Research

The Global Engineering and Research (GEAR) Lab focuses on the marriage of mechanical design theory and user-centered product design to create simple, elegant technological solutions for use in highly constrained environments. Our technologies are aimed at making a positive impact on the world and elucidating novel scientific/engineering knowledge.

WATER

Village-Scale Desalination

Desalination

Due to the scarcity of fresh, potable groundwater and the unreliability of the electric grid in many parts of rural India, there is a great need for off-grid desalination systems. Current research in the GEAR Lab has been focusing on off-grid, photovoltaic-powered electrodialysis reversal (PV-EDR) desalination. Capital cost is a major barrier to the adoption of desalination technologies in India, and the power system of off-grid PV-EDR systems is the major contributor to the high capital cost of current systems. For this reason, this project is focused on designing the minimum-cost power system for EDR that can meet local water demand.The next stage of the research is building and testing a PV-EDR prototype in a village in India.


Home-Use Desalination

Home-Use Desalination

Due to the lack of reliable municipal water supply services and the increase in consumer awareness of water-borne diseases, the domestic purification industry was expected to grow at 25% compounded annually between 2012 and 2015. The per-capita consumption is also forecasted to increase nearly two-fold to 167 L/day from 2000 to 2025, the condition of water supply in India will be in a critical state. In this environment, the use of RO systems - which waste between 50 to 75% of the input water - will be undesirable. Instead, the GEAR Lab is developing an alternative solution that relies on electrodialysis (ED) to achieve a higher recovery of 90% while maintaining cost-competiveness with existing RO products in India.


AGRICULTURE

Bull-key Tractor

Bull-key

This project presents a novel tractor architecture to enable mechanization of bullock power in India. Existing tractors are inadequate substitutes for bullocks. Bullock's compact dimensions, high maneuverability, and low capital cost have allowed them to remain a popular choice for small and large farmers. These bullocks, however, are slow at covering ground, incompatible with modern precision tools, and have higher maintenance costs than tractors.


Drip Irrigation

Irrigation

The GEAR Lab is developing drip irrigation systems that can run on 10X lower pressure than conventional systems. Drip irrigation reduces water consumption by up to 60% compared to conventional flood irrigation methods. And it enables poor farmers to grow more and higher-value crops to lift themselves out of poverty. Lowering pumping pressure in an irrigation system proportionally reduces pumping power; we aim to reduce pumping power requirements to the point where solar-powered, off-grid drip systems become economically viable for the approximately one billion subsistence farmers in the developing world. Our drip technology is biologically inspired by flow restrictors found in nature, such as the bronchi found in the lungs.


ASSISTIVE DEVICES

Passive Knee

Knee Project

The focus of this project is to create a low-cost, high-performance prosthetic knee that uses only passive mechanical elements to generate a normal walking gait. The device is being designed to meet the mobility and stability needs of above-knee amputees in developing countries and offer improved performance over locked and free-swinging joints. The project includes investigating the fundamental biomechanics of transtibial amputees and codifying how changes in lower leg and foot mass affect desired knee torque and hip energy output throughout the gait cycle. Our aim is to provide similar levels of performance as high-end, active-controlled knees at a fraction of the cost, and make a prosthetic technology that will be adopted in developing and developed markets.


Prosthetic Foot

Foot Project

GEAR Lab is working with BMVSS to design an updated version of their Jaipur Foot, which is the most widely distributed prosthetic foot in the world. The original Jaipur Foot’s success was due to its lifelike look, flexibility, and extreme durability. We aim to create a new version of the foot that is much lighter, can be mass-manufactured, meets international testing standards, is compatible with other prosthetic equipment, and matches the durability of the current foot. We developed a novel prosthetic foot design objective called the Lower Leg Trajectory Error (LLTE) based on the biomechanical performance of healthy feet and on the insight we gained interacting with BMVSS. Using this objective, we are optimizing the compliance and geometry of our prosthetic foot to deliver lifelike gait mechanics using low-cost materials.


POWER

Single Cylinder Turbo

Turbo

This research is aimed at developing a novel method for turbocharging single-cylinder four-stroke internal combustion engines to create a more compact, fuel efficient and lower cost power source for small-scale farmers in India. Turbocharging uses energy from an engine’s exhaust to compress the intake air, allowing the engine to combust more fuel. Due to the pulsating nature of flow, this technology is not currently used in single cylinder engines. We have built a new style of manifold that buffers the air flow. This method has been validated through both experiments and computational models.


Hybrid Transmission

Irrigation

We are developing drip irrigation systems that can run on 10X lower pressure than conventional systems. Drip irrigation reduces water consumption by up to 60% compared to conventional flood irrigation methods. And it enables poor farmers to grow more and higher-value crops to lift themselves out of poverty. Lowering pumping pressure in an irrigation system proportionally reduces pumping power; we aim to reduce pumping power requirements to the point where solar-powered, off-grid drip systems become economically viable for the approximately one billion subsistence farmers in the developing world.


PAST WORK

LFC Wheelchair

LFC

The Leveraged Freedom Chair (LFC) is an all-terrain wheelchair designed for rural areas of developing countries. The key innovation behind the LFC is its single-speed, variable mechanical advantage drivetrain. The user propels the chair by pushing on the levers; gasping high increases torque, while grasping low increases speed. The drivetrain geometry was optimized considering human power and force capabilities, user physiology, and terrain types found in the developing world. This simple system achieves a 3:1 change in mechanical advantage, enabling LFC users to travel 80% faster and produce 50% higher peak wheel torque than they could with a conventional wheelchair. All moving parts on the LFC are made from bicycle parts found anywhere in the world, making the LFC locally repairable and comparable in price to other wheelchairs available in developing countries. The LFC is in eproduction in India and can be purchased through Global Research Innovation and Technology (GRIT).


RoboClam

Roboclam

The aim of the RoboClam project is to generate low-power, compact, lightweight, and reversible sub-sea burrowing technology. Applications for this work include dynamic and reversible anchors, littoral reconnaissance, ocean sensor placement, subsea cable installation, and self-installing oil recovery equipment. RoboClam technology is based on the digging mechanisms of Atlantic razor clams, (Ensis directus), which drastically reduce burrowing drag by using motions of their shell to locally fluidize the soil. We have successfully adapted localized fluidization burrowing into engineering applications via the RoboClam robot, which has demonstrated successful digging in both granular and cohesive soils. Ongoing work on this project is focused on articulating the parametric relationships behind localized fluidization in order to create design rules for tuning RoboClam technology to many size scales, substrates, and applications. We are currently developing a new, self-contained RoboClam that will serve as the prototype for a commercial product. We are also investigating whether RoboClam technology can be used to burrow in deep soil applications (>10 m), as well as in dry substrates.