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Most of the redundant dual-arm robots are singular free, dexterous and collision free compared to other robotic arms. This paper aims to analyse the workspace of redundant arms to study the manipulability. Furthermore, multi-layer perceptron (MLP) algorithm is used to determine the various joint parameters of both the upper body redundant arms. Trajectory planning of robotic arms is carried out with the help of inverse solutions obtained from the MLP algorithm.

In this paper, the kinematic equations are derived from screw theory approach and inverse kinematic solutions are determined using MLP algorithm. Levenberg–Marquardt (LM) and Bayesian regulation (BR) techniques are used as the backpropagation algorithms. The results from two backpropagation techniques are compared for determining the prediction accuracy. The inverse solutions obtained from the MLP algorithm are then used to optimize the cubic spline trajectories planned for avoiding collision between arms with the help of convex optimization technique. The dexterity of the redundant arms is analysed with the help of Cartesian workspace of arms.

Dexterity of redundant arms is analysed by studying the voids and singular spaces present inside the workspace of arms. MLP algorithms determine unique solutions with less computational effort using BR backpropagation. The inverse solutions obtained from MLP algorithm effectively optimize the cubic spline trajectory for the redundant dual arms using convex optimization technique.

Most of the MLP algorithms used for determining the inverse solutions are used with LM backpropagation technique. In this paper, BR technique is used as the backpropagation technique. BR technique converges fast with less computational time than LM method. The inverse solutions of arm joints for traversing optimized cubic spline trajectory using convex optimization technique are computed from the MLP algorithm.

The mechanization of the meat cutting companies has become essential due to the lack of skilled workers and to working conditions. This paper deals with the analysis of human gestures in order to improve the performance of a redundant robotic cell. The aim is to define optimization criteria linked to the process and the human gesture analysis to improve the cutting process with a redundant robotic cell.

This paper deals with an optimized path planning of complex tasks based on the human arm analysis. The first part details the operator's manual work. The robotized cutting strategy using bones as a guide associated with an industrial force control leads to the tasks redefinition. Thus, the analysis of the arm during the tasks is presented. With a robotic model, the authors evaluate the relevance of two criteria (kinematic and mechanical) that the operator naturally manages. These criteria are used to improve the robotized cutting process by using redundancy. Simulation work and experimentation are presented to show the enhanced performance.

The paper explains how to define optimization criteria based on human arm analysis to realize cutting operations which require force or dexterity performance. It presents a study on the criteria weighting on a robotic arm model established through human arm analysis. The optimized cutting process clearly shows improvement.

The scalability of the ham implied the definition of iterative trajectories to follow the curvature of the bone. Due to the use of an industrial force control, no online optimization can be achieved. The off-line optimization implies that the boundary of the trajectory space is technically feasible. Nevertheless, more information has to be extracted from the deboning process such as vision data in order to improve cutting quality.

This study was carried out within the framework of several national and European projects (FUI SRDViand, ANR ARMS, FP7 Echord Dexdeb) in collaboration with ADIV (Meat Institute Development Agency). The redundant robotic cell was developed and implemented at ADIV and used for feasibility studies in connection with SME/SMI French sector.

The paper deals with the cutting of soft bodies such as meat and complex human gesture analysis, which constitute an innovative challenge for the coming years in order to help or replace humans in industrial meat companies with difficult working conditions.

The purpose of this paper is to present a step‐by‐step methodology for the design of parallel kinematic machines (PKMs), from the initial stages of the conceptual definition of a new machine to an optimum design fulfilling the complete set of design requirements.

The methodology includes consideration of the kinematic, static and dynamic features required for the manipulator, which must all be assessed in complete industrial design. It is applied to a 4‐degrees‐of‐freedom (DOF) Schönflies motion generator for pick & place operations by way of example.

The authors specify the key stages of a detailed design procedure for parallel manipulators.

There are many publications on the development of specific robots and parallel manipulators based on their particular characteristics. However, it is relatively rare to find a paper on the general procedure with a step‐by‐step methodology applicable to any parallel manipulator.

This paper aims to provide tools for the complete Jacobian analysis of robotic manipulators of general topology, using a comprehensive velocity equation.

First, a modelling process is made in order to build the velocity equation using simple constraint equations: i.e. length restriction, relative motion and rigid body constraints. Then the motion space is solved, i.e. the space that spans all feasible motions of the manipulator.

