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Robotic systems for laparoscopic minimally invasive surgery (MIS) always end up with highly sophisticated mechanisms and control schemes – making it a long and hard development process with a steep price. This paper aims to propose and realize a new, efficient and convenient strategy for building effective control systems for surgical and even other complex robotic systems.

A novel method that takes advantage of the modularization concept by integrating two middleware technologies (robot operating system and robotic technology middleware) into a common architecture based on the strengths of both was designed and developed.

Tests of the developed control system showed very low time-delay between the master and slave sides; good movement representation on the slave manipulator; and high positional and operational accuracy. Moreover, the new development strategy trial came with much higher efficiency and lower costs.

This method results in a modularized and distributed control system that is amenable to collaboratively develop; convenient to modify and update; componentized and easy to extend; mutually independent among subsystems; and practicable to be running and communicating across multiple operating systems. However, experiments show that surgical training and updates of the robotic system are still required to achieve better proficiency for completing complex minimally invasive surgical operations with the proposed and developed system.

This research proposed and developed a novel modularization design method and a novel architecture for building a distributed teleoperation control system for laparoscopic MIS.

This paper seeks to examine the inter‐organisational processes used to control international master franchise agreements from operational, relational and evolutionary perspectives.

The research is undertaken through a qualitative, in‐depth case study in the international hotel industry. The case comprises an international master franchise agreement between a large US‐based hotel franchisor and its European master franchisee.

The study identifies the inter‐related nature of operational and relational control processes and how these evolve over the life of a master franchise agreement. It reveals how the perceptions of franchise members serve to enhance or inhibit the development of relational norms and how these, in turn, impact on the predominant type of control and the specific inter‐organisational processes employed.

The research is based on a single in‐depth case study within one industrial context and the universality of the findings may therefore be limited.

The paper offers insights to managers of international master franchise agreements on the interaction between members' perceptions, relational norms developed and the inter‐organisational processes used to control the agreement. It also reveals how the use of contractual controls can inhibit the development of relational norms and negatively impact on relationships between franchisors and master franchisees. The findings presented may have relevance to managers of other types of international alliance agreements.

By drawing on both the alliance and franchise literature and employing a qualitative approach, the study helps to close a gap in the current international franchise literature through the identification of specific inter‐organisational processes for control within international master franchise agreements, how these evolve in respect of relational norms and how these are underpinned by perceptions of franchisor and franchisee members.

The purpose of this paper is to propose a novel event-triggered aperiodic intermittent sliding-mode control (ETAI-SMC) algorithm for master–slave bilateral teleoperation robotic systems to further save communication resources while maintaining synchronization precision.

By using the Lyapunov theory, a new event-triggered aperiodic intermittent sliding-mode controller is designed to synchronize master–slave robots in a discontinuous method. Unlike traditional periodic time-triggered continuous control strategy, a new ETAI condition is discussed for less communication pressure. Then, the exponential reaching law is adopted to accelerate sliding-mode variables convergence, which has a significant effect on synchronization performance. In addition, the authors use quantizers to make their algorithm have obvious progress in saving communication resources.

The proposed control algorithm performance is validated by an experiment developed on a practical bilateral teleoperation system with two PHANToM Omni robotic devices. As a result, the synchronization error is limited within a small range and the control frequency is evidently reduced. Compared with a conventional control algorithm, the experimental results illustrate that the proposed control algorithm is more sensitive to system states changes and it can further save communication resources while guaranteeing the system synchronization accuracy, which is more practical for real bilateral teleoperation robotic systems.

A novel ETAI-SMC for bilateral teleoperation robotic systems is proposed to find a balance between reducing the control frequency and synchronization control precision. Combining the traditional sliding-mode control algorithm with the periodic intermittent control strategy and the event-triggered control strategy has produced obvious effect on our control performance. The proposed ETAI-SMC algorithm helps the controller be more sensitive to system states changes, which makes it possible to achieve precise control with lower control frequency. Moreover, we design an environment contact force feedback algorithm for operators to improve the perception of the slave robot working environment. In addition, quantizers and the exponential convergence law are adopted to help the proposed algorithm perform better in saving communication resources and improving synchronization precision.

The paper refers to a pair of conjugate systems (master and slave systems) associated by the condition that the evolution of the first is function on its current state and on a future state of the second system, while the evolution of the second system depends on its current state and on a past state of the first system also. The purpose of this paper is to solve particular cases of differential systems of equations which express the behaviour of conjugate systems, in order to see what kind of symmetry or harmony is established in the common evolution of the two systems.

Becoming with the Dubois' definition of conjugate retardation and anticipation variables and his mixed advanced‐retarded differential equations, the paper considers some cases: first case when information about future and past is kept constant, without and with an impulse from the side of the master system, then when information about future and respective past is a variable.

