We-Lab offers Wellesley students the opportunity to engage in research associated with engineering during the semester and in the summer. Most opportunities are for independent study; there are occasional possibilities for funding, generally in the summer. Please contact Amy Banzaert for details, firstname.lastname@example.org.
Fall 2018 SERP
As digital fabrication tools (such as laser cutters and 3D printers) become increasingly accessible, affordable and usable, the opportunity to innovate with them expands. In this interdisciplinary project, the SERP student will work with Professor Amy Banzaert (Engineering) and Professor Ann Trenk (Mathematics) in designing and creating models for hands-on activities in Mathematics ( e.g demonstrating the Pythagorean theorem using tangram-like pieces). The student will also participate in related outreach activities at Wellesley College and in the community, in maintaining We-Lab and assist in preparing an article about this work for a journal in engineering education.
Summer 2017 Research Projects
Developing a Drone Payload Delivery System for ENGR305/PEAC305:
Intersections of Technology, Social Justice and Conflict
Sarah Chu, ‘20, Jiaming Cui, ‘19
Unmanned aerial vehicles, commonly known as drones are innovative technologies that have notable implications for social justice and conflict. This project focuses on developing a payload delivery system to be used in Wellesley's new ENGR 305 / PEAC 305 course to enable students to gain a deeper uderstanding of drone technology and its societal implications.
A payload delivery system was designed, built, installed and tested on the DJI Phantom 3 Professional drone. This system is able to carry a variety of payloads and release them upon command in mid-air. The payloads tested for this project are conceptual representations of real-life cargo and rescue devices; they included a wiffle ball, a rubber ball and 3D printed boats. For this work, several methods for dropping a payload on comman were researched, designed, prototyped and refined. The final device consists of four parts; a servo motor that rotates to translate a retractable rod, a receiver, a battery and a 3D printed mounting plate that holds all components to the drone and interlocks with the retractable rod. The 3D printed plate attaches to the drone frame, which originally supported the camera. A stock transmitter is used to activate the servo when the payload release is desired. The device was tested successfully on a flying drone to prove its functionality with multiple payloads. Future work will concentrate on building a ore stable attachment between cargo and the payload device utilizing the drone wiring to control the servo directly.
Preliminary study of Health and Safety Hazards posed by Laser Engraver Fume Emissions in Makerspaces
Jiaming Cui, ‘19
Laser engraving machines are widely used in educational and community makerspaces nationwide. At Wellesley College, a Trotec laser engraving machine located in the Wellesley Engineering Lab (We-Lab) is heavily used by students and faculty for a variety of fabrication projects. The assumption in using this equipment is generally that the ventilation unit of the engraver was sufficient to prevent health and safety hazards.
However, air quality concerns in the We-Lab led to an industrial hygiene survey of the laser cutter, which revealed that the laser cutter can generate airborne concentrations of particles and gases that could collectively be responsible for respiratory tract irritation. This project offers a preliminary study of laser engraver fume emissions in makerspaces, communal workspaces that serve similar purposes as Wellesley College Engineering Lab.
A background search provides justifications for further study of the topic: Although there are previous studies of laser cutters fume emissions in industrial and medical environments and studies of 3D-printer fume emissions in makerspaces and consumer contexts, no prior research on laser cutter fume emissions in makerspaces has been found; furthermore, many compounds generated by cutting plastics and composite woods –commonly-used materials in makerspace laser engraving – are quantified with irritant health effects. The occupational exposure standards and health effect information were collected for three major categories of airborne chemicals: Ultrafine Particles, Particulate Matter and Volatile Organic Compounds. The comparison between exposure limits and compound concentrations detected suggests concerning health effects of several chemicals. Statistical visualization and analysis of ultrafine particle numbers during different stages of engraving suggest correlation between number of particles and whether the lid of the machine is open. An outline of a paper that summarized all findings has been produced. Future work will concentrate on modeling the change in number of particles with particle sizes and the state of the engraver lid and completing a paper on this preparatory study to provide health and safety recommendations for makerspaces that operate laser engravers.
Community Rowing Inc. & the Wellesley Engineering Lab: Providing New Technologies for Para Rowers
Linda K. Lazo '18
Community Rowing Inc. is a nonprofit dedicated to making rowing accessible to everyone, including those with physical and cognitive challenges. CRI has a dedicated coaching and volunteer staff trained to work with adaptive athletes “using specialized equipment designed to meet the needs of adaptive rowers.” Amy Banzaert, Lecturer and Director of Engineering at Wellesley College, has partnered with CRI to assist with the design and implementation of specialized equipment for adaptive athletes. During the summer of 2017, two projects were refined from prior work by students in ENGR111: Product Creation for All and independent studies.
The first project, the Erg Grabber, was developed to help para rowers with limited trunk mobility to use the erg machines independently when training using a fixed seat. Without this device, para rowers must wait on a coach to help them reach the erg handle before and after they finish their workout and control the erg monitor. The Erg Grabber is a reaching tool that allows fixed-seat rowers to grab and release the erg handle without assistance, and allows them them to control the erg monitor through a button on the bottom of the grabber. This summer, the manufacturing process for the Erg Grabber was refined to ensure that the hooks that are used to grab the erg handle, which require tight tolerances to function properly, can be repeatedly and properly manufactured by laypeople. Six erg grabbers were manufactured and drop tested, and the manufacturing process was documented in a manual intended for laypeople.
