Kobler Jan-Philipp, Wall Sergej, Lexow G Jakob, Lang Carl Philipp, Majdani Omid, Kahrs Lüder A, Ortmaier Tobias
Institute of Mechatronic Systems, Leibniz Universität Hannover, 30167, Hanover, Germany.
Hannover Medical School, 30625, Hanover, Germany.
Int J Comput Assist Radiol Surg. 2015 Oct;10(10):1625-37. doi: 10.1007/s11548-015-1153-x. Epub 2015 Feb 12.
During guided drilling for minimally invasive cochlear implantation and related applications, typically forces and torques act on the employed tool guides, which result from both the surgeon's interaction and the bone drilling process. Such loads propagate through the rigid mechanisms and result in deformations of compliant parts, which in turn affect the achievable accuracy. In this paper, the order of magnitude as well as the factors influencing such loads are studied experimentally to facilitate design and optimization of future drill guide prototypes.
The experimental setup to evaluate the occurring loads comprises two six degree of freedom force/torque sensors: one mounted between a manually operated, linearly guided drill handpiece and one below the specimens into which the drilling is carried out. This setup is used to analyze the influences of drilling tool geometry, spindle speed as well as experience of the operator on the resulting loads.
The results reveal that using a spiral drill results in lower process loads compared with a surgical Lindemann mill. Moreover, in this study, an experienced surgeon applied lower interaction forces compared with untrained volunteers. The measured values further indicate that both the intraoperative handling of the bone-attached drill guide as well as the tool removal after completing the hole can be expected to cause temporary load peaks which exceed the values acquired during the drilling procedure itself.
The results obtained using the proposed experimental setup serve as realistic design criteria with respect to the development of future drill guide prototypes. Furthermore, the given values can be used to parameterize simulations for profound stiffness analyses of existing mechanisms.
在微创人工耳蜗植入及相关应用的导向钻孔过程中，通常力和扭矩会作用于所使用的工具导向器上，这是由外科医生的操作以及骨钻孔过程共同产生的。此类载荷通过刚性机构传播，导致柔性部件变形，进而影响可达到的精度。本文通过实验研究此类载荷的量级以及影响因素，以促进未来钻孔导向器原型的设计与优化。
用于评估所产生载荷的实验装置包括两个六自由度力/扭矩传感器：一个安装在手动操作的直线导向钻孔机头之间，另一个安装在进行钻孔的标本下方。该装置用于分析钻孔工具几何形状、主轴转速以及操作员经验对所产生载荷的影响。
结果表明，与手术用林德曼铣刀相比，使用螺旋钻头可降低加工载荷。此外，在本研究中，经验丰富的外科医生施加的相互作用力比未经训练的志愿者要低。测量值还进一步表明，预计在术中处理与骨相连的钻孔导向器以及钻孔完成后取出工具时，都会产生临时载荷峰值，这些峰值超过钻孔过程中本身所获取的值。
使用所提出的实验装置获得的结果可作为未来钻孔导向器原型开发的实际设计标准。此外，给定的值可用于对现有机构进行深度刚度分析的模拟参数化。
