A robotic arm maneuvers a teat preparation cup and executes instructions from a robotic arm controller. The controller comprises an interface, a memory, and a processor. The processor instructs the sensor to perform a first scan. If the first scan discovers a first set of teats, the processor moves the robotic arm a first distance and instructs the sensor to perform a second scan. If the second scan discovers a second set of teats, the processor moves the robotic arm to a location under the first teat, and instructs the sensor to perform a third scan. The processor determines if the third scan discovers a third set of teats. If each of the first set, second set, and third set of discovered teats comprises the first teat, the processor instructs the robotic arm to attach the preparation cup to the first teat.