CAD Files Research Articles

A numerical investigation of stress, strain, and bone density changes due to bone remodelling in the talus bone following total ankle arthroplasty

Total ankle arthroplasty is the gold standard surgical treatment for severe ankle arthritis and fracture. However, revision surgeries due to the in vivo failure of the ankle implant are a serious concern. Extreme bone density loss due to bone remodelling is one of the main reasons for in situ implant loosening, with aseptic loosening of the talar component being one of the primary reasons for total ankle arthroplasty revisions. This study is aimed at determining the performance and potential causes of failure of the talar component. Herein, we investigated the stress, strain, and bone density changes that take place in the talus bone during the first 6 months of bone remodelling due to the total ankle arthroplasty procedure. Computed tomography scans were used to generate the 3D geometry used in the finite element (FE) model of the Intact and implanted ankle. The Scandinavian Total Ankle Replacement (STAR™) CAD files were generated, and virtual placement within bone models was done following surgical guidelines. The dorsiflexion physiological loading condition was investigated. The cortical region of the talus bone was found to demonstrate the highest values of stress (5.02 MPa). Next, the adaptive bone remodelling theory was used to predict bone density changes over the initial 6-month post-surgery. A significant change in bone density was observed in the talus bone due to bone remodelling. The observed quantitative changes in talus bone density over 6-month period underscore potential implications for implant stability and fracture susceptibility. These findings emphasise the importance of considering such biomechanical factors in ankle implant design and clinical management.

Deep learning-based error recognition in manual cable assembly using synthetic training data

Assembly states can be automatically recognized using deep learning models for computer vision. However, the requisite extensive effort and specialized know-how for training data preparation pose significant hurdles for industrial application. To overcome this issue, methods to generate training data synthetically have been implemented. Yet, they do not close the gap from state- to error-recognition. Timely recognition of not only states but errors is crucial to mitigate high error costs in manual assembly processes.We propose the usage of an adaptable object detection-based error recognition that is evaluated in a real-world industrial scenario, where multiple components must be assembled onto a cable in a specified sequence. The deployed object detection model is purely based on synthetic images rendered from CAD files. In contrast to existing literature, the proposed solution allows to define various error states.In evaluation, a mAP0.5 of 99.2 % for object detection could be reached and the correct and various erroneous assembly states could be recognized with 96.25 % accuracy. These results highlight the potential of this solution for automated error recognition, which can ultimately reduce assembly errors and the resulting failure related costs in industrial applications. Future projects will transfer these learnings to more complex manual assembly scenarios.

Palatal vault configuration and its influence on intraoral scan time and accuracy in completely edentulous arches: a prospective clinical study.

The aim of this prospective clinical study was to compare the influence of palatal vault forms on accuracy and speed of intraoral (IO) scans in completely edentulous cases. Based on the palatal vault form, participants were divided into three equal groups (n = 10 each); Class I: moderate; Class II: deep; Class III: flat palatal vault. A reference model was created for each patient using polyvinylsiloxane impression material. The poured models were digitized using an extraoral scanner. The resultant data were imported as a solid CAD file into 3D analysis software (GOM Inspect 2018; Gom GmbH, Braunschweig, Germany) and aligned using the software's coordinate system to determine its X, Y, and Z axes. Five digital impressions (DIs) of maxilla were captured for each patient using an intraoral scanner (TRIOS; 3Shape A/S, Copenhagen, Denmark) and the resultant Standard Tessellation Language (STL) scan files served as test models. Trueness was evaluated by calculating arithmetic mean deviation (AMD) of the vault area between reference and test files while precision was evaluated by calculating AMD between captured scans to measure repeatability of scan acquisition. The scan time taken for each participant was also recorded. There was no significant difference in trueness and precision among the groups (P = .806 and .950, respectively). Average scan time for Class I and III palatal vaults was 1 min 13 seconds and 1 min 37 seconds, respectively, while class II deep palatal vaults showed the highest scan time of 5 mins. Palatal vault form in edentulous cases has an influence on scan time. However, it does not have a substantial impact on the accuracy of the acquired scans.

