• Volume 20,Issue 4,2022 Table of Contents
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    • SURVEY OF MULTITARGET RENDEZVOUS TRAJECTORY OPTIMIZATION METHODS

      2022, 20(4):1-11. DOI: 10.6052/1672-6553-2021-070

      Abstract (85) HTML (0) PDF 774.62 K (120) Comment (0) Favorites

      Abstract:Multitarget rendezvous can effectively reduce the cost of a single mission and increase the benefit, so it is the first choice for asteroid exploration, inorbit service and other missions in the future. The trajectory optimization problem of such missions involves many variables and huge solution space, so it is difficult to obtain the optimal solution directly. The solution of this problem is usually divided into two steps: first, the rendezvous sequence is optimized, and then, for a given rendezvous sequence, the trajectory of each targettotarget transfer is optimized. Fast and accurate estimation of the transfer cost such as velocity increment or transfer time is needed to optimize the rendezvous sequence. Thus, the trajectory optimization problem of multitarget rendezvous can be divided into three subproblems: transfer cost estimation, rendezvous sequence optimization, and transfer trajectory optimization. In this paper, the methods of solving these three subproblems are summarized.

    • RESEARCH PROGRESS OF PIEZOELECTRIC ENERGY HARVESTING FROM FLOW-INDUCED VIBRATION

      2022, 20(4):12-23. DOI: 10.6052/1672-6553-2021-056

      Abstract (49) HTML (0) PDF 2.49 M (133) Comment (0) Favorites

      Abstract:Flow-induced vibration is a typical phenomenon of fluid-structure interaction. The periodic force caused by flow-induced vibration will cause fatigue damage to the structure, which leads to safety problems. In recent years, with the development of vibration energy harvesting technology and the application of low energy consumption products such as microelectronics, wireless networks and Micro electro mechanical system. The energy capture technology based on flow-induced vibration has attracted more and more researchers’ attention, but at the same time there are many problems in the research of flow-induced vibration technology. The current development status of current flow-induced vibration energy capture technology is reviewed, and several measures to improve the efficiency of flow-induced vibration energy capture devices are discussed. Finally, the current problems and challenges in the field of flow-induced vibration energy harvesting are summarized, and the prospects for the future development of flowinduced vibration energy harvesting are put forward.

    • CONTRADICTIONS IN CALCULATING THE PUISEUX SERIES EXPANSION OF TIMEDELAY SYSTEMS NEAR A REPEATED CHARACTERISTIC ROOT

      2022, 20(4):24-31. DOI: 10.6052/1672-6553-2022-008

      Abstract (42) HTML (0) PDF 398.75 K (103) Comment (0) Favorites

      Abstract:Puiseux series is a mathematical tool for dynamics analysis of time-delay systems near a repeated characteristic root, and it has became a hot research topic in the recent years. This paper presents a new observation that under certain conditions, contradictions occur in calculating the Puiseux series expansion of time-delay systems when the method of undetermined coefficients is used, the reason that leads to contradictions, as well as some normal forms of the correct Puiseux series expansion under some specified conditions, are given.

    • SUMMARY OF METEOROIDS AND SPACE DEBRIS MODEL

      2022, 20(4):32-39. DOI: 10.6052/1672-6553-2021-080

      Abstract (37) HTML (0) PDF 780.25 K (110) Comment (0) Favorites

      Abstract:There are a large number of meteoroids and space debris in space. The growing space objects will undoubtedly bring formidable challenges and negative impacts on the security of future space missions. This article reviews the evolution of meteoroid and space debris models, elaborates on the main characteristics and application scope of each model, and focuses on the rational use of different models from the occurrence of the fragmentation event to the evolution of the total amount of space debris in the future. The paper also studies the relationship between space events and models, compares the advantages and disadvantages of different models, offers scenariospecific suggestions on model selection, and finally envisages China’s own space system model in the future.

