Position control of trackless vehicle - has positioning circuit switched in to provide current for detection following branching

An automatically controlled trackless vehicle includes a sensing facility for guidance onto a branch path followed by controlled stopping in a selected position. The vehicle contains horizontally and vertically mounted coils in which current is induced by passage over a cable carrying an alternating current. In negotiating a branch line, the vehicle passes along the main cable (L) in which a current (J) flows. At the branch point (WA) switch over occurs to detect a different a.c. signal (JW) in the branch cable. Stopping at a specified point (SP) is provided by remote switching of a positioning circuit that generates a separate current (Jp).