Bioengineered cellulosic paper micro-device for serum albumin detection in clinical range

Chronic Kidney Disease (CKD) is becoming one of the major causes of morbidity and mortalities in 21st century. We have developed a bioengineered cellulosic paper device for the quantification of albumin (ALB) in physiological samples. The paper surface was activated and antibodies specific to target biomarker was immobilized on engineered paper surface. Every step after modification was characterized by FTIR, XPS, SPM and optical analysis. Further, the device model was designed using CAD file, and a 3-D cascade device was fabricated with in-built constant light source to provide proper and controlled environment for in-situ image analysis. After adding the sample on the bioengineered paper, the antigen-antibody reaction takes place, after that addition of dye results in change of color from yellow to blueish-green within 40 s. An optical method was employed for the analysis of the images by recognizing the specific area and the color intensity. Additionally, the immunosensor specificity was evaluated on number of molecules that are usually found in the serum sample. The linear dynamic range of the developed immunosensor has been reported to be 1–60 mg/mL, covering the normal as well as clinical range of ALB in physiological samples with a detection limit of 0.049(±0.002) mg/mL. With good precision and recovery, the device was able to successfully determine the ALB concentrations in serum sample. The developed device has simple and user-friendly interface and it may also help diagnosing CKD in personalized settings.

The ReFiBot makers guide: Fostering academic open science and circularity with a robotic educational kit

The advent of robotics in schools and universities curricula are preparing students to encompass new didactic fields. This article presents ReFiBot which is an education robot that has been used to increase the technical literacy on robotics and bring more awareness to open science at Wageningen University. The ReFiBot combines open-source hardware and software, integrated with a chassis made from recycled plastic from fishnets. The ReFiBot was carefully designed to be easily assembled with off-the-shelf electronic parts and programmed using the Arduino IDE. Moreover, a software library is facilitated to ease its adoption in educational activities from any curricula level. The ReFiBot has been mainly used for education but can also be used for research on swarm robotics. The CAD files, components list, software files, and tutorial within this contribution will guide the reader through the assemblage and best practices of this circular robotics kit.

The effect of selective laser melting process parameters and remelting scanning strategy on relative density and surface hardness of stainless steel 316L

Selective laser melting (SLM) process is the foremost metal additive manufacturing (AM) technology that precisely generates complex geometries from CAD files. Mechanical behavior of printed parts is greatly affected by printing parameters and defining the optimal values of the process parameters to enhance the mechanical properties of components is highly regarded. In this work, four different SLM parameters including scanning speed, laser power, hatch spacing and scan pattern angle were applied to manufacture SS316L parts. For investigating the effect of each parameter and their interactions on hardness and relative density, Taguchi L16 orthogonal array was employed. The influence of part geometry and remelting is also evaluated in order to optimize the hardness and relative density of components. The results exhibited that the laser scanning speed was the most predominant SLM parameter for investigated mechanical properties. Analyzing the regression formula obtained from the results showed that the optimum laser energy density resulted in a 0.37% and 5.38% increase compared to the lowest relative density and hardness, respectively. High remelting energy associated with low remelting scanning speed, caused an 8.5% and 17.9% rise in hardness of squares and triangles, respectively; however, it led 12.5% reduction in hardness for circles. Remelting caused a 2.32% reduction, 2.1% increase and 5.3% rise on relative density for circles, squares and triangles, respectively.

Use of reverse engineering methods in the process of restoration of machine parts