    • DYNAMIC STABILITY OF ROTATING THIN CONICAL SHELLS UNDER PERIODIC AXIAL FORCE

      2022, 20(4):40-47. DOI: 10.6052/1672-6553-2021-050

      Abstract (37) HTML (0) PDF 1.43 M (117) Comment (0) Favorites

      Abstract:The dynamic stability of rotating thin conical shells under periodic axial force is studied in this paper. Based on Donnell’s thin shell theory, the motion equation of rotating conical shell is derived. The parametric instability of the system under periodic axial load is analyzed by using the generalized differential quadrature method and Hill’s method. The variations of several instability regions with working conditions and geometric parameters are discussed. The results show that the instability region moves along the frequency axis with the increase of the rotating speed, but the instability width has little effect. Increasing the constant tensile axial load will not only significantly increase the instability width, but also cause the instability region shift to a higher frequency range. The variation of cone angle, thickness to diameter ratio or length to diameter ratio will cause the instability region to move along the frequency axis. Cone angle and thickness diameter ratio will increase the width of instability (length diameter ratio will decrease). With the increase of the number of circumferential waves, the influence of cone angle on the instability region gradually weakens, while the influence of thickness diameter ratio remains unchanged.

    • MODAL ANALYSIS OF BUTTED CYLINDRICAL SHELL STRUCTURE

      2022, 20(4):48-54. DOI: 10.6052/1672-6553-2021-060

      Abstract (43) HTML (0) PDF 2.22 M (105) Comment (0) Favorites

      Abstract:Butted cylindrical shell structure is widely used in aerospace, shipbuilding, civil engineering and mechanical engineering. Modal analysis is an important research direction to study its structural characteristics. This study briefly introduces the modal analysis technology and the basic principle of the polyreference least-squares complex frequency-domain method (PolyMAX), and the finite element modal analysis and experimental modal analysis of butted cylindrical shell structures are carried out. In the process of experimental modal analysis, the experimental realization of the free boundary and the correctness of the analysis results are discussed, and the analysis results are compared with the finite element modal analysis results. The results show that while the butted cylindrical shell structure has the general vibration characteristics of the cylindrical shell structure, the asymmetric vibration with the flange as the boundary occurs due to the existence of the docking form.

    • PIEZOELECTRIC METAMATERIAL DESIGN AND ITS APPLICATION IN ALLEVIATING VIBRATION OF ELASTIC BEAM

      2022, 20(4):55-62. DOI: 10.6052/1672-6553-2021-076

      Abstract (30) HTML (0) PDF 2.00 M (98) Comment (0) Favorites

      Abstract:Metamaterial is a type of composite material structure, in which a cell is repeated periodically with different materials integrated. Owing to the phenomenon that metamaterial structures can form a bandgap in spectrum and make the elastic wave propagation confined in it, they has attracted attentions in the fields of noise and vibration control. In this paper, we proposed a piezoelectric metamarerial, in which a piezoelectric material and a oscillate circuit form the cell. From the theoretical analysis, it is proved that the frequency band gap is generated. Furthermore, this kind of piezoelectric metamaterial is put on a cantilever beam to show the effect of vibration attenuation. The simulation investigation is carried out, including the studies on the vibration energy absorption, the influence of resistance and the vibration attenuation characteristic (combined with the voltage curve on PZT). The results focus on the significance of transmission and voltage, and show that the piezoelectric metamaterial is effective in vibration attenuation.

    • DYNAMICS OF SPACE PLATFORM LAUNCHING SERVER AND OPTIMAL DOUBLE PULSE RENDEZVOUS

      2022, 20(4):63-73. DOI: 10.6052/1672-6553-2021-071

      Abstract (26) HTML (0) PDF 9.16 M (104) Comment (0) Favorites

      Abstract:The paper studies the two-body coupling dynamics between the space platform and server while launching process, as well as energy saving optimization of the double pulse control of the server during rendezvousing and docking to the target satellite. Firstly, the space platform forms an orbiting relationship with the target satellite, keeping its launch tube axis aiming at the target satellite. After receiving the launch command, the server shoots out from the launch tube. The Kane method is used to establish the platform-server two-body dynamics model. Due to the effect of the coupling of the two-bodies, the attitude of the platform is perturbed, causing the server unable to accurately aim at the target satellite while separating the tube. Two velocity pulses are applied to the server through its small rocket engine. The initial pulse occurs at the moment when the server is separating the tube, changing its course to ensure accurate rendezvous with the target satellite; the end pulse occurs at the moment when the server rendezvous to the target satellite, reducing its relative velocity to zero to achieve soft docking. The optimization index is the least energy-efficient, that is to minimize the sum of the squares of the two pulse amplitudes. The paper summarizes it as a nonlinear programming problem. Under the condition that the rendezvous flight time is small compared to the period of the platform orbiting the target satellite, the average angular velocity of the orbiting flight can be regarded as a small parameter, and the canonical perturbation method can be used to obtain the first-order approximate solution of the nonlinear programming. Then the optimizing iteration process is started from the approximate solution as its initial guess. Finally, a numerical simulation verification is carried out.

