A traffic supervision system for vehicles

To protect and watch transport units consisting of a towing unit and one or more transported or transporting units, the towing unit has a data processing system (1)capable of communicating with the outside world via communications and gps satellites (45)and/or a gsm system (39)and with tags (10b)burried in a road. The transporting otr transported unit or units additionally have a data processing system (15)capable of communicating with a data processing system (1)in the towing unit via a wireless interface (7)or interface (8). The data processing system in the transporting or transported unit or units is moreover interfaced with an aerial (16)capable of communicating with tags in a road or surfaces (10b)or tags (10a)located in the top of transporting ot transported units. A system designed as described above provides the advantage that a cargo or a transport unit can always be positioned and watched.