Navcon provides several programs that automate the process of calibrating accelerometers using the Keysight 35670A FFT Dyanamic Signal Analyzer. Here is a brief description of the programs available. Follow the Related Links for more information.

HCAL Hand-Held Calibration - This I-basic program can perform an end-to-end calibration of the transducer and input channel of the data acquisition system. A hand-held calibrator is a small, portable, battery- powered device.

RCAL Ratio Calibration - With this method, the frequency response of a large inertial mass is measured by mounting an accelerometer on one side of it and impacting on the other side. The calibration FRF can be used as a calibration curve or a single, averaged value can be determined for a given frequency range as a calibration value.

DCAL (Drop Calibration) - Drop calibration, which is also known as free-fall calibration, is a very basic and natural method of calibrating accelerometers and force sensors. It is based on a predictable and repeatable motion, that a body in free-fall experiences a constant gravitational acceleration, and by measuring the step response of the transducer to the one-g input, its sensitivity is determined. An actual drop calibration response differs from the ideal free-fall step response in several aspects, and the measured data is curve-fit to determine the sensitivity. Drop calibration is an absolute calibration method and does not require a reference standard because the results are referenced to the local gravitational constant.

MRIT (Multiple Reference Impact Testing) - Multiple Reference Impact Testing (MRIT) does not imply impacting a test structure with more than one hammer. Instead, the outputs are taken as the references, rather than the input. MRIT is a modal data acquisition method in which frequency response functions (FRF) are measured between a single, roving impactor and multiple, fixed response transducers. Possible reference transducers are accelerometers, microphones, and proximity probes. A set of multiple reference FRFs is generated by applying the reciprocity relationships to determine the response at the impact locations. The set of measurements can then be treated as multiple input data and processed with multiple reference modal parameter estimation software.