Jinsong Bao

M2M Security Technology of CPS Based on Blockchains

As the core of intelligent manufacturing, cyber-physical systems (CPS) have serious security issues, especially for the communication security of their terminal machine-to-machine (M2M) communications. In this paper, blockchain technology is introduced to address such a security problem of communications between different types of machines in the CPS. According to the principles of blockchain technology, we designed a blockchain for secure M2M communications. As a communication system, M2M consists of public network areas, device areas, and private areas, and we designed a sophisticated blockchain structure between the public area and private area. For validating our design, we took cotton spinning production as a case study to demonstrate our solution to M2M communication problems under the CPS framework. We have demonstrated that the blockchain technology can effectively solve the safety of expansion of machines in the production process and the communication data between the machines cannot be tampered with.

A Steerable GA Method for Block Erection of Shipbuilding in Virtual Environment

Solving the dispatch and optimization of block erection of shipbuilding is a complex problem, especially when the spatial constraints are considered. The block erection scheduling problem can be defined as an identical parallel machine scheduling problem with precedence constraints and machine eligibility (PCME) restrictions, as well as limited layout space. An enhanced genetic algorithm (GA) is proposed to find the near-optimal solution, and a few lower bounds. Also, the percentage of the reduced makespan is defined to evaluate the performance of the proposed algorithm. The proposed GA method of steering optimization produces quicker and lesser values of makespan than the RANDOM heuristic algorithm for the collected real instances. It not only allows users to steer a computing towards effective direction and leverages computing, but also is guided by the intelligence of human to get a global view when the users are in immersive environment. The dispatch of block erection to the crane is modeled into a parallel machine scheduling problem with spatial constraints. Meanwhile a 3D layout of block erection is modeled with real size, and an interactive GA optimization is developed to solve this problem with the objective of minimizing makespan.

Double Closed-Loop Motor Modeling and Analysis for Lunar Rover Simulation

Motor drive control is the major study field in the development of lunar rover. Based on the double-closed DC loop adjustable-speed system, a motor drive simulation module using a position recursive PID control algorithm is developed, which is integrated into the multi-body dynamics simulation system, to carry out the whole lunar rover simulation. And the cruise process of lunar rover locomotion in the complex lunar terrain is simulated in a virtual environment.

A Virtual Assembly Fat Model for Cooperative Assembly Processes of Large-Scale Product

Large-scale, complex products are designed collaboratively by different global manufacturers. This leads to problems of deciding manufacturing tolerance of production’s quality in the final assembly process. A new virtual assembly model, called VAFM (Virtual Assembly Fat Model), is presented in the paper. It integrates not only nominal CAD geometry, but also non-geometry information (geometric dimensions and tolerances (GD&T), bill of materials (BOM), process specifications, assembly deform and inspection data). All information of the model will evolve, mature and derived gradually from “thin” to “fat” during the whole cooperative assembly process. The paper presents the definition of a VAFM, its framework and the evolution rules of the fat model. The paper also presents a modeling language based on XML and its visualization. Finally, a case showing the evolution of the VAFM in the assembly process is illustrated.

Terramechanics Model and Motion Control Strategy Simulation for down-Slope Travel of a Lunar Rover

Slopes are a typical terrain of the rugged lunar surface. Using a modified model for wheel-terrain interaction, a terramechanics model for down-slope travel of a lunar rover is established. In order to describe the soil sinkage of different wheels more accurately, soil deformation by the front wheels is taken into account and the front and rear wheel sinkages are calculated separately. Finally, a motion control strategy for rover descent is proposed based upon analysis of its descending course, and validated by simulation in a 3D lunar rover visual simulation platform.

