Force sensors based on distortion in delay lines

The principle of operation of force sensors based on distortion in delay lines type of sensor is the distortion of an acoustic signal, in a pulse-excited magnetostrictive delay line due to a force applied at any point between the point where the pulse is generated and the receiving coil. A conductor orthogonal to the delay line is used for pulsed current transmission and its distance is fixed with respect to the delay line. The input and the output of the system are the applied force on the delay line support and the amplitude of the detected output V _o, respectively. Under fixed amplitude of the pulsed current, V_o has a maximum value under zero input and decreases as the applied force increases. Experimental results show that the response of the sensor is a monotonic, exponential function of the applied force. A method is also proposed, according to which an integrated sensor array could be made based on this principle