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In helmet impact testing, parameters including acceleration and velocity are measured using instrumented head-neck models that are meant to be mechanically realistic (i.e. biofidelic) stand-ins, or surrogates, for humans. Currently available models of the human neck are designed primarily for application in automotive crash testing, and their applicability in assessment of helmets is often questioned. The object of the present work is to document the mechanical design, repeatability, and biofidelity in low speed impact of a new neck model that we apply with a Hybrid III head. Focusing on Hybrid III head kinematics measured during impacts at 2 to 6 m/s, the co-efficient of variance of repeated measures of kinematics was generally less than 10%. Differences in kinematics between identical copies of the neck was less than 20% when tested with helmets, and less than 7% when the head was not helmeted. In parallel testing using a Hybrid III head-neck, the co-efficient of variance in repeated measures was less than 4% and the kinematics significantly differed from those measured using the new neck. CORAplus scores for the new neck were approximately 0.70 when compared against data for human subjects with passive neck muscles experiencing impact at 2 m/s.

The objective of this paper is to develop and experimentally validate an open-source software package in MATLAB/Simulink, named OrbSim, which can numerically simulate the trajectory and attitude of a satellite such as a CubeSat in very low Earth orbit (VLEO). The modeled disturbances acting on the satellite include aerodynamic, gravitational, solar radiation pressure, and magnetic forces and torques. OrbSim was first validated against AGI’s Systems Tool Kit (STK), an industry standard software package for simulating satellite orbital dynamics, by simulating orbital trajectories using different permutations of the disturbances being modeled by each package. OrbSim was found to perform on par with STK. A second validation involved predicting the orbital lifetime of an actual satellite, the Humanity Star, with OrbSim’s prediction being accurate to half a day of the true reentry time.

The main aim of this randomized clinical trial was to determine 3 dimensional skeletal and dental changes six months after the use of bone-anchored versus tooth-anchored rapid maxillary expanders in adolescents. The secondary aim was to determine the symmetrical or asymmetrical expansion pattern between both appliances.Fifty adolescents with skeletally constricted maxilla (mean age 13-14 years) were randomly assigned into: Dresden B-RME, Hyrax T-RME, or untreated control groups. CBCT scans were taken at initial and expander removal (6 months). Three-dimensional references and treatment landmarks were identified. Orthogonal distances were calculated from those landmarks. The main outcome was to compare skeletal and dental changes in each group and the secondary outcome was to verify if these changes were symmetric or not. Data was analysed using descriptive statistics and repeated measure MANCOVA and MANOVA.Both treatment groups showed significant skeletal and dental expansion compared to controls. T-RME group had greater mean inter-molar crown expansion (5.66mm) than the B-RME group (4.17mm). Both T-RME and B-RME groups showed significant skeletal maxillary expansion compared to controls (mean 1.27mm and 1.31mm respectively, both p0.01), although no significant difference was found between both appliances. B-RME group showed a lower ratio of dental to skeletal expansion than T-RME group. T-RME showed a symmetrical expansion pattern, whereas the B-RME showed an asymmetrical pattern relative to mid-sagittal plane. The extent of molar crown expansion was 1.84mm greater on the TAD-side compared to the Implant-side. T-RME group showed significant anterior movement of the maxillary first premolar and molar (1.5mm, p0.05), and vertical dental extrusion (1.8mm). No significant dental vertical or anterior-posterior changes were noted in the B-RME group.T-RME and B-RME produced similar amounts of skeletal expansion. B-RME group produced a lower component of dental expansion. Due to the Dresden B-RME configuration, asymmetrical expansion was noted.

