We present an optomechanical accelerometer with high dynamic range, high
bandwidth and read-out noise levels below 8 μg/Hz. The
straightforward assembly and low cost of our device make it a prime candidate
for on-site reference calibrations and autonomous navigation. We present
experimental data taken with a vacuum sealed, portable prototype and deduce the
achieved bias stability and scale factor accuracy. Additionally, we present a
comprehensive model of the device physics that we use to analyze the
fundamental noise sources and accuracy limitations of such devices