Beihang University
Assembly Line
Multi-granularity service composition in industrial cloud robotics
Industrial cloud robotics employs cloud computing technology to provide various operational services, such as robotic control modules that enable customized screwing and welding. Service composition technology enables the flexible implementation of complex industrial robotic applications based on the collaboration of multiple industrial cloud robotic services. Most studies considered cloud robotic services with a single robotic manipulator with a fixed function. To utilize the advantages of coarse-grained services encapsulated by multi-functional robots, manipulators, and control applications, a multi-granularity service composition method is introduced considering the multi-functional resources and capabilities of the cloud robotic services. Then a quality-of-service-aware multi-granularity robotic service composition model is built to evaluate the composition solution. Furthermore, a multi-granularity robotic service matching strategy is proposed according to the matching constraints of coarse-grained services. Six representative multi-objective evolutionary algorithms are adopted to optimize five quality-of-service attributes of the composite service simultaneously. Experiments demonstrate that the proposed multi-granularity robotic service composition method can remarkably improve the quality of robotic composite services for complex manufacturing tasks by utilizing coarse-grained services in addition to fine-grained services. The performances of six multi-objective evolutionary algorithms are compared to determine the most suitable algorithm for the multi-granularity robotic service composition problem.
Materials, physics and systems for multicaloric cooling
Calls to minimize greenhouse gas emissions and demands for higher energy efficiency continue to drive research into alternative cooling and refrigeration technologies. The caloric effect is the reversible change in temperature and entropic states of a solid material subjected to one or more fields and can be exploited to achieve cooling. The field of caloric cooling has undergone a series of transformations over the past 50 years, bolstered by the advent of new materials and devices, and these developments have contributed to the emergence of multicalorics in the past decade. Multicaloric materials display one or more types of ferroic order that can give rise to multiple field-induced phase transitions that can enhance various aspects of caloric effects. These materials could open up new avenues for extracting heat and spearhead hitherto unknown technological applications. In this Review, we survey the emerging field of multicaloric cooling and explore state-of-the-art caloric materials and systems (devices) that are responsive to multiple fields. We present our vision of the future applications of multicaloric and caloric cooling and examine key factors that govern the overall system efficiency of the cooling devices.