Purpose The presented study utilized an in vitro Orthodontic SIMulator (OSIM) to study how Class II elastic configuration effects the forces and moments acting on maxillary canine teeth when using a straight archwire fixed lingual appliance. Materials and methods Maxillary in-Ovation L self-ligating brackets were bonded to anatomically shaped stainless steel teeth on OSIM. A 0.016″ × 0.022″ stainless steel straight lingual archwire was used to provide a relevant arch shape and to position simulated teeth in a passive position. A mandibular typodont was positioned above the OSIM arch in a half cusp Class II malocclusion to serve as attachment points for elastics. Four different elastic configurations were tested: 1. maxillary–buccal to mandibular-buccal; 2. maxillary–lingual to mandibular–lingual; 3. maxillary–buccal to mandibular–lingual; 4. maxillary–lingual to mandibular–buccal. A new 4.5 oz 3/16″ elastic (n = 40 per configuration) was attached to the maxillary canine and mandibular first molar teeth for each trial. Forces and moments at the maxillary canine simulated center of resistance were considered. ANOVA was used to assess the effect of elastic configuration, and pairwise comparisons using Bonferroni correction were conducted to investigate configuration differences. Results Of the thirty-four pairwise comparisons, only two were statistically insignificant. Configurations 1, 2, and 4 were found to produce over 1 N of force in the desired distal direction, whereas Configuration 3 was significantly lower at 0.65 N. Conclusions Overall, the configuration of Class II elastics had a significant effect on forces and moments at maxillary canine teeth for a simulated straight archwire fixed lingual appliance.

The goal of this investigation was to adapt and incorporate a nonlinear viscoelastic material model representative of the midpalatal suture’s viscoelastic nature into finite element analysis simulations of maxillary expansion treatment. Step-wise displacements were applied to a partial skull geometry to simulate treatment using an expansion screw appliance. Four simulation cases were considered for the midpalatal and intermaxillary sutures: 1. Neglecting suture tissue; 2. Linear elastic properties; 3. Viscoelastic properties; 4. A fused intermaxillary and viscoelastic midpalatal suture. Results from simulations indicated that removal of suture tissue and inclusion of viscoelastic properties resulted in the same maxillary displacement following 29 activations of 0.125 mm applied directly to the maxilla; however, assuming a fused intermaxillary suture significantly changed maxillary displacement patterns. Initial stress results within the suture complex were significantly influenced by the inclusion of suture viscoelasticity as compared to linear elastic properties. The presented study demonstrates successful incorporation of suture viscoelasticity into finite element analysis simulations of maxillary expansion treatment, and elucidates the appropriateness of various suture material property assumptions depending desired research outcomes.

There is an increasing demand for the use of “green”-based materials as reinforcement and matrix materials in composites. However, the ability of these natural-based materials to perform as consistently and reliably as conventional materials is still relatively unknown. A key importance in the viability of these materials is the evaluation of the content of voids and imperfections, which may affect the properties of the entire composite. In this study, the microstructure of tubular-braided composites manufactured from cellulose fibers and a partially bio-derived resin was studied with the use of micro-computed tomography. These methods were used to determine the effect of modifying braid angle, resin type, and curing method on fiber volume fraction, void volume, and void distribution. It was determined that the void content increased with the increase in braid angle, and vacuum-bagging reduced the total void content. The sample with the smallest braid angle produced with vacuum-bagged curing contained a void fraction of 1.5%. The results of this study proved that the materials used could be viable for further testing and development and that micro-computed tomography imaging is valuable for identifying how to improve consistency and minimize imperfections to create more accurate and reliable natural fiber-braided composites.

Assessment is an essential step in the teaching and learning process. Traditional examination methods (closed-book, time-constrained, invigilated, multiplechoice) prevail in higher education despite support foralternative approaches wherein students construct knowledge through active, authentic activities. A review ofthe scholarly literature focused on merits and limitations of traditional closed-book exams in-person and in anonline, remote course delivery context, as well as benefits, concerns, and considerations of transitioning to open-book exams at a time of upsurge in online learning. Within the dichotomy of traditional versus alterative exam strategies, the literature is inconclusive on shared matters, including student academic integrity, study habits, anxiety, performance, and long-term retention of information.

