A work machine includes a frame, a sensor assembly, and an ultrasonic sensor. The frame includes a first portion and a second portion that includes a front bumper and is configured to pivot with respect to the first portion for steering the work machine. The sensor assembly is positioned on the first portion or the second portion of the frame and is configured to sense data for detection of obstacles within a first area around the work machine. The ultrasonic sensor is positioned on the front bumper of the second portion and is configured to sense data for detection of obstacles within a second area around the work machine, the second area outside the first area when the second portion is in an articulated position with respect to the first portion.