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2021 ◽  
Vol 14 (1) ◽  
pp. 16
Author(s):  
Konstantin P. Kolotyrin ◽  
Sergey A. Bogatyrev ◽  
Yuri Yu. Kostyukhin ◽  
Diana Yu. Savon ◽  
Alexey I. Shinkevich

The article is devoted to the substantiation of technological foundations for the restoration of extremely worn-out, metal-consuming, and resource-consuming parts, in a method consisting of applying a compensating metal wear with subsequent plastic deformation. Currently, there are no technologies for their restoration in a repair facility that guarantee the resilience of the factory product. The proposed technological process of repair consists of butt welding onto the end of the spline semi-axle shank, compensating for the wear of the metal, the volume of which takes into account the losses resulting from the wear of the slots, as well as allowances for their machining. In the example of forging the axle shaft of a truck’s driving axle, the regularities of the plastic flow of metal during part deformation in the stamp are revealed. In the process of hot volumetric upsetting of long cylindrical parts with a variable diameter, it is important to know the possible directions of metal movements, as well as the energy-power characteristics of the process at various stages of forging. The evaluation criteria of the level of perfection of the technology were indicators of resource conservation and efficiency of the recovery route. The technological direction of the conducted research was analyzed, step by step, from the standpoint of saving repair materials and energy resources. The results of theoretical studies are crucial in the design of die tooling, for the manufacture of blanks, when restoring the rear axle shafts of trucks with pressure. Production tests carried out on the models, obtained as a result of mathematical processing of experimental data, confirmed the reliability of the experimental information. The introduction of the proposed set of repair equipment for the restoration of semi-axles will allow the formation of additional production in the region for the recycling of worn-out metal-intensive steel parts of agricultural machinery.


2021 ◽  
Author(s):  
Hui Bian ◽  
Chun Zhang ◽  
Shi-Jie Wang ◽  
Jia-Chen Li ◽  
Xue-Lei Xie ◽  
...  

Abstract A new wheeled rolling robot is designed based on planar 3-RRR parallel mechanism and spoke wheel with variable diameter, by adjusting the 3-DOF outputs of the planar 3-RRR parallel mechanism, the deformation and rolling motion of the rolling robot are realized, the rotation output of the parallel mechanism realizes the differential change of the diameter of the two supporting wheels of the rolling robot, and the moving output of the parallel mechanism changes the mass distribution of the system, so that the rolling robot can complete the forward, backward, turning and other motions. Based on the introduction of the performance parameters, driving system, variable diameter wheel configuration and motion mechanism of the rolling robot, the eccentric driving torque is analysis and the existing space of the eccentric torque is given, so as to further complete the selection of the driving motor of the robot. This article analysis three typical motions of robots and its performance parameters, such as straight movement, turn movement, climbing exercise, and builds a simple prototype under laboratory conditions to verify the feasibility of the three movements.


2021 ◽  
Vol 2066 (1) ◽  
pp. 012099
Author(s):  
Qian Li ◽  
Yongyi Fang ◽  
Baoan Liu ◽  
Kun Xing ◽  
Lijun Wang ◽  
...  

Abstract The detection of pipeline in service is very important, but the existing manual detection has blind spots, long cycle, high risk, low precision and high cost. Therefore, it is very important to develop a mobile detection robot to replace manual inspection. This paper mainly introduces the control strategy of pipeline robot. In this paper, the overall control structure of the pipeline robot system is built, including the design of hardware framework and the design of software implementation process. Hardware design includes the selection design of microcontroller ARM, sensor, motor driver and so on. The software design is mainly the process design of action realization and the frame design of man-machine interactive operation panel structure. After the system construction is completed, the motion control experiment of the pipeline robot control system is carried out to test the walking performance of the pipeline robot prototype in the vertical variable diameter pipeline, and the motion control experiment is carried out to verify the rationality of the mechanical structure of the pipeline robot and the practicability of the control system.


Robotica ◽  
2021 ◽  
pp. 1-16
Author(s):  
Chen Yang ◽  
He Xu ◽  
Xin Li ◽  
Fengshu Yu

Abstract This paper presents a method to solve the kinematics of a rigid-flexible and variable-diameter continuous manipulator. The multi-segment underwater manipulator is driven by McKibben water hydraulic artificial muscle (WHAM). Considering the effect of elasticity and friction, we optimized the static mathematical model of WHAM. The kinematic model of the manipulator with load is established based on the hypothesis of piecewise constant curvature (PCC). We developed an optimization algorithm to calculate the length of the WHAMs according to the principle of minimum strain energy and obtain the configuration space parameters of the kinematic model. Based on the infinitesimal method, the homogeneous transformation matrices of the variable-diameter bending sections are computed, and the terminal position and attitude are obtained. In this paper, we studied the working space of the manipulator by quantitative analysis of the impact factors including pressure and load. A deep neural network (DNN) with six hidden layers is designed to solve inverse kinematics. The forward kinematic results are used to train and test the DNN, and the correlation coefficient between the output and target samples reaches 0.945. We carried out an underwater experiment and verified the effectiveness of the kinematic modeling and solution method.


Author(s):  
Simone Maffia ◽  
Valentina Finazzi ◽  
Francesca Berti ◽  
Francesco Migliavacca ◽  
Lorenza Petrini ◽  
...  

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