Evidence-based teaching strategies (EBTs) are connected to positive outcomes for students. Engineering instructors are tasked with using EBTs to scaffold student mastery of graduate attributes, now amidstan upsurge in online, remote course delivery. The Graduate Attribute Tipsheet Series developed by theFaculty of Engineering at the University of Alberta provides instructors with current, relevant, and tangibleinformation in a succinct format that is mindful of their high workloads and time constraints. The tipsheet less-is more development process was careful and iterative to ensure only the most important, useful points from high quality, credible sources were included. Lessons learned from this initiative can be applied to future resources that support instructors in their use of EBTs in an online learning context and are responsive to the inevitable flux of teaching circumstances in engineering education.

Teaching online in higher education is a complex integration of educational technologies, good pedagogical practices, and content knowledge. Concerns and resistance by instructors may be fueled by lack ofunderstanding and resources, to which faculty administration can respond with targeted, ongoing communication and education. A faculty intranet initiative within the Faculty of Engineering at the University of Alberta was created to support instructors amidst their efforts to prepare and deliver online, remote versions of their courses for the Fall 2020 term. The intranet infrastructure was well-suited for the relevant, timely, and tailored digital resources specific to engineering content and circumstances. Beyond the COVID-19 pandemic, it is intended for the intranet to grow into a collaborative virtual space where users can share their knowledge, experience, and insights to build a community of practice.

After 2009, accredited Canadian engineering schools began to develop processes to map the Canadian Engineering Accreditation Board-Graduate Attributes(CEAB-GAs) to their curriculum and integrate ways to measure them. At around the same time, several Canadian universities embarked on a process to identifytheir own University-wide Graduate Attribute (UGAs). UGAs are assumed to be applicable across study disciplines; i.e. the university experience as a whole.To address the need to assess students on the basis of the CEAB GAs and the UGAs in the Faculty of Engineering and develop the basis for an integrated graduate attribute management system, an interdisciplinary team conducted a yearlong qualitative study with the purpose of exploringthe intersection of the UGAs with CEAB-GAs. The key objectives were to develop a mapping process between the two sets and to explore management strategies for assessing both sets of graduate attributes. Two independent teams performed the mapping exercise using a sequential mixed methods study design. A qualitative exploratory mapping study was followed by a quantitative aggregation of the mapping results. Integration of the qualitative and quantitative study results was completed as part of the interpretation of the results. Both forward and backward mapping took place. Results demonstrated that, although generic, UGAs may not necessarily capture specific professional program graduate attributes such as the CEAB-GAs. The study also highlighted the need for more revisions and updates of UGAs by including various stakeholders who can substantially contribute to implementation and assessment of UGAs.

In helmet impact testing, parameters including acceleration and velocity are measured using instrumented head-neck models that are meant to be mechanically realistic (i.e. biofidelic) stand-ins, or surrogates, for humans. Currently available models of the human neck are designed primarily for application in automotive crash testing, and their applicability in assessment of helmets is often questioned. The object of the present work is to document the mechanical design, repeatability, and biofidelity in low speed impact of a new neck model that we apply with a Hybrid III head. Focusing on Hybrid III head kinematics measured during impacts at 2 to 6 m/s, the co-efficient of variance of repeated measures of kinematics was generally less than 10%. Differences in kinematics between identical copies of the neck was less than 20% when tested with helmets, and less than 7% when the head was not helmeted. In parallel testing using a Hybrid III head-neck, the co-efficient of variance in repeated measures was less than 4% and the kinematics significantly differed from those measured using the new neck. CORAplus scores for the new neck were approximately 0.70 when compared against data for human subjects with passive neck muscles experiencing impact at 2 m/s.

