Types and Working Principles of Vehicle Perception Sensors

There are various types of automotive sensors, which can be classified into multiple types based on the physical quantities they detect and their working principles. Common automotive sensors include temperature sensors, pressure sensors, speed sensors, position sensors, oxygen sensors, acceleration sensors, and gyroscopes.

1. Temperature sensor: Temperature sensors are mainly used to measure the temperature of key parts such as engines, transmissions, and cooling systems. Common temperature sensors include thermocouples, thermistors, and infrared temperature sensors.

1) Thermocouples utilize the thermoelectric effect of two different metal conductors to convert temperature changes into voltage signals;

2) Thermistors utilize the temperature dependent properties of semiconductor materials to convert temperature changes into resistance signals;

3) Infrared temperature sensors calculate temperature by measuring the infrared radiation intensity of objects and are suitable for non-contact temperature measurement.

2. Pressure sensor: Pressure sensors are used to measure oil pressure, tire pressure, and intake manifold pressure. Common pressure sensors include resistive sensors, capacitive sensors, and piezoelectric sensors. The piezoresistive sensor utilizes the characteristic of the resistance of semiconductor materials changing with pressure to convert pressure changes into resistance signals; Capacitive sensors utilize the characteristic of the capacitance value of capacitors changing with pressure to convert pressure changes into capacitance signals; Piezoelectric sensors utilize the piezoelectric effect of certain materials to convert pressure changes into voltage signals.

3. Speed sensor: The speed sensor is used to measure wheel speed and engine speed, etc. Common speed sensors include Hall effect sensors and magneto electric sensors. Hall effect sensors utilize the Hall effect of Hall elements in a magnetic field to convert rotational speed into voltage signals; Magnetic electric sensors use the principle of electromagnetic induction to convert rotational speed into voltage signals.

4. Position sensor: The position sensor is used to measure throttle position, accelerator pedal position, steering angle, etc. Common position sensors include potentiometer sensors, Hall effect sensors, and photoelectric sensors. Potentiometer sensors utilize the characteristic of potentiometer resistance changing with position to convert position changes into resistance signals; Hall effect sensors utilize the Hall effect of Hall elements in a magnetic field to convert position changes into voltage signals; The photoelectric sensor utilizes the photoelectric effect to convert position changes into voltage signals.

5. Oxygen sensor: The oxygen sensor is used to measure the concentration of oxygen in the exhaust to control the air-fuel ratio of the engine. Common oxygen sensors include zirconia sensors and titanium oxide sensors. Zirconia sensors utilize the oxygen ion conductivity of zirconia ceramics to convert changes in oxygen concentration into voltage signals; The titanium oxide sensor utilizes the characteristic of the resistance of titanium oxide material changing with oxygen concentration to convert the change in oxygen concentration into a resistance signal.