A Tool for Accelerometer Modeling

    Accelerometers are integral part of the science instrument payloads of space based gravimetry and gravitational wave measurements. These are either used to detect the actuating forces on the body of the spacecraft, to enable a drag-free scenario where a test mass will follow a geodesic, or combined in pairs as to build a gradiometer. From a technological standpoint, different techniques have been used to measure the acceleration, from capacitance reading, to optical interferometry, to cold atom interferometry. As the next generation gravimetry missions are considered, there is a need to assist the design of this instrument, preferentially without having to recreate a model for each family of devices within the same framework, in order to simulate its performance and to enable the best science return.
    
    Here is presented a tool to model and simulate accelerometers. This comprises a Simulink library containing the components and their associated Matlab scripts. It is being developed to be modular, parametric, agnostic in respect of measurement technique, flexible in the mode of operation of the instrument, and instantiable to accommodate scenarios with multiple accelerometers on one or more spacecrafts. This tool can run as a standalone simulation, with multiple arbitrary generated noise inputs to obtain the overall noise budget and also can be integrated with XHPS, a Simulink library that simulates satellite dynamics with high precision gravity field models, to calculate the in-flight instrument sensitivity.