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Planning and control of humanoid biped walking has been an active research topic for many years. But, there is no definite answer to the question of how to practicre‐examinedally achieve speedy and stable walking in real‐time and in a changing environment. The purpose of this paper is to re‐examine the issue of planning and controlling humanoid biped walking, then to propose two new ideas.

The first idea is to treat the supporting foot of a biped to be part of the ground. In this way, there is a foot reaction force acting at a fixed virtual joint, which can be at, or below, the ankle joint. And, a new concept is come our that is named as in‐foot ZMP in contrast to the existing concept of on‐ground ZMP. The unique benefit with this new concept of in‐foot ZMP is that the ZMP control is no longer an issue because the in‐foot ZMP can be controlled so as to to be at a fixed virtual joint during a stable walking. Such a fixed virtual joint can be called a ZMP joint.

The second idea is to focus on hip's trajectory (instead of on‐ground ZMP's trajectory) and to split a hip's dynamic response into two independent parts: one is the steady‐state response contributing to the stability of walking (or standing), and the other is the transient response contributing to the speed of walking. This idea allows us to explicitly postulate the necessary and sufficient condition for achieving leg stability as well as the necessary and sufficient condition for achieving foot stability. The paper shows that the implementation of these two new ideas help realize a unified framework for task‐guided, intention‐guided, and sensor‐guided, planning and control of humanoid biped walking.

This paper first re‐examines the issue of planning and controlling humanoid biped walking, then proposes two new ideas. The first idea is to treat the supporting foot of a biped to be part of the ground. The second idea is to focus on hip's trajectory (instead of on‐ground ZMP's trajectory) and to split a hip's dynamic response into two independent parts: one is the steady‐state response contributing to the stability of walking (or standing), and the other is the transient response contributing to the speed of walking.

Autonomous mobile manipulation depends on a lot of effort at various levels. In general, the hardware design is as important as algorithm (or software) design. In particular, the absence of certain capabilities of hardware can seriously affect the feasibility and performance of algorithms. The purpose of this paper is to present work on developing hardware capability for mobile manipulation by low‐cost humanoids (LOCH) humanoid robot.

This paper presents research work on developing the hardware support which enables vision‐guided mobile manipulation realized on top of a biped humanoid robot called LOCH. One important goal which guides the development is to achieve the hardware capability with human‐like dexterity, modularity, functionality, and appearance.

This paper discusses the detail of solutions leading to the realization of the intended hardware capability, focusing in particular on the issues related to mechanism, actuation, distributed sensing, and distributed control of humanoid head, humanoid hands and humanoid arms. Finally, the paper shows the result of the actual prototype, which can be controlled by a remote control station through wireless connection.

In designing a machine, it is common to do motor‐sizing and material selection. Since these are standard procedures, these details are omitted because readers with the training in mechanical engineering should be able to work out such details in order to select the appropriate motors and materials. Also, this paper does not delve into the description of the biped system of LOCH humanoid, because such work requires another long paper in order to reveal major details.

This paper presents the major detail of research efforts toward developing hardware capabilities for achieving autonomous mobile manipulation by LOCH humanoid robot, focusing on three important modules, namely: perception head, human‐like hands, and arms. The uniqueness of this work is twofold. First, LOCH humanoid robot's perception head has the most versatile sensing capabilities, which are fully integrated into a compact and human‐like head. Second, each of LOCH humanoid robot's hands has 14 degrees of freedom, which are realized within a mechanism which is of human‐hand size and shape. In addition, the perception head, humanoid hands and humanoid arms are seamlessly integrated together owing to the adoption of a distributed system which supports networked sensing and control through the use of both control area network bus and transmission control protocol/internet protocol internet.

This paper primarily aims to focus on a review of convolutional neural network (CNN)-based eye control systems. The performance of CNNs in big data has led to the development of eye control systems. Therefore, a review of eye control systems based on CNNs is helpful for future research.

In this paper, first, it covers the fundamentals of the eye control system as well as the fundamentals of CNNs. Second, the standard CNN model and the target detection model are summarized. The eye control system’s CNN gaze estimation approach and model are next described and summarized. Finally, the progress of the gaze estimation of the eye control system is discussed and anticipated.

The eye control system accomplishes the control effect using gaze estimation technology, which focuses on the features and information of the eyeball, eye movement and gaze, among other things. The traditional eye control system adopts pupil monitoring, pupil positioning, Hough algorithm and other methods. This study will focus on a CNN-based eye control system. First of all, the authors present the CNN model, which is effective in image identification, target detection and tracking. Furthermore, the CNN-based eye control system is separated into three categories: semantic information, monocular/binocular and full-face. Finally, three challenges linked to the development of an eye control system based on a CNN are discussed, along with possible solutions.

This research can provide theoretical and engineering basis for the eye control system platform. In addition, it also summarizes the ideas of predecessors to support the development of future research.

This paper aims to address the speed and flux tracking problem of an induction motor (IM) drive that propels an electric vehicle (EV). A new continuous control law is developed for an IM drive by using the backstepping design associated with the Robust Integral Sign of the Error (RISE) technique.

First, the rotor field-oriented IM dynamic model is derived. Then, a RISE-backstepping approach is proposed to compensate for the load torque disturbance under the assumptions that the disturbances are C² class functions with bounded time derivatives.

