Modes Of Motion Research Articles

Technological State and Optimization Analysis of High-Rise Glass Curtain Wall Cleaning Robots

Abstract. With the proliferation of high-rise buildings in urban areas, glass curtain walls are widely used due to their excellent light transmittance and modern appearance. However, these glass curtain walls are prone to accumulating dust, rain stains, and other dirt during use, affecting their aesthetics and transparency, thus requiring regular cleaning. Traditional manual cleaning methods are inefficient and pose significant safety risks. Consequently, high-rise glass curtain wall cleaning robot technology has become a research hotspot. This paper reviews the current research status of high-rise glass curtain wall cleaning robots, which provides a detailed analysis of four main adhesion methods (magnetic adhesion, thrust adhesion, vacuum negative pressure adhesion, and bionic adhesion), four main motion modes (legged, wheeled, tracked, and external assistance), and two main cleaning methods (physical and chemical). For path planning, this paper explores the application status and challenges of regular scanning, random walking, sensor feedback dynamic planning, and bionic path planning. Through the evaluation of the advantages and disadvantages of existing technologies, this paper identifies the main issues faced by each technology and proposes optimization strategies for adhesion technology, motion modes, cleaning efficiency, and path planning. Future directions include improvements in intelligence and automation, multifunctional integration, energy efficiency enhancement, and human-machine collaboration. This paper aims to provide a comprehensive technological review and constructive suggestions to advance high-rise glass curtain wall cleaning robot technology.

Basketball player motion detection and motion mode analysis based on biomechanical sensors

Basketball player motion detection and analysis are crucial for optimizing performance and preventing injuries. Traditional methods often rely on visual observation and video analysis, lacking precision and real-time feedback. In this study, a unique novel Intelligent Bayesian tuned-augmented Support Vector Machine (IB-ASVM) was proposed for predicting basketball players’ motion modes and performance analysis using the biomechanical sensor data. Advancements in biomechanical sensors such as accelerometers, gyroscopes, and force sensors are deployed into ESP32 to build a player’s wearable gadget. This gadget provides dynamic players with real-time sensing data. Data are transmitted to the cloud via Wi-Fi 7.0 for motion analysis and this model is stimulated using Arduino IDE. The Kalman Filter reduces noise and smoothens sensor data such as acceleration, and angular velocity. Then, the filtered data is employed in the Discrete Wavelet Transform (DWT) to capture time-frequency characteristics of motion signals, making it ideal for extracting relevant features. The featured data are utilized in the ASVM model to classify and detect the motion modes of the basketball players via IB optimization. The Tensor Flow software is used to implement the IB-ASVM model. The result demonstrates that IB-ASVM most accurately predicts the jump shot, layup, dribbling, running, pivoting, passing, free throw, and motion states of the basketball players. The IB-ASVM model accurately classifies basketball motion states using biomechanical sensor data, enhancing performance optimization and injury prevention through precise motion detection.

Type Synthesis of a Novel Class of One-DOF Multi-Mode Parallel Mechanisms

Abstract Multi-mode parallel mechanisms (PMs) are a class of reconfigurable mechanisms that can switch between different operation modes without the need for disconnection and reassembly. Although a number of multi-DOF multi-mode PMs have been presented in the literature, very few 1-DOF multi-mode PMs have been proposed. This paper deals with the type synthesis of a novel class of 1-DOF multi-mode PMs, which have one 1-DOF translation mode and at least one 1-DOF planar motion mode, using a construction method by leveraging symmetry of mechanisms and merging two multi-mode mechanisms. By inserting a revolute (R) joint into Sarrus-6R like six-joint mechanisms, 1-DOF two-mode two-legged PMs, which are composed of a moving platform and a base connected by one three-joint leg and one four-joint leg, are constructed first. From each 1-DOF two-mode two-legged PM, one can construct a 1-DOF two-mode three-legged PM by adding a third four-joint leg which is the mirror image of the four-joint leg about the plane of motion of the three-joint leg. Subsequently, 1-DOF three- and four-mode three-legged PMs are constructed by merging two 1-DOF multi-mode three-legged PMs. The instantaneous DOF of the above multi-mode PMs in a transition configuration is analyzed using screw theory. This work complements the existing approaches to the type synthesis of multi-mode PMs and hybrid reconfigurable mechanisms.

