Applied Mechanics and Materials Vols. 48-49

Abstract: This paper employs Bumblebee2 stereo vision system to detect the obstacles for patrol robot in substation environment. Firstly, with the selected points in the disparity image, the ground plane is calculated by the RANSAC (Random Sample Consensus) algorithm. And then, the local occupancy grid map is built for patrol robot, and the obstacles are detected through connected component analysis method. The actual test in substation environment verified the reliability of the system.

Abstract: Facing to the shortcoming of Affinity Propagation algorithm (AP), we present two expanded and improved AP algorithms. In the two algorithms, the AP algorithm based on Grid Cell (APGC) is an effective extension of AP algorithm on the level of grid cells, and the AP clustering algorithm based on Near neighbour Sampling (APNS) is trying to make some improving in time and space complexity. From some simulated comparison experiments of three algorithms, we know that APGC and APNS algorithms have evident improving than AP algorithm in time and space complexity. They can not only get a good clustering quality for massive data sets, but also filtrate noises and isolates well. So we can say they are two effective clustering algorithms with much applied prospect. At last, several research directions are presented.

Abstract: The dynamic model of the synchronous balancing system of huge-scale hydraulic press was set up based on analyzing of force acted on 800MN huge scale hydraulic press’s moving beam .A self-tuning PID controller was designed and simulated by using the MATLAB fuzzy logic too1．The simulation result shows that it is very effective to overcome the eccentric load and parameter variety ,in additon ,in order to check the real control efficency , The related experiments were carried on the 315T experimental test special-purpose press as well as simulation anylyzing ,which was built for 800MN huge scale hydraulic press’s design and anylyzing.The results both show that the hydraulic press’s synchronization system with the fuzzy self-tuning PID controller has a slight overshoot，rapid response and high accuracy.

Abstract: In this paper, a method of automatic NC code programming is studied. The data structure used to store graph information is the base of automatic programming system. By utilizing the object-oriented tree data structure proposed in the paper, the disadvantages of the method caused by using simple data structures can be overcome. In processing information, the judgment of topological relationship between two outlines is very important. The Loop Extremum Method is easy, convenient and with no limitations. The system adds plenty of technological parameters, provides multiple machining patterns. In the end, an example is given to test and verify the system`s functions.

Abstract: A new method of online monitoring ICE powers based on the crankshaft angular vibration is proposed. It has deduced that when each cylinder works uniformly at a certain rotating speed, and the vth order angular vibration mode of crankshaft nears plane vibration mode such as “quasi-rigid body model” or “quasi-trapeziform model”, so a cubic polynomial can represent the relationship between the vth order angular vibration displacement amplitude of the crankshaft reference point and the engine powers, thereby the angular vibration of reference point could be used to online monitor engine powers. Through the simulation and experimental researches on a 6240 and a 4100 diesel engine, it shows that the engine powers fitted with the angular vibration displacement amplitudes of reference point are close to the measured or theoretical powers comparatively, and the maximum errors is only 2.95%, which verifies the feasibility and practicability of the method consequently.

Abstract: The integral steering linkage is the key part on vehicle, which can ensure the Ackerman steer angle when steering. in this paper, The mathematical model of the Ackerman steering linkage is established. The author introduces the optimal design program for the Ackerman steering linkage with MATLAB optimtoolbox. With the program, users can obtain optimized calculating results by inputting basic structural parameters. Actual output angle and expected input angle curves variation with input angle is automatically drawn so as to facilitate users for analysis, comparison and selection. The proposed method is accurate and efficient to design the splitting Ackerman steering linkage.

Abstract: Aiming at the deformation of the mast of rotary drilling rig, 3D graphics software Pro/E and finite element analysis software Ansys are applied to model and optimize the structure of the mast. Back sliding wheel installed on the mast of rotary drilling rig is firstly proved to be effective to reduce the deformation of the mast of rotary drilling rig. On this basis, the distance between back sliding wheel and the mast of rotary drilling rig, and the position of the pulley yoke are adjusted together to obtain the minimum deformation of the mast of rotary drilling rig, which improves the stability of the mast of rotary drilling rig in the course of construction, and provides theoretic supports for more optimization design and research of the mast of rotary drilling rig.

Abstract: According to the working requirement of large-scale cross roller slewing bearing used in special propeller, an optimal design model which includes objective function, optimization variables and constraints is established, and uses genetic toolbox of the Matlab software to solve the mathematical model. An example shows that the bearing’s life is improved significantly by the optimization. It indicates that the optimization design has some guidance significance in the design process of the slewing bearing.

Abstract: The global climate change require human production and life must go into the low carbon times of low energy consumption,low emission and low pollution objectively, and now the low carbon development of electric power industry becomes the important link to realize the aim of energy saving and emission reduction. With the necessity analyses of carbon emission reasonable control in electric power production, this paper first proposed the thought of regional electric power overall low carbon，then comprehensive summary origin measures from generation side, transmission side and consuming side. This paper set up the optimization system of regional electric power low carbon, proposed the development degree and combination weight model to empirical study,which provide the effective theoretical basis for low carbon concrete measures.

Abstract: We present a combination of feedforward and regulatory control system to implement optimal grade transition operation of a continuous stirred tank reactor (CSTR) that must produce several grades of polymers. When the target polymer quality grade is specified, a two-step approach is adopted to implement the optimal grade transition operation. The dynamic optimization is carried out to minimize the amount of initiator assumption during the transition operation as well as to shorten the transition time. Through case study of a free radical styrene polymerization, it is shown that both transition time and initiator assumption are superior to those of a regulatory control system.