Empirical formula and experiment based force modeling for haptic spine surgery simulation

Realistic force modeling of bone drilling is critical to haptic simulation systems for precise surgical training such as pedicle screw fixation in spine surgery. Existing method of force modeling applied metal machining theory to bone drilling directly. However, the mechanical property of bony material is different from continuous metal. In this paper, we present a novel force modeling method of bone drilling based on empirical formula and drilling experiment to provide a force model with high fidelity. A simplified empirical model of drilling in bony material is derived from the empirical formula of metal drilling. To determine the parameters in our empirical model, we construct an experimental system and perform a group of drilling experiments on real bones. We implement our force model in a group of drilling simulations and compare the computational force with the original experimental data to testify its validity.