2 and the entire control arrangement is provided with current from an uninterrupted power supply this power supply can store electrical energy in a capacitor 18 of an intermediate condenser circuit 19 which temporarily runs an inverter not shown when line current fails such a condenser 18 thereby keeps guide bar 1 under the control of the main shaft 7 until coming to rest furthermore the position control circuit 11 together with circuit 6 being also referred to as a position control means is provided with collision anticipation means 20 to guard against collisions means 20 comprises a computer 21 which from the position signal values x i and their rate of change can calculate future positions forbidden zones are stored in storage means 22 while some forbidden zones are defined without regard to the phase of the knitting cycle other embodiments may establish conditional zones forbidden at specified phases of the knitting cycle the guide bars are forbidden from entering these zones either permanently or during particular times in the work cycle the computer 21 compares the predicted future positions of the guide bar 1 with these forbidden zones when correlation occurs computer 21 prohibits a further displacement by means of a blocking signal 34 m 34 in actual practice blocks 6 11 14 21 as well as storage areas 13 17 and 22 need not be separate items in fact it is preferred that they should be integrated into the central processing unit cpu z and commercialized as a process computer fig2 illustrates an absolute rotation angle setting transmitter 23 which has a rotating transmitting element 24 element 24 has on its circumference a very finely segmented binary code 25 which.