Force Feedback Control of a Robotic Needle Insertion into Layered Soft Tissues

In this study, a feedback control law is proposed to steer a robotic needle using force information from a fiber optic sensor. This sensor is integrated into the lumen at the distal end of the needle to measure the needle insertion force. The force signals are analyzed via wavelet transform to identify the boundaries of layered soft tissues in real time. The boundaries information is then used in the robotic needle steering scheme to reduce as much as possible the insertion force, and mitigate the risk of tissue injury. Porcine belly tissue phantoms are herein used in the ex vivo tests of robotic needle insertion, and comparative study has been done with and without insertion force feedback. Experimental results show that the force feedback control approach proposed reduces effectively the insertion force.