Investigation of liquid sloshing characteristics in tanks using an OpenFOAM solver with arbitrary excitation

A multiphase flow solver with mesh motion is typically used for simulations of liquid sloshing in containers, such as those in spacecraft, aircraft, and ships. The mode of the mesh motion should be predefined by functions, which is difficult for a sustained and arbitrary motion. In the present work, a general solver without mesh motion for liquid sloshing in tanks is proposed, based on the interFoam solver in OpenFOAM, by tracking the free surface using the volume of fluid method. An arbitrary excitation loading algorithm is implemented for automatically loading the three-dimensional arbitrary acceleration data. Moreover, the energy equation with phase change is also newly implemented in this solver so that the heat and mass transfer can be evaluated for cryogenic fuels during sloshing. In this way, arbitrary external excitations can be directly imported for any arbitrary sloshing case, and the characteristics of liquid sloshing and oscillation forces can be directly simulated without mesh motion. The solver is validated using different cases, and the influence of sloshing on the mass transfer rate and the effect of the baffle on the liquid sloshing characteristics are investigated. The results indicate that the solver can be easily applied to engineering problems involving liquid sloshing.

Dynamic visualization study of in situ cleaning of polystyrene microparticles off silicon wafer surface

With the improvement of chip performance, the requirements for cleaning the surface of silicon wafers are becoming higher. However, due to equipment and technology, it is difficult to observe the complex motion processes of particles at the microscopic scale. In this paper, an in situ dynamic visualization experiment on the cleaning of Polystyrene Latex (PSL) on the surface of silicon wafers is carried out by using a high-speed camera and image processing software. The mechanical behavior of PSL particles in fluid was investigated on a microscopic scale, and the trajectory and force of the polystyrene particles on the surface of the wafers were visualized, which provided a new perspective for understanding the complex cleaning process. Theoretical models were developed to explain the motion characteristics of the particles by calculating parameters such as van der Waals force, surface tension, and trailing force, and these models provide a theoretical basis for optimizing the cleaning process. There are four particle motion modes in the fluid: (1) interface capture, where the particles on the surface of silicon wafer are trapped by gas–liquid interface under surface tension; (2) particle collision, where the particles captured by the water film collide with the particles on the wafer surface to make the latter leave the silicon wafer; (3) jump attachment, where the particles jump and attach to the surface of the particle group under the action of lift; and (4) wall surface movement, where the particles start up under the action of water flow and then leave the silicon wafer quickly.

Design and Implementation of Small Modular Amphibious Robot System

Various marine engineering facilities have been eroded by marine organisms and wind waves for a long time, resulting in different types of damage to the surface of marine engineering facilities, such as the pile legs of offshore platforms. Therefore, in order to carry out safety inspections and other work on marine engineering facilities, a small amphibious robot structure system and a set of control systems adapted to it are independently developed. Various problems such as the modular design of the structure, composite motion mode, adsorption stability, wall adaptability of the crawling mode, and flaw localization have been solved by means of three-dimensional modeling, mechanical analysis, simulation, and electronic design. At the same time, a set of control systems including hardware and software is developed for the amphibious robot. In order to improve the stability and efficiency of the amphibious robot working underwater, a sliding mode control algorithm based on the exponential reaching law and saturation function is designed. For the fixed depth and fixed heading control functions, the sliding mode control algorithm and the PID control algorithm are simulated and compared. Finally, several types of experiments are carried out for the amphibious robot. The simulation and experimental results show that all the functions of the amphibious robot meet work requirements, such as the motion performance of the composite motion mode. Compared with the PID control algorithm, the sliding mode control algorithm has a faster response speed and better stability, which is conducive to the efficient and stable work of the amphibious robot underwater.

