Catheters have been widely used to deal with heart valve diseases. However, the diversity in handle structures and bending curvatures imposes significant complexities in safe delivery and positioning. In this letter, we designed a module for single knob actuation assembled coaxially on the catheter handle, composed of a chuck for universal clamping of diameters from 15 to 45 mm and a position-adjustable shaft to accommodate various spacing between knobs. In addition, we proposed a two-curvature with pseudo joints (TC-PJ) model for bending control of bendable sections (BSs) in catheters. The verification was decoupled into two steps based on the other three deformation patterns. Firstly, comparing the two-curvature (TC) model with pseudo-rigid-body (PRB), constant curvature (CC), and Euler spiral (ES) models to simulate planar bending and elongation, the results showed a more accurate shape representation. Then, five distinct catheters were employed to test the clamping universality of the module and tip positioning precision of the TC-PJ model which took torsion and shear strain into consideration. The root-mean-square error (RMSE) and the standard deviation (SD) of tip position and direction were analysed. Results indicated the module's suitability for clamping these catheters, with the large guide sheath exhibiting minimal position RMSE (SD) of around 0.10 (0.051) mm and 0.049 (2.15) degrees, while the puncture catheter demonstrated the highest position and direction RMSE (SD) extending to about 1.16 (0.53) mm and 0.70 (31.33) degrees, primarily attributed to the coupling of two sequential bendable components. Overall, the proposed actuation module and kinematic model showed the ability of universal manipulation and an average tip position and direction RMSE of 0.65 mm and 0.23 degrees in free space.

Ultrasound imaging is widely valued for its safety, non-invasiveness, and real-time capabilities but is often limited by operator variability, affecting image quality and reproducibility. Robot-assisted ultrasound may provide a solution by delivering more consistent, precise, and faster scans, potentially reducing human error and healthcare costs. Effective force control is crucial in robotic ultrasound scanning to ensure consistent image quality and patient safety. However, existing robotic ultrasound systems rely heavily on expensive commercial force sensors or the integrated sensors of commercial robotic arms, limiting their accessibility. To address these challenges, we developed a cost-effective, lightweight, 3D-printed force sensor and a hybrid position–force control strategy tailored for robotic ultrasound scanning. The system integrates patient-to-robot registration, automated scanning path planning, and multi-sensor data fusion, allowing the robot to autonomously locate the patient, target the region of interest, and maintain optimal contact force during scanning. Validation was conducted using an ultrasound-compatible abdominal aortic aneurysm (AAA) phantom created from patient CT data and healthy volunteer testing. For the volunteer testing, during a 1-min scan, 65% of the forces were within the good image range. Both volunteers reported no discomfort or pain during the whole procedure. These results demonstrate the potential of the system to provide safe, precise, and autonomous robotic ultrasound imaging in real-world conditions.

Accurate clip positioning (including position, direction, and orientation) in transcatheter mitral edge-to-edge repair (M-TEER) is challenging due to the complexity of manipulating tendon-driven concentric catheters under imaging guidance. Existing methods are limited to either task-space position/shape control or image-space joint control. This study presents a compact eight-DoF robot for controlling the PASCAL device, achieving closed-loop pose control in image space. Building on a prior variable curvature model, we develop a kinematic model that accounts for coupling between catheter handles and compensates for tip length variation. A prior sheath shape model is also integrated to support safer navigation in confined anatomy during clip adjustment. To achieve precise image-space pose control, we design a novel framework featuring a mapping strategy for independent control of clip position, direction, and orientation relative to registered imaging views, along with a Jacobian-based PID controller. Simulation results demonstrate effective independent control, with only direction adjustments exhibiting minor coupling with orientation (maximum deviation: 2.69$^{\circ }$). Experiments show that closed-loop control effectively mitigates catheter misalignment and rubber deformation, achieving average positional and angular RMSEs to 0.52 mm and 0.61$^{\circ }$. This robot provides precise, image-space pose control, which is expected to assist with the challenge of accurate clip positioning in M-TEER.

