Kinematic System Research Articles

Monitoring the Subsidence Induced by Salt Mining in Tuzla, Bosnia and Herzegovina by SBAS-DInSAR Method

The ground subsidence induced by salt mining has been causing significant damage in Tuzla, Bosnia and Herzegovina since the 1950s. Several investigations and geodetic surveys have been conducted, i.e., traditional topographic surveys (1950–2003) and static GPS surveys (2004–2007). The last GPS survey (2006–2007) revealed that the subsidence in Tuzla was still occurring at a rate of about − 10 cm/year in some areas. Although monitoring of the subsidence has been on-going at a few points since 2010, by means of the real-time kinematic GNSS method, it lacks spatial coverage. Therefore, an appropriate method is required to monitor the subsidence over an extensive area at a low cost and with less labor time. Differential Interferometry Synthetic Aperture Radar (DInSAR), together with the Small Baseline Subset (SBAS) time-series algorithm, is one of the solutions for use as an effective monitoring tool. The spatial distribution of the subsidence obtained by SBAS-DInSAR shows a good agreement with the subsidence obtained from the former monitoring results. The temporal transition of the subsidence obtained by SBAS-DInSAR is evaluated using the results by the real-time kinematic GNSS monitoring system. It was shown that the DInSAR results coincide with the GNSS results with a discrepancy of less than 10 mm. SBAS-DInSAR detected that the subsidence had almost vanished everywhere, except the north and northeast portions of Pannonica Lake where the rate of subsidence was − 1 to − 4 cm/year during the period of October 2014–May 2019. This study demonstrates that SBAS-DInSAR can be employed as a useful and effective subsidence monitoring tool without the need to install any devices in the monitoring area.

The kinematic and dynamic characteristics and system optimization design of optical cable based on backtracking method

Optical cable in modern communications is an important facility, and the laying of the optical cable is the key link in the installation. On the basis of analyzing the technological process and ensuring the requirements of optical cable laying, the kinematic parameters the tractor was first optimized and determined by the simplex method. analyzing the motion state and stress state of optical cable laying. E exponential function was selected as the movement mode of the cable to start and stop the cable. The kinematic characteristics of optical cable were programmed with the simplex method, and the optimal acceleration, uniform speed and deceleration distance were obtained corresponding to the three stages. Then the ideal parameters of cable cable’s velocity and acceleration were determined. According to this, the angular acceleration as well as other kinematic and dynamic characteristics of the roller slip roller was obtained ensuring these parameters being in coalescence with those of the tractor. The application study has shown that the system works well and meets the design expectation.

Analytical Analysis of Extreme Position Mechanisms for Conveyor Lifting Segments Using Kinematic Systems

Analytical Analysis of Extreme Position Mechanisms for Conveyor Lifting Segments Using Kinematic Systems

Single-Frequency GPS/BDS RTK and INS Ambiguity Resolution and Positioning Performance Enhanced with Positional Polynomial Fitting Constraint

Single-frequency GPS/BeiDou navigation satellite system (BDS) real-time kinematic (RTK) and inertial navigation system (INS) integration has wide range of application prospects due to the global deployment of GPS along with the rapid development of BDS. The instantaneous single-frequency ambiguity resolution will be significantly improved by the combined GPS/BDS and INS configuration. Owing to road conditions and an inertial measurement unit (IMU) on the carrier not being rigidly mounted, biased measurements in the IMU will occasionally emerge, leading to biased INS predictions. However, bias or inaccuracy from INS-predicted position can prevent the successful resolution of the whole set of ambiguities. This paper proposes the use of a positional polynomial fitting (PPF) constraint to compensate for the epochs with abnormal INS predictions. The aid from PPF is provided at two levels, i.e., at the ambiguity resolution (AR) level and at the solution level. In order to further increase the availability of ambiguity-fixed positioning solutions, a partial ambiguity resolution (PAR) strategy is introduced when full ambiguity resolution (FAR) fails. A field vehicular experiment was performed to show the validity of the proposed PPF-aided method by comparing different schemes regarding different INS-aided satellite system configurations, different AR strategies, and whether the PPF-aided method was adopted. The results show that the most attractive scheme is to combine the PAR with the PPF-aided dual-constellation and INS integration.

