2018年, 第31卷, 第1期 
刊出日期:2018-02-16
  

  • 全选
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    Mechanism and Robotics
  • Shan Chai, Xiang-Fei Ji, Li-Jun Li, Ming Guo
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 1-1. https://doi.org/10.1186/s10033-018-0219-4
    摘要 ( ) PDF全文 ( )   可视化   收藏
    Polynomial-basis response surface method has some shortcomings for truss structures in structural optimization, concluding the low ftting accuracy and the great computational efort. Based on the theory of approximation, a response surface method based on Multivariate Rational Function basis (MRRSM) is proposed. In order to further reduce the computational workload of MRRSM, focusing on the law between the cross-sectional area and the nodal displacements of truss structure, a conjecture that the determinant of the stifness matrix and the corresponding elements of adjoint matrix involved in displacement determination are polynomials with the same order as their respective matrices, each term of which is the product of cross-sectional areas, is proposed. The conjecture is proved theoretically for statically determinate truss structure, and is shown corrected by a large number of statically indeterminate truss structures. The theoretical analysis and a large number of numerical examples show that MRRSM has a high ftting accuracy and less computational efort. Efciency of the structural optimization of truss structures would be enhanced.
  • Intelligent Manufacturing Technology
  • Jun Huang, Yi-Chao Zhu, Wei-Dong Shi, Jian-Hui Zhang
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 2-2. https://doi.org/10.1186/s10033-018-0217-6
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    Valve piezoelectric pumps usually have larger fow rate than that of valveless ones. However, the traditional cantilever valve easily induces stress concentration which impacts the reliability of pumps. Therefore, a cymbal-shaped slotted check valve is proposed to be applied in a piezoelectric pump in order to reduce the stress concentration of the valve and thus improve the reliability of the piezoelectric pump. The structure and working principle of the piezoelectric pump are analyzed; the stress analysis of the cymbal-shaped slotted valve diaphragm is conducted. In addition, fnite element software is employed to analyze the diference of the Von-Mises stress between the cymbal-shaped slotted diaphragm and the slotted fat diaphragm. The simulation results show that, the Von-Mises stress of cymbal-shaped slotted diaphragm is smaller than that of the slotted fat one. Furthermore, the cymbal-shaped slotted valve piezoelectric pump is also fabricated, and fow rate experiment is performed. The experimental results indicate that the fow rate of piezoelectric pump working in low frequencies (0 Hz < f < 50 Hz) is larger than that working in high frequencies (200 Hz < f < 2000 Hz). When driven at voltage of 160 V and frequency of 5 Hz, the pump reaches its maximum fow rate of 6.6 g/min. The experimental results validate the feasibility of the cymbal-shaped slotted check valve. This research can efectively solve the problem of stress concentration of valve piezoelectric pumps and is helpful for improving the reliability of them.
  • Xiang-Heng Fu, Mao-Lin Cai, Yi-Xuan Wang, Yan Shi
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 3-3. https://doi.org/10.1186/s10033-018-0220-y
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    Pneumatic-hydraulic transmission has been developed for years. However, its dynamic properties are not good enough for application. In this paper, in order to increase the output characteristics, a late-model air-powered vehicle using expansion energy is proposed which can boost energy through a pneumatic-hydraulic transmission. The dynamic characteristics of the air-powered vehicle is modeled and verifed by conducting experiment. In addition, the infuence of the key parameters of the air-powered vehicle is researched for the optimization of the system performance. Through the results, the author got the conclusion that, frstly, comparison of the results of model and experiment proves the built model to be efective; secondly, input air pressure should be set according to the request of the practical loads, and range of 0.65 to 0.75 MPa can be chosen; thirdly, as a key structure parameter of the air-powered vehicle, ratio of the areas is considered to be set to approximate 8; what's more, a bigger orifce with a limit will promote the system dynamic characteristic property, and the limit is about 3.5 mm; last but not the least, not too farther position of the rings will increase the quality of output dynamic characteristics. This paper can be a reference for system design of air-powered vehicle and dynamic improvement.
