Inner ear disorders' treatment remains challenging due to anatomical barriers. Robotic assistance seems to be a promising approach to enhance inner ear treatments and, more particularly, lead to effective targeted drug delivery into the human cochlea. In this paper we present a combination of a micro -macro system that was designed and realized in order to efficiently control the navigation of magnetic nanoparticles in an open-loop scheme throughout the cochlea, considering that the magnetic particles cannot be located in real time. In order to respect the anatomical constraints, we established the characteristics that the new platform must present then proceeded to the design of the latter. The developed system is composed of a magnetic actuator that aims to guide nanoparticles into the cochlea. Mounted on a robotic manipulator, it ensures its positioning around the patient's head. The magnetic device integrates four parallelepiped-rectangle permanent magnets. Their arrangement in space, position and orientation, allows the creation of an area of convergence of magnetic forces where nanoparticles can be pushed/pulled to. To ensure the reachability of the desired orientations and positions, a 3 DOF robot based on a Remote Centre of Motion (RCM) mechanism was developed. It features three concurrent rotational joints that generate a spherical workspace around the head. The control of the latter is based on kinematic models. A prototype of this platform was realized to validate the actuation process. Both magnetic actuator and robotic manipulator were realized using an additive manufacturing approach. We also designed a virtual human head with a life-size cochlea inside. A laser was mounted on the end effector to track the positioning of the actuator. This permitted to experimentally prove the capacity of the robotic system to reach the desired positions and orientations in accordance with the medical needs.

Path planning with obstacle avoidance has been a major challenge in robotic manipulators which are composed of multiple links especially in the case of complex-shaped obstacles. This paper proposes an improved collision-free path planning algorithm based on the Artificial Potential Field (APF) method to obtain a collision-free path from initial to a desired position and orientation. Firstly, the robot is modelled by the Denavit-Hartenberg DH parameter method. Secondly, the artificial attractive and repulsive force field equations are derived in the case of both spherical and hollow cylindrical obstacles. Then, a poly-articulated cylindrical model for the robot is used for collision detection between all its links and the obstacle. Finally, a virtual torque is generated based on the forces affecting the robot links to produce a suitable motion to approach the final target without collision with the obstacle. The algorithm is evaluated by building a simulation platform using MATLAB R2020b and Robotic Toolbox. Various simulations on the UR5 robot show that the proposed algorithm can plan a free-collision path in the 6D operational space. The simulations also show that the algorithm has a low computational cost, so it can be used for real-time applications.

Physical Human-Robot Interaction (PHRI) emphasize on human safety. In literature, two techniques were presented to improving this critical factor concerning moving devices; the first solution is purely mechanical, while the second one is based on the control. In this paper, we describe a new approach combining the two previous solutions. Our proposed paper explores a control scheme involving the use of a virtual component with an adjustable stiffness supposed to be placed between the motor shaft and the robot link. This scheme proposes a Variable Impedance Actuator (VIA) robot control methodology based on the integration of a virtual component, reflecting the behaviour of a real intrinsic Series Elastic Actuator (SEA). This novel method is potentially beneficial in reducing injuries in human/robot interaction by combining a mechanical operating principle and a control approach in order to reduce the collision forces in collaborative applications. This proposed approach was simulated and validated using a UR3 robot model, showing great capacities in reducing collision's peak forces. This paper begins with particular attention to the robot dynamics, then the articulation flexibility and force estimation have been tackled and finally ending the control architecture.

Background: During a Robot-Assisted Minimally Invasive Surgery (RA-MIS), a robot inserts a surgical tool into the patient's body through a surgical device placed at the incision position, known as the trocar. A kinematic constraint, known as Remote Center of Motion (RCM) constraint, is then generated since the tool axis must always pass through the trocar position while the tool-tip executes the surgical task. When a serial manipulator is used, the RCM constraint must be guaranteed by the control system. In this paper, we provide a generalized framework for the dynamic control of redundant manipulators used for RA-MIS. Moreover, we consider the event of desired or unexpected collisions between the robot's body and its environment, e.g. medical staff or operating room equipments. Methods: In order to guarantee the accomplishment of the surgical task in the event of collisions, we propose a joint compliance strategy, by exploiting the Jacobian null-space. The proposed control framework deals simultaneously with the surgical tool-tip trajectory, the RCM constraint and collisions in the robot's body. Results: Simulations were conducted to validate the effectiveness of the proposed formulation, using the dynamic model of a Kuka LBR 7 iiwa R800 robot arm. Results showed that the distance between the tool axis and the trocar position never increases more than 0.5 mm, even in case of collisions. Conclusions: The results showed the capacity of the proposed framework to simultaneously comply the three tasks: the tool-tip trajectory, the RCM constraint and joint compliance in case of collisions in the robot's body, always respecting the priority order between the tasks. (C) 2018 AGBM. Published by Elsevier Masson SAS. All rights reserved.