The paper considers the peculiarities of creating digital copies of objects using reverse engineering technology. The main process used in reverse engineering is the processing of digital copies of objects, which is called photogrammetry. The reverse engineering process consists of the following stages. First, a 3D scan of the product and scan data processing is performed. The received digital data (polygonal mesh) is converted into a CAD file, which can be used to change the shape and topology of the model in accordance with the project. Based on this, an analysis of the two main technologies on which photogrammetry is based was performed: 1) laser triangulation method (laser scanners are used), 2) structured light method (optical scanners are used). The main disadvantages of using laser triangulation when scanning machine parts and methods of reducing their negative impact on the final result are given. The process of determining the position of a point when scanning parts by the laser triangulation method is considered in detail. Equations for normalizing the position of the point and equations that remove the distortion of the point due to the aberration of the camera lens are given. An equation for determining the width of a laser beam is presented, on the basis of which its main geometric characteristics are determined. A general diagram of the influence of the main factors on the quality of the process of scanning parts by the method of laser triangulation is constructed. One of the varieties of scanning objects using structured light is the range imaging (SfM) technique. The SfM technique is a process of estimating a three-dimensional structure from a sequence of two-dimensional images that can be associated with local traffic signals. The position of the camera in space is used to find the x,y,z coordinates of each pixel. An overview of the main software for creating and editing a structured polygonal mesh based on scan data is carried out. As a study of the process of reverse engineering technology, a connecting rod of a car engine was scanned by the SfM method and its digital model was created.

Simulation and data processing techniques to design optimized PPR systems on plasma fusion devices

Plasma position reflectometry (PPR) will be used for measuring the plasma position and shape in DEMO. To ensure the reliability, PPR systems are optimized for the expected range of plasmas foreseen during the operation. The study and optimization of PPR systems is a highly demanding computational task and the current approach to define the simulation setup and process the simulation results is time-consuming and does not allow the study of a large number of configurations in useful time.In this article we automate the simulation process required for studying and optimizing PPR systems with the REFMUL family of full-wave FDTD codes. A general overview of the fundamental concepts of PPR systems is presented in the context of reflectometry simulations. Different solutions are proposed to produce realistic reflectometer models from CAD files, realistic plasma models, minimize the complexity of the input definition, manage the simulations in HPCs and analyze the simulation results of PPR systems. A new algorithm based in the In-phase and Quadrature (I/Q) detection scheme is developed to extract the phase derivative and the detected signal amplitude from the synthetic signals of a generic simulation. These techniques allow a brute-force approach to reflectometry problems, being essential for the study of reflectometry systems. The algorithms are validated using the 2017 DEMO baseline scenario to test more than 100 different reflectometers at different poloidal positions in the same toroidal section. The application of our methodology can be extended to different reflectometry techniques and other fields.

Motion Modeling of a 5-Axis Delta Robot with Telescopic Shafts

Abstract This paper deals with motion modeling of a 5-axis industrial Delta robot. The robot has extra rotational two degrees-of-freedom (DoF) realized with a wrist arm driven through two co-axial telescopic shafts as compared to the basic 3-DoF Delta robot. The kinematic model is derived with fully symbolic Jacobian matrices. Using the derived Jacobians, a novel simplified dynamic model is proposed based on the virtual work principle and the trajectory dependent artificial mass distribution. As compared to the existing literature, the proposed dynamic model does not require Lagrangian multiplier calculation or recursive and parallel computing so that it provides advantage for model-based control design. Also a linear regression model is provided to identify the dynamic parameters. The presented models are suitable to be employed for basic Delta and the extended Delta robots with parallel telescopic shafts as well. The derived models are verified through a Simulink model where the 3D CAD files of robot bodies having the information of real dimensions, masses and moments of inertia are used. The adequate agreement of the proposed dynamic model with the simulation results is illustrated via performing three different generated trajectory profiles. We also demonstrate the better accuracy of the proposed dynamic model as compared to a simplified and widely employed model for basic 3-DoF Delta robot. The simulation model is shared online to serve as a research and test platform for performing tasks such as motion planning, model prototyping, and control design.

SLIM Tricks: Tools, Concepts, and Strategies for the Development of Planar Ion Guides.