  • Li-Ming Wang, Yi-Min Shao
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 4-4. https://doi.org/10.1186/s10033-018-0202-0
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    During the condition monitoring of a planetary gearbox, features are extracted from raw data for a fault diagnosis. However, diferent features have diferent sensitivity for identifying diferent fault types, and thus, the selection of a sensitive feature subset from an entire feature set and retaining as much of the class discriminatory information as possible has a directly efect on the accuracy of the classifcation results. In this paper, an improved hybrid feature selection technique (IHFST) that combines a distance evaluation technique (DET), Pearson's correlation analysis, and an ad hoc technique is proposed. In IHFST, a temporary feature subset without irrelevant features is frst selected according to the distance evaluation criterion of DET, and the Pearson's correlation analysis and ad hoc technique are then employed to fnd and remove redundant features in the temporary feature subset, respectively, and hence, a sensitive feature subset without irrelevant or redundant features is selected from the entire feature set. Further, the k-means clustering method is applied to classify the diferent kinds of health conditions. The efectiveness of the proposed method was validated through several experiments carried out on a planetary gearbox with incipient cracks seeded in the tooth root of the sun gear, planet gear, and ring gear. The results show that the proposed method can successfully distinguish the diferent health conditions of a planetary gearbox, and achieves a better classifcation performance than other methods. This study proposes a sensitive feature subset selection method that achieves an obvious improvement in terms of the accuracy of the fault classifcation.
  • Ya-Wei Hu, Hong-Chao Zhang, Shu-Jie Liu, Hui-Tian Lu
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 5-5. https://doi.org/10.1186/s10033-018-0205-x
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    Online assessment of remaining useful life (RUL) of a system or device has been widely studied for performance reliability, production safety, system conditional maintenance, and decision in remanufacturing engineering. However, there is no consistency framework to solve the RUL recursive estimation for the complex degenerate systems/device. In this paper, state space model (SSM) with Bayesian online estimation expounded from Markov chain Monte Carlo (MCMC) to Sequential Monte Carlo (SMC) algorithm is presented in order to derive the optimal Bayesian estimation. In the context of nonlinear & non-Gaussian dynamic systems, SMC (also named particle flter, PF) is quite capable of performing fltering and RUL assessment recursively. The underlying deterioration of a system/device is seen as a stochastic process with continuous, nonreversible degrading. The state of the deterioration tendency is fltered and predicted with updating observations through the SMC procedure. The corresponding remaining useful life of the system/device is estimated based on the state degradation and a predefned threshold of the failure with two-sided criterion. The paper presents an application on a milling machine for cutter tool RUL assessment by applying the above proposed methodology. The example shows the promising results and the efectiveness of SSM and SMC online assessment of RUL.
  • Yu-Feng Li, Yu-Lin Wang, Yan He, Yan Wang, Shen-Long Lin
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 6-6. https://doi.org/10.1186/s10033-018-0213-x
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    CNC machining systems are inevitably confronted with frequent changes in energy behaviors because they are widely used to perform various machining tasks. It is a challenge to understand and analyze the fexible energy behaviors in CNC machining systems. A method to model fexible energy behaviors in CNC machining systems based on hierarchical objected-oriented Petri net (HOONet) is proposed. The structure of the HOONet is constructed of a high-level model and detail models. The former is used to model operational states for CNC machining systems, and the latter is used to analyze the component models for operational states. The machining parameters having great impacts on energy behaviors in CNC machining systems are declared with the data dictionary in HOONet models. A case study based on a CNC lathe is presented to demonstrate the proposed modeling method. The results show that it is efective for modeling fexible energy behaviors and providing a fne-grained description to quantitatively analyze the energy consumption of CNC machining systems.
  • Yan-Ding Qin, Xin Zhao, Bijan Shirinzadeh, Yan-Ling Tian, Da-Wei Zhang
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 7-7. https://doi.org/10.1186/s10033-018-0211-z
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    Flexure-based mechanisms are widely utilized in nano manipulations. The closed-form statics and dynamics modeling is difcult due to the complex topologies, the inevitable compliance of levers, the Hertzian contact interface, etc. This paper presents the closed-form modeling of an XY nano-manipulator consisting of statically indeterminate symmetric (SIS) structures using leaf and circular fexure hinges. Theoretical analysis reveals that the lever's compliance, the contact stifness, and the load mass have signifcant infuence on the static and dynamic performances of the system. Experiments are conducted to verify the efectiveness of the established models. If no piezoelectric actuator (PEA) is installed, the infuence of the contact stifness can be eliminated. Experimental results show that the estimation error on the output stifness and frst natural frequency can reach 2% and 1.7%, respectively. If PEAs are installed, the contact stifness shows up in the models. As no efective method is currently available to measure or estimate the contact stifness, it is impossible to precisely estimate the performance of the overall system. In this case, the established closed-form models can be utilized to calculate the bounds of the performance. The established closed-form models are widely applicable in the design and optimization of planar fexure-based mechanisms.
