Method and device for generating a 3D model of a bearing structure of an escalator or a moving walkway

A method and a device are described for measuring structural components of a bearing structure of an escalator or moving walkway without specialized personnel having to carry out precise measurements in situ. The method comprises fixing an image recording device on a conveying means of the escalator, removing at least one of the tread units of the escalator in order to enable visual access to structural components beneath it; moving the conveying means together with the image recording device at least over partial areas of a travel path, recording images of the structural components to be measured with the image recording device, and generating a 3D model of at least a partial area of the structural components of the bearing structure based on the recorded images. Using the 3D model experts can then measure dimensions and spatial arrangements of structural components without having to be in person at the actual location.