Dynamics modeling and attitude stabilization control of a multiarmed space robot for on-orbit servicing

With the number of large-scale facilities, malfunctioning spacecraft, and debris expected to increase in space, on-orbit servicing, including assembly, monitoring, maintenance, refueling and deorbiting, has become a major concern in space missions. Space robots can efficiently cope with a large number of on-orbit servicing missions while avoiding the high risks and reducing costs of extravehicular activity. The challenges of space robots with multiple arms include the complex dynamics and the coupling between the floating base and the end-effector. To handle these problems, a dynamics model with topological structure is firstly established for a four-arm space robot based on the kinematic chain symbolic calculus system and Axis-Invariants, which have the benefits of iterative structure and can avoid complex derivation of traditional dynamics modeling methods. Then, an attitude stabilization strategy consisting of improved nonlinear model predictive control and a hybrid actuator is implemented to handle the disturbance generated by the manipulation of multiple robot arms. The hybrid actuator can provide accurate control torque while simultaneously avoiding the singularity and saturation of the control moment gyro and reaction wheel, respectively. Finally, a scenario of space debris recycling is used to demonstrate the effectiveness of the proposed modeling and control strategy for on-orbit servicing missions with multiarmed space robots.

An Automated Kinematic Measurement System for Sagittal Plane Murine Head Impacts.

Mild traumatic brain injuries are typically caused by nonpenetrating head impacts that accelerate the skull and result in deformation of the brain within the skull. The shear and compressive strains caused by these deformations damage neural and vascular structures and impair their function. Accurate head acceleration measurements are necessary to define the nature of the insult to the brain. A novel murine head tracking system was developed to improve the accuracy and efficiency of kinematic measurements obtained with high-speed videography. A three-dimensional (3D)-printed marker carrier was designed for rigid fixation to the upper jaw and incisors with an elastic strap around the snout. The system was evaluated by impacting cadaveric mice with the closed head impact model of engineered rotational acceleration (CHIMERA) system using an energy of 0.7 J (5.29 m/s). We compared the performance of the head-marker system to the previously used skin-tracking method and documented significant improvements in measurement repeatability (aggregate coefficient of variation (CV) within raters from 15.8 to 1.5 and between raters from 15.5 to 1.5), agreement (aggregate percentage error from 24.9 to 8.7), and temporal response (aggregate temporal curve agreement from 0.668 to 0.941). Additionally, the new system allows for automated software tracking, which dramatically decreases the analysis time required (74% reduction). This novel head tracking system for mice offers an efficient, reliable, and real-time method to measure head kinematics during high-speed impacts using CHIMERA or other rodent or small mammal head impact models.

Characterization of stilbene’s scintillation anisotropy for recoil protons between 0.56 and 10 MeV

The scintillation anisotropy of the single-crystal organic scintillator trans-stilbene was characterized for recoil protons between 0.56 and 10 MeV. The light output and pulse shape anisotropies were measured at 11 distinct recoil proton energies for over 168 recoil proton trajectories relative to the crystal axes. The measurements were performed using a neutron scatter kinematic measurement system and quasi-monoenergetic neutron beams produced by the tandem Van de Graaff accelerator at Triangle Universities Nuclear Laboratory (TUNL). The extensive recoil proton directional coverage enables interpolation over both energy and direction to form a complete response function of stilbene’s scintillation anisotropy for the measured energy range.