The velocity equation is comprehensive, i.e. it relates all kinematic variables, not only input and output. The Jacobian related to the comprehensive velocity equation is a square dimensionless matrix. This characteristic has great importance when evaluating manipulability or closeness to singularities. Employing the motion space, any kinematic entity can be studied: i.e. velocities and accelerations of any active/passive joints, screw axis, axodes, and so on. Also a comprehensive singularity analysis can be made.

The approach presented is focused on the kinetostatic analysis of manipulators and, therefore, subjected to rigid body assumption.

The paper presents a proposal of effective codes for engineering analysis of manipulators.

This approach is based on a pure computational kinematic analysis that unifies all kinetostatic analysis for any manipulator topology (i.e. serial, parallel, hybrid manipulators, complex mechanisms, redundant‐or non‐redundant‐actuated). The characteristic Jacobian matrix is dimensionless and provides the means for a complete singularity analysis and an effective use of indicators.

The purpose of this paper is to propose a two-degrees-of-freedom wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring, in order to improve the robot’s athletic ability, load capacity and rigidity, and to ensure the coordination of multi-modal motion.

First, based on the rotation transformation matrix and closed-loop constraint equation of the parallel trunk joint mechanism, the mathematical model of its inverse position solution is constructed. Then, the Jacobian matrix of velocity and acceleration is derived by time derivative method. On this basis, the stiffness matrix of the parallel trunk joint mechanism is derived on the basis of the principle of virtual work and combined with the deformation effect of the rope driving pair and the spring elastic restraint pair. Then, the eigenvalue distribution of the stiffness matrix and the global stiffness performance index are used as the stiffness evaluation index of the mechanism. In addition, the performance index of athletic dexterity is analyzed. Finally, the distribution map of kinematic dexterity and stiffness is drawn in the workspace by numerical simulation, and the influence of the introduced spring on the stiffness distribution of the parallel trunk joint mechanism is compared and analyzed. It is concluded that the stiffness in the specific direction of the parallel trunk joint mechanism can be improved, and the stiffness distribution can be improved by adjusting the spring elastic structure parameters of the rope-driven branch chain.

Studies have shown that the wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring has a great kinematic dexterity, load-carrying capacity and stiffness performance.

The soft-mixed structure is not mature, and there are few new materials for the soft-mixed mixture; the rope and the rigid structure are driven together with a large amount of friction and hindrance factors, etc.

It ensures that the multi-motion mode hexapod mobile robot can meet the requirement of sufficient different stiffness for different motion postures through the parallel trunk joint mechanism, and it ensures that the multi-motion mode hexapod mobile robot in multi-motion mode can meet the performance requirement of global stiffness change at different pose points of different motion postures through the parallel trunk joint mechanism.

The trunk structure is a very critical mechanism for animals. Animals in the movement to achieve smooth climbing, overturning and other different postures, such as centipede, starfish, giant salamander and other multi-legged animals, not only rely on the unique leg mechanism, but also must have a unique trunk joint mechanism. Based on the cooperation of these two mechanisms, the animal can achieve a stable, flexible and flexible variety of motion characteristics. Therefore, the trunk joint mechanism has an important significance for the coordinated movement of the whole body of the multi-sport mode mobile robot (Huang Hu-lin, 2016).

In this paper, based on the idea of combining rigid parallel mechanism with wire-driven mechanism, a trunk mechanism is designed, which is composed of four spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism in series. Its spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism can make the multi-motion mode mobile robot have better load capacity, mobility and stiffness performance (Qi-zhi et al., 2018; Cong-hao et al., 2018), thus improving the environmental adaptability and reliability of the multi-motion mode mobile robot.

The purpose of this paper is to develop a portable all‐position welding robot for the welding of intersected pipes.

A complete procedure is adopted to conduct the design. The task and motion of the robot are analyzed and a mathematical description of the pose and position of the welding tool is given. Based on that, three representative types of robot are chosen in the type synthesis of mechanism. Two new indices proposed to evaluate required properties of the robot, along with the traditional dexterity index, are chosen to be the criteria in the dimension synthesis of mechanism. Through the optimization by genetic algorithm, the best robot in type and dimension is determined after comparison on their performances. Finally, the prototype is developed.

The paper finds a new robot for welding intersected pipes.

A new robot is introduced for the welding of intersected pipes. A complete design procedure is adopted to conduct the design. Two new indices are constructed for evaluating the required properties of this robot.

