Existing wearable MTSs are fixed in size and cannot accommodate patients with diverse abdominal circumferences. Here we propose a wearable and reconfigurable MTS. First, we design a reconfigurable sensor array inspired by the structure of bamboo slips, allowing it to conform to the abdominal surface and accommodate individuals with different abdominal circumferences. Next, we formulate a magnetic tracking optimization problem based on the magnetic dipole model and our established kinematic model of the reconfigurable sensor array.
Our proposed system is portable, reconfigurable and adaptable to different abdominal circumferences, offering valuable technological means for diagnosing and treating gastrointestinal disorders.
In the study of minimally invasive surgical robots, a mini parallel continuum robot (PCR) has shown motion advantage after passing through a long and winding working channel. However, due to the interaction force between the elastic wires of the parallel robots during motion generation processes, the constant curvature assumption has shown modeling errors. This causes the current geometric kinematic model to become unreliable. This paper aims to solve this issue. The simulation in ANSYS is carried out, and the shape of one of the driving wires, when bending, is fitted by a two-segment polynomial curve. Then, the position of the distal wrist tip can be calculated based on the curve shape. To verify the accuracy of the proposed model, bending simulation and experiment are carried out. The accuracy of the proposed model is compared with that of the kinematic model based on constant curvature assumption. The result shows that the proposed model can get more accurate results, especially when the driving wire displacement increases.
Main contributions:
1. A two-segment polynomial curve was used to model the deformation of the parallel wrist joint. Compared with the kinematic model based on constant curvature assumption, the proposed curve has shown higher accuracy.
2. The fitting results of the chosen NiTi wire with the proposed curve were verified by finite element simulation (Fig. 3).
3. The modeling accuracy was verified when the deflection angle was 0ยฐ, 30ยฐ and 45ยฐ respectively. The experimental results show that the accuracy of this method is improved significantly than that of the constant curvature model. Especially, when the bending angle is increased, its accuracy does not decrease significantly.
Stay tuned to more of our research on parallel continuum robot!!!
Capsule endoscopes, predominantly serving diagnostic functions, provide lucid internal imagery but are devoid of surgical or therapeutic capabilities. Consequently, despite lesion detection, physicians frequently resort to traditional endoscopic or open surgical procedures for treatment, resulting in more complex, potentially risky interventions.
To surmount these limitations, this study introduces a chained flexible capsule endoscope (FCE) design concept, specifically conceived to navigate the inherent volume constraints of capsule endoscopes whilst augmenting their therapeutic functionalities. The FCEโs distinctive flexibility originates from a conventional rotating joint design and the incision pattern in the flexible material. In vitro experiments validated the passive navigation ability of the FCE in rugged intestinal tracts. Further, the FCE demonstrates consistent reptile-like peristalsis under the influence of an external magnetic field, and possesses the capability for film expansion and disintegration under high-frequency electromagnetic stimulation. These findings illuminate a promising path toward amplifying the therapeutic capacities of capsule endoscopes without necessitating a size compromise.
Author team: Sishen YUAN, Guang Li, Baijia Liang, Lailu Li, Qingzhuo Zheng, and Prof Hongliang Ren from the Chinese University of Hong Kong, Prof Shuang Song from Harbin Institute of Technology, Shenzhen, and Dr Zhen Li from Qilu Hospital of Shandong University.
For details, please check the paper at https://lnkd.in/gcq2HB9H
Helicobacter pylori, a pervasive bacterial infection associated with gastrointestinal disorders such as gastritis, peptic ulcer disease, and gastric cancer, impacts approximately 50% of the global population. The efficacy of standard clinical eradication therapies is diminishing due to the rise of antibiotic-resistant strains, necessitating alternative treatment strategies. Photodynamic therapy (PDT) emerges as a promising prospect in this context.
This study presents the development and implementation of a magnetically-guided origami robot, incorporating flexible printed circuit units for sustained and stable phototherapy of Helicobacter pylori. Each integrated unit is equipped with wireless charging capabilities, producing an optimal power output that can concurrently illuminate up to 15 LEDs at their maximum intensity. Crucially, these units can be remotely manipulated via a magnetic field, facilitating both translational and rotational movements.
We propose an open-loop manual control sequence that allows the formation of a stable, compliant triangular structure through the interaction of internal magnets. This adaptable configuration is uniquely designed to withstand the dynamic squeezing environment prevalent in real-world gastric applications. The research herein represents a significant stride in leveraging technology for innovative medical solutions, particularly in the management of antibiotic-resistant Helicobacter pylori infections.
