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This paper aims to introduce a new design concept for robotic manipulator driven by the special two degrees of freedom (DOF) joints. Joint as a basic but essential component of the robotic manipulator is analysed emphatically.

The proposed robotic manipulator consists of several two-DOF joints and a rotary joint. Each of the two-DOF joints consists of a cylinder pairs driven by two DC motors and a universal joint (U-joint). Both kinematics of the robotic manipulator and the two-DOF joint are analysed. The influence to output ability of the joint in terms of the scale effect of the inclined plane is analysed in ADAMS simulation software. The contrast between the general and the proposed two-DOF joint is also studied. Finally, a physical prototype of the two-DOF joint is developed for experiments.

The kinematic analysis indicates that the joint can achieve omnidirectional deflection motion at a range of ±50° and the robotic manipulator can reach a similar workspace in comparison to the general robotic manipulator. Based on the kinematic analysis, two special motion modes are proposed to endow the two-DOF joint with better motion capabilities. The contrast simulation results between the general and the proposed two-DOF joints suggest that the proposed joint can perform better in the output ability. The experimental results verify the kinematic analysis and motion ability of the proposed two-DOF joint.

A new design concept of a robotic manipulator has been presented and verified. The complete kinematic analysis of a special two-DOF joint and a seven-DOF robotic manipulator have been resolved and verified. Compared with the general two-DOF joint, the proposed two-DOF joint can perform better in output ability.

There is explosive gas in many disaster environments. The conventional search and rescue robots are not allowed to work in these environments, since they may cause explosion. The purpose of this paper is to describe the design and development of the serpentine omnitread robot HITSR‐I for working in these areas.

HITSR‐I consists of four segments, and each segment is equipped with crawlers in the four directions. It can be operated even under the situation of sideslip without any recovering actions. There are pressed CO₂ containers and the pressurized control system inside the robot, and the shells of the robot are a fully sealed up structure. They can maintain the inside pressure higher than the outside. The robot can release the communication relay node to extend the communicating area, so it can search a large area even amid rubble.

HITSR‐I was developed with the capability of climbing over 400 mm high obstacles. The maximum travel distance was 315 m. The pressurized system could enable the robot to work in Zones 1 and 2.

Design and development of a serpentine robot which can work in hazardous areas containing explosive gas. It can travel for a long distance in ruins by releasing the communication relay nodes.

Surgical robotics can be divided into two groups: specialized and versatile systems. Versatile systems can be used in different surgical applications, control architectures and operating room set‐ups, but often still based on the adaptation of industrial robots. Space consumption, safety and adequacy of industrial robots in the unstructured and crowded environment of an operating room and in close human robot interaction are at least questionable. The purpose of this paper is to describe the DLR MIRO, a new versatile lightweight robot for surgical applications.

The design approach of the DLR MIRO robot focuses on compact, slim and lightweight design to assist the surgeon directly at the operating table without interference. Significantly reduced accelerated masses (total weight 10 kg) enhance the safety of the system during close interaction with patient and user. Additionally, MIRO integrates torque‐sensing capabilities to enable close interaction with human beings in unstructured environments.

A payload of 30 N, optimized kinematics and workspace for surgery enable a broad range of possible applications. Offering position, torque and impedance control on Cartesian and joint level, the robot can be integrated easily into telepresence (e.g. endoscopic surgery), autonomous or soft robotics applications, with one or multiple arms.

This paper considers lightweight and compact design as important design issues in robotic assistance systems for surgery.

This paper presents a concept for a micro‐assembly station and shows different possibilities for increasing the positioning accuracy. The main part of the station consists of a spatial parallel structure with three translational degrees of freedom. An additional rotational axis is integrated into the working platform. This structure is constructed with low friction joints, which are nearly free of backlash. The construction of these high precision joints is presented and the characteristics of the robot such as workspace and resolution are discussed. After this an approach for increasing the accuracy of parallel robots by integrating flexure hinges into the structure is described.

Describes the design, construction, and performance of the OmniTread serpentine robot. Provides a review of other designs in this new area of mobile robotics. Presents innovative and unique mechanical and control solutions.

A theoretical analysis of key aspects of the mechanical design and their implications on the performance of the robot is presented. Extensive experimentation and testing helped optimize choices of materials for the critical components: tracks and pneumatic bellows. Performance was evaluated by an independent third party: the Southwest Research Institute.

It was found that pneumatic bellows are optimal joint actuators for serpentine robots. They can provide both strength and compliance, depending on the task, at minimal volume and weight.

The described prototype is tethered to external sources of electrical and pneumatic power. A smaller and fully self‐contained version of the OmniTread is currently under development.