Joint-Saliency Structure Adaptive Kernel Regression with Adaptive-Scale Kernels for Deformable Registration of Challenging Images

This paper proposes a locally adaptive kernel regression with adaptive-scale kernels for deformable image registration with outliers (i.e., missing correspondences and large local deformations). The adaptive kernel regression locally constructs dense deformation fields from the weighted contributions of each pixel’s surrounding discrete displacement fields in a moving anisotropic kernel by exploiting the contextual deformations of the corresponding saliency structures in the two images. Specifically, we first propose an effective superpixel-based structure scale estimator to estimate the boundary-aware structure scale of each reference structure. We further propose an edge-aware mismatch scale measuring the mismatch degree of the edge structures to be matched in the images. By combining the boundary-aware structure scale with the edge-aware mismatch scale of the underlying saliency structures to be matched, we define edge-aware adaptive-scale kernels for the locally adaptive kernel regression to efficiently construct deformations for deformable registration with outliers. The experiments show that the proposed method achieves not only state-of-the-art matching accuracy for normal corresponding structures but also the best matching efficiency for outlier structures in deformable image registration.

M&E-NetPay: A Micropayment System for Mobile and Electronic Commerce

As an increasing number of people purchase goods and services online, micropayment systems are becoming particularly important for mobile and electronic commerce. We have designed and developed such a system called M&E-NetPay (Mobile and Electronic NetPay). With open interoperability and mobility, M&E-NetPay uses web services to connect brokers and vendors, providing secure, flexible and reliable credit services over the Internet. In particular, M&E-NetPay makes use of a secure, inexpensive and debit-based off-line protocol that allows vendors to interact only with customers, after validating coins. The design of the architecture and protocol of M&E-NetPay are presented, together with the implementation of its prototype in ringtone and wallpaper sites. To validate our system, we have conducted its evaluations on performance, usability and heuristics. Furthermore, we compare our system to the CORBA-based (Common Object Request Broker Architecture) off-line micro-payment systems. The results have demonstrated that M&E-NetPay outperforms the .NET-based M&E-NetPay system in terms of performance and user satisfaction.

A human–machine interaction approach of block erection schedule with three-dimensional spatial constraints

When the spatial constraints are taken into account, the problem about dispatch and optimization of block erection in shipbuilding becomes more complicated. A human–machine interaction approach is proposed and extended to quickly find an approximate optimal solution. First, a steer genetic algorithm enables users to guide the computing to an effective iterative direction and leverages the computing. The model of block erection dispatch to the crane is a parallel machine scheduling problem with spatial constraints. The genetic crossover operators can be guided according to the activities of block erection in shipbuilding. Two criteria are presented to justify the effectiveness of the proposed algorithm and a fitness function is given to represent the makespan. Moreover, three-dimensional spatial constraints, which affect the parallel machine scheduling problem heavily, are visualized. A better erection path can be obtained dynamically, when the users are in an immersive environment. Finally, a three-dimensional layout prototype system of block erection is developed with real size, embedded with an interactive genetic algorithm optimization to solve this problem with the objective of minimizing makespan.

The Site Visualization and Closed-Loop Control for 3D Assembly Process

With the rapid development of 3D CAD technology, 3D assembly process is playing an important role in the on-site assembly. A closed-loop control method and three-dimensional site visualization technology site is presented. The methodology takes into account CAD design stage, assembly process design, site assembly and site inspection. The method includes three key technologies: the verification process technology of three-dimensional assembly process, optimization and process simulation techniques of site assembly, closed-loop control technology of assembly process quality inspection. Finally, the method and technology has applied in the actual assembly, and achieved good results.

Information Modeling and Visualization of Assembly Fat Model for Large-Scale Product

Assembly processes are very complex and hard to setup in one-time for large-scale products. Much assembly information is produced in various assembly processes and such information has not integrated or considered for next assembly processes. This leads to problems of deciding manufacturing tolerance of productions quality in the final assembly process. An object-oriented assembly information model and visualization for VAFM (Virtual Assembly Fat Model), is presented in the paper. The information modeling for assembly processes considers not only geometry data, but also non-geometry information, and those information produced by assembly process evolve, mature and derived during the whole assembly process. The paper presents modeling language based on XML and distributed storage based BSON for assembly object. The visualization of VAFM is also presented.