“We wanted to scientifically demonstrate how robotic TruST can be used to deliver an intense activity-based postural and reaching training to improve the functional sitting abilities of children with CP and trunk control problems”, says Victor Santamaria, a physical therapist and associate researcher scientist in Agrawal’s Robotics and Rehabilitation Laboratory, and first author of the paper.
Recent developments in robotic equipment have enabled clinicians to address engagement, repetition, and intensity for their patients to practice task-oriented movements in CP. A team led by Agrawal, together with other researchers at Teacher’s College and the Columbia University Irving Medical Center, recently won a five-year National Institutes of Health R01 award (#1R01 HD101903-01) to conduct a randomized clinical trial.
The project—"Improving seated postural control and upper extremity function in bilateral CP with a robotic Trunk-Support-Trainer (TruST)"—will involve up to 80 children with poor trunk control. Some will use the TruST robotic rehabilitation while others will try conventional rehabilitation. This new NIH study will compare the efficacy of the motorized TruST to engage children in play-oriented practice while advancing their skill progression with static trunk support.
“Our new NIH project is a randomized clinical trial with a large sample size to study the efficacy of TruST-intervention as a unique therapeutic solution to promote seated functional abilities in children with bilateral CP,” Agrawal adds
Columbia Engineering
Columbia Engineering, based in New York City, is one of the top engineering schools in the U.S. and one of the oldest in the nation. Also known as The Fu Foundation School of Engineering and Applied Science, the School expands knowledge and advances technology through the pioneering research of its more than 220 faculty, while educating undergraduate and graduate students in a collaborative environment to become leaders informed by a firm foundation in engineering. The School’s faculty are at the center of the University’s cross-disciplinary research, contributing to the Data Science Institute, Earth Institute, Zuckerman Mind Brain Behavior Institute, Precision Medicine Initiative, and the Columbia Nano Initiative. Guided by its strategic vision, “Columbia Engineering for Humanity,” the School aims to translate ideas into innovations that foster a sustainable, healthy, secure, connected, and creative humanity.
ABOUT THE STUDY
The study is titled “Promoting Functional and Independent Sitting in Children with Cerebral Palsy Using the Robotic Trunk Support Trainer.”
Authors are: Victor Santamaria, Moiz Khan, Tatiana Luna, Jiyeon Kang, Joseph Dutkowsky, Andrew Gordon, and Sunil Agrawal, Department of Mechanical Engineering, Columbia Engineering.
The pilot study was partially funded by the Langer Foundation as administered by The Order of Malta. The authors declare no financial or other conflicts of interest.
Portable Knitted Antennas
Why knitting?
Most RF antennas, particularly highly directional array antennas like reflectarrays are planar, rigid devices. While these devices will likely always remain state-of-the-art in terms of pure performance metrics, they are often large, heavy, and unwieldy and can be expensive to manufacture. Researchers have been investigating ways to produce smaller, more flexible antennas, including inkjet printing or screen-printing directly on textiles, and embroidery. But these techniques are quasi-additive approaches in which a conductive material is added to an existing textile instead of being integrated into the textile during the fabrication process of the textile itself, introducing problems such as delamination, slip, or cracking of the metallic region, as well as issues of production scalability.
Yu’s group realized that what they needed to create was a high-throughput, inexpensive technique that directly integrates flat array antennas onto textiles. So they decided to study knitting and weaving, which, while being the most common approaches for fabricating patterned textiles, have not been explored as a way to produce complex array antennas with engineered electromagnetic responses.
A Fair Isle approach
The researchers took a novel approach to fabricating flexible, lightweight centimeter-wavelength metasurfaces. They leveraged an old-school colorwork knitting technique called float-jacquard knitting (think Fair Isle sweaters) and used commercially available metallic and dielectric yarns with existing knitting machinery to produce two prototype reflectarray devices, a metasurface lens (metalens) and a vortex-beam generating device. In the float-jacquard knitting technique, two or more types of yarn are used to produce a pattern: a yarn is floated loose beneath the fabric when not used and transferred back to the frontside as needed to create the desired pattern.
