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Existing robot-assisted minimally invasive surgery (RMIS) system lacks of force feedback, and it cannot provide the surgeon with interaction forces between the surgical instruments and patient’s tissues. This paper aims to restore force sensation for the RMIS system and evaluate effect of force sensing in a master-slave manner.

This paper presents a four-DOF surgical instrument with modular joints and six-axis force sensing capability and proposes an incremental position mode master–slave control strategy based on separated position and orientation to reflect motion of the end of master manipulator to the end of surgical instrument. Ex-vivo experiments including tissue palpation and blunt dissection are conducted to verify the effect of force sensing for the surgical instrument. An experiment of trajectory tracking is carried out to test precision of the control strategy.

Results of trajectory tracking experiment show that this control strategy can precisely reflect the hand motion of the operator, and the results of the ex-vivo experiments including tissue palpation and blunt dissection illustrate that this surgical instrument can measure the six-axis interaction forces successfully for the RMIS.

This paper addresses the important role of force sensing and force feedback in RMIS, clarifies the feasibility to apply this instrument prototype in RMIS for force sensing and provides technical support of force feedback for further clinical application.

Teleoperated minimally invasive surgical robots can significantly enhance a surgeon's accuracy, dexterity and visualization. However, current commercially available systems do not include significant haptic (force and tactile) feedback to the operator. This paper describes experiments to characterize this problem, as well as several methods to provide haptic feedback in order to improve surgeon's performance. There exist a variety of sensing and control methods that enable haptic feedback, although a number of practical considerations, e.g. cost, complexity and biocompatibility, present significant challenges. The ability of teleoperated robot‐assisted surgical systems to measure and display haptic information leads to a number of additional exciting clinical and scientific opportunities, such as active operator assistance through “virtual fixtures” and the automatic acquisition of tissue properties.

This paper aims to develop a novel miniature 3-axis force sensor which can detect the interaction forces during tissue palpation in MIS (minimally invasive surgery). MIS offers many significant merits compared with traditional open surgery, the wound to the patients and the postoperative pains are alleviated and reduced dramatically. However, the inherent drawback due to lack of force feedback still exists while conducting some operation procedures. For example, tissue palpation performed easily during open surgery could not be realized in an MIS manner.

The force sensor is based on the resistive-based sensing method that utilizes strain gauges to measure the strain when the external loads are acting on the tip of the sensor. A novel flexible tripod structure with bending and compression deformations is designed to discriminate the magnitudes and directions of the three orthogonal force components. A linear characteristic matrix is derived to disclose the relationship between the sensitivity and the geometric parameters of the structure, and a straightforward geometric parameterized optimization method considering the sensitivity isotropy is proposed to provide the sensor structure with high sensitivity and adequate stiffness.

The sensor prototype can perform force measurement with sensing ranges of ± 3.0 N in axial direction and ± 1.5 N in radial direction, and the resolutions are 5 per cent and 1 per cent, respectively. It is concluded that this force sensor is compatible with MIS instruments and the ex-vivo experiment shows that the sensor can be used to perform tissue palpation during MIS procedures.

This paper is intended to address the significant role of force sensing and force feedback during MIS operations, and presents a new application of the resistive-based sensing method in MIS. A tripod structure is designed and a straightforward optimization method considering the sensitivity isotropy of the sensor is proposed to determine geometric parameters suited for the given external loads.

This paper aims to provide an insight into recent advancements and developments of robotics for Natural Orifice Transluminal Surgery (NOTES) procedures.

Following an introduction that highlights the evolution from Minimally Invasive Surgery (MIS) to NOTES in the medical field, this paper reviews the main robotics systems that have been designed and implemented for MIS and NOTES, summarising their advantages and limitations and remarking the technological challenges and the requirements that still should be addressed and fulfilled.

The state-of-the-art presented in this paper shows that the majority of the platforms created for NOTES are laboratory prototypes, and their performances are still far from being optimal. New solutions are required to solve the problems confronted by the proposed systems such as the limited number of DOFs, the limited resolution, the optimal fixation and stiffening of the instruments for enabling stable and precise operation, the effective transmission of forces to the tip tools, the improvement of the force feedback feeling and the proper visualization and spatial orientation of the surgical field. Advances in robotics can contribute significantly to the development and future implementation of the NOTES procedure.

This paper highlights the current trends and challenges ahead in robotics applied to NOTES procedure.

To measure the force applied to the tissue, the traditional endoscopic graspers might be equipped with a kind of tactile force sensor.

This paper presents the design, analysis, microfabrication and testing of a piezoelectric and capacitive endoscopic tactile sensor with four teeth. This tactile sensor, which is tooth‐like for safe grasping, comprises a Polyvinylidene Fluoride, PVDF film for high sensitivity and is silicon‐based for micromachinability. Being a hybrid sensor, employing both capacitive and piezoelectric techniques, it is possible to measure both the static and dynamic loads. Another feature, to be considered in its design, is the ability to detect pulse. The proposed sensor can be integrated with the tip of any current commercial endoscopic grasper without changing its original design. It is shown that using an array of sensor units, the position of the applied load can still be determined.

The static response of the sensor is obtained by applying a static force on the tooth and measuring the change in capacitance between the bottom electrode of the PVDF film and the electrode deposited on the surface of the etched cavity. The dynamic response of the device is determined by applying a sinusoidal force on the tooth of the sensor and measuring the output voltage from the PVDF film. The experimental results are compared with both analytical and finite element results. The sensor exhibits high sensitivity and linearity.

Capaciyive and piezoelectic are used to obtain both dynamic,pulse, and static loads. The sensor micromachined so, it can be used in various endoscopic applications.