The Effects of Inhibitor Chivosazole A on Actin Interacting with Profilin: A Theoretical Study

AbstractActin is highly conserved and contributes to numerous cellular activities. Profilin, one of actin binding proteins, promotes the exchange rate of nucleotide of actin, which leads to a fast elongation of actin filament. To slow down the elongation of filament, chivosazole A (ChivoA) is developed as an inhibitor of blocking actin‐profilin interaction. Intriguingly, known from the solved crystal structure, ChivoA does not bind on the interface between actin and profilin. Here, molecular dynamics (MD) simulation is used to study the possible mechanism how ChivoA inhibits actin‐profilin interaction. First, principal component analysis and representative structures comparisons reveal that the conformation of ChivoA‐bound actin is restrained at a closed state, whereas a trend toward an open state is found in profilin‐bound actin. Then, Peptide Gaussian accelerated MD shows that ChivoA limits the ability of the DNase I binding loop (D‐loop) swings and enlarges a distance between two major profilin binding regions. On the contrary, the distance between these two regions of profilin‐bound actin decreases in a clamp‐like motion mode. Finally, binding energies are calculated by molecular mechanics/poisson‐boltzmann surface area method and display that the ChivoA‐bound actin is less favorable for profilin binding.

Specificity of manifestation of nonlinearities for angular oscillations of the reservoir with liquid.

Theproblemabouttransient modes of motion of acylindricalreservoirwiththeliquidwithafreesurfaceon a pendulum suspension under short-time moment pulse applies to reservoir walls is under consideration. The problem is considered in nonlinear combined statement. It was ascertained that manifestation of internal mechanisms of nonlinear interaction between normal modes of oscillations of a liquid differs considerably from the case of harmonic moment disturbance on the resonant frequency. For advanced studying the nature of these differences we study problems about harmonic disturbance of oscillations for the system under the moment with a frequency, which is not resonant and immediately resonant disturbance.

Prediction of TBM cutter wear in heterogeneous ground under high ambient pressure

To prevent tunnel face collapse in heterogeneous ground, the applied face pressure in the excavation chamber can be increased to stabilise the tunnel face, which may hinder cutter rotation during tunnel boring machine (TBM) tunnelling. This study proposes a TBM cutter wear prediction model that considers the impact of the variation in the cutter normal force on the cutterhead owing to the high applied face pressure and low penetration rate. First, the cutter motion mode in heterogeneous ground is investigated. The cutter is found to slide when cutting soft rock based on an analysis of the field data. The evolution process of the cutter wear morphology under heterogeneous ground conditions is summarised. A method for calculating the cutter normal force when the cutter slides on the tunnel face is proposed by referring to the cutting mechanism of the drag bits. The cutter hardness is measured on-site using a portable hardness tester. A semi-empirical model considering the variation in the cutter normal force on the cutterhead is proposed to predict the cutter wear in heterogeneous ground. Wear prediction is compared with other predictive models and field data for validation, and the discrepancies between the different models are discussed. The results show that the proposed model is effective for predicting TBM cutter wear under complex geological conditions.

Long range juxtacrine signalling through cadherin for collective cell orientation

Many life phenomena, such as development, morphogenesis, tissue remodelling, and wound healing, are often driven by orderly and directional migration of collective cells. However, when cells are randomly oriented or localized disorder exists in orderly oriented collective cells, cell migration cannot occur in an orderly manner although various motion modes such as global rotation and local swirling and/or various motion patterns such as radial pattern and chiral pattern often occur. Therefore, it is important to control cell orientation to ensure the orderly migration of collective cells. Here, we show that it is not force transmission, but juxtacrine signalling through cadherin that plays a critical role in the orientation of collective cells. Surprisingly, juxtacrine signalling for cell orientation reached cells on a plastic dish that were not directly subjected to mechanical stimulation, up to 7 mm away from the actuator. The present study suggests that even weak mechanical stimulation is transmitted in a long range without force transmission through juxtacrine signalling. The long range juxtacrine signalling might play an important role in various life phenomena. Statement of SignificanceJuxtacrine signalling is direct cell-cell contact-dependent signalling, which plays a crucial role in cell behaviors such as mechanosensing, mechanotransduction and collective cell behaviors, however, there is not enough understanding about juxtacrine signalling. The present study has demonstrated that juxtacrine signalling for collective cell orientation is transmitted over a long range through cadherin. To the best of our knowledge, this is the first report of long range juxtacrine signalling. This finding may lead to the elucidation of various life phenomena such as development, morphogenesis, tissue remodelling, and wound healing.

