Parametric Technology Corporation Research Articles

Development of an unmanned ground vehicle for seed planting

As global population growth intensifies the demand for sustainable food production, the application of robotics to agriculture emerges as a promising solution. This research focuses on the design, development, and deployment of an unmanned ground vehicle for seed planting, also known as a robotic seed planter. The robotic seed planter automates seed planting processes, offering advantages such as increased accuracy, reduced labour requirements, and optimal resource usage. Parametric Technology Corporation (PTC) Creo was used for the structural design, Proteus 8.14 for the circuitry design, and Arduino IDE 2.0 with Visual Studio Code for the programming. The design incorporates seed metering and drilling mechanisms guided by intelligent systems. Results show exceptional accuracy in seed placement (94%), operational efficiency, and adaptability to diverse conditions, with energy consumption relatively low. The planter is equipped with a web application for remote monitoring and control. The application is hosted on one of the microcontrollers and WebSockets protocol is utilized for inter-microcontroller communication. It offers an auto mode for automated planting and Manual mode for easier manoeuvrability. The findings of this study demonstrate the robotic seed planter’s transformative impact on precision agriculture, providing a glimpse into the future of efficient and sustainable farming operations.

Comparative evaluation of variations in torque expression in maxillary incisor and canine using different bracket prescriptions placed at different crown levels by finite element (FE) method: An in-vitro analysis.

While using preadjusted brackets, the position of the bracket on the crown is one of the deciding factors that determine the tooth's final tip, torque, height, and rotation. The final tooth position is not optimal if the bracket is placed incorrectly or if the varying crown morphology does not correspond with the bracket design. The present study was conducted to evaluate and compare the variations in torque expression in maxillary incisor and canine using different bracket prescriptions placed at different crown levels by finite element method. For the present study, three-dimensional models of maxillary right central incisor and canine were made using CREO version 4.0 software. CREO is a powerful three-dimensional (3-D) computer-based, computer-aided design (CAD) software developed by Parametric Technology Corporation (PTC) to aid in design processes. Simulation was done to replicate the clinical situation of an active palatal root torque acting on the incisor and canine. The induced palatal movement of root tips and labial movement of crowns tips, overall stress, and von Mises stress generated in the brackets and the total equivalent strains developed in the periodontal ligament (PDL) were calculated, while the values obtained were tabulated and subjected to statistical analysis. Based on the findings of the present study, the average maximum stress produced in the bracket was calculated as 265.069 Mpa in incisor and 166.742 Mpa in the canine. Likewise, the average of the maximum displacement of root apex observed in the present study was calculated as 0.01401 mm in the incisor and 0.00421 mm in the canine, while the average strain developed in the PDL was calculated as 0.0587 for incisor and 0.0498 for the canine. Furthermore, it was, also, observed that the magnitude of strain developed in the PDL increased with increase in the stress produced by the bracket prescription for both incisor and canine. Within the limitations of the present study, it was concluded that the magnitude of displacement of root apex was significantly influenced by bracket prescription and bracket position. Also, the stress developed in the bracket was influenced by bracket prescription and position, while the variation in crown morphology in the incisor and canine played a significant role in the eventual strain developed in the PDL after torque application.

Isotherm Theoretical Study of the AlxGa1-xAsySb1-y Quaternary Alloy Using the Regular Solution Approximation for Its Possible Growth via Liquid-Phase Epitaxy at Low Temperatures.

This work presents the theoretical calculation of isotherm diagrams for quaternary alloys of III-V semiconductor compounds with the form IIIxIII1-xVyV1-y. In particular, the isotherm diagrams for the AlxGa1-xAsySb1-y quaternary alloy at low temperatures were calculated (500 °C, 450 °C, 400 °C, and 350 °C). The AlxGa1-xAsySb1-y quaternary alloy was formed from four binary compounds such as GaAs, AlAs, AlSb, and GaSb, all with direct bandgaps. The regular solution approximation was used to find the quaternary isotherm diagrams, represented in four linearly independent equations, which were solved using Parametric Technology Corporation Mathcad 14.0 software for different arsenic and antimony atomic fractions. The results support the possible growth of layers via liquid-phase epitaxy in a range of temperatures from 500 °C to 350 °C, where the crystalline quality could be improved at low temperatures. These semiconductor layers could have applications for optoelectronic devices in photonic communications, thermophotovoltaic systems, and microwave devices with good crystalline quality.