The numerical validation results have presented good control performances in terms of speed and flux reference tracking. It is also robust against load disturbances rejection and IM parameters variation compared to the conventional Field-Oriented Control design. Besides, the asymptotic stability and the boundedness of the closed-loop signals is guaranteed in the context of Lyapunov.

A very relevant strategy based on a conjunction of the backstepping design with the RISE technique is proposed for an IM drive. The approach remains simple and can be scaled to different applications.

The theoretical analysis indicates that the main factors of cover‐shelter properties of fabrics are cover factor of fabrics, fabric thickness, optical reflectance and absorbance of yarn. With a combination of distances and luminances, 512 experiments have been made to find out the relationship between the least distinguishable distance and reflectance coefficient.

The purpose of this paper is to analyze the dependent competing failure reliability of harmonic drive (HD) with strength failure and degradation failure.

Based on life tests and stiffness degradation experiments, Wiener process is used to establish the accelerated performance degradation model of HD. Model parameter distribution is estimated by Bayesian inference and Markov Chain Monte Carlo (MCMC) and stiffness degradation failure samples are obtained by a three-step sampling method. Combined with strength failure samples of HD, copula function is used to describe the dependence between strength failure and stiffness degradation failure.

Strength failure occurred earlier than degradation failure under high level accelerated condition; degradation failure occurred earlier than strength failure under medium- or low-level accelerated condition. Gumbel copula is the optimum copula function for dependence modeling of strength failure and stiffness degradation failure. Dependent competing failure reliability of HD is larger than independent competing failure reliability.

The reliability evaluation method of dependent competing failure of HD with strength failure and degradation failure is first proposed. Performance degradation experiments during accelerated life test (ALT), step-down ALT and life test under rated condition are conducted for Wiener process based step-down accelerated performance degradation modeling.

Expanded polystyrene (EPS) is a low‐density and cheap material, which has been widely used in commercial areas. As the demand for small‐batch, flexible and quick production increases, producing EPS products with metals moulds has become unaffordable. The purpose of this paper is to describe the development of an EPS rapid prototyping (ERP) process, with an electric heating tool.

Two new cutting strategies for the ERP process, constant angle mode and constant thickness mode, are proposed. The methods to generate tool path of those models are also discussed. In order to improve accuracy and cutting effectiveness, experiments have been carried out to investigate the thermal characteristics in the ERP process. Consequently, the relationships between the size of material removal area and process parameters are obtained. Suitable processing parameters for the ERP system are also conducted.

It is found that the ERP process can rapidly produce complex three‐dimensional parts in one‐off clamping without post‐processing procedures as in traditional rapid prototyping, such as, extra support removing, step texture finishing and distortion regulating.

The paper provides several examples to explain and illustrate the applicability and workflow of the ERP system.

The purpose of this paper is to propose a new algorithm chaotic pigeon-inspired optimization (CPIO), which can effectively improve the computing efficiency of the basic Itti’s model for saliency-based detection. The CPIO algorithm and relevant applications are aimed at air surveillance for target detection.

To compare the improvements of the performance on Itti’s model, three bio-inspired algorithms including particle swarm optimization (PSO), brain storm optimization (BSO) and CPIO are applied to optimize the weight coefficients of each feature map in the saliency computation.

According to the experimental results in optimized Itti’s model, CPIO outperforms PSO in terms of computing efficiency and is superior to BSO in terms of searching ability. Therefore, CPIO provides the best overall properties among the three algorithms.

The algorithm proposed in this paper can be extensively applied for fast, accurate and multi-target detections in aerial images.

CPIO algorithm is originally proposed, which is very promising in solving complicated optimization problems.

Intuitionistic linguistic fuzzy information (ILFI), characterized by linguistic terms and intuitionistic fuzzy sets (IFSs), can easily express the fuzzy information in the process of muticriteria decision making (MCDM) and muticriteria group decision making (MCGDM) problems. The purpose of this paper is to provide an overview of aggregation operators (AOs) and applications of ILFI.

First, some meaningful AOs for ILFI are summarized, and some extended MCDM approaches for intuitionistic uncertain linguistic variables (IULVs), such as extended TOPSIS, extended TODIM, extended VIKOR, are discussed. Then, the authors summarize and analyze the applications about the AOs of IULVs.

IULVs, characterized by linguistic terms and IFSs, can more detailed and comprehensively express the criteria values in the process of MCDM and MCGDM. Therefore, lots of researchers pay more and more attention to the MCDM or MCGDM methods with IULVs.

The authors summarize and analyze the applications about the AOs of IULVs Finally, the authors point out some possible directions for future research.

The purpose of this paper is to propose a new algorithm for linear-quadratic regulator (LQR) controller of a quadrotor with fast and stable performance, which is based on pigeon-inspired optimization (PIO).

The controller is based on LQR. The determinate parameters are optimized by PIO, which is a newly proposed swarm intelligent algorithm inspired by the characteristics of homing pigeons.

The PIO-optimized LQR controller can obtain the optimized parameters and achieve stabilization in about 3 s.

The PIO-optimized LQR controller can be easily applied to the flight formation, autonomous aerial refueling (AAR) and detection of unmanned aerial vehicles, especially applied to (AAR) in this paper.

This research applies PIO to optimize the tuning parameters of LQR, which can considerably improve the fast and stabilizing performance of attitude control. The simulation results show the effectiveness of the proposed algorithm.