Scalable Architecture for Trapped-Ion Quantum Computing Using rf Traps and Dynamic Optical Potentials

Qubits based on ions trapped in linear radio-frequency traps form a successful platform for quantum computing, due to their high fidelity of operations, all-to-all connectivity, and degree of local control. In principle, there is no fundamental limit to the number of ion-based qubits that can be confined in a single 1D register. However, in practice, there are two main issues associated with long trapped-ion crystals, that stem from the “softening” of their modes of motion, upon scaling up: high heating rates of the ions’ motion and a dense motional spectrum; both impede the performance of high-fidelity qubit operations. Here, we propose a holistic, scalable architecture for quantum computing with large ion crystals that overcomes these issues. Our method relies on dynamically operated optical potentials that instantaneously segment the ion crystal into cells of a manageable size. We show that these cells behave as nearly independent quantum registers, allowing for parallel entangling gates on all cells. The ability to reconfigure the optical potentials guarantees connectivity across the full ion crystal and also enables efficient midcircuit measurements. We study the implementation of large-scale parallel multiqubit entangling gates that operate simultaneously on all cells and present a protocol to compensate for crosstalk errors, enabling full-scale usage of an extensively large register. We illustrate that this architecture is advantageous both for fault-tolerant digital quantum computation and for analog quantum simulations. Published by the American Physical Society 2024

Experimental Analysis of Shale Cuttings Migration in Horizontal Wells

The extraction of shale gas via horizontal drilling presents considerable challenges, primarily due to the accumulation of cuttings within the annular space, resulting in increased friction, torque, and potential drilling complications. To address this issue, the study proposes an experimental setup aimed at simulating cuttings transport under various operational conditions, with a particular emphasis on gas wells. The methodology encompasses the modulation of the drilling fluid flow rate and the drill’s rotational speed to examine the transport velocity of cuttings. Furthermore, the study analyzes the impact of annular eccentricity on return volume, transport time, and cuttings bed height. Critical initiation velocities for cuttings across different motion modes were also determined, and theoretical calculations were compared with empirical data. The findings indicate that an increased flow rate of drilling fluid and higher rotation speed substantially improve the transport of cuttings, thereby minimizing bed formation, whereas increased eccentricity hinders this process. The results revealed that the theoretical model showed a greater overestimation of the start-up velocity for spherical particles, with average errors ranging from 15.50% to 17.56%. In contrast, the model exhibited better accuracy for non-spherical (flaky) particles, with errors between 8.63% and 9.61%. Under non-rotating conditions, the average error of the model was approximately 8.32%, while the introduction of drill tool rotation increased the average error to 11.94%. These results have the potential to optimize operational parameters in shale gas well drilling and may contribute to the development of specialized borehole purification tools.

On Trade-Off Relationship between Static and Dynamic Lateral Stabilities of Articulated Heavy Vehicles

Articulated heavy vehicles exhibit poor lateral stability, which may lead to unstable motion modes, e.g., trailer-sway and jackknifing, causing severe accidents. Varying relevant vehicle parameters improves the static stability but degrades the dynamic stability. The past studies focused either on the static or dynamic stability alone. However, little attention has been paid to exploring the trade-off between the static and dynamic stabilities. To gain design insights for active safety systems for AHVs, this article studies this trade-off systematically. To this end, a systematic method is proposed to conduct the linear stability and trade-off analysis. To implement and demonstrate the proposed method, a linear three-degrees-of-freedom yaw-plane model is generated to represent a tractor/semi-trailer. A trade-off analysis is conducted considering two tractor rear-axle configurations and three trailer payload arrangements. In each case, simulation is performed in both steady-state and transient testing maneuvers. To validate the linear stability analysis based on the linear yaw-plane model, two nonlinear TruckSim models are introduced, and the corresponding simulation is conducted. Insightful understanding of the trade-off is gained through analyzing the simulation results, and the linear stability analysis will provide valuable guidelines for the design and development of active safety systems for AHVs.

