Scan Design Research Articles

TLSynth: A Novel Blender Add-On for Real-Time Point Cloud Generation from 3D Models

Point clouds are a crucial element in the process of scanning and reconstructing 3D environments, such as buildings or heritage sites. They allow for the creation of 3D models that can be used in a wide range of applications. In some cases, however, only the 3D model of an environment is available, and it is necessary to obtain point clouds with the same characteristics as those captured by a laser scanner. For instance, point clouds may be required for surveys, performance optimization, site scan planning, or validation of point cloud processing algorithms. This paper presents a new terrestrial laser scanner (TLS) simulator, designed as a Blender add-on, that produces synthetic point clouds from 3D models in real time. The simulator allows users to adjust a set of parameters to replicate real-world scanning conditions, such as noise generation, ensuring the synthetic point clouds closely mirror those produced by actual laser scanners. The target meshes may be derived from either a real-world scan or 3D designs created using design software. By replicating the spatial distributions and attributes of real laser scanner outputs and supporting real-time generation, the simulator serves as a valuable tool for scan planning and the development of synthetic point cloud repositories, advancing research and practical applications in 3D computer vision.

A Precessing-Coin-like Rotary Actuator for Distal Endoscope Scanners: Proof-of-Concept Study.

This paper presents, for the first time, a rotary actuator functionalized by an inclined disc rotor that serves as a distal optical scanner for endoscopic probes, enabling side-viewing endoscopy in luminal organs using different imaging/analytic modalities such as optical coherence tomography and Raman spectroscopy. This scanner uses a magnetic rotor designed to have a mirror surface on its backside, being electromagnetically driven to roll around the cone-shaped hollow base to create a motion just like a precessing coin. An optical probing beam directed from the probe's optic fiber is passed through the hollow cone to be incident and bent on the back mirror of the rotating inclined rotor, circulating the probing beam around the scanner for full 360° sideway imaging. This new scanner architecture removes the need for a separate prism mirror and holding mechanics to drastically simplify the scanner design and thus, potentially enhancing device miniaturization and reliability. The first proof-of-concept is developed using 3D printing and experimentally analyzed to reveal the ability of both angular stepping at 45° and high-speed rotation up to 1500 rpm within the biologically safe temperature range, a key function for multimodal imaging. Preliminary optical testing demonstrates continuous circumferential scanning of the laser beam with no blind spot caused by power leads to the actuator. The results indicate the fundamental feasibility of the developed actuator as an endoscopic distal scanner, a significant step to further development toward advancing optical endoscope technology.

Robotics and optical coherence tomography: current works and future perspectives [Invited

Optical coherence tomography (OCT) is an interferometric technique for micron-level imaging in biological and non-biological contexts. As a non-invasive, non-ionizing, and video-rate imaging modality, OCT is widely used in biomedical and clinical applications, especially ophthalmology, where it functions in many roles, including tissue mapping, disease diagnosis, and intrasurgical visualization. In recent years, the rapid growth of medical robotics has led to new applications for OCT, primarily for 3D free-space scanning, volumetric perception, and novel optical designs for specialized medical applications. This review paper surveys these recent developments at the intersection of OCT and robotics and organizes them by degree of integration and application, with a focus on biomedical and clinical topics. We conclude with perspectives on how these recent innovations may lead to further advances in imaging and medical technology.

Application of the full digital workflow in immediate removable partial denture: an innovative case report

Background. The fabrication of immediate removable partial dentures (RPDs) is characterized by the integration of digital technologies that enhance precision and efficiency in prosthodontic care. The application of a full digital workflow in this context is increasingly recognized for its potential to address both functional and esthetic needs of patients. The estimated prevalence of immediate RPDs in clinical practice is rising, yet literature exploring their digital fabrication remains limited. To our knowledge, this case report presents one of the first instances of utilizing a comprehensive digital approach for the creation of immediate RPDs, highlighting its benefits in patient outcomes. Case report. A 62-year-old male patient with maxillary anterior incisors mobility opted for immediate RPD treatment due to functional pain and esthetic concerns. Intraoral scanning was employed for impression taking and occlusion registration, generating Standard Tessellation Language files. Cone beam computed tomography provided Digital Imaging and Communication in Medicine (DICOM) files, enabling precise virtual extraction of the incisors and ridge smoothening using Exocad software. The denture design, teeth mounting, and surgical guide were digitally planned based on digital smile design outcomes. Digital light processing was utilized for prosthesis manufacturing, and assembly followed a detailed protocol outlined in the present paper. Post-extraction, regular follow-up sessions are essential to assess patient satisfaction. Conclusions. The integration of intraoral scanning and Computer-Aided Design and Manufacturing CAD/CAM technology offered a promising solution for the rapid production of immediate RPDs with enhanced accuracy and reproducibility. The successful assembly and long-term durability of 3D printed dentures were achieved through strategic design considerations and meticulous data processing.