By integrating the textile fabrication and antenna patterning into a single process, the team streamlined the fabrication process and alleviated common defects in fabric-based antennas. The group is the first to adapt flat-knitting techniques to incorporate antennas directly during the fabric production procedure – integrated fabrication – and able to do it at low cost and high yield on an industrial scale. For example, each of the prototype metasurfaces with a footprint of approximately one square meter was knit within 45 minutes. In addition, the flat-knit fabric devices withstood repeated washing and stretching on a frame.
“The float-jacquard knitting technique used for making our textile metasurfaces is exactly the same technique that my mother used to make sweaters for me. I still remember a purple sweater I wore as a kid that had a row of white cats across the chest; I remember that when I inspected the inner side of the sweater, I saw white parallel yarns – the floats,” said Yu, a pioneer in researching nanophotonic devices like metasurfaces.
He noted that these complex RF antennas can be readily produced by existing infrastructure: “We can leverage the very old and very well-established knitting industry to fulfill some of the needs of modern telecommunications. The facile and scalable nature of the fabrication approach means these devices could be inexpensive, ultra-lightweight, flexible variants of sophisticated radio-frequency communications antennas.”
The results
The researchers showed experimentally that when the metalens operates as a receiving antenna, it focuses an incident centimeter-wave into a tight (diffraction-limited) focal spot, and that when it operates as a transmitting antenna, it converts the divergent emission from a horn antenna (a common RF source) into a wave with planar wavefront – a highly directional beam.
They also demonstrated that more complex wavefront shaping tasks can be accomplished: the vortex-beam generating metasurface produces a vortex beam – a beam with a corkscrew-shaped wavefront. Because of the peculiar wavefront, the vortex beam can carry an independent channel of information, thus a vortex beam and a beam with planar wavefront used together can make a communications channel twice as efficient.
Next steps
In future efforts, the researchers will explore modern knitting techniques – there are at least a dozen varieties – and knitting machines to realize more complex multi-functional designs – fabrics with combined designer electromagnetic, electronic, and mechanical responses. This could be used to engineer hinge points or folds, and electronic circuits into a fabric, which could be actuated to further facilitate stowage and deployment or even switch between different electromagnetic functionalities.
The scalability of flat knitting ranks highly among all techniques used to produce flexible or rigid RF metasurfaces and reflectarrays: commercial flat-knitting machines are capable of producing textiles up to two meters in width and with no limitation in the length direction. The researchers will explore this advantage to create high-gain antennas with apertures several meters in diameter yet lightweight and stowable to be carried by satellites to communicate across vast distances.
“It’s important to stress that these devices were fabricated using commercially available off-the-shelf yarns and leveraging established fabrication techniques,” Yu said. “I am almost certain that communities of knitters can come up with ingenious ways to integrate aesthetics and functionality into a sweater – a sweater that can double as a WiFi signal booster.”
Media Credit: Jane Nisselson
About the Study
Journal: Advanced Materials
Title: Flat-Knit, Flexible, Textile Metasurfaces
Authors: Michael J. Carter1,2, Leah Resneck3, Younes Ra'di4,5, Nanfang Yu1
- Department of Applied Physics and Applied Mathematics, Columbia Engineering
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB
- Zeis Textiles Extension, Wilson College of Textiles, North Carolina State University
- Advanced Science Research Center, City University of New York
- Department of Electrical Engineering and Computer Science, Syracuse University
Funding: The study was supported by the Science, Mathematics, and Research for Transformation (SMART) Scholarship of the US Department of Defense award to Michael Carter, and National Science Foundation grant (ECCS-2004685), awarded to Nanfang Yu. Measurements were carried out in mm-Wave Characterization Lab at the Advanced Science Research Center, the City University of New York. Devices were fabricated in the Knitting Lab (part of the Zeis Textiles Extension) at the Wilson College of Textiles, North Carolina State University
The authors have filed a provisional application for a patent with Columbia Technology Ventures based on the work reported in this article.