Robo-Matter towards reconfigurable multifunctional smart materials

Maximizing materials utilization efficiency via enhancing their reconfigurability and multifunctionality offers a promising avenue in addressing the global challenges in sustainability. To this end, significant efforts have been made in developing reconfigurable multifunctional smart materials, which can exhibit remarkable behaviors such as morphing and self-healing. However, the difficulty in efficiently manipulating and controlling matter at the building block level with manageable cost and complexity, which is crucial to achieving superior responsiveness to environmental clues and stimuli, has significantly hindered the further development of such smart materials. Here we introduce a concept of Robo-Matter, which can be activated and controlled through external information exchange at the building block level, to enable a high-level of controllability, mutability and versatility for reconfigurable multifunctional smart materials. Using specially designed micro-robot building blocks with symmetry-breaking active motion modes, tunable anisotropic interactions, and interactive coupling with a programmable spatial-temporal dynamic light field, we demonstrate an emergent Robot-Matter duality, which enables a spectrum of desirable behaviors spanning from matter-like properties such as ultra-fast self-assembly and adaptivity, to robot-like properties including active force output, smart healing, smart morphing and infiltration. Our work demonstrates a promising direction for designing next-generation smart materials and large-scale robotic swarms.

Design, Analysis, and Optimization Testing of a Novel Modular Walking Device for Pipeline Robots

This article investigates the limitations associated with traditional wheel-type pipeline walking devices, which are characterized by a single movement mode and an inability to navigate complex or irregular pipeline structures. A modular walking device (MWD) designed for pipeline robots was developed utilizing structural and mechanical analysis techniques. The reliability of the mechanical analysis was validated through single-factor dynamic testing. To analyze and optimize the factors influencing the maneuverability and obstacle-crossing capabilities of the MWD, a three-factor, three-level orthogonal testing method was utilized. The factors examined included the rotational speed of the walking wheel (RS), the pre-tightening force of the wheel brackets (PF), and the height of the annular obstacle (OH). The evaluation metrics used were the slip rate and passability. The results indicated that a parameter combination of RS at 70 rpm, PF at 30 N, and OH at 10 mm produced a slip rate of 11.6% ± 1.5%. During the obstacle traversal process, the remainder of the device maintained a safe distance from the obstacles, with only the walking wheel making contact. The verification testing also confirmed that the MWD is capable of executing three distinct modes of motion: rectilinear, rotational, and helical. The MWD designed and developed in this study can switch between multiple motion modes and successfully overcome obstacles within 15 mm, providing a new equipment for universities to enhance mechanized pipeline detection technology.

Optically Responsive Hydrogel with Rapid Deformation for Motion Regulation of Magnetic Actuators.

Optically and magnetically responsive soft actuators are gaining attention for their noncontact actuation, flexibility, and remote control capabilities. However, they face challenges in rapidly switching motion postures and modes, which limits their performance in complex environments. We developed bilayer hydrogel actuators based on poly(N-isopropylacrylamide) (PNIPAm) using an ice-templating method combined with free radical polymerization. This approach results in the formation of large, interconnected pores within the hydrogel. Under near-infrared light (27 W/cm2), the actuation speed of the actuator reached 38.5°/s, with complete recovery to the original shape 8 s after light cessation. In addition, the reversible changes in stiffness and volume enable the actuators to lock and dynamically adjust their magnetization curve, allowing for the decoupling of deformation and movement as well as the regulation of motion postures and modes. This work opens new pathways for multigait robots and shows promising applications in environmental monitoring and underwater exploration.

A linkage-type self-adaptive deformable tracked mechanism based on the six-bar mechanism

Abstract. In order to design a self-adaptive tracked mechanism that can passively adjust according to the height of different obstacles to improve its obstacle-crossing performance, this paper proposes a linkage-type self-adaptive deformable tracked mechanism. The mechanism based on the planar six-bar mechanism is proposed, and its motion modes and obstacle-crossing capabilities are analyzed. Firstly, based on the characteristics of self-adaptive deformation and the planar six-bar mechanism, a deformable single-degree-of-freedom (DOF) multi-loop mechanism is designed by limiting the DOF and adjusting the link lengths, and subsequently, a linkage-type self-adaptive deformable tracked mechanism module is designed according to the multi-loop mechanism. Secondly, the movement characteristics of the deformable tracked mechanism module are analyzed, and it is obtained that the tracked mechanism has two modes of movement: forward and reverse. These modes include deformable tracked-type obstacle crossing and rocker-arm-type obstacle crossing, respectively. Additionally, it is also obtained that this mechanism is capable of climbing up and descending down slopes. Finally, a prototype model is designed for experimental verification to verify the correctness of the theoretical analysis of the linkage-type self-adaptive deformable tracked mechanism and the feasibility of the obstacle-crossing modes. The results indicate that the linkage-type self-adaptive deformable tracked mechanism is capable of various obstacle-crossing modes, including both forward and reverse movements. These modes encompass the traditional tracked type, the deformable tracked type, and the rocker-arm type, as well as the ability to climb up and descend down slopes. This type of mechanism demonstrates excellent terrain adaptability and is capable of overcoming obstacles, allowing it to traverse some soft and rugged terrain. Consequently, it holds certain application potential.