    • MULTI-OBJECTIVE OPTIMIZATION CONTROL OF TELEOPERATION ROTATING BEAM SYSTEM

      2022, 20(4):74-82. DOI: 10.6052/1672-6553-2021-075

      Abstract (30) HTML (0) PDF 2.47 M (88) Comment (0) Favorites

      Abstract:In this paper, the rotating flexible beam is taken as the research object, and the bilateral control problem for teleoperation systems is investigated via the multiobjective optimization method based on cell mapping. Firstly, the dynamic equation of the rotating flexible beam system in teleoperation system is established. Then, the master controller and slave controller are designed considering the time delays in network transmission and the tracking error signal between the master and slave, and use the Lyapunov stability theory to obtain the conditions of control gains that must be met to ensure the stability of the closedloop control system. Finally, the stability of the system does not mean a good control performance, the multiobjective optimization method based on cell mapping is used to optimize the control design, and the optimal solution set of the control gains satisfying multiple different goals at the same time is obtained. The simulation results show that the obtained control gains can realize the effective tracking between the master and slave beam in the teleoperation system effectively, and the operator can feel the change of the environment of slave system in time.

    • THE FINITE ELEMENT ANALYSIS ON BENDING AND VIBRATION OF THE FLUID-CONVEYING PIPES

      2022, 20(4):83-90. DOI: 10.6052/1672-6553-2021-066

      Abstract (49) HTML (0) PDF 1.18 M (98) Comment (0) Favorites

      Abstract:Based on the Timoshenko beam theory, the finite element equation for bending and vibration of fluid-conveying pipes is derived using the principle of virtual work. The transverse acceleration of fluid is derived using the theorem of acceleration composition. The deflection and slope of the pipe subjected to the combined actions of gravity and fluid under two boundary conditions are obtained, and the influence of fluid velocity on the deflection and slope is analyzed. Under simply supported boundary constraint at both ends the pre-stress effect is transformed to integrate into the strain energy of the pipe, and the relationship between axial pre-stress and bending deflection is studied. The relationships between the first three natural frequencies and the flow velocity of the pipe under the simply supported and cantilever boundary conditions are obtained, and the influence of the axial pre-stress on the natural frequency under the simply supported condition is presented. The results show that under the condition of simply supported boundary, the deflection and slop increase with the increase of fluid velocity, and the deflection and slop decrease with the increase of pre-stress. With the increase of velocity, the first three natural frequencies decrease, while an increase in pre-stress results in higher natural frequencies. For the cantilever boundary condition, the deflection and slope decrease with the increase of fluid velocity, and the first three natural frequencies decrease with increasing flow velocity.

    • FLUID STRUCTURE COUPLING SIMULATION OF DAMPER FOR LOW FREQUENCY VIBRATION CONTROL OF SATELLITE FLEXIBLE APPENDAGES

      2022, 20(4):91-96. DOI: 10.6052/1672-6553-2021-067

      Abstract (48) HTML (0) PDF 1.86 M (124) Comment (0) Favorites

      Abstract:The low frequency vibration of flexible appendage of the satellite is easy to be coupled with the whole satellite, and affect the attitude control effect and imaging performance of the satellite. In this paper, a new type of fluid damper is designed, which can quickly stabilize the low frequency vibration of the flexible appendage by connecting the fluid damper in series between the flexible appendage and the satellite. The specific structural model of the damper are established, and the damping characteristics of the fluid damper are studied by using the finite element analysis method. The variation of damping coefficient with orifice diameter, orifice length and excitation frequency is obtained. The result shows that under low frequency excitation,the damping coefficient decreases with the increase of excitation frequency. The damping coefficient increases first and then decreases with the increase of the diameter and length of the damping hole. The result in this paper can provide useful design reference for the application of this kind of damper in engineering practice.

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