Monocular vision-based gripping of objects

Optics-based systems may provide high spatial and temporal resolution for close range object detection in underwater environments. By using a monocular camera on a low cost underwater vehicle manipulator system, objects can be tracked by the vehicle and handled by the manipulator. In this paper, a monocular camera is used to detect an object of interest through object detection. Spatial features of the object are extracted, and a dynamic positioning system is designed for the underwater vehicle in order for it to maintain a desired position relative to the object. A manipulator mounted under the vehicle is used to retrieve the object through a developed kinematic control system. Experimental tests verify the proposed methodology. A stability analysis proves asymptotic stability properties for the chosen sliding mode controller and exponential stability for the task error.

Development of an fMRI-compatible driving simulator with simultaneous measurement of physiological and kinematic signals: The multi-biosignal measurement system for driving (MMSD)

BACKGROUND: A system that comprehensively analyzes a complex perceptual-motor behavior such as driving, by measuring changes in the central and autonomic nervous systems integrated with measurement of changes in vehicle operation, is lacking.OBJECTIVE: We aimed to develop a functional magnetic resonance imaging (fMRI)-compatible driving simulator to enable simultaneous measurement of physiological, kinematic, and brain activations.METHODS: The system mainly comprises a driving simulator and physiological/kinematic measurement. The driving simulator comprises a steering wheel, an accelerator, a brake pedal, and a virtual-reality optical system. The physiological system comprises a skin-conductance-level and a photoplethysmographic meter. The kinematic system comprises a 3-axis accelerometer and a 2-axis gyroscope attached to the accelerator foot. To evaluate the influence of the MR system on the MMSD, physiological and kinematic signals were measured.RESULTS: The system did not blur or deform the MR image. Moreover, the main magnetic field, the gradient magnetic field, and the RF pulse of the MR system did not introduce noise into the physiological or kinematic signals.CONCLUSION: This system can enable a comprehensive evaluation of cognitively complex behaviors such as driving, by quantitatively measuring and analyzing concurrent brain activity, autonomic nervous system activity, and human movement during simulated driving.

THE INFLUENCE OF HUMAN MOVEMENT ON THE FORMATION OF ADAPTIVE ARCHITECTURE

Adaptive architecture relates to buildings that are specially designed to adapt to their inhabitants and their environments and in order to design a biologically adaptive system, we can observe how living creatures in nature are constantly adapting to various external and internal stimuli can be a great source of inspiration. The issue is not just how to create a system capable of change but also how to look for quality change and determine the incentive to adapt. The research deals with the possibilities of transforming spaces by using the human body as an active tool, and the research aims to design and build an effective dynamic structural system that can be applied on an architectural scale and integrate them all into creating a new adaptive system that allows us to envision a new way to design, build and experiment with architecture in a dynamic way. The main objective was to address the possibility of a mutual transition between the user and the architectural component so that the architecture can adapt to the user, as the user adapts to the architecture. Motivation is the desire to engage with the psychological benefits of an environment that can respond and thus empathize with human emotions through its ability to adapt to the user. The adaptive affiliations of kinematic structures have been discussed in architectural research for more than a decade, and these issues have proven their effectiveness in the development of kinematic, responsive and adaptive structures and their contribution to an “intelligent architecture”. A wide range of strategies have also been used in building the mechanisms of complex kinematic and robotic systems to achieve convertibility and adaptability in engineering and architecture. One of the major contributions to this research is the exploration of how the physical environment can alter its shape to accommodate various spatial displays based on the user's body movement. The main focus is on the relationship among materials, shape and reactive control systems and the intent is to create a scenario where the user can move and the structure interacts without any physical contact. , the language of soft form transformation and interaction control technology will provide new possibilities for enriching human-environment interactions.

Magnetic Tests of SNA - HP-59A Kinematic Connection Details in the RD-33 Engine

Abstract Aspects of assessing the technical condition of selected elements of the kinematic system in the renovation of RD-33 engines have been presented. In the beginning, typical operational problems have been discussed, and the test object was defined. Then, the theoretical foundations of three non-destructive testing methods based on magnetic field measurement were discussed. Next, the preliminary results of the research of a defective gear obtained by the magnetic metal memory method are presented. Finally, the conclusions have been made.

