603415 A milking arrangement using a milking robot (10) is disclosed. One known problem of industrial robots is the phenomenon of singularities. A singularity occurs in a joint of a multilink robot when the acceleration of one link would be infinite. In other words, a singularity means that the robot can choose between two or more different link positions to reach an arbitrary position in the three dimensional workspace. If a singularity occurs, the industrial robot can run out of control, and is thus not safe. The robot comprises a first link L1), a second link (L2), a third link (L3), an end effector (14), sensor (16) and a control unit (15). The first link is rotatable to a first angle within a first angle range (&alpha1) via a first joint (11). The second link is rotatable to a second angle within a second angle range (&alpha2) via a second joint (12). The third link (L3) is rotatable to a third angle within a third angle range (&alpha3) via third joint (13), The links (L1, L2, L3) are rotatable so that the end effector is movable within a three-dimensional workspace. Each position of the end effector within the workspace corresponds to a single combination of the first, second and third angles. The sensor is used to determine the location of a target, such as the teat of a milking animal, so that the effector may be directed there by the control unit. By such a restriction to the movements of the first, second and third link it can be ensured that no singularity can occur. The milking robot according to the invention is thus safe in the sense that the movement of the links to any arbitrary position within the workspace can be predicted. Restriction of the movement is achieved by limiting the number of axes (degrees of freedom) and/or by limiting the angle ranges. Thanks to the limited number of links, the manufacturing costs of the milking robot can be relatively low, and the design can be relatively light and simple.
