scholarly journals Vision-Based Suture Tensile Force Estimation in Robotic Surgery

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 110
Author(s):  
Won-Jo Jung ◽  
Kyung-Soo Kwak ◽  
Soo-Chul Lim
Keyword(s):  
Force Feedback ◽  
Short Term Memory ◽  
Tensile Force ◽  
Force Sensor ◽  
Interaction Force ◽  
Force Estimation ◽  
Training Experience ◽  
Pulling Force

Compared to laparoscopy, robotics-assisted minimally invasive surgery has the problem of an absence of force feedback, which is important to prevent a breakage of the suture. To overcome this problem, surgeons infer the suture force from their proprioception and 2D image by comparing them to the training experience. Based on this idea, a deep-learning-based method using a single image and robot position to estimate the tensile force of the sutures without a force sensor is proposed. A neural network structure with a modified Inception Resnet-V2 and Long Short Term Memory (LSTM) networks is used to estimate the suture pulling force. The feasibility of proposed network is verified using the generated DB, recording the interaction under the condition of two different artificial skins and two different situations (in vivo and in vitro) at 13 viewing angles of the images by changing the tool positions collected from the master-slave robotic system. From the evaluation conducted to show the feasibility of the interaction force estimation, the proposed learning models successfully estimated the tensile force at 10 unseen viewing angles during training.

Repetitive tensile stress to rat caudal vertebrae inducing cartilage formation in the spinal ligaments: a possible role of mechanical stress in the development of ossification of the spinal ligaments

2006 ◽  
Vol 5 (3) ◽  
pp. 234-242 ◽  
Author(s):  
Nobuaki Tsukamoto ◽  
Takeshi Maeda ◽  
Hiromasa Miura ◽  
Seiya Jingushi ◽  
Akira Hosokawa ◽  
...  
Keyword(s):  
Tensile Stress ◽  
Mechanical Stress ◽  
Tensile Force ◽  
Bone Morphogenetic Protein 2 ◽  
Woven Bone ◽  
Morphogenetic Protein ◽  
Caudal Vertebrae ◽  
Spinal Ligaments

Object Mechanical stress has been considered one of the important factors in ossification of the spinal ligaments. According to previous clinical and in vitro studies, the accumulation of tensile stress to these ligaments may be responsible for ligament ossification. To elucidate the relationship between such mechanical stress and the development of ossification of the spinal ligaments, the authors established an animal experimental model in which the in vivo response of the spinal ligaments to direct repetitive tensile loading could be observed. Methods The caudal vertebrae of adult Wistar rats were studied. After creating a novel stimulating apparatus, cyclic tensile force was loaded to rat caudal spinal ligaments at 10 N in 600 to 1800 cycles per day for up to 2 weeks. The morphological responses were then evaluated histologically and immunohistochemically. After the loadings, ectopic cartilaginous formations surrounded by proliferating round cells were observed near the insertion of the spinal ligaments. Several areas of the cartilaginous tissue were accompanied by woven bone. Bone morphogenetic protein–2 expression was clearly observed in the cytoplasm of the proliferating round cells. The histological features of the rat spinal ligaments induced by the tensile loadings resembled those of spinal ligament ossification observed in humans. Conclusions The findings obtained in the present study strongly suggest that repetitive tensile stress to the spinal ligaments is one of the important causes of ligament ossification in the spine.

In-Vivo Force Estimation of the Anterior Cruciate Ligament

2009 ◽  
Author(s):  
Ali Hosseini ◽  
Thomas J. Gill ◽  
Guoan Li
Keyword(s):  
Anterior Cruciate Ligament ◽  
Cruciate Ligament ◽  
Acl Injury ◽  
Force Estimation ◽  
Non Invasive ◽  
Injury Mechanisms ◽  
Invasive Method ◽  
Anterior Cruciate

The knowledge of in-vivo ACL forces is instrumental for understanding ACL injury mechanisms and for improving surgical ACL reconstruction techniques. Several in-vitro investigations have measured ACL forces in response to various loads applied to the knee. However, in-vivo ACL forces in response to controlled loading are still unknown. The objective of this study was to estimate the force of healthy ACL as well as the possible upper bound of ACL forces under an increasing axial tibial loading in living subjects using a non-invasive method.

