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Abstract Soft actuators with pneumatic network have innovative potential applications in medical and rehabilitation areas. The performance of this kind of actuators is determined by the design of chambers and the properties of the active extensible layer and the passive inextensible layer. In this article, actuator with isosceles trapezoidal chambers is proposed. Orthogonal experiment design and finite element method are used to optimize the structure of actuators. Results indicate that adding constrain-limiting paper in the passive layer can significantly reduce the bending radius. Position of the paper in the passive layer also affects the bending radius. Actuators with trapezoidal chambers can have a smaller bending radius compared with that with rectangle chambers. The bending radius decreases as the ratio of short base to long base of trapezoid decreases. Increasing the number density of chambers can further reduce the bending radius.

Nikola Tesla in the year 1920 invented a new type of one-way valve, without any moving parts. He made this possible, by virtue of the geometry of the fluid path. In this work, we have optimised the design made by Tesla and increased its efficiency. Today, these valves are used in micro-fluidic systems, pulsating heat pipes, spacecraft propulsion systems etc. Apart from this, we have found that this valve can also be used in the Intra-venous fluid administration system and also in suppressors of guns. In the IV system, the valve can be used to address the reverse blood flow issue. In suppressors, the valve can reduce the pressure of hot gas coming from the gun which in turn reduces the sound made by the gun. Computational fluid dynamics (CFD) simulation was done using fluid analysis software. From CFD analysis it was observed that the efficiency of the optimised valve has increased 2 times as compared to the original tesla valve.

To improve the biofidelity of the currently available Hybrid III 10-year-old (HIII-10C) Anthropomorphic Test Device (ATD), the National Highway Traffic Safety Administration (NHTSA) has developed the Large Omnidirectional Child (LODC) ATD. The LODC head is a redesigned HIII-10C head with mass properties and modified skin material required to match pediatric biomechanical impact response targets from the literature. A dynamic, nonlinear finite element (FE) model of the LODC head has been developed using the mesh generating tool Hypermesh based on the three-dimensional CAD model. The material data, contact definitions, and initial conditions are defined in LS-PrePost and converted to LS-Dyna solver input format. The aluminum head skull is stiff relative to head flesh material and was thus modeled as a rigid material. For the actual LODC, the head flesh is form fit onto the skull and held in place through contact friction.

Under body blast (UBB) loading to military transport vehicles is known to cause foot-ankle fractures to occupants due to energy transfer from the vehicle floor to the feet of the soldier. The soldier posture, the proximity of the event with respect to the soldier, the personal protective equipment (PPE) and age/sex of the soldier are some variables that can influence injury severity and injury patterns. Recently conducted experiments to simulate the loading environment to the human foot/ankle in UBB events (~5ms rise time) with variables such as posture, age and PPE were used for the current study. The objective of this study was to determine statistically if these variables affected the primary injury predictors, and develop injury risk curves. Fifty below-knee post mortem human surrogate (PMHS) legs were used for statistical analysis. Injuries to specimens involved isolated and multiple fractures of varying severity.

Finite Element Analysis (FEA) is a powerful and well recognized tool used in the analysis of heat transfer problems. However, FEA can only analyze solid bodies and, by necessity thermal analysis with FEA is limited to conductive heat transfer. The other two types of heat transfer: convection and radiation must by approximated by boundary conditions. Modeling all three mechanisms of heat transfer without arbitrary assumption requires a combined use of FEA and Computational Fluid Dynamics (CFD).

Finite Element Analysis (FEA) has been an indispensable tool for design simulation for several decades but this wide spread use has been limited to simple types of analyses. Relatively recently, more advanced analyses have given easy-to-use interfaces enabling design engineers to simulate problems formerly reserved for analysts. FEA Beyond Basics targets the FEA users who wish to explore those advanced analysis capabilities. It will demonstrate how to move past the ubiquitous linear structural analysis and solve structural nonlinear problems characterized by nonlinear material, large displacements, buckling or nonlinear connectors.

The “Integrated Wheelchair Bed” is an innovative assistive technology designed to address the unique needs of individuals with mobility challenges. This duality concept is born out of a deep understanding of the daily challenges faced by those who require mobility aids for transportation and also need to rest periodically throughout the day, allowing for seamless transitions between mobility and rest. This dichotomy promotes both physical well-being and emotional independence, enhancing the overall quality of life for users. The need for a new wheelchair bed hybrid arises from evolving user requirements, such as improved comfort, compactness, customization, safety, technology integration, cost-efficiency, durability, versatility, aesthetics, healthcare integration, and sustainability. To overcome these problems, we have proposed a wheelchair that can be transformed into a bed using a two-bar linkage with a slot lock mechanism.

The Fundamentals of Geometric Dimensioning and Tolerancing 2018 Using Critical Thinking Skills by Alex Krulikowski reflects the technical content found in the latest release of the ASME Y14.5-2018 Standard. This book includes several key features that aid in the understanding of geometric tolerancing. Each of the textbook's 26 chapters focuses on a major topic that must be mastered to be fluent in the fundamentals of GD&T. Each topic includes a goal that is defined and supported by a set of performance objectives that include real-world examples, verification principles and methods, and chapter summaries. There are more than 260 performance objectives that describe specific, observable, measurable actions that the student must accomplish to demonstrate mastery of each goal. Learning is reinforced by completing three types of exercise problems, along with critical thinking questions that promote application of GD&T on the job.

