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The purpose of this paper is to design an exoskeleton robot and present a corresponding rehabilitation training method for patients in different rehabilitation stages.

This paper presents a lightweight seven-degrees-of-freedom (DOF) cable-driven exoskeleton robot that is wearable and adjustable. After decoupling joint movement caused by a cable-driven mechanism, active rehabilitation training mode and passive rehabilitation training mode are proposed to improve the effect of rehabilitation training.

Simulations and experiments have been carried out, and the results validated the feasibility of the proposed mechanism and methods by a fine rehabilitative effect with different persons.

This paper designed a 7-DOF cable-driven exoskeleton robot that is suitable for patients of different body measurements and proposed the active rehabilitation training mode and passive rehabilitation training mode based on the cable-driven exoskeleton robot.

Seeks to present a new method of trajectory planning, i.e. genetic algorithms (GA), for six‐degree‐of‐freedom (DOF) industrial robots.

Describes the effects of the GA method with the advantage of quaternion algebra and by a process of elimination selects the optimal solution.

Finds that the problem of optimization, caused by having two contrary response variables, i.e. time and distance, can only be solved by determining the importance of the variables and calculating the optimum levels of the parameters.

This study would appear to break new ground in the trajectory planning of six‐DOF industrial robots in proposing a superior alternative to conventional methods.

Compliant mechanism has been receiving a great interest in precision engineering. However, analytical methods involving their behavior analysis is still a challenge because there are unclear kinematic behaviors. Especially, design optimization for compliant mechanisms becomes an important task when the problem is more and more complex. Therefore, the purpose of this study is to design a new hybrid computational method. The hybridized method is an integration of statistics, numerical method, computational intelligence and optimization.

A tensural bistable compliant mechanism is used to clarify the efficiency of the developed method. A pseudo model of the mechanism is designed and simulations are planned to retrieve the data sets. Main contributions of design variables are analyzed by analysis of variance to initialize several new populations. Next, objective functions are transformed into the desirability, which are inputs of the fuzzy inference system (FIS). The FIS modeling is aimed to initialize a single-combined objective function (SCOF). Subsequently, adaptive neuro-fuzzy inference system is developed to modeling a relation of the main geometrical parameters and the SCOF. Finally, the SCOF is maximized by lightning attachment procedure optimization algorithm to yield a global optimality.

The results prove that the present method is better than a combination of fuzzy logic and Taguchi. The present method is also superior to other algorithms by conducting non-parameter tests. The proposed computational method is a usefully systematic method that can be applied to compliant mechanisms with complex structures and multiple-constrained optimization problems.

The novelty of this work is to make a new approach by combining statistical techniques, numerical method, computational intelligence and metaheuristic algorithm. The feasibility of the method is capable of solving a multi-objective optimization problem for compliant mechanisms with nonlinear complexity.

This paper aims to present an intuitive control system for robotic manipulators that pairs a Leap Motion, a low-cost optical tracking and gesture recognition device, with the ability to record and replay trajectories and operation to create an intuitive method of controlling and programming a robotic manipulator. This system was designed to be extensible and includes modules and methods for obstacle detection and dynamic trajectory modification for obstacle avoidance.

The presented control architecture, while portable to any robotic platform, was designed to actuate a six degree-of-freedom robotic manipulator of our own design. From the data collected by the Leap Motion, the manipulator was controlled by mapping the position and orientation of the human hand to values in the joint space of the robot. Additional recording and playback functionality was implemented to allow for the robot to repeat the desired tasks once the task had been demonstrated and recorded.

Experiments were conducted on our custom-built robotic manipulator by first using a simulation model to characterize and quantify the robot’s tracking of the Leap Motion generated trajectory. Tests were conducted in the Gazebo simulation software in conjunction with Robot Operating System, where results were collected by recording both the real-time input from the Leap Motion sensor, and the corresponding pose data. The results of these experiments show that the goal of accurate and real-time control of the robot was achieved and validated our methods of transcribing, recording and repeating six degree-of-freedom trajectories from the Leap Motion camera.

As robots evolve in complexity, the methods of programming them need to evolve to become more intuitive. Humans instinctively teach by demonstrating the task to a given subject, who then observes the various poses and tries to replicate the motions. This work aims to integrate the natural human teaching methods into robotics programming through an intuitive, demonstration-based programming method.

This paper aims to present a fully actuated aerial manipulator (AM) with a robust motion/force hybrid controller for conducting contact-typed inspection tasks in industrial plants.

An AM is designed based on a hexarotor with tilted rotors and a rigidly attached end effector. By tilting the rotors, the position and attitude of the AM can be controlled independently, and the AM can actively exert forces on industrial facilities through the rigidly attached end effector. A motion/force hybrid controller is proposed to perform contact-typed inspection tasks. The contact-typed inspection task is divided into the approach phase and the contact phase. In the approach phase, the AM automatically approaches the contact surface. In the contact phase, a motion/force hybrid controller is used for contact-typed inspection. Finally, a disturbance observer (DOB) is used to estimate external disturbances and used as feedforward compensation.

