摘要：A screw drive in-pipe robot is promising inspection equipment for small pipes. However, most of the existing screw drive in-pipe robots have problems of motion interference and slipping inside curved or irregular pipes. These problems result from the coupled relations among the steering motion, the motion speed and the load ability of the robot. In order to deal with the problems, the axiomatic design （AD） theory is applied to evaluate and analyze the existing designs. Then an uncoupled con- cept design based on the AD theory is proposed and the complete AD decomposition process is presented. After that, the pro- posed robot based on a tri-axial differential angle modulation mechanism is designed to realize the uncoupled concept. Finally, the uncoupled property is verified in a dynamics simulation system. The simulation results indicate that the mc tion speed, load ability and steering motion of the proposed robot can be adjusted individually compared with the robots taat have inclin- ing-angle-fixed rollers. Owing to the uncoupled design, the proposed robot can mechanically adapt to straight pipes and curved pipes with less roller slipping.

摘要：Marvi et al(Science,2014,vol.346,p.224)concluded a sidewinder rattlesnake increases the body contact length with the sand when granular incline angle *** also claimed the same principle should work on robotic snake *** have evidence to prove that this conclusion is only partial in describing the snake body-sand *** should be three phases that fully represent the snake locomotion behaviors during ascent of sandy slopes,namely lifting,descending,and *** snake body-sand interaction during the descending and ceasing phases helps with the climbing while such interaction during the lifting phase in fact contributes resistance.

摘要：A comprehensive review on bio-inspired fish robots has been done in this article with an enhanced focus on swimming styles,actuators,hydrodynamics,kinematic-dynamic modeling,and *** styles such as body and/or caudal fin and median and/or paired fin and their variants are discussed in *** shows that most fish robots adapt carangiform in body and/or caudal fin type swimming as it gives significant thrust with a maximum speed of 3.7 ms 1 in *** of smart or soft actuators to enhance real-time dynamics was studied from literature,and it was found that the robot built with polymer fiber composite material could reach a speed of 0.6 m s However,dynamic modeling is relatively complex,and material selection needs to be *** numerical and analytical methods in dynamic modeling have been investigated highlighting merits and *** parameter estimation through the data-driven model is widely used in offline,however online estimation of the same need to be *** controllers are frequently used tor navigation and stabilization,which often encounters the linearization problem and hence,can be replaced with the state-of-the-art adaptive and intelligent *** article also summarizes the potential research gaps and future scopes.

摘要：In Magnetic Resonance Imaging(MRI)guided intervention procedures,the flexibility and reliability of the mammary gland fixation device are important indicators for cnsuring the quality of *** paper presents a bionic flexible fixation system for MRI-guided breast biopsy,and establishes a mathematical model of the palm-type curved plate and a breast compression *** bending angle,eccentricity,and tightening stroke of the palm-type curved plate are considered the main influencing *** bending angle and eccentricity of the bionic palm-type curved plate and flexible fingers are optimized,and a prototype of the breast fixation system is *** experimental results show that when the external force is 10 N,the average repetitive accuracy of four lesion points is 0.71 mm,0.60 mm,0.63 mm,and 0.68 mm,*** the pressures are 8 N,10 N,and 12 N,the thickness of the compressed tissue is 76.27 mm,72.8 mm and 68.73 mm,*** has good repetitive accuracy and is compatible with the concept of flexible fixation that reduces the uncomfortable feeling of the human *** propose that by optimizing the flexible tightening mechanism,it is feasible to properly control the external compression force to effectively reduce the compression pain for patients while guaranteeing the tightening reliability in breast biopsy.

摘要：Conventional attractive magnetic force models (proportional to the coil current squared and inversely proportional to the gap squared) cannot simulate the nonlinear responses of magnetic bearings in the presence of electromagnetic losses,flux leakage or saturation of *** this paper,based on results from an experimental set-up designed to study magnetic force,a novel parametric model is presented in the form of a nonlinear polynomial with unknown *** parameters of the proposed model are identified using the weighted residual *** of the model identified were performed by comparing the results in time and frequency *** results show a good correlation between experiments and numerical simulations.