An approach to the quantitative determination of endogenous substances in biological fluids by a chromatographic method using a mathematical apparatus

Relevance of the study: The quantification of endogenous substances is an important task in experimental and clinical pharmacology. In the case of working with endogenous compounds, certain difficulties arise. The main one is the impossibility of obtaining the same biomatrix without endogenous compounds for use as standard solutions in the construction of calibration curves. Purpose: The aim of our study was to develop a mathematical methodology for calculating the concentration of endogenous compounds in biological objects measured by chromatography, which allows us to obtain a statistically reliable interval estimation of the concentration of endogenous compounds. Materials and methods: To implement the computational part of the proposed algorithm, the Mathcad engineering calculation program version 15.0 from PTC (Parametric Technology Corporation) is used, which operates under the family of Windows operating systems (XP, 7, Vista, 8). Main results: A mathematical methodology has been developed for calculating the concentration of endogenous compounds in biological objects measured by chromatography, which allows one to obtain a statistically reliable interval estimate of the concentration of endogenous compounds. A feature of this technique is the use of an exclusively analyzed bioobject for quantitative determination of endogenous substances, without the use of so-called “pure” bioobjects for calibration curves, as well as expensive deuterated analogs of markers – substrates of CYP450 isoenzymes and their metabolites. This allows you to maintain the original biomatrix effect when removing the chromatogram. A statistical apparatus is also used to eliminate possible gross errors. To confirm the reliability of the developed method of quantitative determination, the convergence of the results obtained by this method using deuterated standards is established. Conclusions: A mathematical methodology has been developed for calculating the concentration of endogenous compounds in biological objects measured by chromatography, which allows one to obtain a statistically reliable interval estimate of the concentration of endogenous compounds. A feature of this technique is the use of only the analyzed bioobject for quantitative determination of endogenous substances, which allows you to maintain the original biomatrix effect when removing the chromatogram.

Selecting Test Cases for Mechatronic Products with a Variant and Version Management Approach based on a Consistent Toolchain

The number of variants and versions for mechatronic products increases. The high variability poses a challenge for test engineers in selecting suitable test cases upon a change. If a requirement or a feature of a mechatronic product changes, it is not necessary to retest the whole product but only the changed parts. To identify the product features that are directly or indirectly affected by the change, a connection of test, requirement, and variant management is necessary. Therefore, an approach to select test cases based on an occurred change using variant and version knowledge is needed. In this paper, such an approach and its possible application in a toolchain are introduced. The toolchain is built by combining established tools developed by the Parametric Technology Corporation (PTC) that are already used to manage parts of the product life cycle. The resulting PTC Integrity Toolchain and the applicability of the concept on it were evaluated together with industrial experts with positive results.

Calculation of sealing joints with elastic edge in PTC MathCAD

The article touches upon the issues of the development of engineering methods of calculating a thin-walled shell-plate seat for valve and flange sealing joints, followed by the formulation of tasks using modern automated calculation software. To achieve the purpose, the authors used Parametric Technology Corporation MathCAD (PTC MathCAD) with subroutines for the search for extremum of functions and the computational block ‘Given - minimize’. The calculation is presented in the form of algorithms consisting of three logically interrelated parts: 1) stiffness calculation; 2) strength calculation; 3) the calculation of rational dimensions. The obtained results of the calculation of geometric dimensions are tested, which eliminates a probable error in the calculated block ‘Given’ of PTC MathCAD. Among the developed engineering methodologies, the article describes the following ones: a method for calculating the rational geometrical dimensions of a shell-plate valve seat, operating under shock loading at an uncertain maximum dynamic load. It ensures that the allowable stresses in a thin-walled shell-plate seat are not exceeded. Another is a method for testing the stress-strain state of a shell-plate valve seat under static loading with a force of sealing and pressure of the working medium. The last one is the method of calculating rational geometrical dimensions of the shell-plate seat of a flange connection, which minimizes the unit stiffness (minimizing sealing force), provided that the shell-plate seat strength is ensured.

Comparative effect of implant-abutment connections, abutment angulations, and screw lengths on preloaded abutment screw using three-dimensional finite element analysis: An in vitro study.

Purpose:The purpose of this study is to compare the effect of implant-abutment connections, abutment angulations, and screw lengths on screw loosening (SL) of preloaded abutment using three dimensional (3D) finite element analysis.Materials and Methods:3D models of implants (conical connection with hex/trilobed connections), abutments (straight/angulated), abutment screws (short/long), and crown and bone were designed using software Parametric Technology Corporation Creo and assembled to form 8 simulations. After discretization, the contact stresses developed for 150 N vertical and 100 N oblique load applications were analyzed, using ABAQUS. By assessing damage initiation and shortest fatigue load on screw threads, the SL for 2.5, 5, and 10 lakh cyclic loads were estimated, using fe-safe program. The obtained values were compared for influence of connection design, abutment angulation, and screw length.Results:In straight abutment models, conical connection showed more damage (14.3%–72.3%) when compared to trilobe (10.1%–65.73%) at 2.5, 5, and 10 lakh cycles for both vertical and oblique loads, whereas in angulated abutments, trilobe (16.1%–76.9%) demonstrated more damage compared to conical (13.5%–70%). Irrespective of the connection type and abutment angulation, short screws showed more percentage of damage compared to long screws.Conclusions:The present study suggests selecting appropriate implant-abutment connection based on the abutment angulation, as well as preferring long screws with more number of threads for effective preload retention by the screws.

