An apparatus comprises a sensor comprising a left camera and a right camera. A processor is coupled to the sensor. The processor is configured to produce an image and disparity data for the image, and search for a vertical object within the image using the disparity data. The processor is also configured to determine whether the vertical object is a bale of material using the image, and compute an orientation of the bale relative to the sensor using the disparity data. The sensor and processor can be mounted for use on an autonomous bale mover comprising an integral power system, a ground-drive system, a bale loading system, and a bale carrying system.