July 13, 2020
Congratulations to Rui Yin for passing his qualifying exam!
June 17, 2020
Congratulations to Haiyi Long for winning a Master’s Scholar Award from the Department of Materials Science, supporting her continued work on soft composites!
May 27, 2020
Congratulations to Hiromi and Lucia for publishing the group’s latest work in Phys. Rev. Applied. In this work we studied the dynamics of highly-nonlinear structures consisting of a soft “rotating squares” geometry with embedded magnets. When a load is applied the squares are free to rotate, but may suddenly snap together as the magnets get close enough to interact. These different orientations of the squares have some relation to different “phases” in materials. If one square “changes phase” it undergoes significant rotation, which will influence its neighbors. This phase change can thereby propagate through the structure, and even interact with other transition waves to form stationary domain walls (see image below). Please see our article to learn more about the rich physics we observed in these systems: “Transition waves and formation of domain walls in multistable mechanical metamaterials” [see pdf].
May 22, 2020
Congratulations to Chengyang and Yijie for publishing the group’s latest work in J. Mech. Phys. Solids. While lightweight structural composites have been the subject of a great deal of research in recent decades, and are now regularly used in the aerospace and automotive industries, soft composites have received comparatively less attention. Yet such materials are ubiquitous in nature. They are important to understand for their many roles, which range from pathologies in the human body to the movement of soft robots. The comparatively high deformability of soft materials leads to complex strain states, and the addition of fiber reinforcement complicates the picture even more, especially when it comes to understanding the mechanisms of failure in these complex materials. In this work, we combined experimental methods, and particularly the use of multiscale digital image correlation (see image below), with a mechanistic model and a phenomenological continuum model to understand how and why soft fiber composites fail during large deformation (in this case due to the fiber reinforcement debonding from the matrix). “Spatial programming of defect distributions to enhance material failure characteristics” [see pdf].
February 1, 2020
Once again this year our group participated in Philly Materials Day by running a table called “The Utility of Instability”. More than 900 people from the Philadelphia area attended this year!
February 1, 2020
Welcome to Haiyi Long (master’s student), Maha Masud (undergraduate), and Arjun Shukla (undergraduate) who have joined the group!
January 20, 2020
We presented at the Gordon Research Conference on Multifunctional Materials and Structures in Ventura, CA this week. Thanks to the organizers for the invitation to present our work! A fantastic conference.
December 13, 2019
Hiromi has made a video about research and life at Penn in 2019:
December 11, 2019
Thanks to Max for all is his work in 2019! Unfortunately for us he is graduating. Congrats on finishing the Master’s degree, Max!
November 14, 2019
Congratulations to Chengyang on publishing the group’s latest work in Extreme Mechanics Letters. One of the well-known problems with 3D printers is that they produce characteristic defects throughout the structure, an inevitable byproduct of building up a structure via incremental addition of material. While many have tried to minimize such defects, they are always there to some degree. Rather than trying to fight this, in this innovative work we use systematically-arranged defects to control the movement of cracks in the material during failure. This leads to the counterintuitive idea that weak interfaces and defects can in fact enhance failure characteristics of a material system. This principle is observed widely in natural materials like bone, wood, shell, etc. “Spatial programming of defect distributions to enhance material failure characteristics” [see pdf].
November 12, 2019
This week we are at the American Society of Mechanical Engineer’s main annual conference (IMECE), this year in Salt Lake City. Our group’s work is again being represented in five different conference talks, and we are co-organizing the Symposium on Mechanical Metamaterials.
October 14, 2019
We are at the Society of Engineering Society’s annual conference, this year in St. Louis. Our group’s work is being represented in five different conference talks, and we are co-organizing the Symposium on 3D/4D Printed Functional Materials and Structures.
September 25, 2019
Along with the Arratia and Durian groups at Penn, our group has been awarded a Major Research Instrumentation (MRI) grant from the National Science Foundation to construct a confocal microscope rheometer. This will allow our group not only to characterize the rheological behavior of new materials for 3D printers, but also to observe how the microstructure evolves during the printing process. We are grateful to NSF for the support.
