Flexible robotic device for spinal surgery

Abstract

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Predictive mechanics-based model for depth of cut (DOC) of waterjet in soft tissue for waterjet-assisted medical applications

“…(38) shows that depth of cut of waterjet in soft solid has a direct relationship with waterjet velocity and an inverse relationship with penetration pressure. These are in agreement with the experimental results depicted in [33] stating that DOC has a direct relationship with volumetric flow rate of the waterjet (thus the velocity of waterjet), and an inverse relationship with diameter of the waterjet, and sti↵ness of the soft solid. Although decreasing diameter increases the penetration pressure, however, according to (12) as diameter of the waterjet decreases the velocity of the waterjet increases and this increase is more than the increase in penetration pressure.…”

“…Several studies also confirm our results that the depth of waterjet penetration depends on the material properties of the penetrated soft tissue, and characteristics of waterjet [51], [33], [34], [9] and [11]. Seok et al [51] argued that the depth of jet penetration into cadaveric cheeks increases as the velocity, and pressure of the jet increases.…”

“…Recently, waterjets have been used as a surgical tool in waterjet-assisted surgery [9,33,65,45,38,37,52,23,64,3,59,48,58,44,39]. Shi et al [56] has described many advantages that waterjet cutting has over similar approaches to tissue cutting.…”

“…Furthermore, the mechanical properties of the soft tissue were measured at a penetration rate of 1 mm s that is not comparable to the penetration rate of the high-velocity waterjet. Morad et al [33] tried to control the cut depth of waterjet surgical device by controlling the pressure of waterjet; however they stated that while using the waterjet surgical device there is a risk of cutting unwanted tissue layers. They proposed to experimentally tune DOC based on the applied pressure; however they left this to a future study.…”

Concentric joint connectors for form-changing space frames

“…The joints as manufactured (Figure 13) performed very well as part of the octahedral form-changing space frame (Figure 5) and a prototype hexapod manipulator surgical platform developed with Morad (2014) at Imperial College London. It is hoped that they be developed further as key components of multi-strut form-changing space frame structures in the future.…”