A 天美影视传媒-led team has developed a box that can decontaminate N95 respirator masks using ultraviolet light. First responders use these masks to protect themselves from COVID-19 and are concerned about shortages. This way, staff can reuse masks instead of needing to use a new one each time.

The research group is currently building and distributing boxes to first-responder stations across King County. On Sept. 2 the team hosted trainings to help fire and emergency medical services staff learn how the box works, how to load masks and how to clean and service the box so that they can use it in their own stations.

The box uses UVC radiation, the highest energy of the three types of UV rays.

鈥淲hen we started this project there wasn鈥檛 anything commercially available that strictly does UVC decontamination of N95 masks and could be distributed to individual fire stations,鈥� said , UW professor of both mechanical engineering and chemical engineering. 鈥淭here are boxes that generate UVC for general decontamination, but treating N95 masks specifically for COVID-19 is a unique challenge. It requires an effective dosage distributed evenly to all surfaces of a set of masks.鈥�

The team’s box, which looks like a microwave and is about the size of a small refrigerator, can disinfect all surfaces of 15 masks at one time. The process takes about a half an hour.

The team hopes to build at least 100 boxes and is interested in eventually distributing boxes across Washington.

鈥淥ne of the most impressive parts about the project is its truly local and collaborative nature,鈥� said Posner, who is also the director of the UW鈥檚 program, which managed this project. 鈥淢any of the people involved volunteered their own personal time and resources and we truly couldn鈥檛 have done it without each and every one of them, especially the organizations who stepped up to fund the project.鈥�

This is a partnership with local health officials, first responders, manufacturers and charitable foundations, including the Medic One Foundation, UW Population Health Initiative and Medtronic Foundation.

Contact Posner (jposner@uw.edu) and UW mechanical engineering doctoral student (bensulli@uw.edu) for more information.

If a robot is sent to disable a roadside bomb 鈥� or delicately handle an egg while cooking you an omelet 鈥� it needs to be able to sense when objects are slipping out of its grasp.

Yet to date it鈥檚 been difficult or impossible for most robotic and prosthetic hands to accurately sense the vibrations and shear forces that occur, for example, when a finger is sliding along a tabletop or when an object begins to fall.

Now, engineers from the 天美影视传媒 and UCLA have developed a flexible sensor 鈥渟kin鈥� that can be stretched over any part of a robot鈥檚 body or prosthetic to accurately convey information about shear forces and vibration that are critical to successfully grasping and manipulating objects.

The bio-inspired robot sensor skin, described in a published in , mimics the way a human finger experiences tension and compression as it slides along a surface or distinguishes among different textures. It measures this tactile information with similar precision and sensitivity as human skin, and could vastly improve the ability of robots to perform everything from surgical and industrial procedures to cleaning a kitchen.

鈥淩obotic and prosthetic hands are really based on visual cues right now 鈥� such as, ‘Can I see my hand wrapped around this object?’ or ‘Is it touching this wire?’ But that鈥檚 obviously incomplete information,鈥� said senior author , a UW professor of mechanical engineering and of chemical engineering.

鈥淚f a robot is going to dismantle an improvised explosive device, it needs to know whether its hand is sliding along a wire or pulling on it. To hold on to a medical instrument, it needs to know if the object is slipping. This all requires the ability to sense shear force, which no other sensor skin has been able to do well,鈥� Posner said.

Some robots today use fully instrumented fingers, but that sense of 鈥渢ouch鈥� is limited to that appendage and you can鈥檛 change its shape or size to accommodate different tasks. The other approach is to wrap a robot appendage in a sensor skin, which provides better design flexibility. But such skins have not yet provided a full range of tactile information.

鈥淭raditionally, tactile sensor designs have focused on sensing individual modalities: normal forces, shear forces or vibration exclusively. However, dexterous manipulation is a dynamic process that requires a multimodal approach. The fact that our latest skin prototype incorporates all three modalities creates many new possibilities for machine learning-based approaches for advancing robot capabilities,鈥� said co-author and robotics collaborator , a UCLA associate professor of mechanical and aerospace engineering.

The new stretchable electronic skin, which was manufactured at the UW鈥檚 , is made from the same silicone rubber used in swimming goggles. The rubber is embedded with tiny serpentine channels 鈥� roughly half the width of a human hair 鈥� filled with electrically conductive liquid metal that won鈥檛 crack or fatigue when the skin is stretched, as solid wires would do.