Objective: This study aimed to develop and evaluate a 3-degree-of-freedom (DoF) robotic system for the safe delivery of cardiac sheaths through challenging anatomical structures, including the fossa ovalis and pathways with tight curves. Methods: The robot and its kinematic model were built on a previously proposed single-DoF actuation module and bending model. A sheath delivery strategy (SDS) was developed, combining two control methods: tip position control to approach an optimal entry point and point-constrained control to maintain consistent navigation through this point, minimizing tissue contact. Technical performance was evaluated through trajectory-following and point-crossing tests, followed by feasibility experiments in a simulated scenario. Trials were conducted by three cardiologists using a validated phantom model under fluoroscopic guidance, comparing SDS with joint control (JC) and manual control (MC). Results: Average root mean square errors were 2.10 mm for tip position control and 1.86 mm for point-constrained control. SDS outperformed MC with significantly shorter trajectory lengths and lower root mean square jerk. Compared to JC, SDS reduced sheath-induced movements (an indirect measure of force) and increased retraction success rates at the fossa ovalis. Conclusion: The proposed robotic system reduced tissue wall contact compared to JC and provided smoother, more controlled operations than MC, ensuring safer and more effective delivery through confined pathways. Significance: This work contributes to advancing robotic-assisted cardiac sheath delivery, providing a reliable and safer method for navigating challenging anatomical structures.

Objective: This study aimed to develop and evaluate the SeptalPro system, a novel robotic platform designed to enhance the precision, safety, and efficiency of transseptal puncture (TSP) procedures by integrating real-time remote control and force sensing. Methods: The SeptalPro system was assessed using an anthropomorphic phantom in a simulated clinical environment. Four experienced cardiologists and one cardiology trainee participated in the study, performing manual and robot-assisted TSP procedures. The system's performance was evaluated using trajectory and motion smoothness metrics, as well as user feedback on the system's usability in a clinical environment. Results: The robot-assisted approach demonstrated superior spatial control compared to the manual approach, with significantly shorter path lengths and reduced spatial dispersion for experienced operators. The SeptalPro system also achieved smoother and more efficient tool motions, as indicated by reduced mean motion jerk. User feedback indicated high satisfaction with the system's usability and potential clinical benefits. Conclusion: SeptalPro represents a significant advancement in TSP, offering a promising solution to the challenges associated with the conventional manual approach. The robotic system demonstrated superior performance in terms of spatial control and motion smoothness compared to the manual approach. Significance: This work establishes the first comprehensive framework for evaluating robotic TSP systems through integration of high-precision force sensing, clinically-validated performance metrics, and structured assessment protocols, providing essential foundations towards clinical translation of robotic assistance in TSP procedures.

It is conventionally assumed that all wireless devices will fol- low some prescribed routing protocols without any deviation. However, the scarce resources in wireless devices raise a concern about this assumption. Most often, the owners of wireless devices will try to manipulate the proto- cols for its own benefit, instead of faithfully following the protocols. There- fore, some new protocols intended for selfish and rational wireless devices need to be designed. In this paper, we specifically study the multicast in selfish and rational wireless ad hoc networks. By assuming that each wireless node has a pri- vate cost of forwarding data for other nodes, we give an efficient method to construct a multicast tree, namely VMST, whose cost is 5-approximation of the optimum multicast tree cost for homogeneous wireless networks mod- elled by unit disk graph. Based on VMST, we design a truthful payment scheme that pays minimum for any relay node among all truthful payment schemes based on VMST. We also conduct extensive experiments to study the practical performances of proposed protocol. I. I NTRODUCTION Wireless networks have received significant attentions over past few years due to its potential applications in various situ- ations such as battlefield, emergency relief and environmental monitoring, etc. Unlike wired networks and cellular networks, which have fixed infrastructures, wireless ad hoc networks en- joy a more flexible composition. A wireless ad hoc network is a collection of radio devices (transceivers) located in a geo- graphic region. Each node is equipped with an omni-directional antenna and has limited transmission power. One of the dis- tinctive features of wireless networks is that the signal sent out by each wireless device can be received by all nodes within its transmission range, i.e., it can use a broadcasting-like manner to distribute the message to all neighboring nodes. In this paper, we consider a wireless ad hoc network G = (V;E) consisting of a set V of n nodes distributed in a two-dimensional plane, and an edge uv 2 E if u and v can receive signal from each other directly. When all nodes have the same maximum trans- mission range, by a proper scaling, the wireless networks are modelled by unit disk graphs in the literature: an edge uv exits iff kuvk • 1. In multi-hop wireless networks, a communication session is established either through a single-hop radio transmission if the communication parties are close enough (within the transmis- sion range of each other), or through relaying by intermedi- ate devices . Many existing routing protocols for wireless ad hoc networks assume that each individual wireless node (pos- sibly owned by individual selfish users) will follow prescribed routing protocols without deviation - except, perhaps, for the faulty or malicious ones However, some users may deviate from this, or even modify the behavior of routing protocols for self- interested reasons: a user may refuse to relay the messages for