Abstract: A method of monitoring relative displacement between two structures using a distance measuring device is provided. The method includes transmitting, using at least one photo-emitter of the distance measuring device, a measurement signal; measuring, using a photo-sensor of the distance measuring device, a time-of-flight of the measurement signal, the time-of-flight being indicative of a distance between the distance measuring device and a component of a first structure, the distance measuring device being attached to a second structure, and the second structure being displaceable relative to the first structure; and transmitting, from a distance measuring device data transmitter to a remote resource using wireless communication, data relating to the displacement of the first structure relative to the second structure.