Traveling wave ion mobility experiments using planar electrode structures (e.g., structures for lossless ion manipulation, TW-SLIM) leverage the mature manufacturing capabilities of printed circuit boards (PCBs). With routine levels of mechanical precision below 150 μm, the conceptual flexibility afforded by PCBs for use as planar ion guides is expansive. To date, the design and construction of TW-SLIM platforms require considerable legacy expertise, especially with respect to simulation and circuit layout strategies. To lower the barrier of TW-SLIM implementation, we introduce Python-based interactive tools that assist in graphical layout of the core electrode footprints for planar ion guides with minimal user inputs. These scripts also export the exact component locations and assignments for direct integration into KiCad and SIMION for PCB finalization and ion flight simulations. The design concepts embodied in the set of scripts comprising SLIM Pickins (PCB CAD generation) and pigsim (SIMION workspace generation) build upon the lessons learned in the independent development of the research-grade TW-SLIM platforms in operation at WSU. Due to the inherent flexibility of the PCB manufacturing process and the time devoted to board layouts prior to manufacturing, both scripts serve to enable rapid, iterative design considerations. Because only a few predefined parameters are necessary (i.e., the TW-SLIM monomer width, x position following a TW Turn, and y position following a TW Turn) it is possible to design the exact component layouts and accompanying simulation space in a manner of minutes. There is no known limitation to the board layout capacities of the scripts, and the size of a designed layout is ultimately constrained by the abilities of the final PCB design and simulation tools, KiCad and SIMION, to accommodate the thousands of electrodes comprising the final design (i.e., RAM and software overhead). Toward removing the barriers to exploring new SLIM tracks and the likelihood of layout errors that require considerable revision and engineering time, the SLIM Pickins and pigsim tools (included as Supporting Information) allow the user to quickly design a length of planar ion guide, simulate its abilities to confine and transmit ions, compare hypothetical board outlines to given vacuum chamber dimensions, and generate a near-production ready PCB CAD file. In addition to these tools, this report outlines a series of cost-saving strategies with respect to vacuum feedthroughs and vacuum chamber design for TW ion mobility experiments using planar ion guides.

Risk factors associated with screw loosening in CAD-CAM custom abutments: A 6-year retrospective study

Statement of ProblemCustom abutments made by using computer-aided design and computer-aided manufacturing (CAD-CAM) are often used for implant-supported prostheses. However, studies on screw loosening of implant prostheses using custom abutments are lacking. PurposeThe purpose of this retrospective study was to investigate the risk factors of screw loosening in implant-supported prostheses using custom abutments made with CAD-CAM. Material and methodsClinical charts, radiographic images, and CAD custom abutment design file data were collected and analyzed retrospectively. The study included 255 patients with 401 dental implants, and the follow-up duration was 6 years. Age, sex (male/female), type of unit (single-unit or multiunit), location of the implant (maxilla or mandible and anterior, premolar, or molar tooth), type of antagonist, and experience of the prosthodontist were reviewed, and implant angulation (mesiodistal and buccolingual), location of the screw access hole (mesiodistal and buccolingual distances from center), and attrition status (none, localized, or generalized) were measured by using a CAD file. The frequencies and percentages of risk factors were evaluated with the Fisher exact test, and the Bonferroni correction was used as a post hoc test. Multiple logistic regression with the Firth method was performed to calculate the odds ratios and their confidence intervals (α=.05). ResultsScrew loosening showed a correlation with the severity of attrition (P<.001). Single-unit prostheses had a higher risk of screw loosening than multiunit prostheses (P<.001). Experience of the prosthodontist (P<.001). Buccolingual angulation of the implant and abutment significantly influenced the incidence of screw loosening (P<.05). Age, sex, location of the implant, type of antagonist, mesiodistal implant angulation, and buccolingual and mesiodistal location of the screw access hole did not significantly influence the incidence of screw loosening (P>.05). ConclusionsThe degree of attrition, buccolingual angulation of the implant and abutment, type of unit, and experience of the prosthodontist (>3 years or <3 years) were risk factors in the incidence of screw loosening.

Challenges and Future Perspectives for Additively Manufactured Polylactic Acid Using Fused Filament Fabrication in Dentistry.