The Experimental Albertan satellite #1 (Ex-Alta 1) was a three-unit cube satellite (CubeSat) developed at the University of Alberta (UAlberta). As the first ‘made in Alberta’ spacecraft, the Ex-Alta 1 CubeSat was the Canadian contribution to the international QB50 CubeSat constellation mission ( www.qb50.eu ). Ex-Alta 1’s mission incorporated four science objectives, two technical objectives, and one educational outreach objective. These are reviewed in the context of the Ex-Alta 1 mission design, as well as future CubeSat constellation missions that may follow demonstration missions such as Ex-Alta 1 and the experiences of the QB50 project. In support of its objectives, Ex-Alta 1 flew the multi-needle Langmuir probe (m-NLP) QB50 standardized payload, a UAlberta developed miniaturized digital fluxgate magnetometer (DFGM) mounted on a two-element articulated deployable boom, a radiation dosimeter from Teledyne, and an open source onboard computer (OBC) developed at UAlberta. Ex-Alta 1 was released by a NanoRacks deployer from the International Space Station on May 26, 2017, and commanded and controlled from a ground-station developed and operated at UAlberta. Ex-Alta 1 operated continuously throughout its mission until it burned up in the atmosphere on November 14, 2018. The last two-way contact occurred on that day at 07:49:29 UTC, when the spacecraft reported an onboard temperature of 47 °C in eclipse at an altitude of 152 km and which marked the effective end of the mission. This paper provides an overview of the Ex-Alta 1 mission, its development, the spacecraft and mission design, and reports preliminary results from the payload focusing on the DFGM instrument. We also report briefly on related education and outreach activities, including the development and delivery of curriculum-targeted and CubeSat focused classroom sessions inspired by the Ex-Alta 1 mission to school pupils in Alberta.

Objective To compare the biomechanics of straight labial, straight lingual, and mushroom lingual archwire systems when used in posterior arch expansion. Materials and Methods An electro-mechanical orthodontic simulator allowing for buccal–lingual and vertical displacements of individual teeth and three-dimensional force/moment measurements was instrumented with anatomically shaped teeth for the maxillary arch. In-Ovation L brackets were bonded to lingual surfaces, and Carriere SLX brackets were bonded to labial surfaces to ensure consistency of slot dimensions. Titanium molybdenum archwires were bent to an ideal arch form, and the teeth on the orthodontic simulator were set to a passive position. Posterior teeth from the canine to second molar were moved lingually to replicate a constricted arch. From the constricted position, the posterior teeth were simultaneously moved until the expansive force decreased below 0.2 N. Initial force/moment systems and the amount of predicted expansion were compared for posterior teeth at a significance level of α = 0.05. Results Archwire type affected both the expected expansion and initial force/moment systems produced in the constricted position. In general, the lingual systems produced the most expansion. The archwire systems were not able to return the teeth to their ideal position, with the closest system reaching 41% of the intended expansion. Conclusions In general, lingual systems were able to produce greater expansion in the posterior regions when compared with labial systems. However, less than half of the intended arch expansion was achieved with all systems tested.

Safety is one of many imperatives considered by engineers as they design, build, test, and maintain solutions to meet client needs. The mindset and relevant knowledge of individual engineers toward safety is formed n the tertiary classroom, which students then carry with them into their careers and influence the safety culture of heir workspaces. As an innovative means to include safety content in the University of Alberta’s Faculty of Engineering undergraduate programs, a large-scale project tasked co-op students with creating videos promoting and instructing on safety concepts and procedures in laboratory spaces. Beyond the deliverables, this authentic, active learning experience increased the safety knowledge and commitment of both students and staff, infiltrating and positively impacting the safety culture within all engineering and science programs.

Faculty resistance toward outcomes-based education (OBE) can be sorted into two categories— lack of understanding and lack of resources—and can be addressed by leadership through increased education and communication. With this in mind, the Faculty of Engineering at the University of Alberta has created an online OBE Resource Hub on its faculty intranet, guided by the question, “What kinds of education and communication do faculty require to gain knowledge and acceptance of OBE, and therefore be engaged and motivated in the process?” Artifacts on the ever-growing site include theoretical and practical information in the form of articles, tipsheets, videos, and external links. This article showcases the site, since an initiative of this nature might be of interest to other post-secondary faculties working toward OBE.

Two-dimensional braided composite materials consist of an impregnated and cured braided fiber structure. The braid angle, which describes the orientation of fibers on the mandrel, affects the mater...

