Calin Vaida

Kinematic Modeling and Workspace Generation for a New Parallel Robot Used in Minimally Invasive Surgery

Parallel robots offer higher stiffness and smaller mobile mass than serial ones, thus allowing faster and more precise manipulations that fit medical applications, especially surgery. This paper presents the kinematic modeling and a method for workspace generation for a new parallel robot used for minimally invasive surgery. Using the developed model of the parallel robot and the kinematic modeling, some numerical and simulation tests are presented.

Kinematic modelling of a 5-dof hybrid parallel robot for laparoscopic surgery*

Robotic-assisted surgery is a continuously developing field because robots have demonstrated clear benefits in operating rooms. Until now, vast majority of robots used in surgery had serial structures. This paper presents the kinematic modelling of a 5-degree of freedom hybrid parallel architecture in two slightly different variants. The kinematics of this structure is determined, and following the analysis of singularities, the best variant is chosen. The robot workspace is computed and finally the experimental model and some simulation results are presented.

Kinematic Analysis of an Innovative Medical Parallel Robot Using Study Parameters

The paper investigates the kinematic analysis of an innovative 5-DOF parallel medical robot used for brachytherapy. Robotic assisted brachytherapy involves the targeted treatment of cancerous cells delivering high dosages of radiation inside the tumor, using as guiding tool a highly accurate robotic arm. The kinematic modeling of this mechanism is addressed using algebraic constraint varieties and the Study parametrization of the Euclidean displacement group. Algebraic methods in connection with classical multi-dimensional geometry have proven to be very efficient in the computation of direct and inverse kinematics of mechanisms as well as the explanation of strange, pathological behavior. The obtained results are simulated and compared with the results obtained by the evaluation of the determinants of the A and B Jacobi matrices. This complete kinematic analysis of the robot will largely increase its safety during the medical procedure.

Application Oriented Design and Simulation of an Innovative Parallel Robot for Brachytherapy

The paper presents the design and simulation of a new 5-DOF parallel robot named PARA-BRACHYROB used for brachytherapy. Brachytherapy (BT) is an advanced cancer treatment technique, where radioactive seeds are delivered directly in the tumor without damaging the proximal healthy tissues. Due to the tremendous therapeutic potential of brachytherapy, many researches are encouraged to provide solutions for enhanced placement of BT devices inside the patient body, thus further developing brachytherapy robotic systems. Therefore the paper presents an innovative CT-Scan compatible robotic device for this application. The PARA-BRACHYROB system consists of a parallel robot with five degrees of freedom (DOF) for needle positioning and orientation up to the insertion point in the patient body and a 1-DOF mechanism for the needle insertion. The kinematic models of PARA-BRACHYROB are presented and validated through a multi-body simulation including a short description of the numerical and simulation results for the developed model.Copyright

A CT-Scan Compatible Robotic Device for Needle Placement in Medical Applications

Several medical applications require devices capable of placing different substances inside the human body. Due to the nature of the task it is desirable to perform these actions with visual feedback, whereas the most viable solution, especially for deep target points, is computer tomography (CT). The paper presents an innovative device, which can be fitted inside the CT gantry, and has decoupled motions to ensure maximum accuracy during the needle placement. It will be shown that for needle placement tasks 5 degrees of freedom (DOF) are sufficient to achieve the task. The geometric and kinematic model of the robot will be presented. The workspace and precision mapping are computed. Some simulation results will show the robot capabilities as well as its placement in the CT scan environment.

A Parallel Reconfigurable Robot with Six Degrees of Freedom

Shorter development times, wide variety of products and manufacturing costs optimization lead towards the development of a new type of robots that are more flexible and adaptable to all these changes. The idea of reconfiguration is thus born, many studies being focused on enlarging and improving this concept. Reconfigurable robotic systems are those that can change their geometry, their mobility degree and be default, their workspace and their applicability. This paper presents a 6 degrees of freedom (DOF) reconfigurable robot, entitled RECROB, its kinematics and possible reconfigurations with different DOFs. Based on the analysis of structure two possible configurations are identified, one of them being modeled and simulated. The paper ends with the reachable workspace representation, conclusions and applicability of such a robot.

On the Kinematics of an Innovative Parallel Robot for Brachytherapy

The chapter presents the kinematics of a new parallel robot for brachytherapy. Brachytherapy (BT) is an innovative technique called also internal radiation, which enables the physician to deliver higher doses of radiation to very-specific areas of the body. Nowadays, BT usage is limited by the insufficient accuracy of the radioactive seeds placement devices. Thus, the authors propose an innovative modular parallel structure which overcomes these limitations, enabling the high accurate positioning of the BT needles in any parts of the patient’s body. The kinematics of the new 5-DOF parallel robot is presented. The dextrous workspace of the robot is computed. Some specific advantages of this structure and the conclusions are presented in the end.

A Complete Analysis of Singularities of a Parallel Medical Robot

This paper analyzes the singular poses of a 5-DOF parallel robot used for brachytherapy. In compliance with the latest safety protocols and requirements [3] the paper presents a new mathematical model using algebraic constraints and the Study parameterization of the Euclidian displacement group. Using algebraic methods combined with multidimension geometry proved to be efficient in the calculation of the kinematics of mechanisms and in the explanations of their behavior. The results obtained using this algebraic method were analyzed with respect to the data obtained from the experimental model of the robot by comparing theoretical computation results with the actual behavior of the robot. The analysis of the kinematics using these methods allows a complete description of working modes, singularities and robot behavior enabling a safe control throughout the medical task.

Design of Dual-Arm Exoskeleton for Mirrored Upper Limb Rehabilitation

The paper addresses the upper limb rehabilitation for post-stroke patients. A dual-arm exoskeleton for the elbow and wrist flexion-extension is proposed. The added benefit of this robotic system is given by its portability and its ability to perform mirrored exercises using the motions provided by the unimpaired limb. The dual-arm exoskeleton addresses patients in the chronic phase after the stroke and even the patients in the post-acute phase allowing them to do rehabilitation exercises themselves.

RAISE - An Innovative Parallel Robotic System for Lower Limb Rehabilitation

Robotic rehabilitation is a developing field of research which could become a necessity in the next decades due to the natural shifting of the population age. The aim of the paper is to present an innovative robotic device for the rehabilitation of the lower limb of patients in the acute post stroke phase. The parallel robot has a modular construction enabling the mobility of each major joint: hip, knee and ankle. Furthermore, the robotic system kinematics is presented and the singularities are derived, to validate the proposed system for its intended medical task, considering the upper limb motion requirements for the rehabilitation exercises.