Establishing a CAD/CAM workflow for stabilization appliances (Michigan splints).

Stabilization appliances (Michigan splints) are well studied and widely adopted for managing bruxism and temporomandibular disorders (TMDs). Traditionally, these appliances have been fabricated by wax modeling and pressing resin onto casts made from irreversible hydrocolloid or silicone impressions. This article provides a detailed description of an all-digital workflow that uses intraoral scanning and computer-aided design (CAD) software to design a stabilization splint on a digital cast that can be manufactured autonomously by a computer-aided manufacturing (CAM) grinding machine in a subtractive procedure. The workflow is applicable to both dental practitioners and technicians. Special attention is given to aspects and procedures that are important for the successful fabrication of the splint. Working without a cast can save time and money, and the use of CAD/CAM technology provides a homogenous splint material quality.

Reducing the Energy Consumption of Magnetic Resonance Imaging and Computed Tomography Scanners: Integrating Ecodesign and Sustainable Operations.

This review aims to provide valuable insights into how energy consumption in magnetic resonance imaging (MRI) and computed tomography (CT) scanners can be effectively monitored, managed, and reduced, thereby contributing to more sustainable medical imaging practices. Demand for advanced imaging technologies such as MRI and CT scanners continues to increase, and understanding the resultant impact on greenhouse gas emissions requires a thorough evaluation of their energy consumption. This review examines the energy monitoring and consumption characteristics of MRI and CT scanners, highlighting potential approaches for energy savings. An overview of MRI and CT principles, hardware components, and their associated energy consumption is provided. After addressing the technical aspects, the hardware and software requirements essential for accurate energy metering are detailed. Baseline measurements of energy consumption data are then provided as a foundation to understand current usage patterns and identify areas for improvement. Ongoing efforts to reduce energy consumption are categorized into 3 main strategies: operations, scanner design enhancements, and active scanning techniques, including accelerated MRI protocols. Ultimately, we emphasize that achieving sustainability in medical imaging requires collaboration across disciplines. By incorporating eco-friendly design in new imaging equipment, we can reduce the environmental impact, promote sustainability, and set a health care industry standard for a healthier planet.

Optimizing Switching Activity using LFSR-Driven Logic for VLSI Circuits

In Very-Large-Scale-Integration (VLSI) designs, thorough testing is indispensable for identifying the structural defects of the chip. Timely detection and correcting serious defects are pivotal in preventing faulty chips from reaching customers and avoiding failures. In scan designs, the toggling activity is a critical factor due to the defects between lower cells and metal layers, exacerbated by diverse Process, Voltage, and Temperature (PVT) conditions. These defects significantly impact design testability, quality, and reliability, necessitating meticulous testing to ensure that chips meet the desired specifications. Effectively managing power consumption in the current VLSI landscape is crucial amid the ongoing energy crisis. Balancing the need for Low-Power (LP) with the complexity of integrating transistors onto a single silicon substrate poses significant challenges. As chip densities increase, power dissipation during testing surges, adversely affecting durability, performance, cost, and reliability. Engineers are racing to optimize test power usage, employing advanced Design for Test (DFT) techniques to incorporate efficient power management into Silicon-on-Chip (SoC) designs. Linear Feedback Shift Registers (LFSRs) are phenomenal in addressing DFT parameters like power, and performance, and for better pseudo-random pattern generation. Hence, this paper proposes a groundbreaking approach to power reduction techniques deploying the LFSR architecture, and thus challenging conventional scan-based testing methods. The proposed LFSR architecture is meticulously designed and rigorously tested using Cadence DFT Modus solution on ISCAS’89 benchmarking circuits. Coverage was unequivocally evaluated for Quality of Results (QoR) metrics, such as fault coverage, memory usage, pattern counts, switching activity, fault testing, and runtime. The specific evaluation clearly proved the superiority of the LFSR-based approach over the scan-based architecture. Adopting the novel LFSR architecture resulted in a ~5.6X reduction in toggling activity accompanied by a substantial ~10K pattern reduction and a runtime of nearly ~1.5 hours. Notably, the test power was reduced to 50% showcasing superior efficiency. This approach emerges as the ideal solution for industrial designs providing the best QoR for power, performance, and area. This innovative methodology marks a significant leap toward an energy-efficient and cost-effective VLSI circuit especially for stacked 2.5-3D ICs and chiplets poised to revolutionize chip manufacturing.