The proposed AM can slowly approach the contact surface without significant impact in the contact phase. It can realize constant force control in the direction normal to the contact surface in the contact phase, whereas the motion of the remaining directions can be controlled by the operator. The use of the DOB ensures the robustness of the AM in the presence of external wind disturbances.

A fully actuated AM system with a robust motion/force hybrid controller is proposed. The effectiveness of the proposed AM system for conducting contact-typed industrial inspection tasks is validated by practical experiments.

The purpose of this paper is to present the direct kinematic analysis of a heavy‐payload forging manipulator. In the grasping stage, the manipulator is equivalent to a 3‐DOF under‐actuated mechanism. In order to deal with the direct position kinematics of the under‐actuated mechanism, the analysis is performed in two steps.

The paper analyzes the direct position kinematics of the 3‐DOF under‐actuated mechanism as follows: first, the authors add a virtual constraint on the mechanism, convert it to a 2‐DOF fully actuated mechanism and calculate the direct kinematics of the constrained mechanism. Then, the constraint is applied to many different positions and the corresponding direct kinematics of the constrained mechanism are calculated, respectively. Finally, the mechanism with lower gravitational potential energy than any other constrained mechanism is chosen, and its direct position is what is needed for the 3‐DOF underactuated mechanism.

The paper provides a solution for the direct kinematic analysis of a heavy‐payload forging manipulator in the grasping stage. Furthermore, the simulation and experiment results confirm the effectiveness of the solution.

The paper proposes a methodology to deal with the direct position kinematics of the 3‐DOF under‐actuated mechanism in two steps.

The purpose of this paper is to use the redundancy of a new hybrid automatic fastening system (HAFS) for aircraft assembly in the best way.

First, the kinematic model of HAFS is divided into three sub-models, which are the upper/lower tool and parallel robot. With the geometric coordination relationship, a comprehensive kinematic model of the HAFS is built by mathematically assembling the sub-models based on the DH method. Then, a novel master-slave decoupling strategy for inverse kinematics solution is proposed. With the combination of the minimum energy consumption and the comfortable configuration, a multi-objective redundancy resolution method is developed to optimize the fastening configuration of the HAFS, which keep the HAFS away from the joint-limits and collision avoiding in the aircraft panel assembly process.

An efficient multi-objective posture optimization algorithm to use the redundancy in the best way is obtained. Simulation and an experiment are used to demonstrate the correctness of the proposed method. Moreover, the position and orientation errors of the drilling holes are within 0.222 mm and 0.356°, which are accurate enough for the automatic fastening in aircraft manufacturing.

This method has been used in the HAFS control system, and the practical results show the aircraft components can be fastened automatically through this method with high efficiency and high quality.

This paper proposes a comprehensive kinematic model and a novel decoupling strategy for inverse kinematic solution of the HAFS, which provides a reference to utilize the redundancy in the best way for a hybrid machine with redundant function.

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.

The purpose of this paper is to describe a calibration method developed to improve the absolute accuracy of a novel three degrees‐of‐freedom planar parallel robot. The robot is designed for the precise alignment of semiconductor wafers and, even though its complete workspace is slightly larger, the accuracy improvements are performed within a target workspace, in which the positions are on a disc of 170 mm in diameter and the orientations are in the range ±17°.

The calibration method makes use of a single optimization model, based on the direct kinematic calibration approach, while the experimental data are collected from two sources. The first source is a measurement arm from FARO Technologies, and the second is a Mitutoyo coordinate measurement machine (CMM). The two sets of calibration results are compared.

Simulation confirmed that the model proposed is not sensitive to measurement noise. An experimental validation on the CMM shows that the absolute accuracy inside the target workspace was improved by reducing the maximum position and orientation errors from 1.432 mm and 0.107°, respectively, to 0.044 mm and 0.009°.

This paper presents a calibration method which makes it possible to accurately identify the actual robot's base frame (base frame calibration), at the same time as identifying and compensating for geometric errors, actuator offsets, and even screw lead errors. The proposed calibration method is applied on a novel planar robot, and its absolute accuracy was found to improve to 0.044 mm.

This study considers both a single and multi‐mode viscoelastic analysis for wire‐coating flows. The numerical simulations utilise a finite element time‐stepping technique, a Taylor‐Petrov‐Galerkin/pressure‐correction scheme employing both coupled and decoupled procedures between stress and kinematic fields. An exponential Phan‐Thein/Tanner model is used to predict pressure‐drop and residual stress for this process. Rheometrical data fitting is performed for steady shear and pure extensional flows, considering both high and low density polyethylene melts. Simulations are conducted to match experimental pressure‐drop/flowrate data for a contraction flow. Then, for a complex industrial wire‐coating flow, stress and pressure drop are predicted numerically and quantified. The benefits are extolled of the use of a multi‐mode model that can incorporate a wide‐range discrete relaxation spectrum to represent flow response in complex settings. Contrast is made between LDPE and HDPE polymers, and dependency on individual relaxation modes is identified in its contribution to overall flow behaviour.