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As the demand for human–robot collaboration in manufacturing applications grows, the necessity for collision detection functions in robots becomes increasingly paramount for safety. Hence, this paper aims to improve the existing method to achieve efficient, accurate and sensitive robot collision detection.

The external torque is estimated by momentum observers based on the robot dynamics model. Because the state of the joints is more accessible to distinguish under the action of the suppression operator proposed in this paper, the mutated external torque caused by joint reversal can be accurately attenuated. Finally, time series analysis (TSA) methods can continuously generate dynamic thresholds based on external torques.

Compared with the collision detection method based only on TSA, the invalid time of the proposed method is less during joint reversal. Although the soft-collision detection accuracy of this method is lower than that of the symmetric threshold method, it is superior in terms of detection delay and has a higher hard-collision detection accuracy.

Owing to the mutated external torque caused by joint reversal, which seriously affects the stability of time series models, the collision detection method based only on TSA cannot detect continuously. The consequences are disastrous if the robot collides with people or the environment during joint reversal. After multiple experimental verifications, the proposed method still exhibits detection capabilities during joint reversal and can implement real-time collision detection. Therefore, it is suitable for various engineering applications.

The purpose of this paper is to investigate the tribological effects of laser surface texturing (LST) and residual stress on functional surfaces.

Three different surface textures (circular dimple, elliptical dimple and groove) with two different textured area ratios (10 and 20 per cent) are designed and fabricated by a Picosecond Nd YAG Laser machine. The friction and wear performance of textured specimens is tested using a UMT-2 friction and wear testing machine in mixed lubrication.

Test results show that elliptical dimples exhibit the best performance in wear resistance, circular dimples in friction reduction and grooves in stabilization of friction. The surfaces with larger textured area density exhibit better performance in both friction reduction and wear resistance. The improved performance of LST is the coupled effect of surface texture and residual stress.

The findings of this study may provide guidance for optimal design of functional surface textures in reciprocating sliding contacts under mixed or hydrodynamic lubrication, which can be used in automotive and other industrial applications.

This study aims to propose a new decision-making method by integrating case-based decision theory and the Dempster–Shafer theory of evidence.

The study developed the entire computational procedures for the proposed method and used a numerical example to illustrate its method.

The results show that not only the own experiences of the decision-maker but also the opinions of other persons contribute to the selection. Case-based decision theory provides a fundamental technique for the decision-making procedure, and the Dempster–Shafer theory of evidence offers support to deal with the different sources of decision information.

In case-based decision theory, the utility is a subjective concept, which cannot be measured easily in numbers. Thus, future research should seek a new method to replace the utility. In addition, how to assess the importance of different persons’ experiences and opinions is an important component of this method.

The contributions of the paper are mainly reflected in three aspects. The first is to expand the traditional concept of “case” of case-based decision theory to multiple sources of cases, which include not only the decision-maker’s own experiences but also other persons’ opinions. The second is to provide a decision-making framework by integrating case-based decision theory and the Dempster–Shafer theory of evidence. The third is to develop the entire computational procedures for the proposed method.

Although brand alliance has become quite ubiquitous in the marketplace and attracted considerable interest amongst researchers, little research has investigated its effects on the brand equity of partners. The purpose of this paper is to demonstrate why and how brand alliance affects the brand equity of the partners in an alliance.

The hypotheses were tested by analysing the data of 260 participants in China, which were collected from an experiment.

This research draws five conclusions: the brand equity of a pre-alliance partner has a positive effect on brand alliance evaluation; product fit and brand fit amongst partners also have a positive effect on brand alliance evaluation; alliance brand evaluation has a positive impact on the brand equity of a post-alliance brand; the brand equity of a pre-alliance partner exerts a positive effect on the brand equity of a post-alliance partner; and the spillover effect of brand alliance for a weak brand is stronger than that of a strong brand in an asymmetrical brand alliance.

This research introduces brand equity into the field of brand alliance. From the perspective of consumer perception, the authors measure brand equity and provide insights for a company to effectively enhance brand equity through brand alliance. The authors explore ways to increase the brand equity of partners through brand alliance. Additionally, the authors discuss the spillover effects of the brand equity of partners in symmetric and asymmetric brand alliances.

E-commerce content platforms are a typical type of multi-sided platform that combines transactions with social media platforms. To solve the managerial dilemma of balancing the tension between control and autonomy of influencers' output performance, this study aims to investigate how exercising output controls through performance rewards and performance punishments impact the quantity and quality of influencers' content generation.

Choosing JD WeChat Shopping Circle as the research context and leveraging the introduction of a double commission subsidy policy and a removal policy as quasi-natural experiments, this study applied the difference-in-differences (DID) method to empirically test hypotheses.

Performance rewards incentivize influencers to generate high-quality content, but such incentivizing effects attenuate over time. Performance punishment drives influencers to generate expected pieces of high-quality content, and such safeguarding effects accentuate over time.

This study proposes output controls as an important form of governance mechanism in multi-sided platforms and substantiates how rewards and punishments as two facets of incentives affect complementors' behaviors. In addition, by distinguishing performance-contingent rewards from completion-contingent rewards, this study helps resolve the mixed findings on the effects of monetary rewards in the user-generated content (UGC) literature.

Regarding the assembly of the fuselage panel, this paper aims to illustrate a design of pre-assembly tooling of the fuselage panel for the automatic drilling riveting machine. This new prototype of pre-assembly tooling can be used for different types and sizes of fuselage panels. Also, apply to the automated drilling and riveting machine of the fuselage panels.

Based on the different structures of the fuselage panel, the position of the preassembly tooling components, location of the clamp and position of the fuselage panel are determined. After that, the overall structure of the preassembly tooling is designed, including the movable frame and the cardboard. The cardboard positioning module and the clamping module formulate a detailed design scheme of preassembly tooling for the fuselage panel. The structure of the pre-assembled tooling is optimized by static analysis. The result of the overall design is optimized by using MATLAB and CATIA-V5 software, and the results meet the condition of the design requirements.

The traditional assembly process of the fuselage is to install the fuselage panel on the preassembly tooling for positioning the hole and then install it on the automated drilling and riveting tooling for secondary tooling. Secondary tooling can consume assembly errors of the fuselage panel. The new prototype of flexible tooling design for the fuselage panel not only avoids the secondary tooling error of the fuselage panel but also meets the preassembly of different types of fuselage panels.

The further development of the flexible tooling design of the fuselage panel is to reduce the error of sliding tooling due to friction of the sliding components. Because if the assembly cycle is increased, the sliding parts will lose material due to corrosion. As a result, the repeated friction force is the root cause of the positioning error of sliding parts. Therefore, it is necessary to engage less corrosive material. Also, the lubricant may be used to reduce the corrosion in minimizing the positioning error of the sliding tool components. In addition, it is important to calculate the number of assembly cycles for efficient fuselage panel assembly.

According to the structure and assembly process characteristics of the fuselage panel, the fuselage panel preassembly tooling can optimize the assembly process of the fuselage panel and have certain practical application values.