Rapidly determining root growth patterns is biologically important and technically challenging. Current methods focus on direct observation of roots and require destructive excavations or time-consuming root tracing. We developed a novel methodology based on analyzing soil particle displacement, rather than direct observation of roots. This inferred root growth method uses digital image correlation (DIC) analysis, an established and high-throughput method used in many engineering and science disciplines. By applying DIC analyses to repeated images of plants grown in clear window boxes, we produced visually intuitive and quantifiable strain maps, indicating the magnitude and direction of soil movement. From this, we could infer root growth and rapidly quantify root system metrics. Strain measures were closely associated with the spatial distribution of roots and correlated with root length measured using conventional approaches. The method also allowed for the detection of root proliferation in nutrient-enriched soil patches, indicating its suitability for quantifying biological patterns. This novel application of DIC in root biology is effective, scalable, low cost, flexible and complementary to existing technologies. This method offers a new tool for answering questions in plant biology and will be particularly useful in studies involving temporal dynamics of root processes.

Objective: The purpose of this systematic review was to synthesize the available literature concerning the reliability of three-dimensional superimposition methods when assessing changes in craniofacial hard tissues. Materials and Methods: Four electronic databases were searched. Two authors independently reviewed potentially relevant articles for eligibility. Clinical trials, cohort, case-control, and cross-sectional studies that evaluated the reliability of three-dimensional superimposition methods on the anterior cranial base were included. Results: Six studies fulfilled the inclusion criteria. Four studies used the voxel-based registration method, one used the landmark-based method and one used the surface-based method. Regarding reliability, the voxel-based studies showed on average a difference of 0.5 mm or less between images. The optimized analysis using a six-point correction algorithm in the landmark-based method showed 1.24 mm magnitude of error between images. Conclusions: Although reliability appears to be adequate, the small sample size and high risk of bias among studies make available evidence still insufficient to draw strong conclusions.

Material extrusion additive manufacturing (MEAM), a sub-branch of three-dimensional (3D) printing is growing in popularity. Test specimens were 3D-printed using commercial polylactic acid (PLA) filament, and PLA filament reinforced with short-carbon fibers (PLA/CF). As-printed specimens and specimens that were annealed at three different temperatures, then subjected to tensile testing. The internal microstructures of the samples were also examined. The effects of the short-carbon fiber fillers on the mechanical properties of 3D-printed PLA were investigated, and the effects of the annealing process on polymer crystallinity and mechanical properties. The annealing process was shown to increase the crystallinity of both sample groups, though no statistically significant effect of annealing on mechanical properties was observed. The tensile properties of the PLA and PLA/CF filaments showed that the addition of carbon fibers to the PLA filament led to a significant increase in elastic modulus of the MEAM samples.

Introduction An Orthodontic SIMulator (OSIM) was used to investigate the propagation of forces and moments around a simulated archform for a gingival displaced canine and lingual displaced lateral incisor using fixed lingual orthodontic appliances. Methods In-Ovation L self-ligating lingual brackets were bonded to anatomically shaped teeth on the OSIM, and the teeth were positioned such that a G4 NiTi 0.016" large maxillary mushroom archwire could be ligated in passive position. Each trial consisted of two movements: a 3mm lingual displacement of the 1-2 lateral incisor at 0.2 mm increments, and a 1.5 mm gingival displacement of the 2-3 canine at 0.15 mm increments (n = 50). Anterior brackets were repositioned to accommodate G4 NiTi 0.016" universal straight archwires (n = 50). Tests were completed at 37°C, and force and moment data in all directions was collected for each tooth around the arch at all increments. Results In general, the straight archwire produced significantly larger forces and moments at the centre of resistance for teeth of interest than did mushroom archwires. Specifically, the straight archwire produced 2.62 N and 3.81 N more force in the direction of tooth movement on the tooth being moved for a gingival displaced canine and lingual displaced lateral incisor, respectively, as compared to mushroom archwires. Conclusions Results from this study suggest that mushroom archwires may provide better mechanics for movement of teeth in the anterior segment when using a round archwire; however, only biomechanical data was considered in this study and there are many factors that need to be considered in treatment planning.