Using the fringe field of a clinical MRI scanner enables robotic navigation of tethered instruments in deeper vascular regions

2019 ◽  
Vol 4 (36) ◽  
pp. eaax7342 ◽  
Author(s):  
Arash Azizi ◽  
Charles C. Tremblay ◽  
Kévin Gagné ◽  
Sylvain Martel
Keyword(s):  
Insertion Site ◽  
Superconducting Magnet ◽  
Fringe Field ◽  
Friction Forces ◽  
Human Scale ◽  
Clinical Magnetic Resonance Imaging ◽  
Pulling Force ◽  
Clinical Mri

Navigating tethered instruments through the vasculatures to reach deeper physiological locations presently inaccessible would extend the applicability of many medical interventions, including but not limited to local diagnostics, imaging, and therapies. Navigation through narrower vessels requires minimizing the diameter of the instrument, resulting in a decrease of its stiffness until steerability becomes unpractical, while pushing the instrument at the insertion site to counteract the friction forces from the vessel walls caused by the bending of the instrument. To reach beyond the limit of using a pushing force alone, we report a method relying on a complementary directional pulling force at the tip created by gradients resulting from the magnetic fringe field emanating outside a clinical magnetic resonance imaging (MRI) scanner. The pulling force resulting from gradients exceeding 2 tesla per meter in a space that supports human-scale interventions allows the use of smaller magnets, such as the deformable spring as described here, at the tip of the instrument. Directional forces are achieved by robotically positioning the patient at predetermined successive locations inside the fringe field, a method that we refer to as fringe field navigation (FFN). We show through in vitro and in vivo experiments that x-ray–guided FFN could navigate microguidewires through complex vasculatures well beyond the limit of manual procedures and existing magnetic platforms. Our approach facilitated miniaturization of the instrument by replacing the torque from a relatively weak magnetic field with a configuration designed to exploit the superconducting magnet-based directional forces available in clinical MRI rooms.

Gripping Force Feedback System for Neurosurgery

2014 ◽  
Vol 8 (1) ◽  
pp. 83-94 ◽  
Author(s):  
Yoshinori Fujihira ◽  
◽  
Takuya Hanyu ◽  
Yusuke Kanada ◽  
Takeshi Yoneyama ◽  
...  
Keyword(s):  
Force Feedback ◽  
Feedback System ◽  
Force Sensor ◽  
Thin Plates ◽  
Display Device ◽  
Kinesthetic Sense ◽  
The Difference ◽  
Pulling Force ◽  
Gripping Force ◽  
Force Sense

A force feedback manipulator system was developed for use in neurosurgery. The system consists of a multidegree of freedom manipulator with a forcedetecting gripper and a device capable of using force feedback to display kinesthetic sense. The structure, which consists of parallel thin plates in the gripper of the manipulator, enables the detection of a gripping force and a pulling force, which can be used to grip and pull tumors. In this paper, we describe ways of improving the structure of the force sensor. Throughbilateral control, the operation device is able to display the gripping force as its driving force, and the pulling force as the frictional force between the display device and the skin of the finger. We also conducted experiments to test the force sense display capabilities of the developed system. The results showed that the system can display a force and the difference between the softness of different objects that are gripped. The ability of the system to identify different objects is increased by magnifying the detected force using an appropriate scale.

A Novel Method to Measure Mitral Valve Chordal Tension

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
Zhaoming He ◽  
Christopher Jowers
Keyword(s):  
Mitral Valve ◽  
Force Sensor ◽  
New Method ◽  
Ring Size ◽  
Mitral Valves ◽  
Novel Method ◽  
Healthy Functioning ◽  
Leaflet Coaptation

