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This paper aims to propose a real-time evolutionary multi-objective semi-analytical inverse kinematics (IK) algorithm (EMSA-IK) for solving the multi-objective IK of redundant manipulators.

Within EMSA-IK, the parameterization method is applied to reduce the number of optimization variables of the evolutionary algorithm and calculate semi-analytical solutions that meet high target pose accuracy. The original evolutionary algorithm is improved with the proposed adaptive search sub-space strategy so that the improved evolutionary algorithm can be used to efficiently perform global search within the parametric joint space to obtain the global optimal parametric joint angles that satisfy multi-objective constraints.

Ablation experiments show the effectiveness of the improved strategy used for evolutionary algorithms. Comparative experiments on different manipulators demonstrate the advantages of EMSA-IK in terms of generalizability and balancing multiple objectives, for example, motion continuity, joint limits and obstacle avoidance. Real-world experiments further validate the effectiveness of the proposed algorithm for real-time application.

The semi-analytical IK solution that simultaneously satisfies high target pose accuracy and multi-objective constraints can be obtained in real time. Compared to existing semi-analytical IK algorithms, the proposed algorithm achieves obstacle avoidance for the first time. The proposed algorithm demonstrates superior generalizability, applicable to not only redundant manipulators with revolute joints but also those with prismatic joints.

People are starting to doubt business recovery in office market after global financial crisis in 2008. And most institutional and individual portfolios are undiversified in real estate : incurring enormous transaction costs than other financial products. Especially office market has more risks than other real estate market for high transaction costs and many related industries. Although this stuff can lead to increase the risk of investment in office market, nor are there markets that would allow individuals and institutions to hedge their risks. The establishment of office price index future and option markets is likely to hedge away large risk in office market, and provides lowering transaction costs for trading in real estate. We estimate Office Price Index using S&P/Case-Shiller repeat sale estimator which is proposed by Robert. J. Shiller in 1991. The estimator is a sort of Feasible Generalized Two Stage Least Squares, which compute Value weighted Arithmetic Price Index.

The purpose of the study was to develop a performance flat-plate solar collector that would be used as a solar drier for fruit fig (Ficus carica L). This study proposes how and why solar energy is important for drying the agricultural products. This study aims to expand the domain of solar collector for different purposes and, most important, for agricultural resource normally found in the literature.

The paper opted for an exploratory study using the flat-plate solar collector with drying chamber for drying purposes of agricultural products. During the experiment, the data were collected with moisture content, drying rate of the product and solar irradiation falls on the collector.

This paper describes that how flat-plate collector works for agricultural products and how to reduce the moisture content in the product (fig). Efficiency of collector was evaluated under the ambient temperatures of 24°C. Efficiency also significantly increased from 53 to 55 per cent with an increase in ambient temperature from 22 to 24 °C. Figs (Ficus carica L) were dried in the drying chamber of the flat-plate solar collector. The products were dried at temperature of 55-65°C and 15 to 20 per cent humidity.

Because of this research chosen, the research results are beneficiary for agricultural users for drying purposes. Therefore, the researchers are encouraged to dry the agricultural product with flat-plate solar collector, because it reduced the moisture content of the product very fast.

This paper fulfills an identified need to study that how flat-plat solar collector can be used.

This paper aims to build and empirically test a multilevel framework integrating transaction cost economics and a resource-based view into a value co-creation ecosystem perspective to explain the chain- and firm-level effects of transaction-specific investments (TSIs) on supplier performance.

This paper investigates cross-level network effects using survey data from the List of Taiwanese Central Satellite Production Systems. A total of 34 buyers (hub firms) and 106 suppliers (satellite firms) from 34 supply chains responded to the survey.

Findings confirm that individual firms’ TSIs can foster co-specificity at the supply chain level, thereby improving supply chain integration (SCI). SCI can have a positive cross-level moderating effect on the TSI–performance relationship.

These two key concepts, value co-creation and co-specificity, extend the theoretical application of transaction cost theory and the resource-based view to cross-level study by contributing to the research on the TSI–performance relationship.

This study’s framework is a counter to the buyer–supplier–supplier relationships in which each actor who may have different goals can create value jointly and share benefits from their TSIs.

Owing to high co-specificity, being embedded in a well-integrated supply chain can be a threat when the environment is turbulent; for losing strategic flexibility, co-specificity and embeddedness may result in a collective adaptation concern. High degrees of SCI may slow the reaction to environmental turbulence for both buyers and suppliers.

Individual firms’ TSIs can foster co-specificity at the supply chain level, subsequently enhancing SCI. An integrated supply chain can be a collective asset that facilitates value co-creation. Individual firms can benefit from the sharing of collective value. SCI can also increase switching costs, thus reducing the likelihood of individual firm engaging in opportunistic behavior and cost safeguarding.

With the ability of linking distant partners and diverse bodies of students and faculty, virtual design studios provide unique opportunities for examining cultural, contextual, and methodological differences in design and design collaboration. However, most evaluations of virtual design studio in the recent literature have focused primarily on technical and operational issues. In contrast, the social and cultural dimensions of virtual design studio and their pedagogical implications have not been adequately examined. To address this gap, this article examines the experience and outcomes of a recent virtual design studio involving international collaboration between faculty and student partners. Specifically, it looks at how presence of differences and process of dialogic learning create pedagogical opportunities in a collaborative 'virtual' environment. Based on the case study, this article argues that through dialogues, collaboration, and negotiation of cultural, contextual and methodological differences, collaborative virtual design studio offers an alternative to traditional design studio based on the primacy of individual practice and the master-apprentice model of learning. By creatively utilizing the collaborative environment involving diverse partners, virtual design studio can foster a critical understanding of cross-cultural design process and the significance of dialogues and negotiation in design.