This paper describes design, theoretical, and experimental analysis of a polyvinylidene fluoride (PVDF) tactile sensor, which could be integrated with an endoscopic grasper. The sensor exhibited high force sensitivity and linearity. Finite element analysis was employed to study the structural analysis of the tactile sensor with various load application and the results of this modelling are presented as the shear stress distribution and deformation contours. A comparison was made between the theoretical modeling and the experimental results.

The purpose of this paper is to design a model-based bilateral teleoperation method to improve the feedback force and velocity/position tracking for robotic-assisted tasks (such as palpation, etc.) under constant and/or varying time delay with environment dynamic property. Time delay existing in bilateral teleoperation easily destabilizes the system. Proper control strategies are able to make the system stable, but at the cost of compromised performance. Model-based bilateral teleoperation is designed to achieve enhanced performance of this time-delayed system, but an accurate model is required.

Viscoelastic model has been used to describe the robot tool-soft tissue interaction behavior. Kevin-Boltzmann (K-B) model is selected to model the soft tissue behavior due to its good accuracy, transient and linearity properties among several viscoelastic models. In this work, the K-B model is designed at the master side to generate a virtual environment of remote robotic tool-soft tissue interaction. In order to obtain improved performance, a self perturbing recursive least square (SPRLS) algorithm is developed to on-line update the necessary parameters of the environment with varying dynamics.

With fast and optimal on-line estimation of primary parameters of the K-B model, the reflected force of the model-based bilateral teleoperation at the master side is improved as well as the position/velocity tracking performance. This model-based design in the bilateral teleoperation avoids the stability issue caused by time delay in the communication channel since the exchanged information become position/velocity and estimated parameters of the used model. Even facing with big and varying time delay, the system keeps stably and enhanced tracking performance. Besides, the fast convergence of the SPRLS algorithm helps to track the time-varying dynamic of the environment, which satisfies the surgical applications as the soft tissue properties usually are not static.

The originality of this work lies in that an enhanced perception of bilateral teleoperation structure under constant/varying time delay that benefits robotic assisted tele-palpation (time varying environment dynamic) tasks is developed. With SPRLS algorithm to on-line estimate the main parameters of environment, the feedback perception of system can be enhanced with stable velocity/position tracking. The superior velocity/position and force tracking performance of the developed method makes it possible for future robotic-assisted tasks with long-distance communication.

This paper aims to dissect cross-border contracting practices among exporting businesses. The under-representation of exporter-importer dynamics and the superficial understanding of contracts are the motivation for this exploratory study.

The qualitative multiple case study design focuses on 18 small to medium size enterprise (SMEs) exporting from New Zealand. The analysis encompasses coding, pattern matching and explanation building. This paper uses coding to uncover themes and pattern matching/cross-case comparison to facilitate explanation building.

The paper underlines the scant use of formal international sales/distribution contracts, the lack of knowledge concerning contracting, barriers to contract formation, misgivings about the court system and litigation and the adoption of proxy contracts. This paper depicts varieties of contracting practices, namely, no formal contract, improvisational, normative, and formal contractual arrangements and underlines the context in which each approach applies.

Similar to most studies in this area, the dissection of contracting practices derives from the exporter side of the dyad. This robs the research of a holistic view of the exchange. Nonetheless, this paper contributes to a better understanding of contract formation and formalization and to the role of context in shaping the activities of exporting SMEs.

Although formal contracts are vital, they are not obligatory in all exchanges. Contracts matter more for high intensity exporters with comparatively short relationship histories, selling knowledge-intensive products in predominantly non-relational cultures. Policymakers should highlight the importance of contracts in such contexts and direct SMEs to several freely available resources on cross-border contracting.

The research casts fairness/equity and access to justice as pertinent structural disadvantages impacting the contracting practices of exporting SMEs.

According to the authors’ knowledge, this paper is among the first studies to provide an in-depth portrayal of the contracting practices of exporting SMEs, to detail the pervasiveness of non-contractual contracting practices and to depict contracting as nuanced and context-dependent.

The Teaching Excellence Framework was explicitly introduced as a mechanism to ‘enhance teaching’ in universities. This chapter suggests, however, that the highly complex ‘black box’ methodology used to calculate TEF outcomes effectively blunts its purpose as a policy lever. As a result, TEF appears to function primarily as performative policy act, merely gesturing towards a concern with social mobility. Informed by the data and metrics driven Deliverology approach to public management, I suggest the opacity of the TEF's assessment approach enables policymakers to distance themselves from and sidestep the wicked problems raised by the complicated contexts of contemporary higher education learning and teaching. At the same time, however, I argue that the very indeterminacy through which the framework achieves this sleight of hand creates a space in which engaged teaching practitioners can push through a more progressive approach to inclusive success.

This chapter sets out to examine the topic of a spatial analysis of urban crime through an analysis of David Simon’s seminal television series The Wire. By developing an analysis of the issues that are presented in the series, issues such as race, ethnicity and representation will be addressed in order to add to the understanding of these topics in relation to race and media representations. Each section will address a set of themes which are evident in The Wire. The chapter highlights the idea of race in the series and how characters are presented on screen. The research is also concerned with economic issues depicted in the series and the effect of the economy on the characters in Baltimore, the U.S. city in which The Wire was set.

The conclusion of the chapter addresses poverty class and inequality as topics and sets out to document these themes in relation to race. The third chapter also discusses the racism and discrimination that is apparent in The Wire. By contextualising the series, the book is attempting to theorise relevant issues surrounding race, gender and power through an examination of relevant literature and the development of a theoretical framework from which key issues will be addressed.