A leg (205) detection system comprising: a robotic arm (200) comprising a gripping portion (208) for holding a teat cup (203, 210) for attaching to a teat (1102, 1104, 1106, 1108, 203S, 203) of a dairy livestock (200, 202, 203); an imaging system coupled to the robotic arm (200) and configured to capture a first three-dimensional (3D) image (138, 2400, 2500) of a rearview of the dairy livestock (200, 202, 203) in a stall (402), the imaging system comprising a 3D camera (136, 138) or a laser (132), wherein each pixel of the first 3D image (138, 2400, 2500) is associated with a depth value; one or more memory (104) devices configured to store a reference (3D) 3D image (138, 2400, 2500) of the stall (402) without any dairy livestock (200, 202, 203); and a processor (102) communicatively coupled to the imaging system and the one or more memory (104) devices, the processor (102) configured to: access the first 3D image (138, 2400, 2500) and the reference (3D) 3D image (138, 2400, 2500); subtract the first 3D image (138, 2400, 2500) from the reference (3D) 3D image (138, 2400, 2500) to produce a second 3D image (138, 2400, 2500); perform morphological image (138, 2400, 2500) processing on the second 3D image (138, 2400, 2500) to produce a third 3D image (138, 2400, 2500); perform image (138, 2400, 2500) thresholding on the third 3D image (138, 2400, 2500) to produce a fourth 3D image (138, 2400, 2500); cluster (2616, 2618, 2626, 2628) data from the fourth 3D image (138, 2400, 2500); identify, using the clustered data from the fourth 3D image (138, 2400, 2500), one or more legs (205) of the dairy livestock (200, 202, 203); and provide instructions for movements of the robotic arm (200) to avoid the identified one or more legs (205) while attaching the teat cup (203, 210) to the teat (1102, 1104, 1106, 1108, 203S, 203) of the dairy livestock (200, 202, 203).