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Human-like musculoskeletal robots can fulfill flexible movement and manipulation with the help of multi joints and actuators. However, in general, sophisticated structures, accurate sensors and well-designed control are all necessary for a musculoskeletal robot to achieve high-precision movement. How to realize the reliable and accurate movement of the robot under the condition of limited sensing and control accuracy is still a bottleneck problem. This paper aims to improve the movement performance of musculoskeletal system by bio-inspired method.

Inspired by two kinds of natural constraints, the convergent force field found in neuroscience and attractive region in the environment found in information science, the authors proposed a structure transforming optimization algorithm for constructing constraint force field in musculoskeletal robots. Due to the characteristics of rigid-flexible coupling and variable structures, a constraint force field can be constructed in the task space of the musculoskeletal robot by optimizing the arrangement of muscles.

With the help of the constraint force field, the robot can complete precise and robust movement with constant control signals, which brings in the possibility to reduce the requirement of sensing feedback during the motion control of the robot. Experiments are conducted on a musculoskeletal model to evaluate the performance of the proposed method in movement accuracy, noise robustness and structure sensitivity.

A novel concept, constraint force field, is proposed to realize high-precision movements of musculoskeletal robots. It provides a new theoretical basis for improving the performance of robotic manipulation such as assembly and grasping under the condition that the accuracy of control and sensory are limited.

Compared with the robotic manipulation in structured environment, high performance assembly of complex parts in extreme special environment is facing great challenges because of the uncertainty in the environment, and the decline of the control accuracy of the robot and the sensor accuracy. The assembly and construction of the space station is a typical case. An important step in the construction of the space station is the module positioning and docking with the auxiliary of the space manipulator. The operation of the manipulator is faced with many problems, such as low sensing information accuracy, large end position deviation and the requirement of weak impact in the docking process. The purpose of this paper is to design a docking method at the strategy level to effectively solve the problems that may be faced in the docking process.

Inspired by the research of robotic high-precision compliant assembly, this paper introduces the concept of Attractive Region in Environment (ARIE) into the space manipulator–assisted module docking. The contact configuration space of the docking mechanism and the existence of ARIE are systematically analyzed. The docking strategy based on ARIE framework is proposed, in which the impedance control is used to ensure the weak impact during the docking process.

For the androgynous peripheral spacecraft docking mechanism, a large range of attractive region exists in the high-dimensional contact configuration space. The docking strategy based on ARIE framework can be designed according to the geometric characteristics of the constraint region and the structural characteristics of the docking mechanism. The virtual models and the simulation environment are established, and the effectiveness of the proposed method is preliminarily verified.

Based on the research results of robotic precision compliant manipulation, in this paper, the theory of ARIE is first systematically applied to the analysis of spacecraft docking problem and the design of docking scheme. The effectiveness of the proposed docking method is preliminarily verified for the requirements of large position tolerance and weak impact. The research results will provide theoretical support and technical reference for the assembly and construction of space station and other space manipulator operations.

The paper aims to propose a method to build environmental constraint region online in complex-shaped peg-in-hole assembly tasks.

Compared with conventional way which using computer-aided design (CAD) models of assembly parts to construct the environmental constraint region offline, the paper provides an online approach that consists of three aspects: modeling assembly parts through visual recognition, decomposing complex shapes into multiple primitive convex shapes and a numerical algorithm to simulate the peg-in-hole insertion contact. Besides, a contrast experiment is performed to validate the feasibility and effectiveness of the method.

The experiment result indicates that online construction takes less time than the offline way under the same task conditions. Furthermore, due to the CAD models of the parts are not required to be known, the method proposed in the paper has a broader application in most assembly scenarios.

With the improvement of customization and complexity of manufactured parts, the assembly of complex-shaped parts has drawn greater attention of many researchers. The assembly methods based on attractive region in environment (ARIE) have shown great performance to achieve high-precision manipulation with low-precision systems. The construction of environmental constraint region serves as an essential part of ARIE-based theory, directly affect the formulation and application of assembly strategies.

This study aims to investigate the influence of the gas-flow field distribution and design on the parts quality of 316L stainless steel and the vapor–spatter behavior.

Based on the hot-wire wind speed test method, the exact value of the gas velocity at different locations was accurately measured to establish the effect on the porosity and the mechanical properties of the parts. The influence of the placement of single or dual blow screens on the performance of the parts quality was also studied. Through scanning electron microscope and energy dispersive spectrometer, high-speed photography and other methods, the influence mechanism was explained.

It was found that too high or too low gas velocity both play a negative role, for 316L stainless steel, the range of 1.3–2.0 m/s is a suitable gas field velocity during the multilaser powder bed fusion process. And printing quality using dual blow screens is better than single.

The optimization of gas field design and optimal gas velocity (1.3–2.0 m/s) applied during laser melting can improve the quality of ML-PBF of 316L stainless steel.

This study showed the influence of the gas field on the spatter–vapor in the process during ML-PBF, and the unfavorable gas field led to the formation of pores and unmelted powders.

The purpose of this paper is to solve the tracking problem for free-floating space manipulators (FFSMs) in task space with parameter uncertainties and external disturbance.

In this paper, the novel cerebellar model articulation controller (CMAC) is designed with the feedback controller. More precisely, the parameter uncertainties in the FFSM are considered for achieving the robustness.

By using the dynamically equivalent model, the CMAC can be designed and trained with the desired performance, such that the prescribed trajectory can be followed accordingly. The simulation results are presented for illustrating the validity of the derived results.