The CEAB accreditation requirement of graduate attributes and continual improvement processes (GACIP) has been a pervasive topic in the annual CEEA conference proceedings since 2010. The proceedings are a rich primary source of work being done in Canadian tertiary institutions. This narrative review of the literature consolidates and discusses the relevant CEEA papers for 2010-2017 in a manner that is useful to leadership and decision-makers at accredited faculties of Engineering nationwide. Four guiding research questions were asked of this literature: (1) What general frameworks are being implemented as accredited faculties of Engineering across Canada approach GACIP?; (2) What are the specific activities and methods of one or more of the GACIP steps?; (3) What are the roles and responsibilities of people involved?; and (4) What perspectives are taken in response to the CEAB accreditation criteria, including concerns, issues, and benefits? A qualitative content analysis was conducted on 106 papers meeting selection criteria. Emergent topics were used to form the discussion.

Upper limb loss is a devastating injury for which current prosthetic replacement inadequately compensates. A lack of wrist movement in prostheses due to mechanical design and control system considerations compels prosthetic users to employ compensatory movements using their upper back and shoulder that can eventually result in strain and overuse injuries. One possible means of easing this control burden is to allow a prosthetic wrist to self-regulate, keeping the terminal device of the prosthesis level relative to the ground when appropriate, such as when raising a cup of liquid. This study aims to outline such a wrist control scheme, and evaluate its function in terms of the effect on compensatory movements, objective system performance, and subjective perception of system performance based on user feedback. To that end, twelve able-bodied participants were recruited to control a body-mounted robotic arm using three different control schemes: fixed-wrist (FW), sequential switching (SS), and automatic levelling (AL). The resulting movement strategies were recorded for two different tasks using 3D motion-capture. SS and AL control schemes induced similar movement strategies and less compensation than FW for horizontal movements, while AL reduced shoulder flexion compared to FW and SS for vertical movements. However, AL was ranked less intuitive and less reliable than the FW. AL and SS both seemed to involve more conscious thought to operate than FW. These results suggest that more complex wrist control schemes may indeed be able to eliminate harmful compensatory movements, but reinforce prior observations that control must be reliable and simple to use or people will opt for an easier system.

Braided composites can be manufactured in a variety of braid patterns: Diamond (1/1), Regular (2/2), and Hercules (3/3) and with longitudinal reinforcement (Triaxial). The complex strain fields, which could help reveal phenomenological behavior of braids, have not been experimentally assessed. As such, the objectives of this article were to investigate the effect of braid pattern (Diamond, Regular), braid angle (35°, 45°, 55°), and load (tensile, torsion) on the strain field and elastic properties (longitudinal and shear moduli) using a three-dimensional digital image correlation method. The methodology presented in this manuscript will be used to validate a new analytical model, which predicts the elastic properties of tubular braided of both varying braid type and braid angle.

Tubular braided composites are manufactured using a Maypole braiding machine which interlaces yarns in order to manufacture a braided structure. Braids can be produced in Diamond (1/1), Regular (2/2) and Hercules (3/3) patterns. In addition, axial yarns can be included in order to produce triaxial braid structures. Several analytical and finite element analysis models have been developed in order to predict the elastic properties of braided composites. Despite the fact that many models exist for braided composites, a comprehensive model has not been presented that can capture the variety of braiding patterns which can be manufactured using the braiding process. In this study, a new analytical model has been developed that can describe the elastic properties of Diamond, Regular and Hercules braids. The proposed analytical model uses a volume averaging stiffness method in order to account for yarn undulations and the orientation of braid yarns within the braid structure. The model presented here has been compared with the existing FEA and analytical models and has also been validated experimentally. Experimental validation comprised tensile and torsional tests in order to predict the longitudinal and shear moduli for both Diamond and Regular braid geometries. The experimental and proposed model results highlight the effect of braiding pattern and braiding angle on the mechanical properties.