This interactive eLearning GD&T training course now utilizes HTML5 for better browser and device compatibility. It contains 29 robust, self-paced learning modules that explain the terms, symbols, modifiers, rules, and basic concepts of geometric tolerancing as prescribed in the ASME Y14.5-2009 Standard. Progress is easily measured with instant feedback throughout each lesson that reinforces and aids in concept retention, allowing the learner to determine where further review may be needed. Full color detailed animations that help particpants clearly visualize concepts, along with audio narration and 3D solid part examples.

This interactive eLearning GD&T training course now utilizes HTML5 for better browser and device compatibility. It contains 23 robust, self-paced learning modules that explain the terms, symbols, modifiers, rules, and basic concepts of geometric tolerancing as prescribed in the ASME Y14.5-2018 Standard. Progress is easily measured with instant feedback throughout each lesson that reinforces and aids in concept retention, allowing the learner to determine where further review may be needed. Full color detailed animations that help participants clearly visualize concepts, along with audio narration and 3D solid part examples.

Laser Detecting Systems Enhancing Survivability and Lethality on the Battlefield Designing With Plastics for Military Equipment Engine Air-Brakes Paving the Way to Quieter Aircraft Nett Warrior Enhancing Battlefield Connectivity and Communications XPONENTIAL 2018 - An AUVSI Experience Communications in Space: A Deep Subject First Air-Worthy Metal-Printed RF Filter Ready for Takeoff Validation of Automated Prediction of Blood Product Needs Algorithm Processing Continuous Non-Invasive Vital Signs Streams (ONPOINT4) Using a combination of non-invasive sensors, advanced algorithms, and instruments built for combat medics could reduce hemorrhaging and improve survival rates. Calculation of Weapon Platform Attitude and Cant Using Available Sensor Feedback Successful development of mobile weapon systems must incorporate operation on sloped terrain.

Additive manufacturing (AM), is a manufacturing process of choice for functional part production, adding to the suite of choices a designer has available when designing a part for manufacturing. Like other traditional processes like casting and machining, AM has its set of constraints. An added layer of complexity comes from the fact that there are several different AM processes, and some of the design constraints are process-specific. On the other hand, AM offers a range of opportunities in design freedom and mass customization as well as in cost and lead time reduction in some cases.

This 3-day Fundamentals of GD&T course provides an in-depth study of the terms, rules, symbols, and concepts of geometric dimensioning and tolerancing, as prescribed in the ASME Y14.5-2009 Standard. The course can be conducted in three 8-hour sessions or with flexible scheduling including five mornings or five afternoons. 

This 2-day foundational-level course builds on geometric dimensioning and tolerancing fundamentals and teaches an introduction of how to inspect GD&T requirements.  The course offers an explanation of the geometric symbols, rules, and concepts, the datum system, and how to inspect GD&T requirements using tools from the four categories of inspection tools (CMM; comparison instruments and fixed gages; hand tools and open set up; and production gaging systems).

This course teaches the thought processes involved in assigning GD&T to components, and it changes the way many engineers think about part tolerancing. The course focuses on what constitutes good and poor drawing practices, common dimensioning methods used in industry, using GD&T to communicate system functions on component dimensions, and the logic of how to apply GD&T to components. You’ll also learn how to select datum features and how to fully define component surfaces using GD&T. Establishing tolerance values is not covered.   

This 3-day advanced-level Fundamentals of GD&T course is an in-depth study of the terms, rules, symbols, and concepts of geometric dimensioning and tolerancing as prescribed in the ASME Y14.5M-1994 Standard. The course can be conducted in three 8-hour sessions or with flexible scheduling including five mornings or five afternoons.  This class includes all the content from the Fundamentals of GD&T 2-day foundational course: an explanation of geometric symbols, including each symbol’s requirements, tolerance zones, and limitations.

This course is offered in China only and presented in Mandarin Chinese. The course materials are bilingual (English and Chinese). As the complexity of products increases, traditional text-based systems engineering can no longer meet the needs. To solve the problem, Model-based Systems Engineering offers a unified communication platform among relevant staff by carrying out diagram-based unambiguous description, analysis and design for the demand, and structure and behavior of complex systems in the form of a model.

Use of Model-Based Systems Engineering (MBSE) has been growing across industry, extending beyond defense and aerospace to include various commercial enterprises such as automotive and healthcare. Tool vendors are quick to point out benefits of this model-based approach and practices but are not always clear how MBSE benefits can be realized on a project. When deployed successfully, several key considerations should be addressed that maximize the value for a use-case. This four-hour class will discuss the nature and purpose of the MBSE approach and how key information is used for successful MBSE deployment as it relates to Systems Management.

Led by our senior GD&T professionals with a wide variety of industry background and experience, this one-day GD&T Review and Application course is designed for organizations who have participated in training through SAE but are looking for further clarification on how to apply GD&T best practices to specific organizational drawings. Designed to assist your design teams with highly complex design analysis problems and to support your teams through real world drawing examples, the instructor will review, answer questions, and provide feedback on tolerance analysis and GD&T implementation.

This two-day foundational-level course teaches Advanced Concepts of GD&T as prescribed in the ASME Y14.5-2009 Standard. It offers an explanation of complex GD&T topics, such as the expanded use of composite position and profile tolerances, customized datum reference frames, the translation modifier, and applying GD&T to non-rigid parts. You’ll learn about functional dimensioning, form controls, the datum system, additional and complex datum feature types, expanded datum target concepts and usage on restrained parts, simultaneous, and separate requirements.