The ISA accelerometer in view of BepiColombo launch

The BepiColombo Italian Spring Accelerometer (ISA) is a component of the dedicated suite of instruments which will perform the so-called Radio Science Experiments in order to study gravitational field, internal structure and rotational state of the planet Mercury, and to verify important predictions of the general theory of relativity. Its main role is the measurement of non-gravitational accelerations acting on the surface of the Mercury Planetary Orbiter spacecraft, thereby enabling to work on a virtually drag-free satellite. In this talk the concept, design and development of the instrument are reviewed, along with its main scientific products. The development and testing of the data processing procedures, as well as the definition of the instrument operations for the various mission phases, are also presented.