Vehicle Detection Sensors
The ability to reliably detect vehicles offers significant advantages for asset management, resource allocation, site safety and traffic control.
Identifying the right technology for your vehicle detection application can be challenging, and many factors must be taken into consideration, including task, size of target, sensing range, sensor mounting, and whether the application is primarily indoor or outdoor.
Radar sensors are ideal for long-range outdoor applications. Unlike photoelectric or ultrasonic sensors, radar sensors are not affected by conditions such as wind, rain, fog, light, humidity and air temperature. This results in accurate detection in outdoor environments. Many sensors can also be configured to detect objects up to a specified distance, ignoring objects beyond the set point, resulting in higher accuracy. Furthermore, while inductive and capacitive sensors can detect only moving targets, radar sensors can detect vehicles that are both stationary and in motion.
Optical Sensor (Infrared)
Compared to other technologies, optical sensors are not used as frequently for vehicle detection, but they can be a good option for some applications. An opposed mode optical sensor uses the interruption of a light beam between an emitter and a receiver to detect objects. For example, the presence of a vehicle passing between the emitter and the receiver breaks the beam of light. This technology can be used to detect whether a vehicle has completely exited a car wash.
Measuring Light Grid
Measuring light grids are often used for vehicle detection to start and stop a transaction (e.g., paying a toll at a tollbooth). A sender and a receiver are installed on either side of a toll lane, stretching an array of light beams across the lane. When a vehicle enters the detection area, data from each beam can be used to determine vehicle class and the number of axles with a high level of accuracy.
Compare Vehicle Detection Technologies
|Max Sensing Range||Size of Target
||Depends on the size of target||All sizes||Can be installed above or below grade|
|Wireless Ultrasonic Sensor||4 meters||All sizes||Must be mounted overhead|
|Radar Sensor||40 meters||Large, predictable targets (e.g. trains)||Minimum of 6 feet from target
|Optical Sensor (Infrared)||200 meters||5 millimeters or greater
||Requires mounting for both emitter and receiver|
|Measuring Light Grid||2 meters
||All sizes||Requires mounting for both emitter and receiver|