  • Guo-Da Chen, Ya-Zhou Sun, Fei-Hu Zhang, Li-Hua Lu, Wan-Qun Chen, Nan Yu
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 8-8. https://doi.org/10.1186/s10033-018-0208-7
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    Ultra-precision machine tool is the most important physical tool to machining the workpiece with the frequency domain error requirement, in the design process of which the dynamic accuracy design (DAD) is indispensable and the related research is rarely available. In light of above reasons, a DAD method of ultra-precision machine tool is proposed in this paper, which is based on the frequency domain error allocation. The basic procedure and enabling knowledge of the DAD method is introduced. The application case of DAD method in the ultra-precision fycutting machine tool for KDP crystal machining is described to show the procedure detailedly. In this case, the KDP workpiece surface has the requirements in four diferent spatial frequency bands, and the emphasis for this study is put on the middle-frequency band with the PSD specifcations. The results of the application case basically show the feasibility of the proposed DAD method. The DAD method of ultra-precision machine tool can efectively minimize the technical risk and improve the machining reliability of the designed machine tool. This paper will play an important role in the design and manufacture of new ultra-precision machine tool.
  • Yi-Fan Lu, Hong-Hao Yue, Zong-Quan Deng, Horn-Sen Tzou
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 9-9. https://doi.org/10.1186/s10033-018-0212-y
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    Optical membrane mirrors are promising key components for future space telescopes. Due to their ultra-thin and high fexible properties, the surfaces of these membrane mirrors are susceptible to temperature variations. Therefore adaptive shape control of the mirror is essential to maintain the surface precision and to ensure its working performance. However, researches on modeling and control of membrane mirrors under thermal loads are sparse in open literatures. A 0.2 m diameter scale model of a polyimide membrane mirror is developed in this study. Three Polyvinylidene fuoride (PVDF) patches are laminated on the non-refective side of the membrane mirror to serve as in-plane actuators. A new mathematical model of the piezoelectric actuated membrane mirror in multiple felds, (i.e., thermal, mechanical, and electrical feld) is established, with which dynamic and static behaviors of the mirror can be analyzed. A closed-loop membrane mirror shape control system is set up and a surface shape control method based on an infuence function matrix of the mirror is then investigated. Several experiments including surface displacement tracking and thermal deformation alleviation are performed. The deviations range from 15 μm to 20 μm are eliminated within 0.1 s and the residual deformation is controlled to micron level, which demonstrates the efectiveness of the proposed membrane shape control strategy and shows a satisfactory real-time performance. The proposed research provides a technological support and instruction for shape control of optical membrane mirrors.
  • Da-Chun Fu, Fu-Jun Wang, Pei-Jian Zhou, Ruo-Fu Xiao, Zhi-Feng Yao
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 10-10. https://doi.org/10.1186/s10033-018-0203-z
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    Pressure fuctuation may cause high amplitude of vibration of double-suction centrifugal pumps, but the impact of impeller stagger angles is still not well understood. In this paper, pressure fuctuation experiments are carried out for fve impeller confgurations with diferent stagger angles by using the same test rig system. Results show that the stagger angles exert negligible efects on the characteristics of head and efciency. The distributions of pressure fuctuations are relatively uniform along the suction chamber wall, and the maximum pressure fuctuation amplitude is reached near the suction inlet tongue region. The pressure fuctuation characteristics are afected largely by impeller rotation, whose dominant frequencies include impeller rotation frequency and its harmonic frequencies, and half blade passage frequency. The stagger angle exerts a small efect on the pressure fuctuations in the suction chamber while a great efect on the pressure fuctuation in volute casing, especially on the aspect of decreasing the amplitude on blade passage frequency. Among the tested cases, the distribution of pressure fuctuations in the volute becomes more uniform than the other impeller confgurations and the level of pressure fuctuation may be reduced by up to 50% when the impeller stagger angle is close to 24° or 36°. The impeller structure pattern needs to be taken into consideration during the design period, and the halfway staggered impeller is strongly recommended.
