The paper starts from the fundamental of x-ray diffraction (i.e. the essential elements of the instruments, lattice and the measurement real conditions) to provide a consistent base of confidence on the achievable implementation of at distance controlled x-ray diffraction. Metrological approach to the calibration of x-ray diffraction measures and the use of uncertainty of the x-ray diffraction parameters is proposed here as an intermediate objective for real time sound interpretation of information and directive to impart from distance to the controlled diffractometers. The establishment of an extended network of diffractometers/laboratory (i.e the system acting as a reference for monitoring the calibration in several appropriate environment condition) is an other intermediate objective to engine the holistic learning of the whole system. Finally the basic hardware, the solution platform and the graphical user interface of the diffractometers is illustrated in detail to demonstrate that the at distance controlled diffractometers with robotic functioning features is a realistic achievable target.