Proper leaflet coaptation of the mitral valve is vital for a healthy functioning heart. Chordal tension directly affects leaflet coaptation. The C-shaped transducer used previously to measure chordal tension was too big for tension measurement of multiple chordae and their branches. A new method is needed to measure chordal tension with minimum interference with chord and leaflet motion. The method was to extrapolate longitudinal chordal tension from transverse chordal fibril force measured by inserting a small elliptical AIFP4 sensor from MicroStrain Inc. (Williston, VT) through a chord. Sensitivity of the method has been tested with the sensor implanted in chordae, and error of the method has been estimated at various sensor deviation angles. Intact porcine and ovine hearts were used to measure mitral valve strut and marginal chordal tensions at static transmitral pressures of 120mmHg and 160mmHg under an in vitro condition. The results obtained from the AIFP4 sensor were similar to the results obtained previously by C-shaped transducers in the porcine mitral valves. The sensor output errors increased with the increase in sensor deviation angle in the chord at a peak systolic tension. Strut chordal tensions of four ovine mitral valves of Edwards ring size M 28 were 0.29±0.06N at the transmitral pressure of 120mmHg. The tension of 18 porcine strut chordae of porcine mitral valves of Edwards ring size M 32 was 1.00±0.42N at the transmitral pressures of 120mmHg. The tension of 22 anterior leaflet marginal chordae from porcine mitral valves of Edwards ring size M 32 was 0.10±0.04N at the transmitral pressure of 120mmHg. A new method using an AIFP4 miniature force sensor to measure mitral valve chordal tension indirectly is successfully developed. This force sensor works well in measuring mitral valve chordal tension at an in vitro hydrostatic transmitral pressure. The size and simple fixation of the sensor make it favorable for chordal tension measurement of multiple chordae and their branches under in vitro or in vivo conditions with minimal interference with chordal geometry and dynamics.

A μ-Synthesis Based Control for Compliant Maneuvers

2006 ◽  
Vol 128 (4) ◽  
pp. 914-921
Author(s):  
Yutaka Uchimura ◽  
H. Kazerooni
Keyword(s):  
Control System ◽  
Force Feedback ◽  
Controller Design ◽  
Force Sensor ◽  
Force Estimation ◽  
Dexterous Manipulation ◽  
Human Dynamics ◽  
Physical Strength ◽  
Human Power ◽  
Central Control System

This paper deals with a system, which is subjected to very uncertain factors: human and environment. These independent uncertainties are dealt with explicitly on the framework of μ-synthesis. We also describe a controller design, which enables a robust force feedback without using a force sensor. The model of human dynamics, environments, and actuators are modeled associated with uncertainties described in the form of weighting functions. A controller is designed based on the μ-synthesis so that it maintains robust performance against uncertainties in both environment and human dynamics, which contributes to dexterous manipulation. The controller described here is implemented on the human power extender, which is worn by a human and amplifies the human’s physical strength, while the human’s intelligence remains as the central control system for manipulation. Experimental results conducted on the extender showed that the force estimation worked fine and the control system performed as desired.

Adhesion of Polycarboxylate-based Dental Cements to Enamel: An in vivo Study

1986 ◽  
Vol 65 (6) ◽  
pp. 885-887 ◽  
Author(s):  
T. Jemt ◽  
P.A. Stålblad ◽  
G. Øilo
Keyword(s):  
Bond Strength ◽  
Tensile Force ◽  
Test Method ◽  
Glass Ionomer Cements ◽  
Glass Ionomer ◽  
Adhesive Failure ◽  
Cohesive Failure ◽  
The Mean

The bond strength of two polycarboxylate and two glass ionomer cements to enamel in vivo has been measured by a tensile test method. The four cements were used to cement small stainless steel cylinders onto the facial surfaces of 11 and 21. The cylinders were removed by a tensile force applied by a handpiece containing a semi-conductor sensory unit. The results showed that all cements gave two sets of bond strength values, either a good bond corresponding to a cohesive failure, or a weak bond corresponding to an adhesive failure. The mean bond strength values were lower than those recorded in vitro, and differences among the cements were limited.

scholarly journals In Vitro Reconstitution of Dynein Force Exertion in Bulk Cytoplasm

2020 ◽  
Author(s):  
Héliciane Palenzuela ◽  
Benjamin Lacroix ◽  
Jérémy Sallé ◽  
Katsuhiko Minami ◽  
Tomohiro Shima ◽  
...  
Keyword(s):  
Viscous Medium ◽  
Hydrodynamic Interactions ◽  
Cell Cortex ◽  
Cellular Processes ◽  
In Vitro Reconstitution ◽  
Reconstituted System ◽  
Pulling Force ◽  
Glass Surfaces