Design of a self-referenced laser scanning and ranging system

Design of a self-referenced laser scanning and ranging system

Linear and Volumetric Polyethylene Wear Patterns after Primary Cruciate-Retaining Total Knee Arthroplasty Failure: An Analysis Using Optical Scanning and Computer-Aided Design Models.

(1) Background: Analyses of retrieved inserts allow for a better understanding of TKA failure mechanisms and the detection of factors that cause increased wear. The purpose of this implant retrieval study was to identify whether insert volumetric wear significantly differs among groups of common causes of total knee arthroplasty failure, whether there is a characteristic wear distribution pattern for a common cause of failure, and whether nominal insert size and component size ratio (femur-to-insert) influence linear and volumetric wear rates. (2) Methods: We digitally reconstructed 59 retrieved single-model cruciate-retaining inserts and computed their articular load-bearing surface wear utilizing an optical scanner and computer-aided design models as references. After comprehensively reviewing all cases, each was categorized into one or more of the following groups: prosthetic joint infection, osteolysis, clinical loosening of the component, joint malalignment or component malposition, instability, and other isolated causes. The associations between volumetric wear and causes of failure were estimated using a multiple linear regression model adjusted for time in situ. Insert linear penetration wear maps from the respective groups of failure were further processed and merged to create a single average binary image, highlighting a potential wear distribution pattern. The differences in wear rates according to nominal insert size (small vs. medium vs. large) and component size ratio (≤1 vs. >1) were tested using the Kruskal-Wallis test and the Mann-Whitney test, respectively. (3) Results: Patients with identified osteolysis alone and those also with clinical loosening of the component had significantly higher volumetric wear when compared to those without both causes (p = 0.016 and p = 0.009, respectively). All other causes were not significantly associated with volumetric wear. The instability group differentiated from the others with a combined peripheral antero-posterior wear distribution. Linear and volumetric wear rates showed no significant differences when compared by nominal insert size (small vs. medium vs. large, p = 0.563 and p = 0.747, respectively) or by component (femoral-to-insert) size ratio (≤1 vs. >1, p = 0.885 and p = 0.055, respectively). (4) Conclusions: The study found increased volumetric wear in cases of osteolysis alone, with greater wear when combined with clinical loosening compared to other groups. The instability group demonstrated a characteristic peripheral anterior and posterior wear pattern. Insert size and component size ratio seem not to influence wear rates.

A Modified and Customized Wingsuit Flying Search (MCWFS)-based Approach for the Circular Scan Architecture

