A number of sensors for measuring distances using infrared light or a laser beam is provided ultrasonic distance sensorsthat are used in various automated applications. Their task is the detection of objects and measuring distance to them. Ultrasonic sensors are used for the operation of the ultrasound, i.e. sound with frequencies that exceed the theoretical range audible to the human ear (i.e., above 20 kHz).
Ultrasonic sensor operating in the range from 2 cm to 200 cm with special bracket for mounting. It is powered with the voltage of 5 V. The output is a signal whose duration is proportional to the measured distance.
Ultrasonic sensor from the DFRobot working in the range of up to 7.5 m. It is powered with the voltage from 3.0 V to 5.5 V. The average supply current is 5 mA, and in the rest mode -14 uA. The sensor also has a temperature compensation.
Ultrasonic sensor from DFRobot operating in the range from 5 cm to 500 cm. It is powered with the voltage from 3.3 V to 5 V. Communication is via serial interface UART (RX, TX) and has an analog and frequency output as well as compensation temperature.
Waterproof ultrasonic sensor operating in the range from 20 cm to 450 cm. It is powered with voltage of 5 V. The output is a signal whose duration is proportional to the measured distance. The sensor is compatible with popular sensor HC-SR04, which means that the sample programs and libraries will work correctly for both sensors.
Kit for self-assembly enabling the addition of ultrasonic scanner function to robot. The sensor is able to scan an area of 120 ° in the range from 10 cm to 400 cm. It consists of a servo, ultrasonic distance sensor and mounting bracket.
Module with ultrasonic sensor URM09 and three measurement ranges to choose from 2 to 150 / 300 / 500 cm. It also allows for a temperature measurement. Supply voltage is from 3.3 V to 5.5 V. The measurement frequency can reach up to 50 Hz. It communicates using the I2C interface.
Ultrasonic sensor operating in the range from 2 cm to 400 cm. It is powered with voltage of 5 V. The output is a signal, duration of which is proportional to the measured distance. Unlike the HC-SR04, it has one additional empty pin.
Module utradźwiękowym a proximity sensor URM09, with a measuring range from 2 cm to 500 cm. the Voltage is from 3.3 V to 5.5 V. the Frequency of measurement can reach up to 30 Hz. Communicates with analog interface.
The principle of ultrasonic distance sensor is in the transmission through the ultrasound transducer and receiving them back, the same as in the case of the laser beam from the laser distance sensors. Based on the difference in time between the sending and receiving of the signal (ultrasound), you can calculate the distance between the sensor and the object from which the reflection of ultrasonic waves. As ultrasonic distance sensors are used in the process of measurement of the audio signal, not light, can be used in applications where photoelectric sensors show difficulties in detection of objects made of plastic and curved surfaces with very good light odbijalności. Ultrasonic sensors are also to withstand any interference of the light environment and the environment, heavily contaminated with dust.
Depending on the application requirements, the ultrasonic sensors can be installed for different devices in different ways. The emission of ultrasonic waves from the sensor is to send them into space, as the laser beam sensor of the photoelectric effect, so that the parallel collaboration of these sensors can go very effectively when performing measurements in environments with a light scattering of sound waves and light. For most applications, using ultrasonic distance sensors in difficult conditions, you should install additional photoelectric sensor to prevent irregular reflections of ultrasonic waves that can seriously falsify the measurement.
It's also worth considering aspects such as the selection of optimal measurement mode depending on the application of the sensor, the required measurement range, output type, measurement information (for example, to connect to analog in of the Arduino, or to the relay control unit, for example, the movement direction of the robot), as well as the shape and material of the housing of the device in which we want to set the ultrasonic distance sensor.