Simulation of the landform change process on a purple soil slope due to tillage erosion and water erosion using UAV technology

Both tillage erosion and water erosion are severe erosional forms that occur widely on sloping agricultural land. However, previous studies have rarely considered the process of landform change due to continuous simulation experiments of alternating tillage erosion and water erosion. To identify such changes, we applied a scouring experiment (at a 60 L min−1 water discharge rate based on precipitation data from the local meteorological station and the catchment area in the Yuanmou County, Yunnan Province, China) and a series of simulated tillage experiments where plots were consecutively tilled 5, 10, and 15 times in rotation (representing 5 yr, 10 yr, and 15 yr of tillage) at slope gradients of 5°, 10°, and 20°. Close-range photogrammetry (CRP) employing an unmanned aerial vehicle (UAV) and a real-time kinematic global positioning system (RTK-GPS) was used to measure landform changes, and high-resolution digital elevation models (DEMs) were generated to calculate net soil loss volumes. Additionally, the CRP was determined to be accurate and applicable through the use of erosion pins. The average tillage erosion rates were 69.85, 131.45, and 155.34 t·hm−2·tillage pass−1, and the average water erosion rates were 1892.52, 2961.76, and 4405.93 t·hm−2·h−1 for the 5°, 10°, and 20° sloping farmland plots, respectively. The water erosion rates increased as tillage intensity increased, indicating that tillage erosion accelerates water erosion. Following these intensive tillage treatments, slope gradients gradually decreased, while the trend in slope gradients increased in runoff plots at the conclusion of the scouring experiment. Compared to the original plots (prior to our experiments), interactions between tillage and water erosion caused no obvious change in the landform structure of the runoff plots, while the height of all the runoff plots decreased. Our findings showed that both tillage erosion and water erosion caused a pseudo-steady-state landform evolutionary mechanism and resulted in thin soil layers on cultivated land composed of purple soil in China.

Comparative analysis of real-time kinematic and PPP techniques in dynamic environment

The main objective of this study is to assess the performance of the relative Real-time Kinematic (RTK) Global Navigation Satellite System (GNSS) Methods; i.e., Single-baseline & Network RTK, and Real-time Precise Point Positioning (RT-PPP); i.e., Trimble CenterPoint Real Time eXtended (RTX) Correction Service in a dynamic environment. For this purpose, a kinematic test was done within a vessel in Obruk Lake Dam in Çorum province, Turkey. The test area was situated in a deep valley and surrounded by high hills covered with dense trees. The real-time coordinates of each measurement epoch were simultaneously determined with Single-baseline RTK, Network RTK, and RTX RT-PPP methods by using three GNSS receivers. The real-time coordinates obtained from both RTK and RT-PPP methods were compared against the post-processed relative solution epoch-by-epoch. The results show that, the 3D position accuracies of real-time methods were found as ±6 cm, ±3 cm and ±7 cm for Single-baseline RTK, Network RTK and RT-PPP methods, respectively. This study demonstrates that although the Network RTK methods provided the best solution among the others, the positioning did not conduct most of the time due to the loss of cellular connection. This was also partially valid for the Single-baseline RTK method because the corrections from the base station via radio-link couldn’t be received due to the rough terrain conditions. However, it was possible to make positioning with RTX Real-time PPP technique using satellite delivery GNSS products (corrections) continuously and in a robust manner within the cm-level accuracy. Our study showed that the use of the global multi-GNSS RTX correction service outcompetes conventional RTK methods with providing consistent, reliable, and seamless cm-level accurate positioning almost without any interruption especially in challenging marine environments with severe terrain obstructions.

Feasibility study on piston-based feedstock fabrication with Ti-6Al-4V metal injection molding feedstock

The use of feedstocks from metal injection molding (MIM) for the additive manufacturing (AM) of green parts, which are then debound and sintered in a process called shaping, debinding, and sintering (SDS), is promising in terms of production costs of metallic parts. However, in order to use the cost-efficient AM technique fused filament fabrication (FFF) for SDS, powder-binder mixtures known for MIM feedstocks must be adapted to filament requirements resulting in adjustments to debinding and sintering. In contrast to FFF, screw-based material extrusion is capable of processing already available MIM feedstocks, but machine costs are high due to complex print heads. In this work, a new process called piston-based feedstock fabrication (PFF) is developed for processing already available MIM feedstocks at comparable costs to FFF. First, the state of the art is reviewed highlighting the potential of piston-based material extrusion for its usage in SDS. Based on the review, an extruder module is developed which is integrated into a kinematic system. Experimental studies are performed to validate the developed PFF printer. As material, a Ti-6Al-4V MIM feedstock is used. Thresholds for piston speed (0.175 mm/min), extrusion temperature (80 °C), and nozzle diameter (0.4 mm) are determined to ensure a viscosity that allows to control the extrusion process via steps per mm. With these thresholds it is found that a constant extrusion process can be established in a filling range of the cylinder up to 155 mm. Finally, the performance of the PFF system is evaluated in terms of nozzle geometry, print speed, and reproducibility showing that reproducible green part properties are achieved at a maximum speed of 8.18 mm/s while using a tapered FFF nozzle.

Late Quaternary fluvial landform evolution and controlling factors along the Yulin River on the Northern Tibetan Plateau

The Yulin River in the northern Tibetan Plateau, consists of multiple geomorphological features, including alluvial fans, fluvial terraces, and river profile knickpoints. Collectively, these provide a natural laboratory for exploring the late Quaternary fluvial landform evolution in response to both climatic change and tectonic activities in the region of the Altyn Tagh Fault. In this study, we investigated the distribution, sequences and sediment characteristics of the fluvial landforms along the Yulin River based on high-precision (0.5 m-resolution) Worldview satellite images and field observations. Mid-Pleistocene alluvial fans formed the highest fluvial landform surface into which ten major inset fluvial terraces were developed, distributed along three stream segments. Real-time kinematic global positioning system (RTK-GPS) measurement of terrace surfaces and the modern river longitudinal profiles was conducted across the Dongbatu Shan to show fluvial landform geometry and tectonic deformation. Fluvial terrace surfaces were deformed due to fault uplift as illustrated by spatially variable surface geometries. The chronological sequences of terraces along the Yulin River since 160 ka were reconstructed based on 10Be terrestrial cosmogenic nuclides (TCNs) dating. Results indicated that river incision occurred mainly during periods of climate transition, suggesting that terrace evolution was partly controlled by climate changes. Moreover, terrace exposure ages showed an upstream younging trend along the river, demonstrating a probable response to knickpoint retreat. Combined with terrace deformation and ages, fault uplift rates were constrained, which were lower than the river incision rates during the Late Quaternary, indicating that crustal shortening was mainly absorbed by the growth of the regional anticline. Collectively, our results suggest that the evolution of fluvial landforms along the Yulin River is a function of interplay between regional tectonic activities and climatic changes, which is significant to understand the NW-outward splay of the Altyn Tagh Fault.

Intelligent rolling compaction system for earth-rock dams

The compaction quality of earth-rock dams primarily depends on manual control of the compaction parameters during construction and random spot tests after construction. However, manual control of the compaction parameters can result in more control errors and quality defects and cannot satisfy the requirements of construction operations under all weather and extreme conditions. Additionally, spot tests with characteristics such as random and destructive detection, low efficiency, and high costs cannot adequately reflect the compaction status of an entire area or satisfy the requirements of rapid mechanised construction. This paper presents an intelligent rolling compaction method based on a new framework of material-machine-information-machine intelligent decision-making for earth-rock dams. Using the proposed system integration method based on three-layer structure, IRC system can be obtained by integrating the continuous compaction control acoustic wave detection (CAWD) system combined with real-time kinematic global positioning system (RTK-GPS), intelligent decision-making (IDM) system based on the global compaction process-dynamic optimisation method (GCPDOM), unmanned rolling compaction (URC) system based on automatic driving technology, and real-time remote monitoring centre based on the triangle architecture. The implementation of the proposed system in the Qianping Reservoir construction site has shown that its operation is stable and reliable, and it can effectively eliminate the impact of human factors on compaction quality control, thereby significantly improving the compaction quality and construction efficiency of earth-rock dams.

Occupant-centered optimization framework to evaluate and design new dynamic shading typologies.

Dynamic solar shading has the potential to dramatically reduce the energy consumption in buildings while at the same time improving the thermal and visual comfort of its occupants. Many new typologies of shading systems that have appeared recently, but it is difficult to compare those new systems to existing typologies due to control algorithm being rule-based as opposed to performance driven. Since solar shading is a design problem, there is no single right answer. What is the metric to determine if a system has reached its optimal kinematic design? Shading solutions should come from a thorough iterative and comparative process. This paper provides an original and flexible framework for the design and performance optimization of dynamic shading systems based on interpolation of simulations and global minimization. The methodology departs from existing rule-based strategies and applies to existing and to complex shading systems with multiple degree-of-freedom mobility. The strategy for control is centered on meeting comfort targets for work plane illuminance while minimizing the energy needed to operate space. The energy demand for thermal comfort and work plane daylight quantity (illuminance) are evaluated with Radiance and EnergyPlus based on local weather data. Applied to a case study of three typologies of dynamic shading, the results of the methodology inform the usefulness and quality of each degree-of-freedom of the kinematic systems. The case study exemplifies the iterative benefits of the methodology by providing detailed analytics on the behavior of the shades. Designers of shading systems can use this framework to evaluate their design and compare them to existing shading systems. This allows creativity to be guided so that eventually building occupants benefit from the innovation in the field.

UWB WITH AGV FOR LOCALIZATION SYSTEM

Automated guided vehicle (AGV) has great significance in material flow and distribution of goods with high precision and efficiency. Besides, Ultra-wideband (UWB) is a technology used to transmit wireless signal in nanosecond. In this paper, localization system using AGV via UWB is designed. Futhermore, the experiment of localization with AGV is introduced and the result is disscused. In addition, control system for AGV is developed by using kinematic control system via Labview.

Robust Output Path-Following Control of Marine Surface Vessels with Finite-Time LOS Guidance

This paper proposes a finite-time output feedback methodology for the path-following task of marine surface vessels. First, a horizontal path-following model is established with unknown sideslip angle, unmeasured system state and system uncertainties. A hierarchical control structure is adopted to deal with the cascade property. For kinematics system design, a finite-time sideslip angle observer is first proposed, and thus the sideslip angle estimation is compensated in a nonlinear line-of-sight (LOS) guidance strategy to acquire finite-time convergence. For the heading control design, an extended state observer is introduced for the unmeasured state and equivalent disturbance estimation, based on which an output feedback backstepping approach is proposed for the desired tracking of command course angle. The global stability of the cascade system is analyzed. Simulation results validate the effectiveness of the proposed methodology.

Engineering a Compliant Mechanical Amplifier for MEMS Sensor Applications

In this paper, we introduce a compliant mechanical amplifier (mechAMP) suitable for the sensitivity enhancement in MEMS sensor applications. The design, fabrication and characterization of a planar compliant amplifier mechanism is presented with special focus on the kinematic and static system modelling of the displacement and force amplification. We show that the proposed system can also be applied as mechanical stiffness transformer for the adaption of mechanical signals or as mechanical transformer for MEMS actuators. Based on a kinematic model, a compact mechanism with a system size of 930 $\mu \text{m}\,\,\times2080\,\,\mu \text{m}$ and a displacement amplification ratio of 200 with an output displacement in a range of 100 $\mu \text{m}$ was designed. The fabrication of the system was carried out using silicon-on-insulator (SOI) technology. Experimentally, we could verify an amplification ratio of 197.9 for the designed and fabricated system which corresponds to the analytic model by a deviation of about 1%. [2019-0228]