This is a collabrative work by Sishen YUAN, Baijia Liang, Po Wa Wong, Mingjing Xu, Chi Hsuan Li and Prof Hongliang Ren from The Chinese University of Hong Kong, and Dr. Zhen Li from Qilu Hospital of Shandong University.
For details, please check the paper at https://lnkd.in/g3VGZaA3
๐ In this paper, we unveil an innovative autonomous palpation-based acquisition strategy – RASEC, designed for the tracheal region. RASEC predicts the next acquisition point interactively, maximizing expected information and minimizing palpation procedure costs. By leveraging a Gaussian Process (GP) to model tissue hardness distribution and anatomical information as a guiding input for medical robots, RASEC revolutionizes robot-assisted subtasks in tracheotomy.
๐ก We introduce a dynamic tactile sensor based on resonant frequency to measure tissue hardness at millimeter-scale precision, ensuring secure interactions. By exploring kernel fusion techniques blending Squared Exponential (SE) and Ornstein-Uhlenbeck (OU) kernels, and optimizing Bayesian search with larynx anatomical data, we enhance exploration efficiency and accuracy.
๐ฌ Our research considers new factors like tactile sensor movement and robotic base rotation in the acquisition strategy. Simulation and physical phantom experiments demonstrate a remarkable 53.1% reduction in sensor movement and 75.2% reduction in base rotation, with superior algorithmic performance metrics (average precision 0.932, average recall 0.973, average F1 score 0.952) and minimal distance errors (0.423 mm) at a high resolution of 1 mm.
๐ The results showcase RASEC’s excellence in exploration efficiency, cost-effectiveness, and incision localization accuracy in real robot-assisted tracheotomy procedures.
This collaborative work is achieved by WENCHAO YUE, Fan Bai, Jianbang Liu, and Prof Hongliang Ren from The Chinese University of Hong Kong, Prof Feng Ju from Nanjing University of Aeronautics and Astronautics, Prof Max Q.-H. Meng from Southern University of Science and Technology, and Dr. Chwee Ming Lim from Singapore General Hospital.
๐ก Soft pneumatic actuators are at the heart of soft robotics, offering reliability, safety, and flexibility. However, conventional bulky air compressors and pipes have limited their integration and lightweight design. Enter the Peltier pouch motor (PPM), a cutting-edge soft thermoelectric-based actuator that redefines possibilities in the field.
๐ The PPM introduces modular and dual-stroke capabilities through active phase transition of a low-boiling-point liquid, enabling pipeless thermo-pneumatic actuation. Its lightweight and stretchable design fosters hyper-modularity, paving the way for diverse degrees-of-freedom hybrid systems.
๐ From thermo-responsive land locomotion to submersible noise-free hovering and beyond, the PPM excels in various applications, including smart curtains control, body-temperature-driven wrist rehabilitation, and adaptive hybrid gripping. Our results showcase exceptional performance metrics, highlighting high load rates (around 400%), remarkable heat transfer efficiency (heating boost 425%, cooling boost 138%), and rapid thermal response (heating 0.57ยฐโsโ1, cooling 0.29ยฐโsโ1 at 4.5โV).
The paper is available at https://lnkd.in/gfS5fGSw
The research is the result of a remarkable collaboration between Yang Yang from CUHK and ZJU, Sam, Jiewen Lai from CUHK, Chaochao Xu from NUS, Zhiguo He and Pengcheng Jiao from ZJU, and Hongliang Ren from CUHK and NUS.
๐ Open the below article for more details!!!
There has been a growing need for soft robots operating various force-sensitive tasks due to their environmental adaptability, satisfactory controllability, and nonlinear mobility unique from rigid robots. It is of desire to further study the system instability and strongly nonlinear interaction phenomenon that are the main influence factors to the actuations of lightweight soft actuators.
Here, we present a design principle on lightweight pneumatically elastic backbone structure(PEBS) with the modular construction for soft actuators, which contains a backbone printed as one piece and a common strip balloon. We build a prototype of a lightweight (<80 g) soft actuator, which can perform bending motions with satisfactory output forces (~ 20 times self-weight).
