Abstract: An apparatus and associated method, the apparatus comprising a controlled element (10), such as a robotic manipulator, and a dynamically updatable control system (11). The control system (11) uses a control system equation (eq. (1)) to determine control signals (dq/dt) for controlling the controlled element (1) given any required inputs (q, V) to the control system equation (eq. (1)). The control system (11) is dynamically updatable in that in response to a script file indicating a code structure (11d) preferably having linked nodes (12a 13a-c) and representing at least some components (W,F,&agr;,&bgr;) of the control system equation (eq. (1)), the control system (11) creates the code structure (11d), at run-time, and does so such that the nodes (12a 13a-c) can be queried (i.e. are executable logic) to provide values for at least some components (W,F,&agr;,&bgr;) of the control system equation (eq. (1)).