used to control LEDs.

The module works via I2C and operates at a voltage between 2.5 and 3.6VDC.

Digital Capacitive Touch Switch Sensor Module is based on TTP223B.

Normally, it outputs low and keeps at a low power state.

When a touch is sensed on the circular marked region, it outputs high and switches to the quick response state.

When not being touched for 12 seconds, it switches to a low-power state again.

The Infrared obstacle avoidance sensor has a pair of infrared transmitting and receiving sensors.

The Infrared LED emits infrared signals at certain frequency and when an obstacle appears on the line of infrared light, it is reflected back by the obstacle which is sensed by the receiver.

Magnetic sensing solutions designed for accuracy, sensitivity and reliable measurements of external magnetic fields for compassing and magnetometery.

The three axis option in most widely used to make mechanical parts in manufacturing,industrial work, and architecture.

The process used the three main axes (x,y and z) to shave down the material into the desired shape.

The DHT11 is a basic, ultra low-cost digital temperature and humidity sensor.

It uses a capacitive humidity sensor and a thermistor to measure the surrounding air and spits out a digital signal on the data pin (no analog input pins needed)

DHT11 sensor measures and provides humidity and temprature values serially over a signal wire.

MQ-2 gas sensor (A gas detector is a device that detects the presence of gases in an area, often as part of a safety system.)has high sensitivity to LPG, propane and Hydrogen, also could be used to methane and other combustible steam.

It is with low cost and suitable for different application character.

Configuration Good sensitivity to combustible gas in wide range.

MQ-3 gas sensors has high sensitivity to alchohol, and has good resistance to disturb of gasoline, smoke and vapor.

The sensor could be used to detect alcohol with different concentration, it is with low cost and suitable for different application.

Detecting alcohol, CH4, benzene, gasoline, hexane, CO, and LPG.

MQ4 Methane Gas Sensor detects the concentration of methane gas in the air and ouputs its reading as an analog voltage.

The concentration sensing range of 300 ppm to 10,000 ppm is suitable for leak detection.

For example, the sensor could detect if someone left a gas stove on but not lit.

MQ-5 gas sensor has high sensitity to Methane, Propane and Butane, and could be used to detect both Methane and Propane.

The sensor could be used to detect different combustible gas especially Methane, it is with low cost and suitable for different application.

MQ-6 gas sensor has high sensitity to Propane, Butane and LPG, also response to Natural gas.

The sensor could be used to detect different combustible gas, especially Methane, it is with low cost and suitable for different application.

This is a simple to use carbnon monoxide (CO) sensor, suitable for sensing CO concentrations in the air.

The MQ-7 can detect CO-gas concentrations anywhere from 10 to 500ppm (ppm stands for parts per million.  ppm is Used to express the concentration of a substance which is present in less amount)

This sensor has a high sensitivity and fast response time.

The sensor's output is an analog resistance.

MQ8 hydrogen gas sensor is a Metal oxide semiconductor type sensor.

This sensor is used to detect Hydrogen gas within the air, detect gas leakage, and Hydrogen gas presence within the air.

This sensor is very simple to use and detects hydrogen gas concentration in the range of 100-10000ppm anywhere.

The MQ-135 sensor can be implemented to detect smoke, benzene, vapore and other hazardous gases.

It can detect various harmful gases.

It can be used for air quality monitoring,noxious gas detection, home air pollution detection, industrial pollution detection, portable air pollution detection,etc.

The TSOP sensor is a miniaturised receiver for infrared remote control systems.

PIN diode and pre amplifier are assembled on lead frame and the epoxy package is designed as IR filter.

The demodulated output signal can directly be decode by a microprocessor.

An ultrasonic sensor is an instrument that measures the distance to  an object using ultrasonic sound waves.

An ultrasonic sensor use a transducer to send and receive ultrasonic pulses that relay back information about an object's proximity.

The 3-Axis accelerometer consists of three -5 to +5g accelerometers mounted in one small block.

Using the appropriate data collection hardware and software, you can graph any of these components, or calculate the magnitude of the net acceleration.

PIR (Passive infrared sensor) is an electronic sensor that measures infrared light radiating from an objects in its filed of view.

They are most often used in PIR based motion detectors.

PIR sensor are commonly used in security alarms and automating lighting applications.

PIR sensor used in motion detectors such as automatically triggered lighting devices and protection system that measure devices emitting infrared light in their field of view.

A heart rate monitor is a personal monitoring device that allows one to measure/display heart rate in real time or record the heart rate for later study.

It is largely used to gather heart rate data while performing various types of pysical exercise.

The soil moisture sensor (SMS) is a sensor connected to an irrigation system controller that measures soil moisture content in the active root zone before each sheduled irrigation event and bypasses the cycle set point.

Soil moisture sensors aid good irrigation management.

Capacitive sensing is a technology based on capacitive coupling that can detect and measure anything that is conductive or has a dielectric difference from air.

Capacitive touch screens distinguish and sense specific touch location based on the electrical impulses in a human body,typically the fingertip.

A touch sensor is a type of switch that only operates when it's touched by a charged body.

It has a high-frequency transistor which can conduct electricity when receiving electromagnetic signals.

A raindrop sensor is a board on which nickel is coated in the form of lines.

It works on the principle of resistance.

The raindrop sensor measures the moisture via analog output pins and it provides a digital output when a threshold of moisture exceeds.

The module is based on the LM383 op amp.

A flex sensor is a variable resistor.

It works by increasing the resistance in the circuit the more the component bends.

Spectra symbol has been at the forefront of flex sensor technology since before 1989 and the development of Nintendo's disruptive power glove.

It is used to measure the amount of defection otherwise bending.

The LM35 series are precision integrated circuit temprature devices with an output voltage linearly-proportional to the centrigrade temprature.

A temperature and humidity sensor are low cost-sensitive electronic devices that detects, measures and reports both dampness and air temperature.

The proportion of moisture noticeable all around to the highest amount of moisture at a specific air temperature.

A Force sensor is defined as a transducer that converts an input mechanical load, wright, tention, compression or pressure into an electrical output signal.

Example of force sensors are load cells, pneumatic load cells, capacitive load cells, strain gauge load cells, hydraulic load cells.

Among sensors that detect light, those that  detect the three primary colors of red, green, and blue are called color sensors.

Color sensors detect RGB values by receiving ambient light using a photodiode.

A colour sensor can detect the received light intensity for red, blue and green respectively, making it posible to determine the colour of the target object.

Water flow sensor consists of a copper body, a water rotor, and a hall-effect sensor.

When water flows through the rotor, rotor rolls, its speed changes with different rate of flow. And the hall-effect sensor outputs the corresponding pulse signal.

The sensor works by measuring the cooling effect of the gas passing over a thin, heated wire.

The higher the cooling effect,the higher will be the flow of gas.

In order to be accurate, the sensor needs to know the density of the gas, which is provided to the measurement system by the gas analysis data.

The sound sensor is one type of module used to notice the sound. Generally, this module is used to detect the intensity of sound.

The applications of this module mainly include switch, security, as well as monitoring.

The accuracy of this sensor can be changed for the ease of usage.

The IR sensor array is a device with 7 mounted infrared sensors.

Each IR sensor is capable of detecting black and white colors.

The array is capable of emitting sounds. The IR array can perform detection at proper distances.

Radio frequency identi (RFID) refers to a wireless system comprised of two components:- tags and readers.

The reader is a device that has one or more antennas that emit radio waves and receive signals back from the RFID tag.

Tags, which use radio waves to communicate their identity and other information to nearby readers, can be passive or active.