The aim in this instance was to develop a wireless instrumented laryngoscope to measure direct loads and turning moments about the x (horizontal), y (vertical) and z (transverse) axes of the instrument during use. The neck of the device was machined to give a suitable stiffness and surface to mount strain gauges. An array of twenty-four strain gauges was bonded to the neck of the laryngoscope. Lack of available space required gauges to be bonded in layers. The gauges were wired in full bridge configuration so that the output of 4 gauges were combined for each channel. The device was calibrated by application of known masses (500g - 3000g) through an attachment designed to apply the load only in the relevant plane.
The handle of the laryngoscope was specially modified to contain all of the wireless electronics, as well as a large C cell battery. Overall, the device operated successfully – providing an increased understanding of the loads transmitted during laryngoscopy.