摘要：Highly deformable bodies are essential for numerous types of applications in all sorts of environments. Joint-like structures comprising a ball and socket joint have many degrees of freedom that allow mobility of many biomimetic structures. Recently, soft robots are favored over rigid structures for their highly compliant material, high-deformation properties at low forces, and ability to operate in di fficult environments. However, it is still challenging to fabricate complex designs that satisfy application constraints due to the combined e ffects of material properties, actuation method, and structural geometry on the performance of the soft robot. Therefore, a combination of a rigid joint and a soft body can help achieve modular robots with fully functional body morphology. Yet, the fabrication of soft parts requires extensive molding for complex shapes, which comprises several processes and can be time-consuming. In addition, molded connections between extremely soft materials and hard materials can be critical failing points. In this paper, we present a functionally graded 3D-printed joint-like structure actuated by novel contractile actuators. Functionally graded materials (FGMs) via 3D printing allow for extensive material property enhancement and control which warrant tunable functionalities of the system. The 3D-printed structure is made of 3 rigid ball and socket joints connected in series and actuated by integrating twisted and coiled polymer fishing line ( TCPFL) actuators, which are con fined in the FGM accordion-shaped channels. The implementation of the untethered T CPFL actuation system can be highly bene ficial for deployment in environments that require low vibrations and silent actuation. The fishing line TCP actuators produce an actuation strain up to 40% and bend the joint up to 40° in any direction. The T CPFL can be actuated individually or as a group to control the bending trajectory of the modular joint, which is bene ficial when deployed i

摘要：This article introduces the working principles of a spacecraft hatch including its operating process and moving trajectory. On this basis, an operating mechanism is designed to execute automatic open and close action of the hatch and measure the operating torques. Analysis on the mechanism＇s configuration and topological structure of each phase of movement proves that it is a typical variable freedom mechanism. The mechanism manipulates the hatch in accordance with the moving trajectory requirements through configuration transformation. Kinematic analysis and simulation of some typical configurations show that the velocity differences among mechanism components themselves and the components and their abutting components could exert influences on its working stability during configuration transformation. To solve the problem, stability conditions of configuration transformation are proposed. Appropriate control models are established for the output velocity curves of the driving servo motor and solved based on the stability conditions and rules of movement. Results from another simulation demonstrate that the proposed control models ensure smooth configuration transform and stable operation.

摘要：Miniature devices comprising stimulus-responsive hydrogels with high environmental adaptability are now considered competitive candidates in the fields of biomedicine,precise sensors,and tunable *** and advanced fabricationmethods are critical formaximizing the application capabilities ofminiature ***-based three-dimensional(3D)printing technology offers the advantages of a wide range of applicable materials,high processing accuracy,and strong 3D fabrication capability,which is suitable for the development of miniature devices with various *** paper summarizes and highlights the recent advances in light-based 3D-printed miniaturized devices,with a focus on the latest breakthroughs in lightbased fabrication technologies,smart stimulus-responsive hydrogels,and tunable miniature devices for the fields of miniature cargo manipulation,targeted drug and cell delivery,active scaffolds,environmental sensing,and optical ***,the challenges in the transition of tunable miniaturized devices from the laboratory to practical engineering applications are *** opportunities that will promote the development of tunable microdevices are elaborated,contributing to their improved understanding of these miniature devices and further realizing their practical applications in various fields.

摘要：Cycling is an eco-friendly method of transport and recreation. With the intent of reducing the energy cost of cycling without providing an additional energy source, we have proposed the use of a torsion spring for knee-extension support. We developed an exoskeleton prototype using a crossing four-bar mechanism as a knee joint with an embedded torsion spring. This study evaluates the passive knee exoskeleton using constant-power cycling tests performed by eight healthy male participants. We recorded the surface electromyography over the rectus femoris muscles of both legs, while the participants cycled at 200 and 225 W on a trainer with the developed wheel-accelerating system. We then analyzed these data in time-frequency via a continuous wavelet transform. At the same cycling speed and leg cadence, the median power spectral frequency of the electromyography increases with cycling load. At the same cycling load, the median power spectral frequency decreases when cycling with the exoskeleton. Quadriceps activity can be relieved despite the exoskeleton consuming no electrical energy and not delivering net-positive mechanical work. This fundamental can be applied to the further development of wearable devices for cycling assistance.

摘要：The present work focused on the application of innovative damping technologies in order to improve railway vehicle performances in terms of dynamic stability and comfort. As a benchmark case-study, the secondary sus- pension stage was selected and different control techniques were investigated, such as skyhook, dynamic compensation, and sliding mode control. The final aim was to investigate which control schemes are suitable for optimal exploitation of the non-linear behavior of the actuators. The performance improvement achieved by adoption of the semi-active dampers on a standard high-speed train was evaluated in terms of passenger comfort. Different control strategies have been investigated by comparing a simple SISO （single input single output） regulator based on the skyhook damper ap- proach with a centralized regulator. The centralized regulator allows for the estimation of a near optimal set of control forces that minimize car-body accelerations with respect to constraints imposed by limited performance of semi-active actuators. Simulation results show that best results is obtained using a mixed approach that considers the simultaneous applications of model based and feedback compensation control terms.