Additive manufacturing (AM), which is also called rapid prototyping/3D printing/layered manufacturing, can be considered as a rapid conversion between digital and physical models. One of the most used materials in AM is polylactic acid (PLA), which has advantageous material properties such as biocompatibility, biodegradability, and nontoxicity. For many medical applications, it is considered as a leading biomaterial. In dentistry, in addition to its uses in dental models (education, teaching, simulation needs), it can be used for therapeutic objectives and tissue engineering. The fused filament fabrication (FFF) technique, also called fused deposition modeling (FDM), is widely used as an AM technique to perform complex and functional geometries directly from CAD files. In this review, the objective was to present the different challenges and future perspectives of this additively manufactured material by using FFF in dentistry areas. Some suggestions for future directions to extend to more dental applications (support structures, lattice structures, etc.) and to consider more criteria (sustainability, uncertainty etc.) will be discussed. Advanced studies such as machine learning (ML) techniques will be suggested to reduce the failure cases when using the additively manufactured PLA by FFF in dentistry.

Defining challenging areas of the preparation finish line by using an open-source 3D modeling computer program: A tip to simplify margin identification by the dental laboratory technician

Intraoral data acquisition and computer-aided design and computer-aided manufacturing (CAD-CAM) systems have simplified and expedited the fabrication of dental prostheses. 1 Van Noort R. The future of dental devices is digital. Dent Mater. 2012; 28: 3-12 Crossref PubMed Scopus (801) Google Scholar ,2 Giuliodori G. Rappelli G. Aquilanti L. Intraoral scans of full dental arches: an in vitro measurement study of the accuracy of different intraoral scanners. Int J Environ Res Public Health. 2023; 20: 4776 Crossref Scopus (0) Google Scholar Contemporary dental CAD-CAM provides the freedom to design and fabricate diverse dental devices, including custom impression trays, surgical templates, and removable and fixed dental prostheses. 1 Van Noort R. The future of dental devices is digital. Dent Mater. 2012; 28: 3-12 Crossref PubMed Scopus (801) Google Scholar ,3 Revilla-León M. Özcan M. Additive manufacturing technologies used for processing polymers: current status and potential application in prosthetic dentistry. J Prosthodont. 2019; 28: 146-158 Crossref PubMed Scopus (217) Google Scholar ,4 Turkyilmaz I. Wilkins G.N. Varvara G. Tooth preparation, digital design and milling process considerations for CAD/CAM crowns: understanding the transition from analog to digital workflow. J Dent Sci. 2021; 16: 1312-1314 Crossref Scopus (8) Google Scholar These dental appliances are created from a digital file that recreates the surface geometry of the target object, typically a standard tessellation language (STL) file. 5 Grant G.T. Campbell S.D. Masri R.M. Andersen M.R. The American college of prosthodontist digital dentistry glossary development task force. Glossary of digital terms. J Prosthodont. 2016; 25: S2-S9 Crossref PubMed Scopus (27) Google Scholar A prerequisite for accurate manufacture is the exact capture and identification of the fine details in the target intraoral structures. An accurate capture can be challenging when the preparation finish line is subgingival, when abundant bleeding or salivation occurs, or when operator scanning skills and speed are still developing. 6 Mangano F. Gandolfi A. Luongo G. Logozzo S. Intraoral scanners in dentistry: a review of the current literature. BMC Oral Health. 2017; 17: 149 Crossref PubMed Scopus (308) Google Scholar Additionally, the location of fine details can be challenging for the dental laboratory technician to visualize when the CAD file is outsourced for the manufacture of the definitive restoration, since STL files lack attributes such as color and texture. 5 Grant G.T. Campbell S.D. Masri R.M. Andersen M.R. The American college of prosthodontist digital dentistry glossary development task force. Glossary of digital terms. J Prosthodont. 2016; 25: S2-S9 Crossref PubMed Scopus (27) Google Scholar These features help differentiate the tooth from its surrounding tissues when finish lines are subgingival or when displacement is limited. The present article presents a straightforward workflow that defines challenging areas of the preparation finish line by using an open-source 3D modeling computer program. This procedure can be used to communicate the finish line observed to the dental laboratory technician when STL files are used to design the definitive restoration and stops the technician guessing the finish line, since the hard-to-see areas are defined by the clinician. Additionally, this approach has advantages over the margin tracing and sculpting tools available in most 3-dimensional (3D) CAD computer programs since it allows selecting the critical areas around the finish line considering the mesh geometry of the 3D file. Visualizing the 3D mesh permits a more precise selection, which can minimize distortion as even the smallest changes in the mesh surface can be observed if transformation or sculpting procedures are used.