A fully functional OmniTread serpentine robot will provide unprecedented mobility on rough terrain, such as the rubble of a collapsed building. The ability to climb over high obstacles and span large gaps, while still fitting through small openings suggests use of this robot in urban search and rescue, industrial inspection, and military reconnaissance tasks.

The OmniTread serpentine robot incorporates multiple original features, which resulted in three recent patents. Most notably are the Integrated pneumatic joint actuator with proportional position and stiffness control system and the “Tracks all Around” design. These features provide dramatic performance improvements in serpentine robots.

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 paper presents a method to elaborate the selections of these parameters to achieve stable grasps. The performance of a prosthetic hand is mainly determined by its mechanical design. However, the effects of the geometric parameters of the hand configuration and the object sizes on the grasp stability are unknown.

First, the thumb functions of human hands are analyzed based on the anatomical model, and the configuration characteristics of the thumbs for typical prosthetic hands are summarized. Then a method of optimizing the thumb configuration is proposed by measuring the kinematic transmission performance of robotics. On the basis of the thumb configuration analysis, a design method of the prosthetic hand configuration is proposed based on form closure theory. The discriminant function of form closure is used to analyze and determine the hand configuration parameters.

An application of this method – the newly developed HIT V prosthetic hand – elaborates the optimization of the thumb configuration and the hand configuration, where the relation between the key hand configuration parameters and the discriminant function on condition of satisfying form closure, sustained by analytical equations and graphs, is revealed and visualized. An experimental verification shows that it is an effective method to design the prosthetic hand configuration available for grasping typical objects in our daily life.

The paper shows how to easily determine the geometric dimensions of the palm, phalanges and hand configuration, so that the desired range of object sizes can be obtained.

The paper describes co‐robotic devices, aiming at accomplishing surgical operations by remote overseeing and manipulation. The concept design of a modular layout is presented, assuring body penetration by curved and twisted paths, with minimal impact. The fixture develops as an articulated snake‐like forearm, carrying a wrist and the pertinent effectors; scalpels, scissors, sewing rigs, cameras, etc. The fixture is a good example of a micro electro mechanical system, with force‐actuation and shape‐control being intrinsic properties. Different options are studied and the related basic operational characteristics are summarised and compared. The jointed forearm might include one to six blocks. Specifically, task‐oriented end‐effectors are considered, e.g. a self‐operating sewing rig, able to operate with a single thread. The robot co‐operation will drastically modify surgery practice, giving freedom from anthropocentric bounds; the paper introduces such opportunities, with comments on typical control strategies and hints on actual performance, inferred by testing on virtual reality and digital mock‐ups.

This study aims to propose a novel lightweight tendon-driven musculoskeletal arm (LTDM-arm) robot with a flexible series–parallel mixed skeletal joint structure and modularized artificial muscle system (MAMS). The proposed LTDM-arm exhibits human-like flexibility, safety and operational accuracy. In addition, to improve the safety and stability of the LTDM-arm, a control method is proposed to solve local artificial muscle overload accidents.

The proposed LTDM-arm comprises seven degrees of freedom skeletons, 15 MAMSs and various sensor systems (joint sensing, muscle tension sensing, visual sensing, etc.). It retains the morphology of a human skeleton (humerus, ulna and radius) and a simplified muscle configuration. This study proposes an input saturation control with full-state constraints to reduce local artificial muscle overload accidents caused by redundant muscle tension calculations.

3D circular trajectory experiments were conducted to verify the stability of the control method and the flexibility of the LTDM-arm. The results showed that the average error of the muscle length was approximately 0.35 mm (0.38%), which indicates that the proposed control scheme can make the output follow the target trajectory while ensuring constraint satisfaction.

The human arm is capable of performing compliant operations rapidly, flexibly and robustly in unstructured environments. Existing musculoskeletal arm robots lack simulations of the full morphology of the human arm and are insufficient in dexterity. However, the flexibility and safety features of the proposed LTDM-arm were consistent with that of the human arm. Therefore, this study offers a new approach for investigating the advantages of the musculoskeletal system and the concepts of muscle control.

This paper aims to present a new friction-stir-weld robot for large-scale complex surface structures, which has high stiffness and good flexibility.

The robot system is designed according to manufacturability of large aluminum products in aeronautic and astronautic area. The kinematic model of the robot is established, and a welding trajectory planning method is also developed and verified by experiments.

Experimental results show that the robot system can meet the requirements of friction stir welding (FSW) for large-scale complex surface structures.

Compared with other heavy robotic arm and machine tool welding devices, this robot has better working quality and capability, which can greatly improve the manufacturability for large-scale complex surface structures.

The friction-stir-weld robot system is a novel solution for welding large-scale complex surface structures. Its major advantages are the high stiffness, good flexibility and high precision of the robot body, which can meet the requirements of FSW. Besides, a welding trajectory planning method based on iterative closest point (ICP) algorithm is used for welding trajectory.