The circular scan architecture (CSA) is a widely used scan design technique in digital circuit testing that involves scanning test data through a circuit in a circular pattern. Several optimization approaches have been suggested so far to lessen the Test Data Volume (TDV), but no one has shown satisfactory results. Therefore, this paper proposes a Modified and Customized Wingsuit Flying Search algorithm to decrease the test data volume time. The proposed MCWFS-SBA-CSA introduces some novel features that distinguish it from traditional circular scan approaches. The concept of wingsuit flying is an innovative approach in the field of scan systems. This allows the scan that moves more dynamically and efficiently, enabling it to cover a larger area in a shorter time than traditional circular-scan approaches. After this phase, only scan-chosen inputs are required to obtain the next test pattern from the captured response. Therefore, required less Automatic test equipment (ATE) memory in this research so there is a Decreased cost in system-on-chip (SOC). The proposed method attains fast global searching capacity. The efficiency of the proposed technique attains 26.42%, 32.45%, and 29.34% higher compression ratio (CR), Test Application Time (TAT) reduction of SC-128 attains 29.45%, 34.67%, and 40.22% higher, TDV of SC-256 attains 32.23%, 36.34%, and 39.23% higher than existing methods, such as TDV for Circular Scan Approaches utilizing Modified Shuffled Shepard Optimization (TDV-CSA-MSSO), Effectual Very-large-scale integration Test data compression system for CSA under modified and colony metaheuristic (ETDC-CSA-MACMH), and Test Data Compression Utilizing Tetrad state Skip System (TDC-DC-TSSC) for Digital Circuits, respectively.

Design Optimisation of a Flat-Panel, Limited-Angle TOF-PET Scanner: A Simulation Study.

In time-of-flight positron emission tomography (TOF-PET), a coincidence time resolution (CTR) below 100 ps reduces the angular coverage requirements and, thus, the geometric constraints of the scanner design. Among other possibilities, this opens the possibility of using flat-panel PET detectors. Such a design would be more cost-accessible and compact and allow for a higher degree of modularity than a conventional ring scanner. However, achieving adequate CTR is a considerable challenge and requires improvements at every level of detection. Based on recent results in the ongoing development of optimised TOF-PET photodetectors and electronics, we expect that within a few years, a CTR of about 75 ps will be be achievable at the system level. In this work, flat-panel scanners with four panels and various design parameters were simulated, assessed and compared to a reference scanner based on the Siemens Biograph Vision using NEMA NU 2-2018 metrics. Point sources were also simulated, and a method for evaluating spatial resolution that is more appropriate for flat-panel geometry is presented. We also studied the effects of crystal readout strategies, comparing single-crystal and module readout levels. The results demonstrate that with a CTR below 100 ps, a flat-panel scanner can achieve image quality comparable to that of a reference clinical scanner, with considerable savings in scintillator material.

Penggunaan Prototype Media Pembelajaran Untuk Anak Usia Dini Menggunakan Teknik Scan Tiga Dimensi

This research creates a prototype of learning media for early childhood using 3D scanning techniques. The prototype is designed to introduce the variety of endemic fauna in Indonesia. The research method is Analysis, Design, Development, Implementation, and Evaluation (ADDIE). This learning media is designed with five stages: Analyzing the proximity between children and technology, designing animal icons and maps, designing a 3D scan prototype using Polycam Pro, testing the 3D Scan prototype, implementation of the 3D Scan prototype. Designing a 3D Scan using Polycam Pro is better using manual methods to produce images with clear textures. 3D Scan design using Polycam Pro produces 3D shapes of endemic animal objects that are published on the web as learning media for early childhood.

Considerations for practical use of tree-based scan statistics for signal detection using electronic healthcare data: a case study with insulin glargine

ABSTRACT Background Hypothesis-free signal detection (HFSD) methods such as tree-based scan statistics (TBSS) applied to longitudinal electronic healthcare data (EHD) are increasingly used in safety monitoring. However, challenges may arise in interpreting HFSD results alongside results from disproportionality analysis of spontaneous reporting. Research design and methods Using the anti-diabetes drug insulin glargine (Lantus®) we apply two different tree-based scan designs using TreeScan™ software on retrospective EHD and compare the results to one another as well as to results from a disproportionality analysis using SRD. Results The self-controlled tree temporal scan method produced the larger number of alerts relative to propensity-score matched approach; however, far fewer alerts were observed when analyses were limited to EHD in inpatient/emergency room settings only. Very few reference adverse events were observed using TBSS methods on EHD relative to disproportionality methods in SRD. Conclusion Differences in detected alerts between TBSS methods and between TBSS and disproportionality analysis of SRD are likely attributable to differences in data, comparator, and study design. Our results suggest that HFDS methods like TBSS applied to EHD may complement more traditional approaches such as disproportionality analysis of SRD to provide a more complete picture of product safety in the post-approval setting.