Bioabsorbable Polymeric Stent for the Treatment of Coarctation of the Aorta (CoA) in Children: A Methodology to Evaluate the Design and Mechanical Properties of PLA Polymer.

This study presents a methodology that combines experimental tests and the finite element method, which is able to analyse the influence of the geometry on the mechanical behaviour of stents made of bioabsorbable polymer PLA (PolyLactic Acid) during their expansion in the treatment of coarctation of the aorta (CoA). Tensile tests with standardized specimen samples were conducted to determine the properties of a 3D-printed PLA. A finite element model of a new stent prototype was generated from CAD files. A rigid cylinder simulating the expansion balloon was also created to simulate the stent opening performance. A tensile test with 3D-printed customized stent specimens was performed to validate the FE stent model. Stent performance was evaluated in terms of elastic return, recoil, and stress levels. The 3D-printed PLA presented an elastic modulus of 1.5 GPa and a yield strength of 30.6 MPa, lower than non-3D-printed PLA. It can also be inferred that crimping had little effect on stent circular recoil performance, as the difference between the two scenarios was on average 1.81%. For an expansion of diameters ranging from 12 mm to 15 mm, as the maximum opening diameter increases, the recoil levels decrease, ranging from 10 to 16.75% within the reported range. These results point out the importance of testing the 3D-printed PLA under the conditions of using it to access its material properties; the results also indicate that the crimping process could be disregarded in simulations to obtain fast results with lower computational cost and that new proposed stent geometry made of PLA might be suitable for use in CoA treatments-the approach that has not been applied before. The next steps will be to simulate the opening of an aorta vessel using this geometry.

Comparing apples and oranges: Creating a comprehensive view of facility siting risks

AbstractEnsuring that building occupants are safe from the myriad potential hazards in process facilities involves many challenges. Often, a facility siting plan is the result of several disparate studies, conducted years apart, and stitched together to try to form an overall plan. This makes it difficult to find a complete representation of potential impacts on a building, or gauge how changes to operations may impact nearby buildings. Understanding all potential impacts is critical when making investment decisions regarding mitigations of facility siting risks. Many of these challenges can be addressed by creating a single map of the site using a high‐resolution satellite image embedded into a CAD file. By utilizing layering capabilities, contours from individual scenarios can be drawn on individual layers and viewed individually or used together to create an overall map to enable siting of occupied facilities. By having each potential hazard type drawn on a single map, one can quickly evaluate the potential hazards that impact a particular area and see whether a particular potential hazard is dominant. This can help in deciding where to site buildings, whether or not a building occupancy can be increased, evaluation of efficacy of risk mitigation measures, and emergency response efforts.

The design of a family of parametric anatomically-based compliant buttock models to evaluate wheelchair cushion performance.

The evaluation of wheelchair cushion performance is of interest to a variety of stakeholders, including standards organizations, cushion manufacturers, clinicians, users and payers. The objective of this project was to develop a family of compliant buttock models that are based upon the anatomical parameters of persons with varying body sizes. The models are parametrically designed so can be scaled to evaluate different sized cushions. This paper will detail the designs, describe the anatomical basis for the design and provide the rationale for the design decisions. The manuscript also serves a secondary purpose to illustrate how anthropometric data can be applied to the design of anatomical phantoms that reflect both soft tissue and skeletal anthropometry. Supplemental material includes greater detail and the full CAD files and model fabrication instructions are available in an open access repository for persons who wish to fabricate the models.

Development of Application for Airfoil Generation and Testing

Abstract: CAD automation works by utilizing tools and technology to increase the speed at which a design is completed. The CAD workflows that you set up can be carried out over and over again much like any other repetitive task in your office. This allows for multiple designs to be completed with reduced effort, freeing up valuable time for more important tasks and creativity. The application devloped automates the processes required to create an 3D part file of any airfoil.The application also provides a script to automate the next step i.e CFD analysis of the airfoil. The application is divided in 4 major parts according to the task automated. In the first section , the user can enter the parameters of desired airfoil,these parameters are then utilized by the software to create coordinates of the points that lie on airfoil. After this a curve is fitted to the airfoil points and the coefficients of the fitted curve are displayed and stored. In the section , the coefficients generated in the first section are utilized to generate CAD files of the airfoil. In the third section the software provides a python script that automates the task of carrying out the CFD simulation of airfoil. Lastly the “results” section provides a workspace to analyze the output of CFD simulation. Thus the application acts as a complete workstation for design life cycle of the airfoil.