Three dimensional (3D) printing is a technique conventionally used to manufacture prototypes. Commercial desktop 3D printers have become available which produce functional 3D printed parts. The MarkOne by Mark Forged manufactures printed structures reinforced with continuous Carbon, Fiberglass or Kevlar fibers. The aim of this study is to evaluate the elastic properties of the fiber reinforced 3D printed structures and predict elastic properties using an Average Stiffness (VAS) method. Samples evaluated in this study were produced by varying the volume fraction of fibers within the 3D printed structures (4.04, 8.08 and 10.1% respectively). The experimentally determined elastic modulus was found to be 1767.2, 6920.0 and 9001.2 MPa for fiber volume fractions of 4.04, 8.08 and 10.1% respectively. The predicted elastic moduli were found to be 4155.7, 7380.0 and 8992.1 MPa. The model results differed from experiments by 57.5, 6.2 and 0.1% for the 4.04, 8.08 and 10.1% fiber volume fractions. The predictive model allows for the elastic properties of fiber reinforced 3D printed parts. The model presented will allow for designers to predict the elastic properties of fiber reinforced 3D printed parts to be used for functional components which require specific mechanical properties.

Force Sensitive Resistors (FSRs) are commercially available thin film polymer sensors commonly employed in a multitude of biomechanical measurement environments. Reasons for such wide spread usage lie in the versatility, small profile, and low cost of these sensors. Yet FSRs have limitations. It is commonly accepted that temperature, curvature and biological tissue compliance may impact sensor conductance and resulting force readings. The effect of these variables and degree to which they interact has yet to be comprehensively investigated and quantified. This work systematically assesses varying levels of temperature, sensor curvature and surface compliance using a full factorial design-of-experiments approach. Three models of Interlink FSRs were evaluated. Calibration equations under 12 unique combinations of temperature, curvature and compliance were determined for each sensor. Root mean squared error, mean absolute error, and maximum error were quantified as measures of the impact these thermo/mechanical factors have on sensor performance. It was found that all three variables have the potential to affect FSR calibration curves. The FSR model and corresponding sensor geometry are sensitive to these three mechanical factors at varying levels. Experimental results suggest that reducing sensor error requires calibration of each sensor in an environment as close to its intended use as possible and if multiple FSRs are used in a system, they must be calibrated independently.

Orthodontic archwire rotation around its long axis, known as third-order torque, is utilised to correct tooth rotational misalignments moving the tooth root closer to or away from the cheek through engagement with an orthodontic bracket. Studying the behaviour of archwire and brackets during an applied rotation can aid in better understanding and appreciating the mechanics of third-order torque, potentially allowing for more effective orthodontic treatment protocols. Mechanically characterising archwire behaviour during third-order torque application is a complex task due to their physical scale and geometries. An advanced measurement technique was needed to address these constraints. A three-dimensional (3D) non-contact optical method using a digital image correlation (DIC) system was developed. An orthodontic torque simulator (OTS) was used to apply and measure third-order torque with 0.483 × 0.635 mm (0.019″ x 0.025″) rectangular archwires in tandem with a 3D DIC system, whereby surface deformations and strains could be computed using correlation algorithms. The 3D DIC system was implemented to enable third-order torque experimentation with the OTS while imaging the archwire and bracket surfaces. The 3D DIC system's ability to measure 3D archwire deformations and strains was verified using a finite element model, where comparisons between 3D DIC measurements and calculated results from the model were made to ensure the measurement capabilities of 3D DIC in the context of third-order torque. The 3D DIC system was then used to compare archwire behaviour between stainless steel (SS) and titanium molybdenum alloy (TMA) archwires to study potential clinical differences in archwire behaviour, in which the archwires were rotated with a custom SS rigid dowel (RD) as well as commercial Damon Q orthodontic brackets. The quantification of third-order torque and archwire deformations and strains led to the conclusion that SS archwires led to larger torque magnitudes compared to TMA archwires. The RD resulted in larger archwire strains compared to Damon Q brackets. The 3D DIC system provides a non-contact measurement technique that can further be used with third-order torque experimentation with the OTS.