Design and Analysis of Jigs and Fixtures for Inspection Process

Abstract: In the realm of vehicle manufacturing, ensuring precise panel fitment is paramount for maintaining quality standards and customer satisfaction. This report delves into the significance of panel and fitment checking fixtures in the automotive industry. The study provides a thorough examination of the design, construction, and utilization of these fixtures, emphasizing their critical role in verifying the accuracy and alignment of vehicle panels during assembly. By employing advanced measurement techniques and precision engineering, these fixtures serve as indispensable tools for detecting deviations and inconsistenciesin panel fitment. Furthermore, the report explores the integration of innovative technologies such as 3D scanning and computer-aided design (CAD) in the development of these fixtures, enabling manufacturers to achieve higher levels of accuracy and efficiency in the quality control process. Through case studies and industry insights, the report showcases the practical application and effectiveness of panel and fitment checking fixtures across various stages of vehicle production. Additionally, it highlights the benefits of implementing standardized fixture designs and methodologies to streamline manufacturing processes and minimize production costs.

Effective engineering of a ketoreductase for the biocatalytic synthesis of an ipatasertib precursor

Semi-rational enzyme engineering is a powerful method to develop industrial biocatalysts. Profiting from advances in molecular biology and bioinformatics, semi-rational approaches can effectively accelerate enzyme engineering campaigns. Here, we present the optimization of a ketoreductase from Sporidiobolus salmonicolor for the chemo-enzymatic synthesis of ipatasertib, a potent protein kinase B inhibitor. Harnessing the power of mutational scanning and structure-guided rational design, we created a 10-amino acid substituted variant exhibiting a 64-fold higher apparent kcat and improved robustness under process conditions compared to the wild-type enzyme. In addition, the benefit of algorithm-aided enzyme engineering was studied to derive correlations in protein sequence-function data, and it was found that the applied Gaussian processes allowed us to reduce enzyme library size. The final scalable and high performing biocatalytic process yielded the alcohol intermediate with ≥ 98% conversion and a diastereomeric excess of 99.7% (R,R-trans) from 100 g L−1 ketone after 30 h. Modelling and kinetic studies shed light on the mechanistic factors governing the improved reaction outcome, with mutations T134V, A238K, M242W and Q245S exerting the most beneficial effect on reduction activity towards the target ketone.

Distal planar rotary scanner for endoscopic optical coherence tomography.

Optical coherence tomography (OCT) is becoming a more common endoscopic imaging modality for detecting and treating disease given its high resolution and image quality. To use OCT for 3-dimensional imaging of small lumen, embedding an optical scanner at the distal end of an endoscopic probe for circumferential scanning the probing light is a promising way to implement high-quality imaging unachievable with the conventional method of revolving an entire probe. To this end, the present work proposes a hollow and planar micro rotary actuator for its use as an endoscopic distal scanner. A miniaturized design of this ferrofluid-assisted electromagnetic actuator is prototyped to act as a full 360° optical scanner, which is integrated at the tip of a fiber-optic probe together with a gradient-index lens for use with OCT. The scanner is revealed to achieve a notably improved dynamic performance that shows a maximum speed of 6500rpm, representing 325% of the same reported with the preceding design, while staying below the thermal limit for safe in-vivo use. The scanner is demonstrated to perform real-time OCT using human fingers as live tissue samples for the imaging tests. The acquired images display no shadows from the electrical wires to the scanner, given its hollow architecture that allows the probing light to pass through the actuator body, as well as the quality high enough to differentiate the dermis from the epidermis while resolving individual sweat glands, proving the effectiveness of the prototyped scanner design for endoscopic OCT application.

Design of continuous zoom area array scanning infrared optical system with large area array

Design of continuous zoom area array scanning infrared optical system with large area array

Design of continuous zoom area array scanning infrared optical system with large area array

Design of continuous zoom area array scanning infrared optical system with large area array

Beam Scanning Design and Performance Analysis for Near-Field IRS-Aided Integrated Sensing and Communication Systems

Beam Scanning Design and Performance Analysis for Near-Field IRS-Aided Integrated Sensing and Communication Systems

A Low-Overhead and High-Security Scan Design Based on Scan Obfuscation

A Low-Overhead and High-Security Scan Design Based on Scan Obfuscation