When the skin is placed around a robot finger or , these microfluidic channels are strategically placed on either side of where a human fingernail would be.

As you slide your finger across a surface, one side of your nailbed bulges out while the other side becomes taut under tension. The same thing happens with the robot or prosthetic finger 鈥� the microfluidic channels on one side of the nailbed compress while the ones on the other side stretch out.

When the channel geometry changes, so does the amount of electricity that can flow through them. 聽The research team can measure these differences in electrical resistance and correlate them with the shear forces and vibrations that the robot finger is experiencing.

鈥淚t鈥檚 really following the cues of human biology,鈥� said lead author , who recently received his doctorate from the UW in mechanical engineering. 鈥淥ur electronic skin bulges to one side just like the human finger does and the sensors that measure the shear forces are physically located where the nailbed would be, which results in a sensor that performs with similar performance to human fingers.鈥�

Placing the sensors away from the part of the finger that鈥檚 most likely to make contact makes it easier to distinguish shear forces from the normal “push” forces that also occur when interacting with an object, which has been difficult to do with other sensor skin solutions.

The research team from the and the has demonstrated that the physically robust and chemically resistant sensor skin has a high level of precision and sensitivity for light touch applications 鈥� opening a door, interacting with a phone, shaking hands, picking up packages, handling objects, among others. Recent experiments have shown that the skin can detect tiny vibrations at 800 times per second, better than human fingers.

鈥淏y mimicking human physiology in a flexible electronic skin, we have achieved a level of sensitivity and precision that鈥檚 consistent with human hands, which is an important breakthrough,鈥� Posner said. 鈥淭he sense of touch is critical for both prosthetic and robotic applications, and that鈥檚 what we鈥檙e ultimately creating.鈥�

The research was funded by the National Science Foundation.

For more information, contact Posner at jposner@uw.edu.

Grant numbers NSF: CBET 鈥� 1264046 and NSF: CBET 鈥� 1461630.

For much of the world’s population, gathering fuel to cook food is a dangerous proposition. Women and children often journey miles from their homes to collect sticks and branches, exposing themselves to sexual assault, other violence and wild animals.

Inside homes across the developing world, smoke from open cooking fires and polluting cookstoves is estimated to cause and lead to a wide range of illnesses.

A more efficient and clean wood-burning cookstove 鈥� developed by the Vashon Island-based non-profit in close collaboration with 天美影视传媒 mechanical engineers 鈥� is expected to reduce the amount of fuel those families need to collect or buy by as much as 55 percent. It will also reduce the exposure of these women and children to the harmful particulate pollution produced by traditional cooking flames.

The new wood-burning cookstove will be manufactured in factory in Nairobi, Kenya beginning this summer 鈥� thanks to a recent $800,000 investment from and 鈥� and sold across East Africa.

“If women have to collect twice as much wood to cook their food, then they’re spending less time raising themselves out of poverty,” said , UW associate professor of mechanical engineering and principal investigator of the Department of Energy-funded at the UW.

“There is no real proven model for a natural-draft stove that’s efficient, looks nice, can be reliably produced and is affordable to people living in deep, deep poverty 鈥� we think this is a viable solution where no others really exist.

Compared to traditional cooking methods that balance a pot on three stones surrounded by open flame, the “Kuniokoa” cookstove is expected to reduce by 67 percent harmful particulate pollution that increases the risk of contracting asthma, heart diseases and other health problems.

It鈥檚 the first production stove to emerge from a partnership The collaboration pairs the UW’s deep expertise in combustion, fluid dynamics and heat transfer research with BURN Design Lab’s experience in designing clean, efficient and affordable stoves that are practical and popular in the developing world. The project’s third partner is the .

“What we really focus on is the usability of the stoves,” said BURN Design Lab founder and BURN Manufacturing CEO Peter Scott. “They need to be durable, they need to have a wide diameter so people can put large family pots on it. We include a tray to collect the ash so people don’t have to pick up the whole stove and shake it out, which is a really messy experience.”

The UW researchers and partners are continuing to develop a next-generation Tier 4 wood-burning stove 鈥� the highest ranking on the 鈥� scale in terms of efficiency and fuel use, total emissions, indoor emissions and safety.