Experiments are conducted on the bending effects generated by interactions between the hyper-elastic inner balloon and the elastic backbone. We investigated the nonlinear interaction and system instability experimentally, numerically and parametrically. To overcome them, we further derived a theoretical nonlinear model and a numerical model. Satisfactory agreements are obtained between the numerical, theoretical and experimental results. The accuracy of the numerical model is fully validated. Parametric studies are conducted on the backbone geometry and stiffness, balloon stiffness, thickness, and diameter. The accurate controllability, operation safety, modularization ability, and collaborative ability of the PEBS are validated by designing PEBS into a soft laryngoscope, a modularized PEBS library for a robotic arm, and a PEBS system that can operate remote surgery. The reported work provides a further applicability potential of soft robotics studies.
FIG. 1. Illustrative demonstration of the PEBS: (a) the detailed structure and dimensions of the PEBS, (b) the design principle that can be divided into the separation stage and the interaction stage, and (c) the design principle that can be specifically divided into the separation stage, the insufficient interaction stage, the full interaction stage, and the excessive interaction stage, based on the interaction conditions.
FIG. 2. Nonlinear interaction phenomenon analyses: (a) the free oscillation phenomenon of the backbone structure generated by the structural asymmetric stress responses to gravity, (b) the interaction performances of the backbone structure and the density plot showing the relationship between the gap numbers, pressures, and bending angles, (c) the interaction performances of the balloon and the relationships between the pressures and expansion ratios regarding the radial and axial expansion ratios, respectively, (d) relationships between the pressures and stresses regarding the backbone structure and balloon, respectively.
FIG. 3. Applications of PEBS demonstrate unique advantages of accurate controllability, operation safety, modularization ability, and collaborative ability. (a) A PEBS soft laryngoscope that can operate laryngeal diagnosis. (b) Real-time images captured by the integrated image sensor. (c) Modularized PEBS library that can be installed onto a robot arm. (d) A PEBS grasper that can operate various grasping tasks. (e) The PEBS system can be potentially applied to operate a debridement.
Developing a multi-functional magnetic-driven soft robot to carry out various medical missions remains challenging. In this work, we design a tripedal soft magnetic robot with three radial magnetized cylindric permanent magnets embedded in three soles. The motion modalities for movement include butterfly crawling (along the x and y axis), scorpion crawling, and rolling. At different frequencies, the robot exhibits different behaviors in terms of speed and trajectory under different moving modalities. The maximum velocity of the butterfly crawling and scorpion crawling motion at the frequency of 1 Hz is measured to be 5.30 mm/s and 9.06 mm/s.
For details, please check the paper at https://lnkd.in/gfbRzNYu
Our work proposes the Curriculum-based Augmented Fourier Domain Adaptation (Curri-AFDA) and proves to achieve superior adaptation, generalization, and robustness performance for medical image segmentation.
**Motivation**
Medical image segmentation is key to improving computer-assisted diagnosis and intervention autonomy. However, due to domain gaps between different medical sites, deep learning-based segmentation models frequently encounter performance degradation when deployed in a novel domain. Moreover, model robustness is also highly expected to mitigate the effects of data corruption.
**Methodology**
Considering all these demanding yet practical needs to automate medical applications and benefit healthcare, we propose the Curriculum-based Fourier Domain Adaptation (Curri-AFDA) for medical image segmentation. Specifically, we design a novel curriculum strategy to progressively transfer amplitude information in the Fourier space from the target domain to the source domain to mitigate domain gaps and incorporate the chained augmentation mixing to further improve the generalization and robustness ability.
**Performance**
Extensive experiments on two segmentation tasks with cross-domain datasets show the consistent superiority of our method regarding adaptation and generalization on multiple testing domains and robustness against synthetic corrupted data. Besides, our approach is independent of image modalities because its efficacy does not rely on modality-specific characteristics. In addition, we demonstrate the benefit of our method for image classification besides segmentation in the ablation study. Therefore, our method can potentially be applied in various medical applications and yield improved performance.
This paper is an extended version of our #ICRA2023 Surgical-VQLA. Our method can serve as an effective and reliable tool to assist in surgical education and clinical decision-making by providing more insightful analyses of surgical scenes.
โจ Key Contributions in the journal version:
– A dual calibration module is proposed to align and normalize multimodal representations.
– A contrastive training strategy with adversarial examples is employed to enhance robustness.
– Various optimization function is widely explored.
– The EndoVis-18-VQLA & EndoVis-17-VQLA datasets are further extended.
– Our proposed solution presents superior performance and robustness against real-world image corruption.
Conference Version (ICRA 2023): https://lnkd.in/gHscT3eN
Journal Version (Information Fusion): https://lnkd.in/gQNWwHmt
