Instrumented assembly screw

A system for determining the tightening torque of an assembly screw including an assembly screw and an RFID reader including an RFID antenna and an RFID chip to receive the electrical resistance value delivered by the strain gage of the assembly screw, a processing module to determine a tightening torque from this electrical resistance value, and a display to display the determined tightening torque, wherein the assembly screw includes at least a threaded part and a non-threaded part, the non-threaded part being equipped with a strain gage sensitive to the instantaneous elongation of the non-threaded part and with an RFID tag connected to the strain gage by a wired link, in order to allow the wireless transmission of an electrical resistance value of the strain gage representative of the instantaneous elongation, wherein the strain gage is printed on the non-threaded part of the assembly screw and in that the RFID tag is printed on the non-threaded part of the assembly screw, and in that the RFID reader includes sonic or light-emitting means to provide an alert in the event of loss of tightening.