This paper deals on the design method applied to create a new useful robot for a lighting operating room. We present the specifications for this particular medical application, the proposed kinematic solutions as well as the topological and dimensional syntheses performed to choice the optimal solution. The work presented in this paper was conducted with a closely industrial collaboration, and a patent application of the chosen kinematic solution has been filed.

This paper deals with the design process adapted to medical robots. The large diversity of kinematic architectures that can be encountered in medical robotics leads us to seek a robust method dedicated to tool-guidance medical robot design. First, we detail a proposed design process adapted especially for handling the inherent needs in tool-guidance in medical robotics. This proposed method ties together the phases of the design process with their respective tools. We describe the spectrum of medical robots and particularly the variety of kinematic architectures used. Each phase of the design process is detailed through application examples in the domains of tele-echography and minimally invasive surgery, which exhibit a number of commonalities. The use of tools for accomplishing the various steps of the design process is detailed, with emphasis on medical gesture analysis. This is followed by topological and dimensional synthesis. This study illustrates how the type of medical robot can impose specific requirements and a particular approach in the design process. We expect through this paper to bring a significant contribution to the design of medical tool-guidance robots and to facilitate their integration in the clinical environment. The main contribution of this work is to propose a design process method for robotic medical tool-guidance manipulators.

SUMMARY This paper introduces the design and the optimization of a probe holder robot for tele-echography applications. To define its kinematic architecture, an approach based on motion capture of an expert's gestures during ultrasound examinations was proposed. The medical gestures analyzed consisted of ultrasound probe movements and were used to characterize the kinematic specifications of the proposed manipulator. The selected architecture was a Spherical Parallel Mechanism (SPM) with 3 degrees of freedom (DoF) and its optimal synthesis was performed using real-coded Genetic Algorithms (GA). The optimization criteria and constraints were established thanks to the collaboration of medical experts and were successively formulated and solved using mono-objective and multi-objective functions.

Introduction Reducing treatment duration in proton therapy is one of the key factor to increase the number of patient treated per day. To overcome this issue, we have developed novels haptic manual guidance control implemented on the patient positioning robot (Orion PT) to be used during the pre-positioning phase by the paramedical assistant. These manual control modes allow the paramedical assistant to be close to the patient while reducing the time for the pre-positioning setup. The four manual control modes of the robot are compared with a generic reach-and-point trajectory. Methods The main objective of this article is to compare intuitiveness of the four following manual guidance modes on the proton therapy robot already presented in [1] : - TeachPendant remote sensor with one button per Cartesian axis (with a total of 6). This is the reference control mode used in actual radio/proton therapy treatment room. - U bar haptic device located under the couch top and mounted on Force/Torque sensor to follow paramedical assistant intention in measuring applied force. This control mode was previously presented in [2] . - Couch top comanipulation mode. Paramedical assistant is able to move the couch top directly in applying force upon it. A F/T sensor located between couch top and robot end-effector measure operator intentions and move the couch top accordingly. The benefits of the haptic guidance compared to the previous one is the ability for the paramedical assistant to manipulate the robot directly from the couch top from any location around it, increasing intuitiveness. - 3D haptic joystick with translations as well as rotations placed on the couch top. The robot move as the same way as the 3D joystick does. A comparison between those haptic control modes will be done using a reference trajectory and the following criterion will be used to assess the intuitiveness of the proposed methods: - Movement duration to reach target. - Mean error between real and reference trajectory. - Learning curve. Results By now, the fourth haptic devices can be used with the robot and have been successfully tested. Several quantitative tests show intuitiveness improvement with U-bar haptic device compared to traditional control with teachPendant. Some qualitative tests will be carry out to measure the benefit of the three manual haptic control of the robot previously described. Conclusions This paper shows three novels haptic device to manually control a proton therapy robot during pre-positioning phase performed by paramedical assistant. Qualitative tests shows benefit of one of the proposed methods and quantitative tests will be executed soon.

In this paper, two kinematic structures with optimized spherical wrist modules are proposed for the practice of tele-echography through a new slave holder robot for a remote ultrasound diagnostic application. The medical gestures, performed during an ultrasound examination, are analyzed using two different techniques. The results are used in the definition of the robot kinematic structure specifications. The proposed medical robot is formed by two modules, a spherical displacement orientation module and a translation module, to control the interaction force between the probe and the patient. Multicriteria optimization is proposed and is applied to two spherical structures: one serial and one parallel. Workspace size and kinematic performance, in addition to the index of compactness of the manipulator, are considered in the optimization. The efficiency of the optimized kinematic structures across their workspace is studied and compared to determine which one is more adapted to the tele-echography application.