September 23, 2019
Congratulations to Yijie on publishing the group’s latest work in Advanced Materials Technologies. In this work, we develop renewable 3D printable fiber composites from 100% natural materials, including a sticky rice (amylopectin)-based matrix and cotton fibers. “3D printing of amylopectin-based natural fiber composites” [see pdf].
August 28, 2019
We are sad to see the end of summer, and with it farewell to Olivia, Brian, and Ethan, who joined us for the summer. Thanks for all your work this summer!
July 31, 2019
With a sincere thanks and congratulations, we sadly say farewell to Yijie, who is leaving Penn to start a faculty position at the University of North Texas. Thanks for your work in our lab, and best of luck during the transition!
July 10, 2019
Congratulations once again to Chengyang on publishing our latest work, in the journal Physical Review Letters. In this work, conducted together with our colleagues from Harvard and CNRS, we study the propagation of an impulse through a 2D metamaterial in which the geometry produces a strong nonlinearity leading to elastic vector solitons. Of particular note in this work is the strong effect of the material anisotropy on the propagation of the wave. For typical impact angles, two modes are observed. At specific impact angles there are exceptions to this (see images below). E.g., at impact angles of 45 degrees relative to the principal axis we observe focusing of the wave, indicative of “sound bullets”. “Focusing and mode separation of elastic vector solitons in a 2D soft mechanical metamaterial” [see pdf].
July 2, 2019
Congratulations to Chengyang on publishing the group’s latest work in Physical Review E, in collaboration with Prof. Purohit. The work studies the propagation of nonlinear waves through soft metamaterials based on a “rotating squares” geometry. “Cnoidal wave propagation in an elastic metamaterial” [see pdf].
June 14, 2019
Welcome to Rui, a new materials science PhD student joining the group this summer!
June 12, 2019
Congratulations to Max for receiving a well-earned 2019 MEAM MSE Merit Scholarship for his ongoing research in the group!
June 11, 2019
We thank Penn-Health Tech for a new award to support our collaboration with Dr. Hong on 3D printed pessaries.
June 8, 2019
Our lab has been awarded a new grant from the Air Force Office of Scientific Research. This will support our research on smart soft actuators that autonomously respond to their environment. We thank AFOSR for this support!
June 4, 2019
Welcome to Olivia, a new undergraduate summer researcher!
June 3, 2019
We attended the Phononics 2019 conference in Tucson. Thanks to the organizers for a great conference and the invitation to present our work.
May 2, 2019
Prof. Raney presented a seminar at the Johns Hopkins Department of Civil Engineering. Thanks to Profs. Guest and Gaitanaros for the invitation!
April 30, 2019
Prof. Raney receives a 3M Non-Tenured Faculty Award! We thank 3M for the support of our group’s research.
April 26, 2019
Congratulations to Sona, Will, and Kiera for winning 1st place in the Materials Science Senior Design competition! Their team (Sole3D) worked in our lab to develop conductive, soft sensors for use in the soles of shoes. This technology could help with diagnosis of gait issues in sports and medicine.
April 8, 2019
Congratulations to Jimmy for winning 1st place for his presentation at the AIAA regional student conference!
April 3, 2019
We are co-organizing the Symposium on Architected Materials at the 2019 Mach conference in Annapolis, MD.
March 14, 2019
Prof. Raney presented a seminar at Drexel. Thanks to Prof. Najafi for the invitation!
February 2, 2019
Members of the Architected Materials Lab ran a demo table called The Utility of Instability at Philly Materials Day, a great outreach event to the surrounding community. Thanks to Yijie, Lucia, Chengyang, and Max for taking part!
January 24, 2019
Welcome to Jimmy, a new undergraduate student in the group
January 10, 2019
See our latest work published in Nature Communications. Congratulations to Yijie and Lucia! “Bifurcation-based embodied logic and autonomous actuation” [download pdf]
For more information, see our blog post on the Nature Community website.
This work was also featured as part of the Y-Prize last fall, with further information available here and in the video below (see update on Sept. 14, 2018).
January 7, 2019
Welcome to Dr. Hiromi Yasuda, a new postdoctoral fellow in the group!
December 22, 2018
Congratulations to Matt for completing his master’s degree at Penn! We are very sorry to see you moving away. Thanks for all your hard work in the group during your time at Penn.
