A wall-climbing robot is a mobile robot that operates on a vertical wall. A wall-climbing robot with dual-propeller is proposed in this paper, in which the aerodynamics of the propeller is an ...important research part. Therefore, the aerodynamics of the propeller is simulated by ANSYS Fluent and experimentally analyzed in this paper. First, the aerodynamic simulation analysis of the single rotor and the double rotor is carried out in this paper, and then the tensile test experiment of the single propeller is carried out by using the pulling machine. Finally, an experimental platform for the whole machine was built, and the tensile test experiment was carried out on the double propellers. It is concluded that the aerodynamic forces generated by the two rotors are not linearly superimposed due to the airflow interference, and the rotational speed of the rotors and the distance between the rotor platforms all affect the magnitude of the force.
Wall-climbing robot can adapt to the wall surface of a variety of different materials, and can perform a variety of tasks, such as cleaning glass curtain walls and inspecting bridges. In this paper, ...a rotor-propeller type wall-climbing robot is researched and developed. The model aircraft propeller is used as the adsorption unit. The rotor platform has one roll degree of freedom, one pitch degree of freedom. Based on the vector superposition method, this paper considers the difference between the support forces of each wheel of the wall-climbing robot, and analyzes the relationship between the wheel and the wall of the wall-climbing robot. Furthermore, the effects of the anisotropic friction of the wheels and the roll joints on the lateral resultant force of the wall-climbing robot are studied. The results show that the roll joint is beneficial to the stable adsorption of the robot on the wall. Finally, a wall motion experiment is carried out in an indoor environment to verify the feasibility of the robot and the correctness of the theory.
As more polices are being applied to reduce the green gas emission, the construction of On-site Hydrogen Refueling Stations (OHRS) is necessary for the popularization of hydrogen powered vehicles. ...One of the most reliable energy resources for an OHRS would be the electric energy purchased from the grid. The electricity market is divided into day-ahead market and real-time market. Considering volatility electricity prices, and uncertainty of hydrogen demand, the paper presents an electricity transaction strategy model for a single OHRS. To avoid the combinatorial "explosion" with the number of uncertainties, by using Stochastic Dual Dynamic Programming (SDDP) algorithm, the expected cost-to-go function is approximated by piecewise linear functions, which improves the solution time. Real historical market data are used in case study. The results show that when the electricity prices and hydrogen loads fluctuate, the proposed model can optimize the electricity transaction strategy for OHRS under the condition of meeting the safety criteria. The study can provide a theoretical method for OHRS for the transaction strategies.
The frequency limit controller, or FLC, is an important measure for grid frequency stability control, and has been widely used in DC projects. DXB UHVDC project is faced with the problems of ...increasing frequency instability of the Yunnan power grid, as it runs asynchronously from the main grid, and the shortage of the opening unit in the initial stage of production. The configuration of FLC is very important. It analyzes two kinds of FLC control logic used in current DC project of China Southern Power Grid and compares the results of two kinds of control logic response through simulation test. The FLC configuration and parameter selection of DXB UHVDC are explained, and the response characteristics of FLC under the typical fault under the isolated islanding system are verified through simulation. And verify its function in DXB R TDS simulation platform as well as field test.
A trajectory tracking control algorithm based on deep reinforcement learning is proposed in this paper. It could solve the trajectory tracking problem of wheeled mobile robot with nonholonomic ...constraints. Firstly, by analyzing the nonholonomic constraint characteristics of the wheeled mobile robot, the kinematics model, dynamics model and motor drive model of the wheeled mobile robot are established. Then, according to the proposed model, a trajectory tracking control algorithm is designed by using the deep deterministic policy gradient (DDPG) algorithm. Finally, a robot agent is trained to tracking a circle trajectory by the proposed method. The simulation results show that our control algorithm could effectively track the target circular trajectory.
Multi-Weather Classification using Evolutionary Algorithm on EfficientNet Zhang, Yulong; Sun, Jingtao; Chen, Mingkang ...