Based on the designed CMAC, the tracking error would be approaching zero by choosing appropriate quantization level in CMAC and the corresponding learning rules can be tuned online.

The purpose of this paper is to achieve stable grasping and dexterous in-hand manipulation, the control of the multi-fingered robotic hand is a difficult problem as the hand has many degrees of freedom with various grasp configurations.

To achieve this goal, a novel object-level impedance control framework with optimized grasp force and grasp quality is proposed for multi-fingered robotic hand grasping and in-hand manipulation. The minimal grasp force optimization aims to achieve stable grasping satisfying friction cone constraint while keeping appropriate contact forces without damage to the object. With the optimized grasp quality function, optimal grasp quality can be obtained by dynamically sliding on the object from initial grasp configuration to final grasp configuration. By the proposed controller, the in-hand manipulation of the grasped object can be achieved with compliance to the environment force. The control performance of the closed-loop robotic system is guaranteed by appropriately choosing the design parameters as proved by a Lyapunove function.

Simulations are conducted to validate the efficiency and performance of the proposed controller with a three-fingered robotic hand.

This paper presents a method for robotic optimal grasping and in-hand manipulation with a compliant controller. It may inspire other related researchers and has great potential for practical usage in a widespread of robot applications.

What distinguishes digital transformation from other traditional IT transformations is its involvement of the entire organization, rather than merely the IT department. Thus, instead of taking a perspective that is confined to the IT department, this paper studies the ambidextrous nature of digital transformation (DT) from the standpoint of the whole firm. The authors define DT ambidexterity as the capability to utilize digital technology to simultaneously improve the efficiency of existing businesses (DT exploitation) and to promote business growth (DT exploration).

Using annual reports of Chinese firms as a mining material, this paper deploys text mining and word frequency analysis to develop a data set of digital transformation to construct DT exploitation, DT exploration and DT ambidexterity, so that the authors can examine and compare their impact on business performance.

This study's statistics show that observations in this research sample mainly manifest DT ambidexterity and DT exploitation, while DT exploration makes up the smallest proportion. The authors find that DT exploitation, DT exploration, and DT ambidexterity have positive, yet heterogeneous effects on business performance.

This study expands the existing literature of IT-related ambidexterity by examining the ambidextrous nature of DT from the angle of company-wide strategy instead of the perspective from IT-department and expands the extant literature of digital transformation by examining the heterogeneous effects of its different components on business performance. The authors also add to the digital strategizing literature by showing that different business strategy goals can be attained through different stages of DT.

This study expands the existing literature of IT-related ambidexterity by examining the ambidexterity nature of DT from the angle of company-wide strategy instead of the perspective from IT department and expands the extant literature of digital transformation by examining the heterogeneous effects of its different components on business performance. The authors also add to the digital strategizing literature by showing that different business strategy goals can be attained through different stages of DT.

Supernumerary robotic limbs (SRLs) are a new type of wearable robot, which improve the user’s operating and perceive the user’s environment by extra robotic limbs. There are some literature reviews about the SRLs’ key technology and development trend, but the design of SRLs has not been fully discussed and summarized. This paper aims to focus on the design of SRLs and provides a comprehensive review of the ontological structure design of SRLs.

In this paper, the related literature of SRLs is summarized and analyzed by VOSviewer. The structural features of different types of SRLs are extracted, and then discuss the design approach and characteristics of SRLs which are different from typical wearable robots.

The design concept of SRLs is different from the conventional wearable robots. SRLs have various reconfiguration and installed positions, and it will influence the safety and cooperativeness performance of SRLs.

This paper focuses on discussing the structural design of SRLs by literature review, and this review will help researchers understand the structural features of SRLs and key points of the ontological design of SRLs, which can be used as a reference for designing SRLs.

The purposes of this paper are to analyze whether digital finance can contribute to enterprises' innovation performance and to determine the mediating effect of government subsidies.

This paper empirically examines the impacts of digital finance on enterprises' innovation performance by looking at Chinese companies listed on the SME and GEM boards from 2011 to 2018 to build an econometric model to test our hypotheses. The mediating effect of government subsidies, the moderating effect of financial constraints are examined, as well as shareholding of the largest shareholders in each selected company and the asset-liability ratio.

The results show that digital finance has a significant promotional effect on firms' innovation performance and that government subsidies play a partial mediating role in digital finance's contribution to firms' innovation performance. In addition, financial constraints and the shareholding of the largest shareholders in each selected company have a negative moderating effect on the relationship between government subsidies and firms' innovation performance. On the contrary, the asset-liability ratio is found to positively affect the relationship.

There has been limited research to date on the relationship between digital finance and firms' innovation performance, particularly with regard to the extent to which digital finance can influence innovation performance and the mechanisms for doing so. Therefore, it is of great significance to examine the relationship between digital finance and enterprises' innovation performance, which can also provide guidance for both the Chinese government and enterprises.

To achieve project success, an effective project risk management procedure is inevitable. The purpose of this paper is to investigate the influence of risk factors on project success in the Chinese construction industry context.

This study by way of utilizing both qualitative and quantitative methods has examined risk factors that are closely linked to project success in the Chinese construction industry.

After a thorough survey and analysis, risk factors related to designer, contractor, subcontractor, client and government are shown to affect project success to some extent.

It is suggested that the present research may be made more generalizable by a larger, more representative samples across various industries and regions of China.