The objective of this article is to present the dimensional synthesis of serial and parallel spherical wrists, an important step in the design process of medical robots. This step is carried out to obtain optimal dimensions of tool-guidance medical robots. With this goal, we have first studied the specifications of two robots with different medical applications: one for tele-echography examination and one for minimally invasive surgery. Then, we have established that the medical needs expressed by the doctors were very different but the specifications in robotic terms have a lot of common points (kinematics, workspace, bulkiness). For both applications studied, robots need a mobility of three rotations around a fixed point (probe contact point on the patient's skin or trocar incision). So, a spherical wrist architecture is adapted to their needs. An important constraint related to medical applications is that the robot must be compact in order to not obstruct or collide with its environment (medical personnel or patient). We perform dimensional synthesis allowing determination of dimensions of the mechanism for serial and parallel spherical wrists, for a tele-echography robot, and a serial wrist for a minimally invasive surgery robot. We use multicriteria optimization methods minimizing a cost function to obtain both good kinematic performance and compactness for the architecture. The difficulty/challenge of this design process, depending of the studied applications, is the choice of efficient criteria describing the performances and the constraints of the robot. The design variables must faithfully represent the specifications of the robot so that its performance can respond to the medical requirements. We show, here, the different methods used for optimizing the chosen kinematic architecture for the particular medical application. These studies lead to prototypes which are validated after medical experiments. This process of dimensional synthesis will be applied to other medical applications with different sets of specified constraints.

This paper deals with an optimization method of spherical robots applied to the domain of medical robotics. This method relies on specification of indices which describe the constraints and requirements of the particular medical application. The dimensional optimization is demonstrated with two examples of four-degree-of-freedom robots: one dedicated to ultrasound tele-echography and the other a tool for minimally invasive surgery. Each of them has been designed to accurately follow medical gestures. The method involves optimization of the kinematic structure and determination of geometric parameters which have a significant role in avoiding singularities and achieving mechanism compactness. The two examples presented illustrate the robustness of the approach using specialized indices appropriate to each specific case. The method can be used with some generality for new medical robotics applications.

This paper introduces the design of a master-slave robotized system for tele-ultrasound application. The objective of these researches is to design the slave manipulator of this system and its control device (master part). The specification process of the architecture kinematic is based on the analysis of expert's gesture during ultrasound examinations. These studies have been carried out using a motion capture system. The medical gestures were analyzed in terms of ultrasound probe attitude and used in the definition of the kinematics specifications of the proposed manipulator. The Spherical Parallel Mechanism is selected because its characteristics meet the constraint requirements. The optimal synthesis of spherical parallel manipulators is performed using a realcoded Genetic Algorithm based method. Simulations on the actuator responses of the structure allowed us the validate it. In order to control this robot, we have also designed a haptic device that provides easiness to use as well as force feedback. Its orientation control strategy is based on a use of an adaptative kalman filter which efficiency was demonstrated during experimentations.

This paper deals with processes of optimisation for the design of a four degree-of-freedom robot dedicated to remote ultrasound tele-echography. This robot is designed to track the medical gestures of a remote expert moving an ultrasound probe. The goal is to optimise the kinematic structure by fixing the geometric parameters; these have a significant role in robot configuration singularities, with respect to current medical gestures and mechanism compactness. After choosing a dedicated kinematic structure, several optimisations are presented. Then an optimal choice of geometrical parameters of a global function in relation with kinematic performance indices and compactness is proposed. This robot is soon to be used in the experimental medical phase of the Prosit project.

This paper considers the practice of a tele-echography through a new slave holder robot for a remote echographic diagnostic application. This robot is integrated in a master-slave system called 'Robotic Platform for an Interactive Tele-echographic System' (PROSIT ANR French national project).The proposed approach is based on motion capture of an expert's gestures during the echography examination. The medical gestures were analyzed in terms of positions and velocities; the result has been used in the definition of the kinematics specifications of the proposed manipulator.The effective workspace size of a standard echography act, done by the medical expert, is determined through an experimental study. The evaluation of the workspace is based on the use of the Vicon Nexus motion capture system. The spherical parallel mechanism (SPM) has been selected because of its characteristics meeting the constraint requirements. In addition this architecture offers an excellent stiffness, high precision and is light weight.The design problem of a new parallel probe-holder robot according to the identified experimental workspace for the tele-echography system is presented.In this work, in order to increase the workspace volume of the manipulator, a minimal set of geometrical parameters of spherical parallel manipulators are optimized to find the maximum workspace. Seven independent design parameters have been identified.The optimal synthesis of spherical parallel manipulators is performed using a real-coded genetic algorithm (GA) based method. An optimal study of the orientation workspace is also presented.

