Papers by Spencer Magleby
CRC Press eBooks, Jun 6, 2023
Flexible segments present challenges to prototyping compliant mechanisms. This paper discusses me... more Flexible segments present challenges to prototyping compliant mechanisms. This paper discusses methods for prototyping compliant mechanisms, including use of 3-axis CNC milling, laser cutting, and wire EDM. Rapid prototyping methods and hybrid methods are also discussed. A method for machining living hinge prototypes with good fatigue life is also documented.
<jats:title>Abstract</jats:title> <jats:p>Most engineering design is performed ... more <jats:title>Abstract</jats:title> <jats:p>Most engineering design is performed by teams. Team formation from a pool of competent designers and engineers is an important factor in helping determine performance potential. This paper is proposes a framework that we have developed to help guide research, and highlights challenges and obstacles that must be addressed in order to improve results in team formation research. A basic framework is presented and used as a basis for reviewing past work in team formation studies. This framework is then expanded to include explicit decisions about team formation and experimental strategy. Three important aspects of the framework that are critical to obtaining significant results about team formation are discussed: experimental strategy, success measures, and the separation of team formation effects from environmental effects. Recommendations for improvement in these areas are presented.</jats:p>
Mechanical Sciences, Nov 15, 2013
Pop-up paper mechanisms use techniques similar to the well-studied paper folding techniques of or... more Pop-up paper mechanisms use techniques similar to the well-studied paper folding techniques of origami. However, pop-ups differ in both the manner of construction and the target uses, warranting further study. This paper outlines the use of planar and spherical kinematics to model commonly used pop-up paper mechanisms. A survey of common joint types is given, including folds, interlocking slots, bends, pivots, sliders, and rotating sliders. Also included is an overview of common one-piece and layered mechanisms, including single-slit, double-slit, V-fold, tent, tube strap, and arch mechanisms. Each mechanism or joint is shown using both a paper representation and either a rigid-body or pseudo-rigid-body representation. In addition, this paper shows that more complex mechanisms may be created by combining simple mechanisms in various ways. The principles presented are applied to the creation of new pop-up joints and mechanisms. The new mechanisms employ both spherical and spatial kinematic chains. Understanding pop-up mechanism kinematics could lead to new applications in deployable structures, packaging, and instruments for minimally invasive surgery.
Journal of Medical Devices-transactions of The Asme, Jun 27, 2017
This work exploits the advantages of compliant mechanisms (devices that achieve their motion thro... more This work exploits the advantages of compliant mechanisms (devices that achieve their motion through the deflection of flexible members) to enable the creation of small instruments for minimally invasive surgery (MIS). Using flexures to achieve motion presents challenges, three of which are considered in this work. First, compliant mechanisms generally perform inadequately in compression. Second, for a 690 deg range of motion desired for each jaw, the bending stresses in the flexures are prohibitive considering materials used in current instruments. Third, for cables attached at fixed points on the mechanism, the mechanical advantage will vary considerably during actuation. Research results are presented that address these challenges using compliant mechanism principles as demonstrated in a two-degree-of-freedom (2DoF) L-Arm gripper.
Precision Engineering-journal of The International Societies for Precision Engineering and Nanotechnology, 2018
The cylindrical cross-axis flexural pivot (CCAFP) is proposed as an ultracompact flexure capable ... more The cylindrical cross-axis flexural pivot (CCAFP) is proposed as an ultracompact flexure capable of being integrated into hollow cylindrical shafts, enabling shaft motion without inhibiting cables or other components inside the shaft. Mechanism geometry, materials, and manufacturing are proposed and the results analyzed and tested. A parametric finite element model of the CCAFP was created to analyze the force-deflection and strain-deflection relationships and the predicted behavior was verified by experiment. Analytic models of stress-limiting cam-surfaces suggest even larger motions may be possible when not limited by current practical constraints. The CCAFP is demonstrated and tested at multiple size scales and in multiple materials, ranging from 28.6 mm diameter 4130 steel (achieving 9 degrees of angular deflection) to 3 mm diameter NiTi (achieving an angular deflection of 85 degrees). The results are generalized to apply to a range of applications, and the CCAFP particularly shows promise for implementation in minimally invasive surgical instruments to decrease instrument size while maintaining instrument performance.
Journal of Mechanisms and Robotics, May 1, 2015
This paper presents a method for fabricating millimeter-scale robotic components for minimally in... more This paper presents a method for fabricating millimeter-scale robotic components for minimally invasive surgery. Photolithographic patterning is used to create a framework of carbon nanotubes (CNTs) that can be infiltrated with a variety of materials, depending on the desired material properties. For the examples shown in this paper, amorphous carbon is used as the infiltration material. The planar frameworks are then stacked to create the 3D device. The detail and precision are affected by large changes in cross section in the direction of stacking. Methods for improving the definition of the 3D object due to changing cross section are discussed. The process is demonstrated in a two-degree-of-freedom (2DOF) wrist mechanism and a 2DOF surgical gripping mechanism, which have the potential of decreasing the size of future minimally invasive surgical instruments.
Volume 7: 46th Mechanisms and Robotics Conference (MR)
This paper presents a systematic approach for selecting an origami source pattern for deployable ... more This paper presents a systematic approach for selecting an origami source pattern for deployable space array applications, followed by two case studies used to demonstrate the selection process. Applying origami principles to form engineering solutions can be a difficult task. Competing requirements may create confusion around which pattern is most favorable for the space array application. As a result, this paper aims to provide clarity on the process needed to effectively design an origami space array. The focus of this paper is to provide aerospace engineers and designers with a framework for identifying optimal origami source patterns for space array applications.