  • Mechanism and Robotics
  • Ran Liu, Yan-An Yao, Wan Ding, Xiao-Ping Liu
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 11-11. https://doi.org/10.1186/s10033-018-0215-8
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    Locomotion and manipulation optimization is essential for the performance of tetrahedron-based mobile mechanism. Most of current optimization methods are constrained to the continuous actuated system with limited degree of freedom (DOF), which is infeasible to the optimization of binary control multi-DOF system. A novel optimization method using for the locomotion and manipulation of an 18 DOFs tetrahedron-based mechanism called 5-TET is proposed. The optimization objective is to realize the required locomotion by executing the least number of struts. Binary control strategy is adopted, and forward kinematic and tipping dynamic analyses are performed, respectively. Based on a developed genetic algorithm (GA), the optimal number of alternative struts between two adjacent steps is obtained as 5. Finally, a potential manipulation function is proposed, and the energy consumption comparison between optimal 5-TET and the traditional wheeled robot is carried out. The presented locomotion optimization and manipulation planning enrich the research of tetrahedron-based mechanisms and provide the instruction to the successive locomotion and operation planning of multi-DOF mechanisms.
  • Wei Ye, Qin-Chuan Li, Xin-Xue Chai
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 12-12. https://doi.org/10.1186/s10033-018-0201-1
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    Parallel mechanisms (PMs) having the same motion characteristic with a UP kinematic chain (U denotes a universal joint, and P denotes a prismatic joint) are called UP-equivalent PMs. They can be used in many applications, such as machining and milling. However, the existing UP-equivalent PMs sufer from the disadvantages of strict assembly requirements and limited rotational capability. Type synthesis of UP-equivalent PMs with high rotational capability is presented. The special 2R1T motion is briefy discussed and the fact that the parallel module of the Exechon robot is not a UP-equivalent PM is disclosed. Using the Lie group theory, the kinematic bonds of limb chains and their mechanical generators are presented. Structural conditions for constructing such UP-equivalent PMs are proposed, which results in numerous new architectures of UP-equivalent PMs. The high rotational capability of the synthesized mechanisms is illustrated by an example. The advantages of no strict assembly requirements and high rotational capability of the newly developed PMs will facilitate their applications in the manufacturing industry.
  • Review
  • Wen-Hua Chen, Liang Gao, Jun Pan, Ping Qian, Qing-Chuan He
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 13-13. https://doi.org/10.1186/s10033-018-0206-9
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    Accelerated life test (ALT) is currently the main method of assessing product reliability rapidly, and the design of efcient test plans is a critical step to ensure that ALTs can assess the product reliability accurately, quickly, and economically. With the promotion of the national strategy of civil-military integration, ALT will be widely used in the research and development (R & D) of various types of products, and the ALT plan design theory will face further challenges. To aid engineers in selecting appropriate theories and to stimulate researchers to develop the theories required in engineering, with focus on the demands for theory research that arise from the implementation of ALT, this paper reviews and summarizes the development of ALT plan design theory. The development of the theory and method for planning optimal ALT for location-scale distribution, which is the most applied and mature theory of designing the optimal ALT plan, are described in detail. Taking this as the center of radiation, some problems that ALT now faces, such as the verifcation of the statistical model, limitation of sample size, solutions of resource limits, optimization of the test arrangement, and management of product complexity, are discussed, and the general ideas and methods of solving these problems are analyzed. Suggestions for selecting appropriate ALT plan design theories are proposed, and the urgent solved theory problems and opinions of their solutions are proposed. Based on the principle of convenience for engineers to select appropriate methods according to the problems found in practice, this paper reviews the development of optimal ALT plan design theory by taking the engineering problems arising from the ALT implementation as the main thread, provides guidelines on selecting appropriate theories for engineers, and proposes opinions about the urgent solved theory problems for researchers.