Principle and pressure loss experiment of electro-hydraulic slide-rotary direction valve in single-pump and multi-motor hydraulic system

To better realize direction control of the single-pump double-motor hydraulic system and simplify the system, structure and principle of a six-position six-way direction control valve was proposed, which the valve spool has two motion modes: sliding and rotating. Using this valve, the inner and outer motors can work independently and simultaneously. The pressure loss of the valve was tested by building a transmission system, and the experiment results were compared with theoretical analysis. The results show that the performance of the valve working in left and right positions is better than that in meso-position, and the maximum pressure loss occurred in meso-position. Under the rated flow, the maximum pressure loss is 0.331 MPa. Then the characteristic curve of flow-pressure loss and the relationship of pressure loss among oil ports are obtained. In the same conditions, except that the oil inlet pressure loss in the meso-position is greater than the oil outlet pressure loss, the oil inlet pressure loss in the left and right positions are less than the oil outlet pressure loss, the pressure loss in the forward position is less than the pressure loss in the reverse position. The experiment verifies the correctness and feasibility of the structure and principle.

Study on the motion characteristics of Janus based on the squirmer model in the flow

The motion characteristics of Janus in the flow are studied numerically using the lattice Boltzmann method based on the squirmer model. The effects of velocity ratio J on the right and left hemisphere surface of Janus, particle Reynolds number Rep, flow Reynolds number Rec, initial orientation angle φ0 on Janus trajectory, and lateral equilibrium position yeq/H are analyzed. The results showed that, for the motion of Janus in stationary power-law fluids in a channel, Janus moves randomly in a small space in shear-thickening fluids when Rep is low and exhibits three motion modes at Rep = 5. The larger the J value, the easier it is for Janus to reach yeq/H. The higher the Rep, the closer the yeq/H is to the lower wall. In shear-thinning fluids, the motion of Janus exhibits significant randomness at Rep = 0.5 and 1, reaches the same yeq/H at Rep = 2 and 3, and tends toward yeq/H near the centerline and along the upper wall, respectively, at Rep = 4 and 5. For the motion of Janus particles in a channel flow of power-law fluids, in shear-thinning fluids, no matter what value J is, Janus reaches yeq/H on the centerline. The lower the Rep, the closer the yeq/H is to the wall. Two particles move toward yeq/H when Rep ≥ 1. The higher the Rep, the closer the yeq/H is to the centerline. The two particles will exhibit the upstream mode at Rep = 2. Two particles eventually reach yeq/H at different Rec. When φ0 > 0°, the two particles first eventually tend toward yeq/H = 0.2 and 0.8. When the value of φ0 is negative, the larger the absolute value of φ0 and higher the Rep, the more likely particles are to exhibit upstream mode.

Analysis of motion performance and motion mode recognition in filament propulsion

Abstract In this study, the full free motion of the filament in vortex structures is numerically simulated, and the influence of model parameters and horizontal position on the propulsion efficiency of the filament is investigated. With the “data + physics” approach with the immersed boundary method and Random Forest (RF) method, an RF model is initially employed to screen 189 sets of numerical experiments using a minimal amount of flow field physical data to select experimental groups capable of generating vortex bands. The selected experimental groups are then used to complete numerical experiments, followed by the re-introduction of a minimal amount of data and the use of the RF model to identify the motion modes of the filament. The experimental results indicate that the stretching coefficient of the filament has a negative effect on the thrust coefficient when the filament is in the vortex. The thrust of the filament decreases with increasing horizontal distance. The RF model demonstrates excellent identification capabilities, correctly classifying the vortex street structure with only three sets of data from three test points, achieving a high accuracy rate of 95% in identifying the motion modes of the filament.