Over the course of this year nest specimens from four of the ve Colletidae subfamilies and annalyzed their properties. It was demonstrated by previous work at this institution that the nest cells of at least one specie of Colletidae were not in fact just layers of polyester, but a composite of polyester and silk. The aforementioned work culminated in a Masters thesis at the University of Bath by Rebecca Belisle (Belisle 2011.) The focus of this research was to compare nest cell characteristics with what we know about the nesting behavior of the bees across all subfamilies, the documentation of which is extensive. It was found that the nesting behavior of each subfamily heavily correlated to the cell characteristics observed under our testing.

For my research, I set out to create a vision system to enable an aqueous vehicle to autonomously navigate harbors. The application in mind for this system is for robotic (unmanned) research vessels for oceanic research missions. The vessel will contain appropriate sensors to whatever observations need to be made, whether it is testing chemical contents of the water, biomass moving through an area, or tracking various groups of animals. Eventually, my research scope expanded to working some on the architecture level to find ways to integrate two distinct architectures for seamless flow between low-level, small time-scale thinking with long-term analysis and planning.

Green building standards like the Living Building Challenge promote the construction of net-zero energy buildings. In order to meet these standards, alternative heating and cooling methods become necessary, especially for designs with high glazing percentages in temperate climates, such as for aesthetic purposes or use in greenhouses. The design and analysis of a low-cost heating and cooling system is being investigated to address these scenarios. Air-source heat pumps are now commonly used in super-insulated, net-zero energy building designs, and we explore the possibility of augmenting this configuration with an inexpensive seasonal thermal energy store to address the increased heating and cooling loads. A high-glazing building scenario was modeled in Revit to establish monthly loads for a proposed building design, and a heat transfer model of a thermal store coupled to a heat pump was simulated in COMSOL Multiphysics to test feasibility of this idea. The results suggest this strategy has potential but may be limited in application due to its large size.

Polyhydroxyalkanoates (PHAs) are a class of biodegradable polymers which can be produced via bacterial synthesis. They have garnered interest due to their potential as a biodegradable alternative to petroleum-based plastics. PHA molecules have been shown to have a helical morphology, which organize into spherulitic crystal structures. The most common, naturally occurring PHA, poly(3-hydroxybutyrate) (PHB), typically has a crystallinity of up to 75-85% in its homopolymer form. The resulting material is thus brittle and has a narrow processing window. However, a broad range of mechanical properties has been achieved with the inclusion of varying quantities of 3-hydroxyhexanoate (HHx) units to form the polymer P(HB-co-HHx).

The nature of this research is to prototype different types of perching landing gears for drones. Using natural mechanisms found in animals, our team created two bio-inspired designs of perching landing gears for unmanned aerial vehicles (UAV’s). These designs were able to demonstrate the feasibility of landing-gear systems that enable bird-sized UAV’s to perch and take-off from branch-like structures.

We have derived compact algebraic bounds for the limit behavior of the magnetic coupling coefficient, κ, for axially aligned multilayer coils. These bounds are validated experimentally. We have also found an expression based on the coil geometry that captures its long-range magnetic behavior. In particular, the limit behavior of the magnetic coupling coefficient is the same for any pair of axially aligned multilayer coils when the separation distance is normalized by this expression.

An engineer is defined as “a person who has scientific training and who designs and builds complicated products, machines, systems, or structures.1” This paper will explore a new definition of engineer—engineer as anthropologist and critical thinker.

Current robotic sailing relies on sensing wind direction and moving the sails to a position that is appropriate for that relative wind angle. The research to date shows that a correctly tuned sail in the classic wing shape is essential for maximum speed over water. This paper relates research on sensors used to determine when sail trim is incorrect. With improper sail trim, the sail luffs. This luffing produces turbulence which reduces the efficiency of the sail. By instrumenting the sail with sensors to detect when sails begin to luff, the robot can determine when the sail is improperly trimmed and, potentially, take corrective action.

Currently, when a blind person goes grocery shopping, the store management must provide an employee to guide the blind customer and heavily assist with most, if not all, of the shopping. This `dependent shopping' situation often makes the blind person uncomfortable since it calls attention to the handicap and strips him/her of self-sufficiency. The project's motivation is to improve the shopping experience of the blind such that the user can shop independently and efficiently simply by installing new software onto the electronics that they already use daily. This will be done with a combination of crowdsourcing (in which a human will identify the desired grocery item, i.e. object recognition) and computer vision (in which the device will track the item from image to image and navigate the user to the product).

