A system for automatically connecting at least one service line on a truck to a trailer comprising: a receiver suitable for being permanently or temporarily affixed to the trailer the receiver being suitable for being interconnected with at least one of a pneumatic line and an electrical line; a coupling suitable for being manipulated by an end effector of a robotic manipulator to find and engage the receiver when the trailer is brought into proximity with, or hitched to, the truck; a 3D spatial sensing device suitable for being located to face rearward on the truck, so that the 3D sensing device is oriented to sense space beneath an underside of the trailer; and at least one processor that is configured to: in response to a position of the receiver, move the manipulator to align and engage the coupling with the receiver so as to complete a circuit between the truck and the trailer; iteratively identify data points, generated by the 3D sensing device, associated with an image of a kingpin of the trailer; identify point groups from the data points; and estimate a relative location of the kingpin if the point groups match expected shapes and locations of the kingpin; in response to a relative location of the kingpin matching a relative location of the kingpin in a list of relative locations of the kingpin from previous detections, increment a confidence value associated with the relative location of the kingpin in the list; prioritize the list of relative locations of the kingpin from previous detections using the confidence value and proximity to the truck; and output a highest priority relative location of the kingpin from the list for use to guide a backing operation of the truck onto the trailer. a receiver suitable for being permanently or temporarily affixed to the trailer the receiver being suitable for being interconnected with at least one of a pneumatic line and an electrical line; a coupling suitable for being manipulated by an end effector of a robotic manipulator to find and engage the receiver when the trailer is brought into proximity with, or hitched to, the truck; a 3D spatial sensing device suitable for being located to face rearward on the truck, so that the 3D sensing device is oriented to sense space beneath an underside of the trailer; and at least one processor that is configured to: in response to a position of the receiver, move the manipulator to align and engage the coupling with the receiver so as to complete a circuit between the truck and the trailer; iteratively identify data points, generated by the 3D sensing device, associated with an image of a kingpin of the trailer; identify point groups from the data points; and estimate a relative location of the kingpin if the point groups match expected shapes and locations of the kingpin; in response to a relative location of the kingpin matching a relative location of the kingpin in a list of relative locations of the kingpin from previous detections, increment a confidence value associated with the relative location of the kingpin in the list; prioritize the list of relative locations of the kingpin from previous detections using the confidence value and proximity to the truck; and output a highest priority relative location of the kingpin from the list for use to guide a backing operation of the truck onto the trailer. in response to a position of the receiver, move the manipulator to align and engage the coupling with the receiver so as to complete a circuit between the truck and the trailer; iteratively identify data points, generated by the 3D sensing device, associated with an image of a kingpin of the trailer; identify point groups from the data points; and estimate a relative location of the kingpin if the point groups match expected shapes and locations of the kingpin; in response to a relative location of the kingpin matching a relative location of the kingpin in a list of relative locations of the kingpin from previous detections, increment a confidence value associated with the relative location of the kingpin in the list; prioritize the list of relative locations of the kingpin from previous detections using the confidence value and proximity to the truck; and output a highest priority relative location of the kingpin from the list for use to guide a backing operation of the truck onto the trailer.