This study aims to introduce a multi-configuration, three-finger dexterous hand with integrated high-dimensional sensors and provides an analysis of its design, modeling and kinematics.

A mechanical design scheme of the three-finger dexterous hand with a reconfigurable palm is proposed based on the existing research on dexterous hands. The reconfigurable palm design enables the dexterous hand to achieve four grasping modes to adapt to multiple grasping tasks. To further enhance perception, two six-axis force and torque sensors are integrated into each finger. The forward and inverse kinematics equations of the dexterous hand are derived using the D-H method for kinematics modeling, thus providing a theoretical model for index analysis. The performance is evaluated using three widely applied indicators: workspace, interactivity of fingers and manipulability.

The results of kinematics analysis show that the proposed hand has excellent dexterity. Additionally, three different experiments are conducted based on the proposed hand. The performance of the dexterous hand is also verified by fingertip force, motion accuracy test, grasping and in-hand manipulation experiments based on Feix taxonomy. The results show that the dexterous hand has good grasping ability, reproducing 82% of the natural movement of the human hand in daily grasping activities and achieving in-hand manipulations such as translation and rotation.

A novel three-finger dexterous hand with multi-configuration and integrated high-dimensional sensors is proposed. It performs better than the previously designed dexterous hand in actual experiments and kinematic performance analysis.

The aim of this paper is to present new robotic structures that can be suitable for inspection, maintenance and dismantling tasks in nuclear facilities.

In the first part, two types of parallel robots capable to climb through structures are presented. The kinematics of the proposed platforms is reviewed, with emphasis on the analysis of the singularities. Next section shows the control architecture and the hardware setup of the developed system. Finally, the prototypes developed are showed and some conclusions are obtained.

The slave robot is a parallel structure with the ability to climb over structures and with a very high load capacity. The master device is a parallel device with special characteristics that makes easier the teleoperation of the parallel slave robot.

The paper presents a teleoperation system based on parallel platform with 6 degrees of freedom to overcome the classical difficulties of teleoperation in nuclear facilities.

The purpose of this paper is to provide a general approach to compute, determine, and characterize the connectivity of the end‐effector of a robotic manipulator of arbitrary architecture, in any of the postures that it can reach.

The types of motion of this link, i.e. translational, screw motions, combinations thereof, and self‐motions, are first defined and determined, simplifying the understanding of the instantaneous behaviour of the manipulator, aided by the definition of an alternative input basis.

The characterization provided by this paper simplifies the understanding of the instantaneous behaviour of the manipulator. The mobility of the end‐effector is completely characterized by the principal screws of its motion, which can be obtained from a generalized eigenproblem. In the process, alternative demonstrations of well‐known properties of the principal screws are provided.

The approach presented is focused on the kinetostatic analysis of manipulators, and therefore, subjected to rigid body assumption.

This paper proposes effective approaches for engineering analysis of robotic manipulators.

This approach is based on a pure theoretical kinematic analysis that can characterize computationally the motion that the end‐effector of an industrial robot of general morphology (i.e. serial, parallel, hybrid manipulators, complex mechanisms, redundant or non‐redundantly actuated). Also, being implemented on a general‐purpose software for the kinematic analysis of mechanisms, it provides visual information of the motion capabilities of the manipulator, highly valuable on its design stages.

To present a new special explosive ordnance disposal (EOD) robot designed to operate onboard airplanes.

The design approach adopted is multidisciplinary: mechanical and control architectures are conceived simultaneously. Modularity and lifecycle are considered. Motion and EOD tasks are controlled in tele‐operation.

A new EOD robot was designed in detail and it is ready to be built. A dynamic simulator has been written and set‐up, including a virtual reality module. The simulator is used to define the control logics. Simulation results are satisfactory. The simulator can be used as a training platform for the bomb squads.

The intent to keep the cost of the robot low conditioned the selection of the materials. Only aluminium and standard composites (like carbon fibers composites) have been used. A higher degree of freedom of the arm could increase the usability of the system; to limit the cost, the degree of freedom was limited to seven. A decision support system based on an expert system interfaced with the simulator could improve the performance of the system.

A new EOD robot will be built and commercialised soon by the industrial partner Ansaldo Ricerche.

The EOD robots available for use inside aircrafts are discussed. A new system named AirEOD is presented, including mobile platform, dexterous arm and all related design and control issues.