2021 IEEE International Conference on Pervasive Computing and Communications Workshops and other Affiliated Events (PerCom Workshops),
2021-March-22
Conference Proceeding
Complex weather factors seriously affect the quality and accuracy of image processing, and indirectly pose severe challenges to the expansion of IoT applications in smart cities and the actual ...intelligent classification of research. However, the current research on weather classification cannot comprehensively deal with composite weather classification, and the accuracy and processing time are still not satisfactory. This is still a challenge for the popularization of IoT applications. This paper proposes a multi-weather classification method that can intelligently classify the weather elements in the image data collected by the IoT applications. The idea behind us is to propose the evolutionary algorithm into EfficientNet to solve the various weather classification problem. Our experimental results show that we can achieve remarkable classification results with a high degree of confidence in five complex weather conditions, even in pictures with obvious weather characteristics, and the recognition accuracy increases to more than 95%.
Triple-mode and quadruple-mode bandpass filters using triangular half-mode substrate integrated waveguide (HMSIW) are presented. To realize the two multi-mode filters, the triangular HMSIW cavity is ...perturbed by introducing via-hole arrays at different positions of the structure. The perturbation causes mode shifting of certain resonant modes near to the other resonant modes which are not affected in order to form the passband. The first three resonant modes and four high order resonant modes (from the third resonant mode to the sixth resonant mode) in the perturbed triangular HMSIW are respectively utilized to design the triple-mode and quadruple-mode filters. Both filters are fabricated and measured to provide an experimental validation on the predicted performances of the proposed filters.
Driven by new technologies such as cloud computing and AI, the cloud robot has entered a golden period of rapid development. The problem that restricts robot developers in current cloud robot ...research is the lack of a safe way to transmit messages between edge and cloud. Therefore, in this paper, we propose the RCC (Robot Cloud Communication), a Python-based software library, which can help swarm intelligence robots data to be efficiently and securely transferred to different types of business clouds or private cloud platforms. In addition, we integrate the RCC function library and can also provide high-quality data security guarantees for development users when sending and receiving data. Through our approach, we successfully implemented the development of an indoor 3D map application which is difficult to achieve on a single robot platform. Our experimental results show that our RCC is not only very stable in performance of reading and writing, but also shows great performance in data encryption and decryption.
Aim The pharmacokinetic (PK) properties of cyclosporine (CsA) in renal transplant recipients are patient- and time-dependent. Knowledge of this time-related variability is necessary to maintain or ...achieve CsA target exposure. Here, we aimed to identify factors explaining variabilities in CsA PK properties and characterise time-dependent clearance (CL/F) by performing a comprehensive analysis of CsA PK factors using population PK (popPK) modelling of long-term follow-up data from our institution. Methods In total, 3,674 whole-blood CsA concentrations from 183 patients who underwent initial renal transplantation were analysed using nonlinear mixed-effects modelling. The effects of potential covariates were selected according to a previous report and well-accepted theoretical mechanisms. Model-informed individualised therapeutic regimens were also conducted. Results A two-compartment model adequately described the data and the estimated mean CsA CL/F was 32.6 L h-1 (5%). Allometrically scaled body size, haematocrit (HCT) level, CGC haplotype carrier status, and postoperative time may contribute to CsA PK variability. The CsA bioavailability in patients receiving a prednisolone dose (PD) of 80 mg was 20.6% lower than that in patients receiving 20 mg. A significant decrease (52.6%) in CL/F was observed as the HCT increased from 10.5% to 60.5%. The CL/F of the non-CGC haplotype carrier was 14.4% lower than that of the CGC haplotype carrier at 3 months post operation. CsA dose adjustments should be considered in different postoperative periods. Conclusions By monitoring body size, HCT, PD, and CGC haplotype, changes in CsA CL/F over time could be predicted. Such information could be used to optimise CsA therapy.