Sobol Sensitivity Analysis, Modeling and Optimization Effective Parameters of Force in Bone Drilling Processes

Bone drilling process is indispensable in orthopedic surgeries and treating bone breakages. It is also very important in dentistry and bone sampling operations. Therefore, bone drilling is one of the most important, common and sensitive processes in biomedical engineering field. Orthopedic surgeries can be improved using robotic bone drilling systems and also mechatronic bone drilling process can be promoted using automatic drilling machines and surgery-assisting robots. Furthermore, imposing higher forces to bone might lead breaking or cracking and consequently serious damage in bone. In this paper a mathematical second order linear regression model is introduced to predict process force behavior during bone drilling process as a function of tool drilling speed, feed rate, tool diameter and effective interactions. Design of experiments using response surface methodology is followed. Then second linear governing equation is assigned to the model and its accuracy is evaluated. Later, Sobol Statistical sensitivity analysis is used to ascertain the effect of process input parameters on process force. Results show that among all effective input parameters tool rotational speed, feed rate and tool diameter have the highest influence on process force respectively. The behavior of each output parameters with variation in each input parameter is further investigated.