The purpose of the paper is to propose an efficient, simple and concise unified robot calibration method that simultaneously considers errors in hand-eye parameters, kinematic parameters and tool center point (TCP) position.

This paper proposes a unified robot calibration method. First, the initial hand-eye matrix and TCP position are computed without considering kinematic parameter errors. Second, the nominal TCP positions in the laser tracker coordinate system {S} are computed. The actual TCP positions in {S} are directly measured. Third, a unified parameter error calibration model is established, and the sequential quadratic programming algorithm is used for error identification. Finally, the identified errors are used for direct error compensation.

Simulation results prove that the proposed scheme can accurately calibrate the hand-eye parameters, kinematic parameters and TCP position simultaneously. Experimental results reveal that the maximum value of the absolute positioning errors is reduced from 5.4725 mm to 0.4095 mm (reduced by 92.52%). Thus, the proposed approach meets the accuracy requirements of most robotic applications.

The main contributions of this paper are: (1) this scheme is efficient. The method can achieve fully automatic calibration by incorporating Kronecker products for the initial hand-eye matrix and TCP position computation. Thereby significantly improving the calibration efficiency and liberating the labor force. (2) This scheme is simple and concise. The hand-eye parameters, kinematic parameters and TCP position errors are modeled in a unified framework. Furthermore, the related redundant parameters are deleted.

This paper aims to estimate contact location from sparse and high-dimensional soft tactile array sensor data using the tactile image. The authors used three feature extraction methods: handcrafted features, convolutional features and autoencoder features. Subsequently, these features were mapped to contact locations through a contact location regression network. Finally, the network performance was evaluated using spherical fittings of three different radii to further determine the optimal feature extraction method.

This paper aims to estimate contact location from sparse and high-dimensional soft tactile array sensor data using the tactile image.

This research indicates that data collected by probes can be used for contact localization. Introducing a batch normalization layer after the feature extraction stage significantly enhances the model’s generalization performance. Through qualitative and quantitative analyses, the authors conclude that convolutional methods can more accurately estimate contact locations.

The paper provides both qualitative and quantitative analyses of the performance of three contact localization methods across different datasets. To address the challenge of obtaining accurate contact locations in quantitative analysis, an indirect measurement metric is proposed.

The purpose of the paper is to propose an efficient and accurate force/torque (F/T) sensing method for the robotic wrist-mounted six-dimensional F/T sensor based on an excitation trajectory.

This paper presents an efficient and accurate F/T sensing method based on an excitation trajectory. First, the dynamic identification model is established by comprehensively considering inertial forces/torques, sensor zero-drift values, robot base inclination errors and forces/torques caused by load gravity. Therefore, the sensing accuracy is improved. Then, the excitation trajectory with optimized poses is used for robot following and data acquisition. The data acquisition is not limited by poses and its time can be significantly shortened. Finally, the least squares method is used to identify parameters and sense contact forces/torques.

Experiments have been carried out on the self-developed robot manipulator. The results strongly demonstrate that the proposed approach is more efficient and accurate than the existing widely-adopted method. Furthermore, the data acquisition time can be shortened from more than 60 s to 3 s/20 s. Thus, the proposed approach is effective and suitable for fast-paced industrial applications.

The main contributions of this paper are as follows: the dynamic identification model is established by comprehensively considering inertial forces/torques, sensor zero-drift values, robot base inclination errors and forces/torques caused by load gravity; and the excitation trajectory with optimized poses is used for robot following and data acquisition.

The purpose of this paper is to propose a smooth double-spline interpolation method for six-degree-of-freedom rotational robot manipulators, achieving the global C2 continuity of the robot trajectory.

This paper presents a smooth double-spline interpolation method, achieving the global C2 continuity of the robot trajectory. The tool center positions and quaternion orientations are first fitted by a cubic B-spline curve and a quartic-polynomial-based quaternion spline curve, respectively. Then, a parameter synchronization model is proposed to realize the synchronous and smooth movement of the robot along the double spline curves. Finally, an extra u-s function is used to record the relationship between the B-spline parameter and its arc length parameter, which may reduce the feed rate fluctuation in interpolation. The seven segments jerk-limited feed rate profile is used to generate motion commands for algorithm validation.

The simulation and experimental results demonstrate that the proposed method is effective and can generate the global C2-continuity robot trajectory.

The main contributions of this paper are as follows: guarantee the C2 continuity of the position path and quaternion orientation path simultaneously; provide a parameter synchronization model to realize the synchronous and smooth movement of the robot along the double spline curves; and add an extra u-s function to realize arc length parameterization of the B-spline path, which may reduce the feed rate fluctuation in interpolation.

The purpose of this paper is to explore how sales compensation disclosure, salespeople’s perception of corporate social responsibility (CSR) toward customers (i.e. customer-focused CSR), regulatory knowledge and coworkers’ ethical behavior may influence life insurance salespeople’s moral intensity and intentions to engage in misleading sales behaviors.

The hypotheses are analyzed using partial least squares (PLS) regression with the data gathered from full-time life insurance salespeople in Taiwan.

The main findings indicate that disclosing sales compensations will alter the ethical decision-making process of life insurance salespeople. The findings further point out that customer-focused CSR is an important variable affecting moral intensity and ethical intentions.

There has not been any research on the effects of compensation disclosure on moral intensity and misleading sales behavior. The literature gap has led to a poor understanding of the relationship between the compensation disclosure policy and ethical sales behavior. Moreover, previous studies indicate that specific factors (such as moral intensity and ethical intention) are directly associated, while the research shows that as long as a regulatory policy (e.g. the policy of compensation disclosure) changes, the correlation between these variables may shift from significant to nonsignificant (or vice versa). The results are interesting enough to warrant more research, and they also show that the direct link between variables mentioned in previous research is not always stable or universal.