Bank Drive-through Automobile Detection
There are several possible approaches to solving this application. Photoelectric or ultrasonic sensors may have been used in the past, but both options have drawbacks. Traditional photoelectric sensors would accumulate dirt and dust in the outdoor environment, diminishing reliability, and the sensing ability may be affected by uncontrollable factors such as sunlight, vehicle color and vehicle reflectivity. Ultrasonic sensors would fall victim to wind interference in the outdoor environment. Also, passing vehicles would not provide the large, flat surface that ultrasonic sensors require to accurately detect.
The R-GAGE QT50R Radar Sensor was designed to detect the presence of large moving or stationary objects, regardless of shape or color. Using Frequency Modulated Continuous Wave Radar (FMCW), the QT50R emits and receives swept frequencies through separate antennae, which are captured with a mixer. A digital signal processor then analyzes the signal to determine the presence and distance of an object. The adjustable sensing range gives users the ability to detect objects only within a specified distance, ignoring objects and background beyond the setpoint.
With its robust, dirt-resilient IP67 housing and weather immunity, the sensor is able to withstand harsh winds and other environmental elements, making the R-GAGE QT50R Radar Sensor ideal for use in outdoor applications.
In this application, the QT50R is mounted to the drive-through overhang (within 10 degrees of perpendicular to the ground) and is configured to detect the pavement. When a vehicle blocks the beam, the sensor’s output switches and a signal is sent to the bank workers, alerting them of the presence of the vehicle. This detection method requires a sensor with foreground suppression software, which is available as a special.