In this paper, a novel simultaneous wireless power and data transfer (SWPDT) system is proposed for underwater wireless sensor networks. A pair of coils is used to establish forward power transfer and bidirectional data transfer links based on coupled magnetic resonance. While transmitting power to the load, the forward power waves are also used as the carrier for data transfer, thereby avoiding the use of an additional carrier source on the power transmitter-side. An improved double-LCC double-CLC topology is presented to achieve both impedance matching and wave filtering of the SWPDT system in full-duplex mode, instead of using additional wave trappers, transformers or tap coils. Compared with previous works, the proposed system can simultaneously achieve high power gains, low mutual interference and simple circuit structure. Moreover, to deal with the conflicts between the power gains and the bandwidths of the channels, an improved multi-objective optimization method is proposed for the SWPDT system. Using this method, the Pareto optimal solutions of the system parameters can be found and the comprehensive performance of the SWPDT system can be further improved. Finally, an experimental prototype is established, which achieves full-duplex wireless power and data transfer, with a maximum load power of 23.1W, a forward data transfer rate of 20kbps and a backward data transfer of 300kbps. There is almost no interference between power and data transfer. The experimental results show that the proposed SWPDT system has good application prospects in underwater sensor node charging and full-duplex communication.

Cooperative autonomous exploration is a challenging task for multi-robot systems, which can cover larger areas in a shorter time or path length. Using multiple mobile robots for cooperative exploration of unknown environments can be more efficient than a single robot, but there are also many difficulties in multi-robot cooperative autonomous exploration. The key to successful multi-robot cooperative autonomous exploration is effective coordination between the robots. This paper designs a multi-robot cooperative autonomous exploration strategy for exploration tasks. Additionally, considering the fact that mobile robots are inevitably subject to failure in harsh conditions, we propose a self-healing cooperative autonomous exploration method that can recover from robot failures.

In order to improve the subjective and objective consistency of image sharpness evaluation while meeting the requirement of image content irrelevance, this paper proposes an improved sharpness evaluation method without a reference image. First, the positions of the edge points are obtained by a Canny edge detection algorithm based on the activation mechanism. Then, the edge direction detection algorithm based on the grayscale information of the eight neighboring pixels is used to acquire the edge direction of each edge point. Further, the edge width is solved to establish the histogram of edge width. Finally, according to the performance of three distance factors based on the histogram information, the type 3 distance factor is introduced into the weighted average edge width solving model to obtain the sharpness evaluation index. The image sharpness evaluation method proposed in this paper was tested on the LIVE database. The test results were as follows: the Pearson linear correlation coefficient (CC) was 0.9346, the root mean square error (RMSE) was 5.78, the mean absolute error (MAE) was 4.9383, the Spearman rank-order correlation coefficient (ROCC) was 0.9373, and the outlier rate (OR) as 0. In addition, through a comparative analysis with two other methods and a real shooting experiment, the superiority and effectiveness of the proposed method in performance were verified.

As the core element of adaptive optical systems, tuneable lenses are essential in adaptive optics. Dielectric elastomer-driven tuneable lenses offer significant advantages in tuning range, response speed, and lightweight design compared to traditional mechanical zoom lenses. This paper systematically reviews the working mechanisms and research advancements of these lenses. Firstly, based on the two driving modes of deformation zoom and displacement zoom, the tuning principle of dielectric elastomer-driven tuneable lenses is analysed in depth. Secondly, the design methodology and current status of the research are systematically elaborated for four typical structures: monolithic, composite, array, and metalenses. Finally, the potential applications of this technology are discussed in the fields of auto-zoom imaging, microscopic imaging, augmented reality display, and infrared imaging, along with an analysis of the key technological challenges faced by this technology, such as material properties, modelling and control, preparation processes, and optical performance. This paper aims to provide a systematic reference for researchers in this field and to help promote the engineering application of dielectric elastomer tuneable lens technology.