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This paper presents a haptic needle manipulation simulator for Chinese acupuncture learning and training. Students can learn and practise acupuncture in the proposed 3D interactive virtual environment that supports force feedback interface for needle insertion. So that, students not only "see" but also "touch" the virtual patient. With the high performance computers, highly informative and flexible visualization of acupuncture points of various related meridian and collateral can be highlighted to guide the students during training. Such a virtual reality system can provide an interesting and effective learning environment for Chinese acupuncture.

Although venipuncture is one of the most common clinical procedures and is performed by trained medical staff, difficulties arise in 5% of insertion procedures. An instrument that guarantees the insertion of a needle into a vein in a single approach is expected to be beneficial to both medical staff and patients. The next step towards automatic venipuncture is to determine if insertion force feedback can be used, irrespective of insertion speed, insertion angle, or vein depth and diameter. Needle insertion experiments are performed on phantom and porcine tissues to study the interaction between the needle and tissue. A prototype instrument is developed to perform automatic venipuncture on the phantom. From the experiments, we conclude that an increased insertion speed of the needle leads to an increase in insertion force and tissue deformation. Furthermore, distinct force peaks are observed at the penetration of phantom skin and vein, thus enabling automatic detection of phantom vein puncture.

The rotational motion has been utilized in several medical needle technologies to enhance the capability of cutting tissue. The needle rotation helps significantly reduce the tissue cutting force, which improves procedure outcome and pain. However, the needle rotation can also incur tissue winding that intensifies tissue damage, which results in complications of bleeding and hematoma. Some histological observations showed that bidirectional needle rotation could reduce the tissue damage caused by tissue winding. In this study, we established a cohesive surface based finite element model to evaluate the cutting force in needle insertion with unidirectional and bidirectional rotation. The simulation results suggested that the frequency of switching direction of needle rotation insignificantly influences the cutting force. The Latin Hypercube method was used to generate a response surface of cutting force and locate the minimum at the insertion speed of 1mm/s combined with the slice/push ratio of 1.9. In clinical use, we suggested that the needle speeds can be first selected to optimize the cutting force according to the type of target tissue. If the desired needle rotation is high, a proper switching frequency can be applied to reduce the tissue winding damage without increasing the cutting force.

Robotic-assisted steered needles aim to accurately control the deflection of the flexible needle’s tip to achieve accurate path following. In doing so, they can decrease trauma to the patient, by avoiding sensitive regions while increasing placement accuracy. This class of needle presents more complicated kinematics compared to straight needles, which can be exploited to produce specific motion profiles via careful controller design and tuning. Motion profiles can be optimized to minimize certain conditions such as maximum tissue deformation and target migration, which was the goal of the formalized cyclic, low-level controller for a Programmable Bevel-tip Needle (PBN) presented in this work. PBNs are composed of a number of interlocked segments that are able to slide with respect to one another. Producing a controlled, desired offset of the tip geometry leads to the corresponding desired curvature of the PBN, and hence desired path trajectory of the system. Here, we propose a cyclical actuation strategy, where the tip configuration is achieved over a number of reciprocal motion cycles, which we hypothesize will reduce tissue deformation during the insertion process. A series of in vitro, planar needle insertion experiments are performed in order to compare the cyclic controller performance with the previously used direct push controller, in terms of targeting accuracy and tissue deformation. It is found that there is no significant difference between the target tracking performance of the controllers, but a significant decrease in axial tissue deformation when using the cyclic controller.

Because fine needles can easily be deflected, accurate needle insertion is often difficult. Lower abdominal insertion is particularly difficult because of less imaging feedback; thus, an approach for allowing a straight insertion path by minimizing deflection is beneficial in cases of lower abdominal insertion. Although insertion with axial rotation can minimize deflection, the rotational insertion may cause tissue damage. Therefore, we established a novel insertion method for minimizing both deflection and tissue damage by combining rotation and vibration. Using layered tissues, we evaluated the effect of a combination of rotation and vibration in terms of deflection and tissue damage, which were measured by the insertion force and torque, and the area of the hole created by the needle using histological tissue sections to measure tissue damage. The experimental results demonstrated that insertion with unidirectional rotation is risky in terms of tissue wind-up, while insertion with bidirectional rotation can decrease deflection and avoid wind-up. We also found that insertion with vibration can decrease the insertion force and torque. Therefore, insertion with a combination of bidirectional rotation and vibration can minimize needle deflection and tissue damage, including the insertion force and torque and the hole area.

This paper presents a 3D dynamic trajectory planning method for the insertion of a rigid needle into soft tissue. The optimal needle tip orientation was calculated in which applying an artificial potential field method to determine the 3D distribution of repulsive and attractive forces surrounding the target object and adjacent obstacles, e.g. bones, nerves, or arteries. Soft-tissue deformation occurs dynamically and continuously during the needle insertion. The trajectory planning was therefore temporally discretized, and the compartment searching method used in each time step. This trajectory planning method was then validated by a dynamic finite element method (FEM) simulation. The dynamic finite element model is built for the important displacement parameters of deformation node in needle insertion process. The Mooney–Rivlin material model combined with solid cubic element and an explicit center differencing scheme was used to compute the soft-tissue deformation at each time step and dynamically identify the target and obstacle positions. The proposed trajectory planning method can optimize the insertion path to achieve the target position while avoiding obstacles.

The kinematic relationship between the needle base and the robot's joints is analyzed. The analysis process is based on the aided needle-insertion robot built by our group. The thinking of needle-inserting procedure is confirming the needle base's posture before the needle inserted into tissue. The method of Denavit-Hartenberg (D-H) parameters is used to establish a link robot body-frames with the structural characteristics of the robot. After analysing kinematics, the kinematics equation is presented. The kinematics inverse solutions are obtained with the analytical method and geometry analysis method.