Tag: harvard

Harvard’s soft exosuit makes walking 23 percent easier

Harvard Wyss Institute researchers have been working on a soft exosuit with DARPA’s financial help for years. While they were able to present a proof of concept in 2016, it’s only now that they’ve found out just how much the suit can actually help its wearer. According to a new study published in Science Robotics , Harvard’s exosuit reduces the energy a user needs to exert while walking by 23 percent. It does that by providing assistive force to the ankle at the perfect moment when you take another step. Team leader Conor Walsh said that’s the highest percentage of reduction in energy use observed with an exosuit: “In a test group of seven healthy wearers, we clearly saw that the more assistance provided to the ankle joints, the more energy the wearers could save with a maximum reduction of almost 23% compared to walking with the exosuit powered-off. To our knowledge, this is the highest relative reduction in energy expenditure observed to date with a tethered exoskeleton or exosuit.” Of course, assistive force wouldn’t be as helpful without an effective design. As Wired explains, the muscles and tendons from the hip to the knee need to work together in stabilizing the leg to achieve an efficient stride. So the researchers couldn’t stop with something that only covers the ankles — they had to use garters to connect the ankle straps to a hip girdle. The result is the exosuit’s current form, which you can see below. That said, the researchers admit that they need to conduct follow-up tests. For one, they had the subjects offload the exosuit’s cable-based actuation, electronics and battery units before conducting the experiment. Those make up an additional 17-plus pounds that would have changed the wearers’ situation. Further, they found that the subjects’ gaits changed depending on how much assistive force they provided, which was between 10 to 38 percent of the ankle force needed to take a step. They still need to explore the possibility that the reduction in energy is a result of the subjects’ change in gait rather than the assistive force itself. In the future, Harvard’s exosuit could help the elderly and patients suffering from Parkinson’s, cerebral palsy and other conditions to walk well on their own. As you can guess from that DARPA funding, though, it also has a potential military application: the agency hopes it can help soldiers carry heavy supplies far longer than they’d normally be able to. [Image credit: Wyss Institute at Harvard University] Via: Wired , New Scientist Source: Harvard’s Wyss Institute

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Harvard’s soft exosuit makes walking 23 percent easier

3D printed ‘heart on a chip’ is an alternative to animal testing

3D printing’s potential to create custom objects, parts and tools has enormous potential for the medical field, where bespoke organs could be created on demand, saving lives that wouldn’t survive waiting for donors. This year has already had standout applications: back in February, scientists successfully implanted printed tissue and organs into animals while another group created a new jaw for a cancer survivor. But Harvard researchers got closer to human-ready organs when they built the first entirely 3D-printed organ-on-a-chip with integrated sensors that scientists can use to test the efficacy of their synthetic tissues, instead of inserting them in animals. The organs-on-chips, known in the scientific community as microphysiological systems (MPS), are synthetic replacements for human internals — not just hearts and livers but also bone, cartilage, microvasculature, and other tissues. But the Harvard researchers crucially integrated sensors into their MPS’s, which provide non-invasive, electronic readouts on structures within the body. The Harvard researchers developed six different “inks” into a cardiac microphysiological device — aka, a heart on a chip. The integrated sensors allowed them to bypass the typically work-intensive process of collecting data, which otherwise requires microscopy or high-speed photography. To prove the efficacy of the 3D-printed organ, they applied the MPS to study drug responses and the development of stem cell-derived cardiac tissue, as the Harvard team reported in their paper published in Nature . Using the integrated sensors, future scientists will be able to study tissue performance after they’ve been inserted. Source: Harvard press room

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3D printed ‘heart on a chip’ is an alternative to animal testing

Harvard creates a material that lets light go ‘infinitely fast’

Researchers at Harvard University announced recently that they had successfully developed a means of manipulating light at the nanoscale, which could lead to photonic-based ( rather than electronic ) telecommunications. Think, ubiquitous fiber optics. The team reportedly developed an on-chip metamaterial made from silicon pillars embedded in polymer and wrapped in gold film that exhibits a refractive index of zero. In English, that means that the phase of light passing through this material can travel infinitely fast without violating the known laws of physics. Source: Harvard University

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Harvard creates a material that lets light go ‘infinitely fast’