The UW engineers are working on transforming a laboratory prototype that hits those metrics into an affordable production stove that can be manufactured in Africa.

“Our stoves are similar to concept cars or an F1 vehicle,” said, UW professor of mechanical engineering and co-principal investigator.

“We build systems that were never designed to go anywhere near the field because they’re too delicate and are not durable, but they tell us what’s required to get super high performance. Then we take those lessons learned and talk to BURN about how they can incorporate these ideas into their hardened and field-ready designs,” Kramlich said.

For now, the wood-burning stove that launches this summer will be sold to farmers and plantation workers on Unilever’s tea estates in Kenya and Tanzania, at a cost of roughly $35 U.S. dollars.

As a bonus, it will also be manufactured locally in Kenyan factory, which employs roughly 100 people who currently produce a separate line of clean-burning .

“This stove will be made for Kenyans, by Kenyans,” said Scott. “All the other modern cookstoves are made in China and, while there are artisanal stoves made in Africa, nobody else has a modern manufacturing facility of this kind in sub-Saharan Africa.”

For more information, contact Posner at jposner@uw.edu or 206.543.9834.

A recent published in The Lancet estimates that 3.5 million people die each year as a result of indoor air pollution from open fires or rudimentary stoves in their homes. More than 900,000 people die from pneumonia alone, which has been linked to indoor air pollution.

天美影视传媒 engineers hope to make a dent in these numbers by designing a cookstove that meets a stringent set of emission and efficiency standards while still being affordable and attractive to families who cook over a flame each day. The team received a $900,000 grant in September from the U.S. Department of Energy to design a better cookstove, which researchers say will use half as much fuel and cut emissions by 90 percent.

“We are taking a holistic approach to designing a stove that will be clean and efficient, and also meet the needs of the people who are cooking,” said project lead , a UW associate professor of mechanical engineering. “Our goal of bringing cleaner wood-burning stoves to the developing-world market can only be met if we have an attractive product that meets key price and usability needs.”

The health risks and environmental impacts from solid-fuel cookstoves have only recently been studied and documented. In 2010 the United Nations Foundation, kick-started by then-U.S. Secretary of State Hillary Clinton, launched the , a public-private partnership that is trying to get clean cookstoves and fuels to penetrate 100 million households by 2020.

In addition to creating an efficient stove, the UW researchers will also develop software that will allow other cookstove designers and manufacturers 鈥� especially those in the developing world 鈥� to test different elements as they make stoves to fit the needs of various communities around the world.

“The goal is not to just generate a design that is copied, but to provide a tool that allows others to design more efficiently on their own,” said , a UW professor of mechanical engineering who is leading the project’s combustion testing and modeling.

Modeling can be used to screen a large number of design ideas and find those that offer the highest payoff, Kramlich said.

Health factors aren’t the only issues with poorly designed cookstoves. Inefficient stoves also have environmental impacts, including contributing to deforestation and global warming through added particulates in the air. They also fuel gender inequality, Posner said, because it’s usually the women in each community who spend hours each day collecting wood and are exposed to smoke while cooking.

The UW-led team signed a contract with the Department of Energy’s Office of Energy Efficiency and Renewable Energy and plans to start the three-year project this fall. The team includes a variety of organizations with different specialties, including on Vashon Island, Wash., global health nonprofit in Seattle, and in Berkeley, Calif.

At the UW, engineers will try to reduce smoke emissions and improve efficiency while designing a stove for East African communities that is inexpensive to manufacture. This will cut down on the amount of wood needed to cook and improve the air quality for families using the stove. The design likely will have simple parts and use natural drafts to move air through the stove, Kramlich said.

Perhaps most importantly, the stove must be familiar enough in design so people will want to use it, said Peter Scott, founder of Burn Design Lab.

“While there’s a place for high-tech stoves, for Africa and the developing world it’s important to have a robust design without a lot of moving parts,” Scott said. “Having this partnership will directly translate to a finished product in the market in three or four years.”

Designing cookstoves that are good for human health and the environment 鈥� and that take into account the social and economic needs of each community 鈥� is an interdisciplinary feat, Posner said. He hopes the UW can develop a research institute that brings in many departments and schools such as public health, sociology, law, business and medicine to tackle the problem.

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For more information, contact Posner at jposner@uw.edu.