SUMMARYThe forces generated by Microtubules (MTs) and their associated motors orchestrate essential cellular processes ranging from vesicular trafficking to centrosome positioning [1, 2]. To date, most studies have focused on force exertion from motors anchored on a static surface, such as the cell cortex in vivo or glass surfaces in vitro [2–4]. However, motors also transport large cargos and endomembrane networks, whose hydrodynamic interactions with the viscous cytoplasm should generate sizable forces in bulk. Such forces may contribute to MT aster centration, organization and orientation [5–14], but have yet to be evidenced and studied in a minimal reconstituted system. By developing a bulk motility assay, based on stabilized MTs and dynein-coated beads freely floating in a viscous medium away from any surface, we demonstrate that the motion of a cargo exerts a pulling force on the MT and propels it in opposite direction. Quantification of resulting MT movements for different motors, motor velocities, over a range of cargo size and medium viscosities, shows that the efficiency of this mechanism is primarily determined by cargo size and MT length. Forces exerted by cargos are additive, allowing us to recapitulate tug-of-war situations, or bi-dimensional motions of minimal asters. These data also reveal unappreciated effects of the nature of viscous crowders and hydrodynamic interactions between cargos and MTs, likely relevant to understand this mode of force exertion in living cells. This study places endomembrane transport as a significant mode of MT force exertion with far-reaching consequences for cellular organization.

δ Opioid Receptor Inverse Agonists and their In Vivo Pharmacological Effects

2020 ◽  
Vol 20 (31) ◽  
pp. 2889-2902 ◽  
Author(s):  
Shigeto Hirayama ◽  
Hideaki Fujii
Keyword(s):  
Opioid Receptor ◽  
Short Term Memory ◽  
Inverse Agonist ◽  
Pharmacological Effects ◽  
Short Term ◽  
Inverse Agonists ◽  
Δ Opioid Receptor ◽  
Receptor Inverse Agonist

The discovery of δ opioid receptor inverse agonist activity induced by ICI-174,864, which was previously reported as an δ opioid receptor antagonist, opened the door for the investigation of inverse agonism/constitutive activity of the receptors. Various peptidic or non-peptidic δ opioid receptor inverse agonists have since been developed. Compared with the reports dealing with in vitro inverse agonist activities of novel compounds or known compounds as antagonists, there have been almost no publications describing the in vivo pharmacological effects induced by a δ opioid receptor inverse agonist. After the observation of anorectic effects with the δ opioid receptor antagonism was discussed in the early 2000s, the short-term memory improving effects and antitussive effects have been very recently reported as possible pharmacological effects induced by a δ opioid receptor inverse agonist. In this review, we will survey the developed δ opioid receptor inverse agonists and summarize the possible in vivo pharmacological effects by δ opioid receptor inverse agonists. Moreover, we will discuss important issues involved in the investigation of the in vivo pharmacological effects produced by a δ opioid receptor inverse agonist.

scholarly journals Estimating Tool–Tissue Forces Using a 3-Degree-of-Freedom Robotic Surgical Tool

2016 ◽  
Vol 8 (5) ◽  
Author(s):  
Baoliang Zhao ◽  
Carl A. Nelson
Keyword(s):  
Force Feedback ◽  
Estimation Method ◽  
Interaction Force ◽  
Normal Function ◽  
Degree Of Freedom ◽  
Force Estimation ◽  
Robot Assisted ◽  
Interaction Forces ◽  
Tissue Interaction ◽  
Surgical Tool

Robot-assisted minimally invasive surgery (MIS) has gained popularity due to its high dexterity and reduced invasiveness to the patient; however, due to the loss of direct touch of the surgical site, surgeons may be prone to exert larger forces and cause tissue damage. To quantify tool–tissue interaction forces, researchers have tried to attach different kinds of sensors on the surgical tools. This sensor attachment generally makes the tools bulky and/or unduly expensive and may hinder the normal function of the tools; it is also unlikely that these sensors can survive harsh sterilization processes. This paper investigates an alternative method by estimating tool–tissue interaction forces using driving motors' current, and validates this sensorless force estimation method on a 3-degree-of-freedom (DOF) robotic surgical grasper prototype. The results show that the performance of this method is acceptable with regard to latency and accuracy. With this tool–tissue interaction force estimation method, it is possible to implement force feedback on existing robotic surgical systems without any sensors. This may allow a haptic surgical robot which is compatible with existing sterilization methods and surgical procedures, so that the surgeon can obtain tool–tissue interaction forces in real time, thereby increasing surgical efficiency and safety.

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