  • Mechanism and Robotics
  • Gui-Min Chen, Larry L.Howell
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 14-14. https://doi.org/10.1186/s10033-018-0214-9
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    There are several design equations available for calculating the torsional compliance and the maximum torsion stress of a rectangular cross-section beam, but most depend on the relative magnitude of the two dimensions of the crosssection (i.e., the thickness and the width). After reviewing the available equations, two thickness-to-width ratio independent equations that are symmetric with respect to the two dimensions are obtained for evaluating the maximum torsion stress of rectangular cross-section beams. Based on the resulting equations, outside lamina emergent torsional joints are analyzed and some useful design insights are obtained. These equations, together with the previous work on symmetric equations for calculating torsional compliance, provide a convenient and efective way for designing and optimizing torsional beams in compliant mechanisms.
  • Da Xi, Feng Gao
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 15-15. https://doi.org/10.1186/s10033-018-0216-7
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    Walking robots use leg structures to overcome obstacles or move on complicated terrains. Most robots of current researches are equipped with legs of simple structure. The specifc design method of walking robot legs is seldom studied. Based on the generalized-function (GF) set theory, a systematic type synthesis process of designing robot legs is introduced. The specifc mobility of robot legs is analyzed to obtain two main leg types as the goal of design. Number synthesis problem is decomposed into two stages, actuation and constraint synthesis by name, corresponding to the combinatorics results of linear Diophantine equations. Additional restrictions are discussed to narrow the search range to propose practical limb expressions and kinematic-pair designs. Finally, all the ffty-one leg structures of four subtypes are carried out, some of which are chosen to make up robot prototypes, demonstrating the validity of the method. This paper proposed a novel type synthesis methodology, which could be used to systematically design various practical robot legs and the derived robots.
  • Review
  • Wei Yuan, Li-Hua Li, Wing-Bun Lee, Chang-Yuen Chan
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 16-16. https://doi.org/10.1186/s10033-018-0204-y
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    Microlens arrays are the key component in the next generation of 3D imaging system, for it exhibits some good optical properties such as extremely large feld of view angles, low aberration and distortion, high temporal resolution and infnite depth of feld. Although many fabrication methods or processes are proposed for manufacturing such precision component, however, those methods still need to be improved. In this review, those fabrication methods are categorized into direct and indirect method and compared in detail. Two main challenges in manufacturing microlens array are identifed:how to obtain a microlens array with good uniformity in a large area and how to produce the microlens array on a curved surface? In order to efectively achieve control of the geometry of a microlens, indirect methods involving the use of 3D molds and replication technologies are suggested. Further development of ultraprecision machining technology is needed to reduce the surface fuctuation by considering the dynamics of machine tool in tool path planning. Finally, the challenges and opportunities of manufacturing microlens array in industry and academic research are discussed and several principle conclusions are drawn.
  • Ocean Engineering Equipment
  • Dong-Yang Xue, Zhi-Liang Wu, Yan-Hui Wang, Shu-Xin Wang
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 17-17. https://doi.org/10.1186/s10033-018-0210-0
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    The formation of hybrid underwater gliders has advantages in sustained ocean observation with high resolution and more adaptation for complicated ocean tasks. However, the current work mostly focused on the traditional gliders and AUVs. The research on control strategy and energy consumption minimization for the hybrid gliders is necessary both in methodology and experiment. A multi-layer coordinate control strategy is developed for the feet of hybrid underwater gliders to control the gliders' motion and formation geometry with optimized energy consumption. The inner layer integrated in the onboard controller and the outer layer integrated in the ground control center or the deck controller are designed. A coordinate control model is proposed based on multibody theory through adoption of artifcial potential felds. Considering the existence of ocean fow, a hybrid motion energy consumption model is constructed and an optimization method is designed to obtain the heading angle, net buoyancy, gliding angle and the rotate speed of screw propeller to minimize the motion energy with consideration of the ocean fow. The feasibility of the coordinate control system and motion optimization method has been verifed both by simulation and sea trials. Simulation results show the regularity of energy consumption with the control variables. The feet of three Petrel-Ⅱ gliders developed by Tianjin University is deployed in the South China Sea. The trajectory error of each glider is less than 2.5 km, the formation shape error between each glider is less than 2 km, and the diference between actual energy consumption and the simulated energy consumption is less than 24% actual energy. The results of simulation and the sea trial prove the feasibility of the proposed coordinate control strategy and energy optimization method. In conclusion, a coordinate control system and a motion optimization method is studied, which can be used for reference in theoretical research and practical feet operation for both the traditional gliders and hybrid gliders.