Product lifecycle management in design and engineering education: International perspectives

Technological advances in the last decade have influenced changes in the design and engineering industries on a global scale. Lean and collaborative product development are approaches increasingly adopted by the industry and seen as the core of product lifecycle management. These trends have created the need for new skilled professionals, and universities should adapt their curricula in response. There is an increased need for academia to work with industry in order to meet these challenges. This article reports on the Parametric Technology Corporation Academic Research Symposium held in April 2011. The topics were centred around understanding the essence of product lifecycle management and its impact on design and engineering education. Furthermore, examples of implementing product lifecycle management and collaborative practices in higher education were presented from the United States and France. This article concludes with a discussion of the recommendations made at the symposium for the future development and support of key skills across university curricula.

An Expert System for 2D Stress Analysis of Human Teeth

The concepts of rapidly and automatically obtaining the stresses found in specific human teeth and performing quick parametric studies has been a persistent goal in bioengineering. Finite element analysis (FEA) is a powerful approach for human tooth stress analysis and has been applied to various dental researches. However, the whole FEA process is a major challenge to dental researchers since special simulation skills and expert knowledge in mechanics are required for constructing proper models and obtaining accurate results. This paper presents an expert system that permits dentists with no engineering expertise to obtain stress distributions accurately and rapidly for various dental applications. The expert system for 2D stress analysis of human teeth is developed on the customization platforms provided by commercial computer aided design (CAD) software (ProEngineer Wildfire 3.0, Parametric Technology Corporation, Needham, MA, USA) and FEA software (MD Patran R2, MSC Software Corporation, CA, USA), respectively. A knowledge based system is built for helping users carry out the whole FEA process automatically. Graphical user interfaces (GUIs) are constructed for inputting the necessary tooth information such as dimensions, material properties, etc. An orthodontic application is presented for showing how the expert system works. The approaches developed and applied here can be expanded to provide automatic stress analyses for many other applications as well.

Stress distribution among periodontally compromised abutments: A comparative study using three-dimensional finite element analysis

Aims:The aim of the study was to evaluate the stress distribution patterns in teeth and supporting structures of fixed prosthesis and design modifications in a fixed prosthesis with either normal or reduced bone support of an additional abutment. Study was also undertaken to disprove Ante's law.Materials and Methods:Main models and variations of main models (modification 1, 2, 3, 4, 5, 6, 7, 8) were subjected to 200 N at angulations of 90° and 15° on functional cusps. Results for each loading were obtained as stress distribution color images and numerical values were recorded. A three-dimensional finite element analysis study of variations of normal models was performed using two finite element softwares, namely PRO-Engineer wildfire version 1.0 manufacturer: Parametric technology corporation, Needham, MA 02494 U.S.A.Results:When periodontal compromised abutment teeth was splinted with an additional abutment an increase of stress was observed in periodontally compromised abutments so an additional abutment is not required. Eventhough the pericemental area of compromised abutments with an additional abutment (canine) was more than the combined pericemental area of pontics to be replaced, stress generated was more on abutments. This disproves Ante's law. Hence, it may be a reference, but should not be the ultimate criterion in determining the number of multiple abutments.Conclusions:When periodontal compromised abutment teeth was splinted with an additional abutment an increase of stress was observed in periodontally compromised abutments so an additional abutment is not required. Even though the pericemental area of compromised abutments with an additional abutment (canine) was more than combined pericemental area of pontics to be replaced, stress generated was more on abutments. This disproves Ante's law. Hence, it may be a reference, but should not be the ultimate criterion in determining the number of multiple abutments.

AUTOLAY – a GUI-based design and development software for laminated composite components

The advantage of directional property and tailoring concepts, in addition to other mechanical properties, offered by the composite material allows the designer to conceive innovative designs with desired response characteristics. However, the process of converting the optimization output of complex composite components into a reliable manufacturable product has remained a laborious and painstaking effort leading to large cycle times resulting in reduced cost effectiveness. The drudgery involved in the manual route and the demand to deliver the product meeting the time target in a project environment can often result in compromised solution with no scope for alternate and better design. To circumvent this lacuna in the design and development process there has been constant efforts for automation in the industry to achieve the full potential benefits of the composite technology. The development of a GUI-based software system AUTOLAY for the design of laminate composite components is a step in that direction. An integrated design and manufacturing approach has been used in AUTOLAY to realize the full potential benefits of laminate composite components. The software has been integrated with Parametric Technology Corporation’s CAD software CADDS5.