Comparison of 3D Sensors for Automating Bolt-Tightening Operations in the Automotive Industry.

Machine vision systems are widely used in assembly lines for providing sensing abilities to robots to allow them to handle dynamic environments. This paper presents a comparison of 3D sensors for evaluating which one is best suited for usage in a machine vision system for robotic fastening operations within an automotive assembly line. The perception system is necessary for taking into account the position uncertainty that arises from the vehicles being transported in an aerial conveyor. Three sensors with different working principles were compared, namely laser triangulation (SICK TriSpector1030), structured light with sequential stripe patterns (Photoneo PhoXi S) and structured light with infrared speckle pattern (Asus Xtion Pro Live). The accuracy of the sensors was measured by computing the root mean square error (RMSE) of the point cloud registrations between their scans and two types of reference point clouds, namely, CAD files and 3D sensor scans. Overall, the RMSE was lower when using sensor scans, with the SICK TriSpector1030 achieving the best results (0.25 mm ± 0.03 mm), the Photoneo PhoXi S having the intermediate performance (0.49 mm ± 0.14 mm) and the Asus Xtion Pro Live obtaining the higher RMSE (1.01 mm ± 0.11 mm). Considering the use case requirements, the final machine vision system relied on the SICK TriSpector1030 sensor and was integrated with a collaborative robot, which was successfully deployed in an vehicle assembly line, achieving 94% success in 53,400 screwing operations.

CAD files for 3D printed sediment feed; .stl, .step, and .f3d files included

CAD files for 3D printed sediment feed; .stl, .step, and .f3d files included

Specifications and pre-production of n+-in-p large-format strip sensors fabricated in 6-inch silicon wafers, ATLAS18, for the Inner Tracker of the ATLAS Detector for High-Luminosity Large Hadron Collider

The ATLAS experiment is constructing new all-silicon inner tracking system for HL-LHC. The strip detectors cover the radial extent of 40 to 100 cm. A new approach is adopted to use p-type silicon material, making the readout in n+-strips, so-called n+-in-p sensors. This allows for enhanced radiation tolerance against an order of magnitude higher particle fluence compared to the LHC. To cope with varying hit rates and occupancies as a function of radial distance, there are two barrel sensor types, the short strips (SS) for the inner 2 and the long strips (LS) for the outer 2 barrel cylinders, respectively. The barrel sensors exhibit a square, 9.8 × 9.8 cm2, geometry, the largest possible sensor area from a 6-inch wafer. The strips are laid out in parallel with a strip pitch of 75.5 μm and 4 or 2 rows of strip segments. The strips are AC-coupled and biased via polysilicon resistors. The endcap sensors employ a “stereo-annulus” geometry exhibiting a skewed-trapezoid shapes with circular edges. They are designed in 6 unique shapes, R0 to R5, corresponding to progressively increasing radial extents and which allows them to fit within the petal geometry and the 6-inch wafer maximally. The strips are in fan-out geometry with an in-built rotation angle, with a mean pitch of approximately 75 μm and 4 or 2 rows of strip segments. The eight sensor types are labeled as ATLAS18xx where xx stands for SS, LS, and R0 to R5. According to the mechanical and electrical specifications, CAD files for wafer processing were laid out, following the successful designs of prototype barrel and endcap sensors, together with a number of optimizations. A pre-production was carried out prior to the full production of the wafers. The quality of the sensors is reviewed and judged excellent through the test results carried out by vendor. These sensors are used for establishing acceptance procedures and to evaluate their performance in the ATLAS collaboration, and subsequently for pre-production of strip modules and stave and petal structures.