MIT Libraries: Recent submissions
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As global ambient temperatures continue to rise, with the highest recorded annual averages since 1850 being within the last ten years, problems emerge for species exhibiting temperature-dependent sex determination. This is the process by which the sex of an animal’s embryo is determined based on the temperature of environment in which it is incubated, which can result in skewed sex ratios within a population like in the case of the critically endangered Hawksbill Sea Turtles (Eretmochelys imbricata). Reportedly, 85-95% of Hawksbills sampled in the wild are currently female [3]. This sex-imbalance can negatively impact the species’ ability to procreate, leading to the potential for extinction. Currently, no viable, long-term solutions exist to effectively and safely cool sea turtle eggs while still keeping them within their natural habitat. This research proposes the creation of sea turtle egg incubators designed to achieve a temperature range that will produce a higher percentage of male hatchlings to help rectify this imbalance in habitats heavily affected by climate change. These incubators are designed to be affordable, easy to build and, most importantly, safe for the sea turtle eggs. Three-month-long temperature trials for the incubator were conducted in Jamaica with conservationist community partners at Oracabessa Bay Sea Turtle Project. Results showed that this incubator is not only easy to manufacture and use, but that it successfully regulates the temperature range in favor of more male hatchlings, while also increasing the emergence rate of the hatchlings from 70% in natural nests to over 80%. During one of the hottest months in Jamaica, the incubator, deployed without water changes, doubled the predicted percentage of males produced by natural nests. When provided with cool water changes the incubator quintupled this value. Throughout the months of August to October, the incubator achieved a temperature range that is predicted to produce 85-99% male hatchlings, thus counteracting the feminization phenomenon occurring in nature.
(Massachusetts Institute of Technology, 2025-05)Foams, widely used in packaging, insulation, protective gear, and medical implants, are versatile materials but mechanically inefficient due to their bending-dominated microstructure, leading to an exponential loss of ... -
Advancing Tendon-Driven Robotic Systems: From Climbing Robots to String Actuators
(Massachusetts Institute of Technology, 2025-05)Tendon-driven mechanisms provide a range of benefits for robotic systems, particularly by allowing actuators to be mounted at the base of a manipulator and reducing its inertia. This thesis explores two projects that exploit ... -
Coordination of distributed energy resources for a reliable, resilient, and affordable decarbonized grid
(Massachusetts Institute of Technology, 2025-05)Rapid decarbonization of the power grid is essential to meet climate goals by reducing emissions and enabling sustainable electrification of sectors like transport and heating. This requires shifting from centralized ...