November 30, 2018
Chengyang and Yijie are presenting at the fall Materials Research Society (MRS) conference being held in Boston, MA.
November 9, 2018
Chengyang and Yijie are presenting at the annual ASME IMECE conference being held in Pittsburgh, PA.
October 1, 2018
Our lab is being awarded two new seed grants from Penn’s NSF MRSEC. The first of these will allow us to study mechanical failure in fibrous networks and composites. The second, a collaboration with Prof. Celia Reina and Prof. Prashant Purohit, focuses on the study of nonlinear wave phenomena in structured media.
September 20, 2018
Congratulations to Lucia Korpas for receiving a GAANN Fellowship!
September 14, 2018
See our work featured as part of the Y-Prize competition at Penn:
August 23, 2018
Congratulations to Lucia Korpas for passing her PhD qualifying exam!
June 1, 2018
Congratulations to Chengyang Mo for passing his PhD qualifying exam!
May 30, 2018
Congratulations to Matt Sorna for receiving a 2018 MEAM MSE Merit Scholarship for his ongoing research!
April 6, 2018
We are co-organizing the Symposium on Architected Materials at the 2018 Mach Conference, being held in Annapolis, MD and sponsored by the Johns Hopkins Extreme Materials Institute.
January 23, 2018
See our latest work published in Advanced Materials and performed with colleagues at Harvard and ETH Zurich. “Architected lattices with high stiffness and toughness via multicore-shell 3D printing” [download pdf]
January 18, 2018
See our latest work published in Proceedings of the National Academy of Sciences and performed with colleagues at Harvard, the University of Tennessee, and ETH Zurich. “Rotational 3D printing of damage-tolerant composites with programmable mechanics” [download pdf]
October 15, 2017
Welcome to Matt Sorna, a new Master’s student in the group!
August 28, 2017
Welcome to Lucia Korpas and Sunder Neelakantan, two new PhD students in the group!
August 4, 2017
Welcome to Chengyang Mo, joining the group as a new PhD student!
July 25, 2017
We are co-organizing the Symposium on the Mechanics of 3D Printed Materials at the 2017 SES conference, being held in Boston, Massachusetts.
June 19, 2017
Welcome to Hanming Zu, Vighnesh Vijay, and Cindy Huang, who have joined us for the summer to do undergraduate research!
May 18, 2017
See our latest work in Physical Review Letters, published with colleagues from Harvard and CNRS. “Elastic vector solitons in soft architected materials” [download pdf]. This is featured as an Editors’ Suggestion.
April 17, 2017
The construction of our permanent labs has been completed! Our new spaces are on the fourth floor of Penn’s Laboratory for Research on the Structure of Matter.
April 6, 2017
We are co-organizing the Symposium on Architected Materials at the 2017 Mach Conference, being held in Annapolis, MD and sponsored by the Johns Hopkins Extreme Materials Institute.
March 16, 2017
Welcome to Dr. Yijie Jiang, who is joining our group as a post-doc (having recently finished his PhD at Penn!)
February 13, 2017
See our latest work in Bioinspiration & Biomimetics and performed with colleagues at Harvard and MIT. “Lightweight 3D cellular composites inspired by balsa” [download pdf]
February 12, 2017
Our group is featured by Penn Engineering: link
January 14, 2017
Together with colleagues from Caltech, Harvard, and ETH Zurich, our work on transition wave propagation in soft media is being funded by a new award from the Army Research Office!
October 30, 2016
We are presenting our work at MIMS16, a multiscale materials workshop being held in Cetara, Italy.
October 2, 2016
We are presenting our work at the Society of Engineering Science annual meeting, being held at the University of Maryland College Park.
September 1, 2016
Welcome to Avinash Sooriyarachchi (Avi), joining the group as a new PhD student!
August 8, 2016
See our latest work in Proceedings of the National Academy of Sciences and performed with colleagues at Harvard and Caltech. “Stable propagation of mechanical signals in soft media using stored elastic energy” [download pdf]
August 1, 2016
The Architected Materials Laboratory is starting at the University of Pennsylvania! We will be conducting our research in temporary space in the Singh Center at Penn while our permanent space is being constructed.