In the case with variable information about future and past, and for a constant shift time, there are found exponential solutions; it has been ascertained that the two trajectories present a symmetry expressed by their proportionality all the time. A definition of symmetry by anticipation and retardation is given. It is also found that a system with uniform linear development cannot be in a symmetry by anticipation and retardation with any other system.

In the paper, the practical implications are linked by the relationship between man and his environment and how to consider the data delivered by forecast.

The calculus and its results, the notion of symmetry by anticipation and retardation, examples and conclusions, all are original contributions.

This paper aims to describe bridge transported servo‐manipulator (BTSM) system, which was developed to overcome the limited workspace of the conventional mechanical master‐slave manipulators in a hot cell.

The BTSM system consists of four components: a transporter with a telescoping tubeset, a slave manipulator, a master manipulator, and a remote control system. The slave manipulator is able to move horizontally, transversely, and vertically by using the transporter.

The performance test of the BTSM system has been carried out in terms of basic functions such as force threshold, bilateral control and force reflection characteristic.

With respect to design characteristic, the BTSM system has the novel features in that the individual motor modules or the slave manipulator can be repaired in a fully remote manner in case of catastrophic failure. Also, a 3D viewing camera facilitates remote tasks giving human operators realistic environmental information.

This paper aims to use the adaptive computed torque control (ACTC) method to eliminate the kinematic and dynamic uncertainties of master and slave robots and for the control of the system in the presence of forces originating from human and environment interaction.

In case of uncertainties in the robot parameters that are utilized in teleoperation studies and when the environment where interactions take place is not known and when there is a time delay, very serious problems take place in system performance. An adaptation rule was created to update uncertain parameters. In addition to this, disturbance observer was designed for slave robot. Lyapunov function was used to analyze the system’s position tracking and stability. A visual interface was designed to ensure that the movements of the master robot provided a visual feedback to the user.

In this study, a visual interface was created, and position and velocity control was achieved utilizing teleoperation; the system’s position tracking and stability were analyzed using the Lyapunov method; a simulation was applied in a real-time environment, and the performance results were analyzed.

This study consisted of both simulation and real-time studies. The teleoperation system, which was created in a laboratory environment, consisted of six-degree-of-freedom (DOF) master robots, six-DOF industrial robots and six-DOF virtual robots.

This study aims to describe and analyze an innovative mechanism of teacher-led, system-wide professional learning that has been widely adopted since the beginning of the twenty-first century in China – the Master Teacher Studio (MTS).

This paper drew from policy documents, published Chinese literature relating to MTSs and personal fieldwork experience in Shanghai, Guangdong and Zhejiang province.

The article first outlines the context framing the system change, including its policy background and evolution, and then the MTS's purpose, formative process and structure. It finally examines major teacher learning activities and the leadership roles of the MTS hosts (leaders).

This study contributed to the knowledge base of system teacher leaders and how they lead cross-school leading.

The MTS initiative described in this article shows the power of central system leadership to spread and embed effective teacher learning practices at schools.

This article provides implications for understanding and practicing teacher system leadership to support teacher professional learning in different societies.

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.

This study aims to represent a novel closed-form solutions method based on the product of the exponential model to solve the inverse kinematics of a robotic manipulator. In addition, this method is applied to master–slave control of the minimally invasive surgical (MIS) robot.

For MIS robotic inverse kinematics, the closed-form solutions based on the product of the exponential model of manipulators are divided into the RRR and RRT subproblems. Geometric and algebraic constraints are used as preconditions to solve two subproblems. In addition, several important coordinate systems are established on the surgical robot and master–slave mapping strategies are illustrated in detail. Finally, the MIS robot can realize master–slave control by combining closed-form solutions and master–slave mapping strategy.

The simulation of the instrument manipulator based on the RRR and RRT subproblems is executed to verify the correctness of the proposed closed-form solutions. The fact that the accuracy of the closed-form solutions is better than that of the compensation method is validated by the contrastive linear trajectory experiment, and the average and the maximum tracking errors are 0.1388 mm and 0.3047 mm, respectively. In the animal experiment, the average and maximum tracking error of the left instrument manipulator are 0.2192 mm and 0.4987 mm, whereas the average and maximum tracking error of the right instrument manipulator are 0.1885 mm and 0.6933 mm. The successful completion of the animal experiment comprehensively demonstrated the feasibility and reliability of the master–slave control strategy based on the novel closed-form solutions.

The proposed closed-form solutions are error-free in theory. The master–slave control strategy is not affected by calculation error when the closed-form solutions are used in the surgical robot. And the accuracy and reliability of the master–slave control strategy are greatly improved.

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.