The Rigger Raisers were created for para rowers who need fixed seats in their boats when rowing, thereby sitting higher on the boat than is typical. This position reduces the distance between the rower’s arms and the oar itself, an uncomfortable orientation that greatly reduces a rower’s ability to deliver maximum power to the oars due to ergonomic considerations. Rigger Raisers are a type of scissor lift -- one on each side of the boat -- that can easily and simultaneously raise the oars to the desired height to improves the rower’s performance and comfort. This design offers a solution that can be tailored to different needs without modifying the boat. The Rigger Raiser design was completed this summer by finalizing the framework for each scissor lift design, including critical details such as spacers/washers (and also recognizing the need to accommodate each prototype due to natural variation). This project also involved the use of SolidWorks Simulation: a software that facilitates creating 3D models of devices and evaluating likely outcomes caused by external forces. The Rigger Raiser was modeled and tested under a load of 250N, estimating stress, strain, and displacement. Based on this model, the Rigger Raiser is not expected to fail under anticipated use conditions. The manufacturing process was documented in an accessible manual for this project as well.
These projects were successfully developed and delivered to Community Rowing Inc. the week of July 10, where they were well-received. This partnership provides a unique opportunity for Wellesley College students to practice real-world engineering and for CRI affiliates to benefit from new prototype equipment.
Testing & Developing Water Pump Modules for ENGR305/PEAC305: Intersections of Technology, Social Justice, and Conflict
Sarah Chu '20
The objective of this project was to identify and develop water pump models to help students enrolled in Wellesley’s new ENGR305/PEAC305 course grasp the design and functionality of two different water pumps in a hands-on manner. The section of Prof. Louis Bucciarelli’s MITx introductory course 0.123x Liberal Studies in Engineering entitled “Techno-Anthro Two Pumps” was studied prior to testing and creating modules. Two types of pumps were analyzed: the Zimbabwe Bush Pump ‘B’ type, a standard displacement hand pump, and the PlayPump, which uses a circular, sinusoidal cam to pump water. Four different scale models of hand pumps, manufactured originally as toys and small functional devices, were tested to evaluate their applicability in understanding the functionality of the Bush Pump. Two out of the four were selected for sufficient transparency and clarity for the technology. Testing revealed certain water pumps required submersion at specific depths to displace the largest output of water.
Since models of the PlayPump do not exist, a simplified version of the PlayPump was designed, prototyped, and refined. The design process consisted of researching the pump functionality by sketching pump components and building a paper model of the pump followed by a cardboard model. Each of these stages provided insight into the design and flaws of every respective model. A final model, which successfully communicates the pump’s function, was developed. The finished product has the following components: a PVC pipe, a laser-cut outer collar attached to the PVC pipe, a sinusoidal cam resting on the outer collar, a laser-cut wheel attached to the cam, a vertical T representing the piston valve, and two laser-cut circular discs that constrain the vertical T. As the wheel turns, the T resting on top of the sinusoidal cam moves in a vertical motion, representing the movement of a real-life PlayPump.
Summer 2013 Research Projects
Nearly half of the developing world depends on the use of biomass, including wood and wood charcoal, for cooking. Burning biomass in the kitchen creates indoor air pollution, which is the cause of death for close to 1 million people. While the use of wood charcoal (WC) would cut these deaths in half, the environmental impact of switching from wood to wood charcoal would be devastating. This tension has inspired the search for an alternative cooking fuel with health impacts comparable to wood charcoal but reduced environmental impact. One proposal is agricultural waste charcoal (AWC), which is produced by the carbonization of agricultural wastes including sugarcane bagasse, a byproduct of the harvesting of sugar. Previous research conducted by Amy Banzaert has compared AWC and WC based on their combustion emissions, but they have not been compared formally to evaluate which is less damaging to the environment.
A life cycle assessment (LCA) was created in order to quantitatively evaluate the impacts of WC and AWC on the environment. LCA is a “cradle-to-grave” method that considers the inputs and outputs for each of all four stages of a product’s life – raw materials acquisition, manufacturing, use, and disposal – and evaluates the cumulative environmental impacts that result from them.
Based on the IMPACT 2002+ methodology, AWC has a positive impact in the category of global warming. Although the impact is modest, choosing AWC instead of WC would serve to mitigate climate change processes. As expected, wood charcoal’s greatest negative environmental impact is in terms of land occupation, where tree harvesting and the carbonization process contribute most substantially. Based on weighted results, we reached the preliminary conclusion that although AWC and WC are both harmful in terms of their impact on human health, the environmental benefits outweigh the human health effects, making AWC a viable fuel to WC.
Approximately 3 billion people – nearly half of the world’s population – use solid fuels such as wood and charcoal for cooking and heating. Annually, 2 million people die prematurely from illnesses associated with indoor air pollution from cooking fuels; many more have suffered significant decreases in their quality of life due to disabilities exacerbated by such conditions. While much research has been conducted to quantify the extent of harmful emissions that these people may be exposed to, there is a need for a reliable, accurate, and affordable process for calculating this.
This project focused on developing a procedure and universal enclosure to measure emissions from cooking fires in an affordable and repeatable
manner. Tests were run to learn the behavior of carbon monoxide emissions. Carbon monoxide was chosen as a representational proxy for other harmful smoke emissions. To simulate real conditions, a kerosene fueled fire was burned in a ventilated tent while carbon monoxide concentrations were actively logged during and after the burn. Tests were run to understand the measurability of carbon monoxide based on the effects of ambient temperature, humidity, wind conditions, and proximity to the fire. The results showed that humidity and ambient temperature had minimal to no effect on the measurability of carbon monoxide emissions while wind conditions and proximity to the fire did. Gusts of wind blowing away from the sensor yielded lower CO measurements while winds blowing against sensors measured higher CO concentrations. Wind conditions also changed the effect of proximity of sensors to the fire: above 2km/h wind speed, wind direction had more influence on measurements then proximity did.