Increasing concerns regarding human-driven effects on the biosphere have led to the development and adoption of environmentally friendly “green” composites. Unlike conventional synthetic composites, green composites are made of natural materials in either the matrix or the fiber reinforcement (or both). They are claimed to have lower negative environmental effects due to their sustainability and easier recyclability. To assess the environmental impacts associated with any product, a life cycle assessment (LCA) is needed. This literature review summarizes the individual steps undertaken in an LCA study and discusses their relevance within the field of green composites. Similarly, an outline of life cycle costing (LCC), a type of study which determines the economic implications of a product, is incorporated. Since some phases of a product’s life cycle can have significant environmental effects, parameters affecting the time-dependant degradation of green composites and their significance in LCA studies were also explored. Finally, criteria for choosing natural fibers and biopolymers for green composites in engineering applications were considered, and case studies of hemp and flax as candidates for fiber cultivation in Alberta, Canada are provided throughout.

Muscle is typically modelled using a lump sum idealization, scaling a single fascicle to represent the entire muscle. However, fascicles within a muscle have unique orientations, which could result in forces exerted not only in the axis running along the tendon, but also the two perpendicular axes, describing the muscle's width and depth. The purpose of this research was to develop a geometric-based model of the soleus, medial gastrocnemius, and lateral gastrocnemius as distributed force systems which can predict three-dimensional forces. Measurements were taken from the triceps surae in two human cadavers (80 and 85 years old). These models predicted muscle volumes and ankle plantar flexor moments that were realistic considering the age of the cadavers. Small differences were observed in calcaneal tendon force and moment for the distributed force models compared to modelling muscle force using a lump sum idealization. The major finding of the distributed force models was that forces were present in the axes corresponding to the muscle's length, width, and depth. The forces in the width and depth axes may be relevant for evaluating how muscle shape changes during contraction, as well as to investigate stress-strain patterns along the muscle's proximal and distal aponeuroses.

Performance using myoelectric prostheses, especially considering recent developments in pattern recognition-based control, is significantly impacted by user training with the selected control strategy. However, minimal research has been done into the effect of functional user training with different myoelectric control strategies, since doing so typically requires training and evaluating prosthesis users with differing device configurations and customized socket fittings. Intermediate platforms such as desktop-mounted robotic arms present an opportunity for consistent training of participants both able-bodied and with amputations. In this paper, a training environment and protocol for improving myoelectric prosthetic control with a desktop-mounted robotic arm was developed and assessed with pattern recognition as the control method. Pre-training and post-training performance for 10 able-bodied participants was evaluated using the Target Achievement Control test for 1, 2 and 3 degrees of freedom. Results showed significant differences in performance before and after 1 hour of desktop training. These results support the hypothesis that a desktop training protocol may improve performance with pattern recognition-based control.

Abstract - Contemporary engineering product design and development no longer adheres to the boundaries of a single discipline and has become tightly integrated, often relying on interaction of multiple disciplines for completion of integrated product design projects. In order to design these products, design and development practice has transcended the discipline boundaries to become a transdisciplinary engineering design process. A collaboration of specialists from different engineering disciplines is required to develop efficient solutions to interdisciplinary problems of product design. Despite this shift from mono-disciplinary to transdisciplinary, the engineering design curriculum remains focused on teaching discipline specific design practice through skill based subject specific pedagogy with a limited emphasis on the importance of design process and transdisciplinarity in the design process. As a result, new graduates starting in design and development organizations face a difficulty finding a common basis of understanding of disciplines’ interactions and must go through a process of often implicit ‘onboarding’ to understand the transdisciplinary engineering design process. This can be avoided by developing and adapting undergraduate design process education in line with industrial demands. This paper proposes a theoretical framework based on empirical engineering design research in industry, educational psychology and teaching approaches such as Bloom’s Taxonomy and Kolb’s Model of Experiential Learning for developing the core elements of a transdisciplinary engineering design process curriculum.