Engineering networks in a threedimensional reference frame

The local level system is the threedimensional reference frame at hand of an experimeter in an engineering network Accordingly we design a threedimensional engineering network paying attention to the spacetime movement of such a local reference frame with respect to a fixed one attached to the datum point. The influence of the change of the local vertical and horizontal reference directions is outlined and numerically documented. Finally the transformation of one local level reference frame into the global equatorial frame of reference, materialized by the input of satellite (GPS) observations within the engineering network, is given. Numerical examples illustrate the set-up of such a satellite-aided or hybrid engineering network.