  • Li-Quan Wang, Zong-Liang Wei, Shao-Ming Yao, Yu Guan, Shao-Kai Li
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 18-18. https://doi.org/10.1186/s10033-018-0209-6
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    Researchers seldom study the optimum design of a mechanical connector for subsea oil-gas pipeline based upon the sealing performance. An optimal design method of a novel subsea pipeline mechanical connector is presented. By analyzing the static metal sealing mechanism, the critical condition of the sealing performance is established for this connector and the formulation method of the contact pressure on the sealing surface is created. By the method the minimum mean contact pressure of the 8.625 inch connector is calculated as 361 MPa, which is the constraint condition in the optimum design of connector. The fnite element model is created in ANSYS Parametric Design Language (APDL) and the structure is optimized by the zero-order method, with variance of contact pressure as the objective function, and mean contact pressures and plastic strains as constraint variables. The optimization shows that variances of contact pressure on two sealing surfaces decrease by 72.41% and 89.33%, respectively, and mean contact pressures increase by 31.18% and 52.84%, respectively. The comparison of the optimal connectors and non-optimal connectors in the water pressure experiments and bending experiments shows that the sealing ability of optimized connectors is much higher than the rated pressure of 4.5 MPa, and the optimal connectors don't leak under the bending moment of 52.2 kN·m. This research provides the formulation to solve contact pressure on the sealing surface and a structure optimization method to design the connectors with various dimensions.
  • Hai Huang, Guo-Cheng Zhang, Ji-Yong Li, Qiang Zhang, Jin-Yu Xu, Hong-De Qin
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 19-19. https://doi.org/10.1186/s10033-018-0218-5
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    Underwater vehicles are being emphasized as highly integrated and intelligent devices for a signifcant number of oceanic operations. However, their precise operation is usually hindered by disturbances from a tether or manipulator because their propellers are unable to realize a stable suspension. A dynamic multi-body model-based adaptive controller was designed to allow the controller of the vehicle to observe and compensate for disturbances from a tether or manipulator. Disturbances, including those from a tether or manipulator, are deduced for the observation of the controller. An analysis of a tether disturbance covers the conditions of the surface, the underwater area, and the vehicle end point. Interactions between the vehicle and manipulator are mainly composed of coupling forces and restoring moments. To verify the robustness of the controller, path-following experiments on a streamlined autonomous underwater vehicle experiencing various disturbances were conducted in Song Hua Lake in China. Furthermore, path-following experiments for a tethered open frame remote operated vehicle were verifed for accurate cruising with a controller and an observer, and vehicle and manipulator coordinate motion control during the simulation and experiments verifed the efectiveness of the controller and observer for underwater operation. This study provides instructions for the control of an underwater vehicle experiencing disturbances from a tether or manipulator.
  • Mechanism and Robotics
  • Qi-Quan Quan, Chong-Bin Chen, Zong-Quan Deng, Jun-Yue Tang, De-Wei Tang
    Chinese Journal of Mechanical Engineering. 2018, 31(1): 20-20. https://doi.org/10.1186/s10033-018-0207-8
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    Drilling and coring, as efective ways to obtain lunar regolith along the longitudinal direction, are widely applied in the lunar sampling feld. Conventionally, modeling of drill-soil interaction was divided into soil cutting and screw conveyance processes, ignoring the diferences in soil mechanical properties between them. To improve the modeling accuracy, a hypothesis that divides the drill-soil interaction into four parts:cuttings screw conveyance, cuttings extruding, cuttings bulldozing, and in situ simulant cutting, is proposed to establish a novel model based on the passive earth pressure theory. An iterative numerical calculation method is developed to predict the drilling loads. A drilling and coring testbed is developed to conduct experimental tests. Drilling experiments indicate that the drilling loads calculated by the proposed model match well the experimental results. The proposed research provides the instructions to adopt a suitable drilling strategy to match the rotary and penetrating motions, to increase the safety and reliability of drilling control in lunar sampling missions.