Microrobots can help detect cancer cells and drive advancement toward microsurgical applications
In recognition of the enormous potential of his pioneering research and sustained excellence in teaching, the National Science Foundation (NSF) has honored Dr. David Cappelleri, Assistant Professor of Mechanical Engineering at Stevens Institute of Technology, with the illustrious CAREER Award. As one of the most competitive programs the NSF conducts, the CAREER Award supports early career development of faculty in the sciences who are most likely to become leading researchers and teachers.
"This award is recognition by the National Science Foundation of Professor Cappelleri's past accomplishments and the promise of much more success to follow," remarks Dr. Michael Bruno, Dean of the Charles V. Schaefer, Jr. School of Engineering and Science. "Stevens is extremely proud of David's achievement, and we are committed to ensuring that his world-class research in robotics and controls continues to contribute strongly to our campus community and to the nation."
Dr. Cappelleri’s microscale robots represent a new level of sophistication. His magnetically controlled microrobots are fitted with a probe that acts as a micro-force sensor. The probe deforms as it comes into contact with cells and tissues under a microscope, and a camera system measures its deformations to allow researchers to characterize the cells or tissues based on the probe’s known properties.
The design of the micro-force sensor is inspired by traditional suspension mechanisms found in accelerometers and resonators made from silicon wafers. However, the force sensor replaces the silicon material (which would be too stiff for these purposes) with a much more compliant polydimethylsiloxane (PDMS) material. This allows researchers to measure micro-Newton forces at the scale of a biological cell with a diameter of hundreds of microns.
The micro-force sensors allow researchers to compare the stiffness of small-scale objects, and they can use this functionality to distinguish healthy and cancerous cells. The technology will also serve to improve the safety and stability of next-generation bone implants. Certain surface coatings promote adhesion of new cell and tissue growth surrounding an implant, and even reduce the adhesion of other biomaterials that could cause infection. Dr. Cappelleri’s microrobots help investigate the properties of these surfaces or coatings to help determine their effectiveness. Furthermore, by applying force in a certain manner with the microrobots, it is possible to effect positive cell reactions, allowing scientists to direct cell growth.
In the future, more dexterous microrobots will establish microsurgical applications like clearing arteries and blood clots or performing targeted drug delivery. Dr. Cappelleri also hopes to apply the technology beyond biological applications. "This area of research engenders fresh opportunities for progress and expansion into diverse industries," he says. For instance, Dr. Cappelleri is working on advanced assembly and manipulation strategies for manufacturing, in which a micro-force sensing end-effector (an end-effector is the device at the end of a robotic arm) allows micromanipulators using force-guided control schemes to position and assemble parts. This enables flexible micro-scale manufacturing with a heterogeneous team of microrobots and micromanipulators.
"Dr. Cappelleri, his colleagues, and the students to whom he will offer his expertise will ensure that Stevens plays a significant role in the future of microrobotics," says Dr. Costas Chassapis, Deputy Dean of the School of Engineering and Science, and Director of the Department of Mechanical Engineering. "The CAREER award is richly deserved and speaks to the expectancy and spirit of innovation that David brings to Stevens."
Professor Cappelleri’s colleagues at Stevens were invaluable to the maturation of his ideas, the building of proof of concept models, and the testing of his work. He is also pleased to have a subject with a rich array of applications to motivate his students. "It is greatly advantageous for students to see the product of their hard work and get the sense that their results will have an impact in real-world applications."
Dr. Cappelleri joins Stevens recent CAREER Awardees: Dr. Frank Fisher and Dr. Michael Zavlanos, of the Mechanical Engineering Department, Dr. Stefan Strauf, from Physics and Engineering Physics, Dr. Pinar Akcora, from Chemical Engineering and Materials Science, and Dr. