Concerning quantitative calibration, four different GelStereo sensing platforms were rigorously tested; the experimental results reveal that the suggested calibration pipeline achieves Euclidean distance errors under 0.35 mm, highlighting the applicability of this refractive calibration method in diverse GelStereo-type and analogous visuotactile sensing systems. High-precision visuotactile sensors can significantly aid research into the dexterity of robots in manipulation tasks.
A novel omnidirectional observation and imaging system, the arc array synthetic aperture radar (AA-SAR), has emerged. Employing linear array 3D imaging, this paper presents a keystone algorithm integrated with arc array SAR 2D imaging, subsequently proposing a modified 3D imaging algorithm reliant on keystone transformation. Medicina perioperatoria To begin, the target's azimuth angle needs to be discussed, using the far-field approximation method from the primary term. Following this, a careful investigation into how the platform's forward movement affects the location along the track must be conducted. This is to enable a two-dimensional concentration on the target's slant range and azimuth. In the second step, a new azimuth angle variable is introduced within slant-range along-track imaging. Subsequently, the keystone-based processing algorithm within the range frequency domain is applied to eliminate the coupling term arising from the array angle and slant-range time. Employing the corrected data, along-track pulse compression is performed to generate a focused target image, enabling three-dimensional target visualization. Within the concluding part of this article, a detailed investigation into the forward-looking spatial resolution of the AA-SAR system is undertaken, verified by simulations, showing the changes in resolution and evaluating the effectiveness of the algorithm.
Independent living for older adults is often compromised by a range of problems, from memory difficulties to problems with decision-making. In this work, an integrated conceptual model for assisted living systems is introduced, providing support for elderly individuals with mild memory impairments and their caregivers. A four-part model is proposed: (1) an indoor localization and heading measurement system within the local fog layer, (2) an augmented reality application for user interaction, (3) an IoT-based fuzzy decision-making system for handling user and environmental interactions, and (4) a real-time user interface for caregivers to monitor the situation and issue reminders. To evaluate the feasibility of the proposed mode, a preliminary proof-of-concept implementation is executed. The effectiveness of the proposed approach is validated through functional experiments conducted based on a variety of factual scenarios. The proposed proof-of-concept system's accuracy and response time are further investigated. The results indicate the practicality of introducing such a system and its potential for boosting assisted living. By promoting scalable and customizable assisted living systems, the suggested system aims to reduce the obstacles associated with independent living for older adults.
A multi-layered 3D NDT (normal distribution transform) scan-matching strategy, robustly localizing in the highly dynamic warehouse logistics domain, is presented in this paper. By considering the vertical variations in the environment, we divided the input 3D point-cloud map and scan measurements into various layers. For each layer, covariance estimations were computed via 3D NDT scan-matching. Because the covariance determinant quantifies the estimation uncertainty, we can select optimal layers for warehouse localization. When the layer comes close to the warehouse's floor, considerable environmental alterations, like the warehouse's chaotic structure and the positioning of boxes, exist, though it contains numerous good qualities for scan-matching. If a particular layer's observed data cannot be adequately explained, alternative layers demonstrating lower uncertainties are a viable option for localization. Hence, the significant contribution of this approach is the improved resilience of localization, especially in scenes characterized by substantial clutter and rapid movement. Simulation-based validation using Nvidia's Omniverse Isaac sim, along with detailed mathematical descriptions, are provided by this study for the proposed method. The evaluative results of this study can establish a compelling starting point to design better countermeasures against occlusion in warehouse navigation for mobile robots.
Monitoring information enables the evaluation of the condition of railway infrastructure by delivering data that is informative about its state. The dynamic interaction between the vehicle and the track is uniquely captured by Axle Box Accelerations (ABAs), an exemplary dataset element. By installing sensors on specialized monitoring trains and active On-Board Monitoring (OBM) vehicles throughout Europe, continuous evaluation of railway track conditions is now possible. ABA measurements are affected by the uncertainties arising from noise in the data, the intricate non-linear interactions of the rail and wheel, and variations in environmental and operating conditions. Assessing the condition of rail welds using current assessment tools is hampered by these uncertainties. This work leverages expert input alongside other information to reduce ambiguity in the assessment process, ultimately resulting in a more refined evaluation. learn more For the past year, with the Swiss Federal Railways (SBB) providing crucial support, we have developed a database containing expert assessments of the condition of critical rail weld samples, as identified through ABA monitoring. To refine the identification of faulty welds, this study fuses features from ABA data with expert input. These three models are instrumental in this effort: Binary Classification, Random Forest (RF), and Bayesian Logistic Regression (BLR). The Binary Classification model's performance was surpassed by both the RF and BLR models, with the BLR model offering an added dimension of predictive probability to quantify our confidence in the assigned labels. The classification task's high uncertainty, stemming from faulty ground truth labels, necessitates continuous tracking of the weld condition, a practice of demonstrable value.
Maintaining communication quality is of utmost importance in the utilization of unmanned aerial vehicle (UAV) formation technology, given the restricted nature of power and spectrum resources. For the purpose of optimizing both the transmission rate and the likelihood of successful data transfer in a UAV formation communication system, a deep Q-network (DQN) architecture was enhanced with convolutional block attention module (CBAM) and value decomposition network (VDN) algorithms. This paper considers the simultaneous operation of UAV-to-base station (U2B) and UAV-to-UAV (U2U) links, in the context of maximizing frequency utilization, while also examining the possibility of reusing U2B links within U2U communication. patient-centered medical home Within the DQN architecture, the U2U links, functioning as agents, dynamically interact with the system, developing intelligent strategies for power and spectrum selection. The training process is altered by CBAM across both the channel and spatial dimensions, affecting the outcome. The VDN algorithm was introduced to address the partial observation problem in a single UAV, with distributed execution providing the mechanism. This mechanism facilitated the decomposition of the team q-function into separate agent-specific q-functions using the VDN approach. Substantial enhancement in both data transfer rate and the probability of successful data transmission was observed in the experimental results.
Essential to the functionality of the Internet of Vehicles (IoV) is License Plate Recognition (LPR), as license plates provide a necessary means of distinguishing and managing vehicles within traffic flow. A continuous surge in the number of vehicles on the roadways has led to a more complex challenge in the areas of traffic management and control. Large urban centers, in particular, encounter substantial obstacles, encompassing worries about data protection and resource utilization. In response to these challenges, the emergence of automatic license plate recognition (LPR) technology within the Internet of Vehicles (IoV) is a crucial area of academic study. Roadway LPR's function of detecting and identifying license plates significantly improves the control and management of the transportation system. Careful consideration of privacy and trust is crucial when implementing LPR systems within automated transportation, particularly concerning the collection and application of sensitive data. The current investigation supports a blockchain-based method for IoV privacy security that makes use of LPR technology. A user's license plate is registered directly on the blockchain ledger, dispensing with the gateway process. With the addition of more vehicles to the system, the database controller runs the risk of crashing. License plate recognition, in conjunction with blockchain technology, is utilized in this paper to create a privacy preservation system for the IoV. When an LPR system detects a license plate, the associated image is routed to the gateway that handles all communication tasks. A user's license plate registration is handled by a blockchain-based system that operates independently from the gateway, when required. Besides this, in a traditional IoV system, the central authority is empowered with complete oversight of the binding process for vehicle identification and public keys. A surge in the number of vehicles traversing the system could induce a crash in the central server's operations. Analyzing vehicle behavior is the core of the key revocation process, which the blockchain system employs to identify and revoke the public keys of malicious users.
This paper introduces an enhanced robust adaptive cubature Kalman filter (IRACKF) to address the challenges of non-line-of-sight (NLOS) observation errors and inaccurate kinematic models in ultra-wideband (UWB) systems.