Patent attributes
An ECU of an object detection device stops transmission of search waves from a plurality of ultrasonic sensors when a vehicle travels at a predetermined speed or more, and counts the frequency of receiving waves with an intensity of not less than a threshold intensity for each of the plurality of ultrasonic sensors. The ECU acquires a first count that is a count of the frequency in a first sensor that is one of the plurality of ultrasonic sensors, and a second count that is a count of the frequency in a second sensor different from the first sensor. The ECU determines that snow accretion has occurred on the first sensor if the first count is smaller than the second count, and a difference between the first count and a representative value that is set based on the second count is not less than a predetermined value.
