Suitable trajectories with minimum execution time are essential for an industrial robot to enhance productivity in pick and place operations. A novel point-to-point trajectory planning algorithm (PTPA) is proposed to improve the motion efficiency of industrial robots. The jerk profile for a trajectory model is determined by five intervals and the jerk constraint. According to the kinematic constraints and two shape coefficients, a velocity threshold and three displacement thresholds are calculated for an individual joint to transfer the proposed jerk motion profile into four specific profiles. The optimal trajectory model of the joint is developed for the minimum-time and jerk-continuous trajectory via the performance evaluation with the input displacement and three displacement thresholds. Moreover, time-based motion synchronization for all joints is taken into account in PTPA to decrease unnecessary burdens on the actuators. The simulations illustrate that the execution time by PTPA is more efficient than that by other techniques. The experiments of a point-to-point application on a real six-axis industrial robot show that the absolute errors at the end of the motion for all joints are within 0.04°. These results prove that PTPA can be an effective point-to-point trajectory planner for industrial robots

To gain sustainable development, it is a trend that manufacturing companies are change the value chain from manufacturing-centric to service-centric. Therefore, the capability of the manufacturing service is as significant as the production ability of enterprises, which reflects the supply chain management (SCM), flexible production, production efficiency, and other indicators of the enterprises. It is the first paper to discuss the sustainability of service-oriented manufacturing using bibliometric analysis. It derives a detailed review and future outlook on the development of manufacturing servitization, indicating the research directions for future development, and provides a valuable reference for researchers in related directions. The bibliometric analysis discusses countries or regions, research areas, authors, keywords, institutions, and journals based on the literature data from the Web of Science (WoS). The results show that research on manufacturing services has gradually received attention since its inception and has become popular since 2008. The papers published from 2008 to 2021 account for 77.62%. The USA is the most studied country on this topic, followed by China and the UK. The International Journal of Production Research regarding the most quantity of articles, and Beihang University is the most influential institution in this field. The largest amount of articles published in the area of “business and economics”, amounting to 1565 articles. In recent years, the main research areas included “Industry 4.0”, “cloud manufacturing (CMfg)”, “Internet of Things (IoT)”, “big data” and “services innovation”. Finally, “digital and intelligent manufacturing” and “product-service systems” are potential research directions for the future.

A CFD model was presented to simulate the distribution of air velocity and temperature in a greenhouse adopting the fan-pad cooling system in summer. The Boussinesq hypothesis was applied for the simulation of gravitation; the k-ε turbulent model and discrete ordinates model were selected to predict the distribution of air velocity and temperature inside greenhouse using the commercial software Fluent. The differences between simulated and measured air temperature varied from 0.9 to 4°C and the differences of air velocity were less than 0.15 m/s, which proved that the CFD method can estimate the distribution of air velocity and temperature in the greenhouse rationally and effectively. The validated CFD model was then used to evaluate the cooling effect and design the installment of fan and pad in terms of the crop size. The results implied that Case 3 and Case 5 should be chosen when the height of crop canopy varies from 2 m to 3 m. When it varies from 1 m to 2 m, all the cases can be effective except Case 1. When the canopy height is below 1 m, all the cases can be selected. This paper suggested that the CFD model can be used as an optimal tool for fan-pad evaporative cooling system in the greenhouse.