Poly(methyl methacrylate), known commonly as acrylic, is a transparent thermoplastic polymer. Acrylic is a choice material for laser cutting due to the ease with which it is machined. Some desirable qualities of PMMA include high light transmission and the aesthetic appeal of transparency. PMMA is widely used for illuminated as well as non-illuminated display signs. Trophies and memorabilia often use cast acrylic as the base material due to the high visual contrast produced by engraving the material. Furthermore, acrylic is often used as a shatterproof glass substitute. It is more weather resistant than other plastics as polystyrene and polyethylene and therefore often found in outdoor applications.

The robotic revolution dramatically increased the number of tasks which robots perform. It continues to do so, especially within the maritime industry, where robotic applications are being developed across a wide variety of platforms from power to sail. One challenge faced when constructing sailing robots is the inability to determine the state of the sail if there is no human at the helm watching and reacting to constantly changing wind conditions. Traditional, flexible sails begin to “luff” or flap in the wind if are not set correctly. With this comes a decrease in sail efficiency and hull speed because the sails no longer generate maximum lift. In the worse case, the boat reaches a state of being in “irons” where it stalls in the water, bow to the wind. In previous research I showed sensors could be placed on the sail to detect this luffing. In this research, I present a quantitative comparison of three different methods of sensing sail luffing: piezoelectric vibration, air pressure, and acceleration. The relative effectiveness of these methods is compared against position data obtained using computer vision during sets of binary tests where the sail can be considered to luff or to hold its shape. Results are promising and show that each sensor is able to detect sail luffing. However, there are also clear use cases where one sensor is preferable.

Engineering for Humanity, an interdisciplinary engineering design and anthropology course at Olin College of Engineering, is a semester-long service-learning partnership between the college and nearby Councils on Aging. This paper examines the effects of this service learning on our students and their partners. Our research suggests that this service-learning curriculum has positively impacted students’ and elder partners’ behavior and attitudes. We collected data from student and partner surveys, from interviews with the community partners, and from student reflections. By comparing student behavior and attitudes before and after this course, we have observed the following behavioral and attitudinal changes: 1) development of empathetic knowledge and understanding, 2) increased appreciation for user-centered design, 3) redefinition of career trajectories. We also saw transformations in the lives of the community partners. Outcomes for elders were related to quality of life and wellbeing and included 1) decreases in isolation, 2) increased purpose and meaning, and 3) improved feelings of wellbeing. Lasting effects included continuation of decreased isolation through a sustained increase in social engagement, as well as positive thoughts about and mechanisms for aging in place. This paper also describes the curriculum and reports on these trends over three years of coursework.

Polyhydroxyalkanoates (PHAs) are a class of biopolymers capable of which can be produced through bacterial synthesis. Many PHAs have mechanical properties similar to those found in commonly used petroleum- based plastics and, as a result, have garnered interest as a potential as a more sustainable alternative to these materials. While PHAs are biodegradable, current techniques for large-scale biosynthesis require the use of large quantities of organic solvents that do not readily degrade in water and soil. As a result, the production process may incur additional environmental impacts, despite the use of more sustainable raw materials. Thus, recycling may further reduce the impact in the production and processing of PHAs.

Green building standards like the Living Building Challenge promote the construction of net-zero energy buildings. In order to meet these standards, alternative heating and cooling methods become necessary, especially for designs with high glazing percentages. The design and analysis of a low cost heating and cooling system with 100% solar fraction is being investigated to address this scenario. Following a literature review and visits to two Living Building Challenge certified buildings, a preliminary building configuration was created for the Living Lab project at Olin College of Engineering. Thermal modeling was conducted on three basic building configurations with different amounts of solar glazing to determine the peak thermal loads for the project‘s temperate building site. Future analysis will be performed using Green Building Studio and eQuest software to identify energy saving strategies and confirm a final proposed design.

Working memory is the memory that is stored briefly and manipulated. We use it to read sentences, do math problems, and remember what a room looks like when we look away. This type of memory is severely impaired for individuals with ADHD. Working memory deficit is identified as the core cause of ADHD. Working memory deficits are correlated with poor academic performance.

Laser Cut Like a Boss aims to aid you in bringing your project vision to life by providing informative and inspirational tips and tricks to prototyping with the laser cutter. Our goal is to help you apply design and engineering thinking toward utilizing your tool to develop your project efficiently and successfully.