14 accepted papers
In this paper, we propose a robotic ultrasound imaging method that scans the breast in two separate phases to acquire high-quality ultrasound images. Our proposed system controls five Degrees of Freedom (DoFs) of the robot that hold an ultrasound probe to perform precise scanning. This system finds…
In this paper, a new remote center of motion (RCM) mechanism is presented whose end-effector is able to move through an entire hemisphere. In general, minimally invasive surgery (MIS) applications, an elliptic cone workspace with vertex angles of 60° and 90° gives the surgeon enough freedom to opera…
Needle insertion is a minimally invasive medical procedure commonly used for biopsy, ablation, or deposition of therapeutic agents. In prostate brachytherapy, needles are inserted into the prostate in order to deposit multiple rice-grain-sized radioactive seeds to eradicate cancerous tissue from clo
Needle insertion is a minimally invasive procedure finding applications in biopsy, ablation, drug delivery, and cancer therapy. Prostate brachytherapy is a therapeutic procedure where radioactive agents are implanted within the prostate using long needles for the purpose of cancer irradiation. Durin
Needle deflection during certain minimally invasive percutaneous procedures, such as prostate biopsy or brachytherapy, is undesired and can be reduced through the use of feedback control. This letter uses a depth-dependent reduced-order three-dimensional (3-D) nonholonomic model of needle tip motion
In this letter, we present a model for needle deflection estimation in soft tissue. The needle is modelled as a vibrating compliant cantilever beam that experiences forces applied by the tissue as it is inserted. Each of the assumed vibration modes are associated with a weighting coefficient whose m
In percutaneous needle insertions, cutting forces at the needle tip deflect the needle and increases targeting error. Thus, modeling needle-tissue interaction in biological tissue is essential for accurate robotics-assisted needle steering. In this letter, dynamics of needle tip interaction with inh
Brachytherapy is a cancer treatment procedure where long needles are inserted toward an inner body target in order to deliver radioactive seeds that treat the cancer cells. Controlling the trajectory of the needle is very challenging as it deviates from a straight path during insertion. In this lett
This letter represents a sliding-based controller for steering beveled-tip needles to stationary locations in soft tissue in a 2-D environment by performing appropriate switches of bevel orientation by 180° axial rotations while the needle is being inserted. Assuming the rotation velocity to be larg
This paper introduces an automatic method to visualize 3D needle shapes for reliable assessment of needle placement during needle insertion procedures. Based on partial observations of the needle within a small sample of 2D transverse ultrasound images, the 3D shape of the entire needle is reconstru…
In needle-based medical procedures, beveled-tip flexible needles are steered inside soft tissue with the aim of reaching pre-defined target locations. The efficiency of needle-based interventions depends on accurate control of the needle tip. This paper presents a comprehensive mechanics-based model…
A tissue-independent model to estimate needle deflection during insertion in soft tissue is presented in this paper. A force/torque sensor is connected to the needle base in order to measure forces and moments during insertion due to needle deflection. A static mechanical model, which is based on th…
This paper represents an extension to the kinematic bicycle model for beveled-tip needle motion in soft tissue, which accounts for non-constant curvature paths for the needle tip. For a tissue that is not stiff relative to the needle, the tissue deformation caused by needle insertion deviates the ne…
We propose a method to estimate the entire shape of a long flexible needle, suitable for a needle insertion assistant robot. This method bases its prediction on only a small segment of a needle, imaged via ultrasound, after insertion. An algorithm is developed that can segment a needle observed part…