Volume 7: 46th Mechanisms and Robotics Conference (MR)
Design projects in childcare settings present unique design challenges because of their function,... more Design projects in childcare settings present unique design challenges because of their function, size, and specific safety concerns. In selecting effective childcare furniture, stowage space, safety, and ease of access for childcare furniture are important considerations. Origami-inspired design can be useful in addressing these issues in an innovative way by introducing flat-foldability and deployability into childcare furniture. Fundamental design considerations for childcare furniture and mechanical design principles for deployable furniture are examined in order to understand how to make safe and functional furniture pieces. Childcare furniture must be very child-safe. This means that origami principles used must not add safety concerns like decreased stability or pinch points. Nonhazardous, durable, and comfortable materials must be used. Extra precaution must be taken when designing folding structures for use in a childcare environment. Mechanical principles for such systems,...
Volume 5B: 41st Mechanisms and Robotics Conference
The mechanical properties of origami tessellations may provide innovative new designs for energy ... more The mechanical properties of origami tessellations may provide innovative new designs for energy absorbing applications. The elastic energy absorbing properties of a particular tesselation, the Miura-ori, is investigated. Analytical models for the kinematics and force-deflection of a unit cell based on two different modes of elastic energy absorption are derived. The force-deflection model is developed based on the application of compliant mechanism theory and virtual work analysis. The models are verified through comparison with published results for similar models, analysis using commercial kinematics software and comparison to physical testing. Physical prototypes are used to determine values stiffness terms. The analytical models are used to explore the effects of the key geometrical parameters of the tessellation. This work lays a foundation for the use of origami-based corrugations in elastic energy absorption applications.
Mechanism and Machine Theory
<jats:title>Abstract</jats:title> <jats:p>To achieve superior product and proce... more <jats:title>Abstract</jats:title> <jats:p>To achieve superior product and process designs with "typical" engineering students requires careful attention to the design process that is taught and the teaching methods to be followed. The Integrated Product and Process Design (or Capstone) program at BYU has applied both. The Capstone program has been in operation for four years, with over 300 students having been through the program, and over 60 projects sponsored by industry.</jats:p> <jats:p>The design process taught in Capstone starts with a rapid cycle through to preliminary concept selection. The process is then repeated, starting with the development of a functional specification, which is followed by formalized concept generation and selection methods, layout and detailed part design using solid modelers, experimental and analytical methods for answering design questions, simultaneous part and manufacturing process design, prototype, and production sample. This design process includes a high degree of concurrent involvement from each of the disciplines on the project team.</jats:p> <jats:p>Non-traditional teaching methods that have proven useful in the class include the use of an industrial paradigm for the educational experience, the use of faculty coaches to mentor the student teams, the use of projects sponsored by industry with regular feedback from the industrial customer, just-in-time education so that students can see immediate application of what is taught, the use of skits and role-playing to teach interpersonal skills, and specific activities that help in the production of project deliverables.</jats:p> <jats:p>The use of this design process and these teaching methods has led to successful design education. Students, faculty, and industrial customers have all been pleased with the success of the Capstone program in producing superior design engineers.</jats:p>
IEEE Access, 2020
An origami-based foldable and reconfigurable Reflectarray Antenna (RA) with multiple apertures is... more An origami-based foldable and reconfigurable Reflectarray Antenna (RA) with multiple apertures is proposed for CubeSat applications. The proposed configuration consists of a central RA embedded in folding panels using Lamina Emergent Torsional (LET) joints based on compliant mechanisms. Depending on the folding direction of these panels (forward or backward), a new RA aperture is formed. The proposed RA along with its folding panels and hinges is fabricated using only a single PCB. A prototype of such an RA with two foldable panels is fabricated and measured. This RA operates in the Ku-band at 16 GHz and provides two pencil beams pointing at (θ = 30 • , ϕ = 0 •) and (θ = −30 • , ϕ = 0 •), and a dual-beam pointing at (θ = +27 • , ϕ = 0 •) and (θ = −29 • , ϕ = 0 •). The proposed RA provides a gain of 25 dB and 19 dB in its single-and dual-beam operations, respectively. For CubeSat applications, the key advantages of this RA are its small stowed volume, reconfigurable EM performance, beamsteering capabilities, monolithic construction, low fabrication cost, and reduced complexity.
2021 IEEE 21st Annual Wireless and Microwave Technology Conference (WAMICON), 2021
In this work, an ultra-wideband microwave absorber based on a Tachi-Miura Polyhedron (TMP) origam... more In this work, an ultra-wideband microwave absorber based on a Tachi-Miura Polyhedron (TMP) origami structure is presented. By appropriately folding the TMP at a specific angle, the proposed absorber acts as a honeycomb design, thereby offering superior absorption performance compared to the stateof-the-art absorbers. Specifically, it exhibits an absorptivity of more than 90% in the wide frequency band of 1.22 GHz to 30 GHz for both transverse electric (TE), and transverse magnetic (TM) waves. A fractional bandwidth of 1.84 is supported that proved the ultra-wideband absorption.
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Papers by Spencer Magleby