Applied Mechanics and Materials Vols. 10-12

Abstract: The force of control column is very important for the pilot in a flight simulator. So the control loading system in the flight simulator has been concerned since the flight simulator appeared. As the force command signal generated part of control loading system, flight control system module is the most important module for the fidelity of control loading system. This paper described a method to build flight control module. We used SimMechanics in simulink to model and analyze the feel and centering unit, which is the key part of feeling system in the flight control system, and in this paper we described the structure of the control loading system, and the function of the feel and centering unit.

Abstract: This paper presents an automatic pipe-routing algorithm for pipelines with branches in an electromechanical product. The algorithm uses chaos theory to establish the chaos grid pre-processing model (CGPM) that can efficiently pick up solution space and reduce the search range. A novel particle swarm optimization (PSO) algorithm is developed to seek for an approximate optimal trajectory in the solution space. Experiments show that the modified PSO algorithm is effective and efficient. The examples demonstrate that the automatic pipe-routing algorithm is effective and practical for pipelines with branches.

Abstract: In order to find an optimum assembly sequence in engineering design domain, a knowledge-based virtual assembly approach was put forward. Virtual assembly design environment was also introduced, and knowledge representation models for virtual assembly rules and cases are introduced and studied respectively. A side-center virtual assembly method was applied to avoid the occurrence of assembly interference. Finally, a case was employed to demonstrate the practicality of knowledge-based virtual assembly planning.

Abstract: With the analysis of assembly course of some large-scale products, a new man-machine interactive system for virtual assembly of such products that can realize the operator’s free walking is put forward. The system architecture and key techniques involved are explored and some research results in advance are also supplied.

Abstract: Due to complex process and high difficult operation for large-scale products assembly, the application of virtual assembly (VA) has an important significance and also an actual value. In this paper the key techniques of VA for large-scale complex products are proposed, and their assembly characteristics (such as their organization form, human participation, process planning and optimization and so on) are analyzed. First, a new virtual environment (VE) system considering human activities is set up. Second, an integration approach is realized to transform data from CAD to VA system, and a hybrid method on the basis of virtual reality (VR) and intelligent algorithm is applied to optimize and evaluate assembly process planning. Moreover, assembly documents generation and Web training for assembly workers are implemented. Finally, an application case of the VA system for a complex product is given, and further work is pointed out.

Abstract: Maximally utilizing the capabilities offered by the feed drive systems in the CNC machining can both increase productivity and improve product quality. In this study, a framework of off-line feed rate scheduling was presented and a turning machining simulation and feed rate optimal system was developed. The system take advantage of virtual machining acquires cutting parameters and predicts cutting forces and cutting power. Constant cutting power was used as an objective to optimize feed rate, the feed rate in NC program was re-scheduled. The experiment results show that machining time is reduced and machining stability is improved by using the optimized NC program.

Abstract: Virtual prototype technology could integrate different CAD formats parts into an digital model. In this way the design process will be more efficient. This issue reviewed three methods to transfer data from CAD parts to virtual reality element. And find an efficient way to transfer different CAD model data to virtual prototype software Division MockUp.

Abstract: Due to big structure and complex process for some large-scale products (such as planes and rockets), the workers have to try many times and move around in the products to accomplish the assembly operations for high-precision requirements. Thus, the efficiency is low and the cost is high in the assembly process. To deal with that, the virtual assembly (VA) system for large-scale products is developed in this paper. First a new VA environment considering human activity is set up, and then a hierarchical assembly process list (HAPL) model and a dynamic constraint recognition algorithm is proposed to realize exact placement for large-scale products in VA system. Finally, the method is verified by the development VA system which successfully applied in the process of satellite assembly. Moreover, the method can be used in the common VA systems for assembly planning.

Abstract: Biped robot with heterogeneous legs (BRHL) is a new pattern humanoid robot. This paper first introduces the conception, research purpose and configuration of HRHL. Then coordinated dynamics model and magneto-rheological (MR) damper model are given. In the end, this paper discusses the control model of BRHL and gives combined control simulation. The result indicates that intelligent bionic leg controlled by MR damper can track artificial leg’s gait well.

Abstract: For the improvement of the system real-time capability, the DSP Curve Surface interpolator has been designed to ensure high speed, high precision requirement for the machining of complexity curve surface. The hardware and software has been designed. The changeable feedrate interpolation algorithm of limit curve error has been studied. Furthermore, the algorithm has been applied to the interpolation and has well real-time capability to satisfy the requirement of high capability CNC by experimentation.