CRYLOGGER: Detecting Crypto Misuses Dynamically (Short Intro)
Brief Introduction to CRYLOGGER, the new open-source tool developed by Columbia Engineering computer scientists that detects unsafe security practices in Android apps
The researchers ran 1,780 popular Android apps downloaded from the official Google Play Store—the largest case study on cryptographic misuses not based on code analysis—and discovered that almost all the apps contained code or used libraries that did not strictly adhere to security standards. Many of them used broken algorithms and others adopted unsafe cryptographic practices to protect users’ data.
Each violation does not necessarily mean that an attack is possible. The rule violations should be treated as warnings to be further investigated. Some violations can be false alarms because it is very hard to precisely discriminate in all situations. The researchers contacted more than 300 developers for confirmation, but only 10 provided useful feedback.
“Many developers do not consider attacks such as privilege escalation and side-channel attacks to be possible on phones, and so they store data locally without sufficient safeguards,” notes Sethumadhavan.
The team also manually analyzed the code of 28 Android apps and found that some of the violations reported by CRYLOGGER could potentially be exploited. They see two significant applications of CRYLOGGER. Developers can use it to find cryptographic misuses in their apps as well as in the third-party libraries they use. App stores, such as the Google Play Store, can use CRYLOGGER to screen submitted apps to ensure they meet security standards and are safe for final users to download. Google already uses similar screening technologies to get rid of unsafe or scam apps and these could be extended to consider cryptographic misuses.
The researchers are working on improving the accuracy of CRYLOGGER by defining techniques that will further reduce the number of false alarms. They are also using CRYLOGGER to perform inter-app analysis so that it can analyze how apps exchange data and determine if sensitive data are kept secure. In addition, they are putting rule checking for cryptographic misuses into hardware, rather than software, to force applications to use safe practices in critical contexts.
“While we keep working to improve the accuracy of CRYLOGGER, our approach can be used by app stores to promote better security practices,” Carloni adds. “And we believe that CRYLOGGER’s technique of analyzing thousands of Android applications by running them and collecting information that can be later analyzed offline could also be used in other security domains.”
CRYLOGGER_ Detecting Crypto Misuses Dynamically
Brief preview of May 2021 presentation, explaining how CRYLOGGER detects crypto misuses dynamically. CRYLOGGER is the new open-source tool developed by Columbia Engineering computer scientists that detects unsafe security practices in Android apps.
Columbia Engineering
Columbia Engineering, based in New York City, is one of the top engineering schools in the U.S. and one of the oldest in the nation. Also known as The Fu Foundation School of Engineering and Applied Science, the School expands knowledge and advances technology through the pioneering research of its more than 220 faculty, while educating undergraduate and graduate students in a collaborative environment to become leaders informed by a firm foundation in engineering. The School’s faculty are at the center of the University’s cross-disciplinary research, contributing to the Data Science Institute, Earth Institute, Zuckerman Mind Brain Behavior Institute, Precision Medicine Initiative, and the Columbia Nano Initiative. Guided by its strategic vision, “Columbia Engineering for Humanity,” the School aims to translate ideas into innovations that foster a sustainable, healthy, secure, connected, and creative humanity.
ABOUT THE STUDY
The study is titled “CRYLOGGER: Detecting Crypto Misuses Dynamically.”
Authors are: Luca Piccolboni, Giuseppe Di Guglielmo, Luca P. Carloni, and Simha Sethumadhavan, Department of Computer Science, Columbia Engineering.
This work was supported in part by the National Science Foundation (1527821 and 1764000), a gift from Bloomberg, DARPA HR0011-18-C-0017 (System Security Integrated Through Hardware and firmware), and N00014-17-1-2010.
The authors declare no financial or other conflicts of interest.