At present, dental implant surgery mainly relies on the clinical experience of the doctor and the assistance of preoperative medical imaging. However, there are some problems in dental implant surgery, such as narrow space, sight obstruction, inaccurate positioning, and high requirements of doctors' proficiency. Therefore, a dental implant robot system (DIRS) guided by optical navigation is developed in this study, with an x-shaped tool and an irregular pentagonal tracer are designed for spatial registration and needle tip positioning strategy respectively. The coordinate system of each unit in DIRS is unified through system calibration, spatial registration, and needle tip positioning strategy. Then the surgical path is planned on the computed tomography (CT) images in the navigation software before operation. The automatic positioning method and the auxiliary positioning method can be used in the operation to achieve accurate positioning and assist doctors to complete the operation. The errors of spatial registration, needle tip positioning strategy, and the overall accuracy of the system were evaluated respectively, and the results showed that they all met the needs of clinical surgery. This study preliminarily verified the feasibility of the precise positioning method for dental surgery robots and provided certain ideas for subsequent related research.

Background Robotic puncture system increasingly demands stringent standard in target location accuracy. The positional and orientational transformation relationships among all components of the system are supposed to be calibrated and identified preoperatively. Aims The target location performance is directly determined by the calibration result. Therefore, a multiple closed‐loops calibration approach is proposed to achieve high‐level calibration accuracy in robotic puncture system. Materials & Methods This method takes as input the three‐dimensional position information of the retro‐reflective markers mounted on the surgical tool, which is detected by the optical tracking system in real time during robotic movement. There is less complicated mathematical derivation and calculation in the presented algorithm by applying the closed‐loop principle. Results Experimental results validate that it can achieve accurate robotic target location with less input data and computation‐cost, satisfying the clinical puncture requirements. Discussion The spatial calibration between robotic arm and optical tracking system efficiently realised by the presented approach present an alternative which can be safely applied to the robotic puncture system for accurate insertion. Conclusion Overall, a multiple closed‐loops calibration approach is proposed in this work, which may increase surgical efficiency.

Puncture robot can improve the accuracy and efficiency of puncture surgery, such as thoracoabdominal and liver puncture. However, as soft tissue is deformed and shifted under respiratory motion and during the puncture process, the needle is pulled, resulting in the needle's bending and deformation, which increases the risks and sufferings of the patient, a robotic puncture system with optical and mechanical feedback is necessary. Therefore, this paper proposes a multi-information sensing 'guide-clamp' end effector for puncture surgery to accurately detect the posture and force on the puncture needle in real time. And gravity bias method with trajectory planning and the compensational controlling model are also proposed to offset the interference of self-weight and achieve zero force following. This system is evaluated by the experiments of robot controlling and human tissue simulation and the results prove the excellent robustness of the system, which meet the clinical requirement.

No abstract

The accuracy of placement during radiotherapy significantly affects treatment quality. During the current and subsequent fractions of radiotherapy treatment (RTT), positional mismatching between the initial CT-scanned location and the current physical state reduces efficiency in RTT. In general, this situation requires doctors to perform freehand adjustment in RTT to adapt the current alteration of patients and guarantee the effectiveness of the plan, which is described as ''plan adapts to tumor,'' and is typically cumbersome. To mitigate such drawback, we designed a morphological robotic system that can keep a patient's posture identical with the first fraction. Furthermore, we directly adjusted nonrigid tumor deformation. Hence, the system achieved high-level matching accuracy between the current and initial physical states, which is notably described as ''tumor adapts to plan.'' Our proposed robotic system consists of a pilot circuit, morphological and mechanical structures, and operating software. A series of experiments was conducted to prove the feasibility and precision of the developed system. Results showed that the proposed robotic system can maintain the same posture as the first fraction. It exhibits the potential to become an efficient solution in radiotherapy.