This study involved the preparation of dense Ti-10wt.%Mo alloys using selective laser melting (SLM) with a powder combination of pure titanium (Ti) and pure molybdenum (Mo). Integrating temperature stress numerical simulations and actual data elucidates the correlation between linear laser energy density and residual stress. The impact of linear energy density on the surface roughness, densification behavior, microstructural development, and mechanical properties of SLM-processed Ti-10Mo components was also examined. As linear energy density diminished from 0.125 J/mm to 0.233 J/mm, surface roughness reduced from 18.2 μm to 4.4 μm, while relative compactness increased from 94.9% to 99.8%, respectively. It is necessary to reduce the friction between the puncture needle or implant needle and human tissue, enhancing comfort and precision. The microstructural investigation revealed that SLM-processed Ti-10Mo alloys consist of a phase combination of hexagonal tight-packed (hcp) α-Ti and body-centered cubic (bcc) β-Ti, with heterogeneous conchoidal microstructures found in the samples. Furthermore, as the laser energy input increased, Mo powder particles were mostly fully melted, leading to a significant rise in the microhardness value. The as-built Ti-10Mo alloys exhibited a high ultimate tensile strength of 860 MPa and an elongation of 32.9% at a linear laser energy density of 0.15 J/mm, with the fracture morphology indicating a mixed fracture mode mostly characterized by ductile fracture. This research can enhance the prospective bio-application of Ti-Mo alloys.

Background: With the continuous development of medical robots, they have become a powerful tool for surgery and treatment. A prostate brachytherapy robot is a kind of robot widely used in prostate cancer treatment; its main function is to accurately implant radioactive seeds into prostate tissue to kill cancer cells. Using prostate brachytherapy robots for surgery can reduce damage to surrounding tissue during surgery, thereby reducing the risk of external electrolysis and metastasis of tumor cells. Objective: This study aimed to design a prostate brachytherapy robot that is more in line with practical usage needs, based on the method of manually performing prostate brachytherapy surgery in clinical practice. Finally, its feasibility has been demonstrated through brachytherapy experiments. Methods: Firstly, the actual requirements for prostate particle implantation surgery have been analyzed, which has been followed by reviewing previous literature and patents to determine the design scheme of the robot. Finally, SOLIDWORKS software has been used for mechanical design of the robot, and the control system of the robot has been designed based on Arduino. Results: A robotic arm type prostate particle implantation robot has been successfully designed. We have installed a visual module on the prostate particle implantation robot, which has enabled the robot system to have image transmission monitoring function to assist in the calibration of the puncture position before surgery. Finally, we have employed other sensors to complete the particle implantation experiment, and successfully confirmed its superiority through comparing errors. Conclusion: This work has analyzed and studied the clinical process of prostate particle implantation surgery, and designed a prostate particle implantation robot, including the mechanical design and control system design of the robot. We have also simulated the scene of prostate particle implantation surgery in the human body through particle implantation experiments, and successfully and accurately implanted radioactive particles to the target. The experimental results have proven the feasibility of the robot. We have made improvements in execution efficiency by using a parallelogram-based robotic arm as the representation of the prostate particle implantation robot and equipped it with a visual module. The visual module collects a video stream of the puncture needle's perspective and provides feedback to the control end to assist in the calibration of the puncture position before surgery, greatly reducing the probability of secondary injury to patients.

Introduction: Biomimetic flexible arms, with their outstanding flexibility, excellent environmental adaptability, and high flexibility, have shown broad application prospects in fields such as healthcare, detection, robotics, and human-computer interaction. Especially in minimally invasive surgery, disaster rescue, and complex environments, biomimetic flexible arms, as a new and efficient tool, have enormous market potential. This study takes the brachiopod octopus as a biomimetic blueprint and designs a control system for a biomimetic flexible arm based on control requirements. Methods: Based on the study of its mechanical structure and biological characteristics, a biomimetic flexible robotic arm driven by shape memory alloy (SMA) wires has been developed. We also proposed an SMA actuator linkage vector control method to achieve bending of flexible robot arms in any direction and angle. Results: We have successfully developed a biomimetic flexible arm prototype and built an experimental platform to test the motion and control performance of the flexible robotic arm. Discussion: The results of this study provide new ideas for the application of flexible robots in medical, rescue, and complex environments. Compared with traditional rigid robots, the design of biomimetic flexible arms not only improves the adaptability and flexibility of robots but also provides possibilities for their operation in narrow spaces. This innovation can significantly improve the operational accuracy of robots in minimally invasive surgery and other fields, thereby enhancing patient safety and surgical outcomes. Meanwhile, due to the fact that the experimental prototype in this study was handmade, there were significant differences in the prestress of the three groups of SMA wires during the installation process, which affected the control effect. And when we designed the SMA actuator linkage vector control strategy, multiple idealized assumptions were made, but these assumptions are difficult to fully implement in practical operation, resulting in deviations between experimental results and expectations. Conclusion: The maximum bending angle of the flexible robotic arm that we designed is 24 degrees. The variation law of the bending angle of the robot arm with voltage and time was obtained through experiments, and the experimental results were in good agreement with the theoretical analysis. The related achievements have been patented.