This paper introduces the research carried out on the design of a robotized teleechography system. Such a system is composed of a master control device and a slave robotic manipulator. Our objective is to contribute to the French Agence National de Recherche (ANR) project PROSIT by designing both devices. To define the kinematic architecture, we had proposed an approach based on the analysis of the expert gesture as a first step of the design process. We have used a motion capture system to study the ultrasound examination gesture and to define the kinematic specifications for the proposed manipulator. A new kind of architecture was selected: the spherical parallel mechanism (SPM). We have chosen it because it reaches the constraint requirements. The kinematic architecture was synthesized by executing a real-coded genetic algorithm (GA). We integrated optimization criteria in the synthesis of the selected architecture. We have fixed a minimum required workspace and we have chosen to optimized the SPM in terms of dexterity and compacity. Another important part of our research was to design a haptic device to provide a very intuitive control of the tele-operated robot. We have opted for a free hand interface that integrates an active force control and feedback. An Inertial Measurement Unit (IMU) has been integrated. The data collected from the IMU that we integrated are processed by a Kalman Filter. But we have modified this predictor-estimator tool from the state of art to adapt its behavior with respect to the type of motion done by the operator. Experimentations via our motion capture system have demonstrated the accuracy of this orientation control strategy. The final step will be the experimental and clinical validation on real patients.

This paper considers the practice of a tele-echography through a new slave holder robot for a remote echographic diagnostic application. This robot is integrated in a master-slave system called ‘Robotic Platform for an Interactive Tele-echographic System’ (PROSIT ANR French national project). The proposed approach is based on motion capture of an expert’s gestures during the echography examination. The medical gestures were analyzed in terms of positions and velocities; the result has been used in the definition of the kinematics specifications of the proposed manipulator. The effective workspace size of a standard echography act, done by the medical expert, is determined through an experimental study. The evaluation of the workspace is based on the use of the Vicon Nexus motion capture system. The spherical parallel mechanism (SPM) has been selected because of its characteristics meeting the constraint requirements. In addition this architecture offers an excellent stiffness, high precision and is light weight. The design problem of a new parallel probe-holder robot according to the identified experimental workspace for the tele-echography system is presented. In this work, in order to increase the workspace volume of the manipulator, a minimal set of geometrical parameters of spherical parallel manipulators are optimized to find the maximum workspace. Seven independent design parameters have been identified. The optimal synthesis of spherical parallel manipulators is performed using a real-coded genetic algorithm (GA) based method. An optimal study of the orientation workspace is also presented.

This paper deals with the optimization of the design of a 4 degree-of-freedom robot dedicated to tele-echography. It has been designed to reproduce in real time on a patient, the medical gestures performed by a remote expert moving a fictive probe. Our goal is to optimize the kinematic structure to determine geometrical parameters, as they have a significant role in the singularities localization. In this paper, we propose optimum solutions obtained from a combination of kinematic performances and compactness indices.

This paper proposes a new ergonomic frame to describe the attitude of a robot arm and to be used for human-machine interface in telerobotic with application to telesonography. A three part psychophysical analysis enabled us to design this new system of angles exhibiting a good decorrelation among its degrees of freedom. A decorrelation improvement of up to 83% can be noticed compare to the standard 3-1-3 Euler angles. This new frame has been exploited to conceive human-machine interface with a low cost input device such as the standard IT mouse. Psychophysical results show indisputable superiority of our new system compare to the standard Euler one for orientation tracking in teleoperation conditions.

This work deals with modeling for the design of a four degree-of-freedom robot dedicated to tele-echography. It is designed to follow the medical gestures of a remote expert moving an ultrasound probe. The goal is to define the kinematic structure with optimal geometric parameters. These parameters have an important role in the robot singularities positions corresponding to the most current medical gestures. In this paper, we propose a value of these parameters validated by the kinematic indices point of view and an optimization.

In this paper, we present a control architecture based on the concept of levels. The architecture is composed of two parts called the decision part and the perception part. This organization permits to construct various configurations and is adaptable to any application. We implemented this architecture on different robotic platforms: a mobile robot, an omnidirectional robot and medical one. We focused on the generic aspect of the architecture which has the characteristic to include the tele-operation modes.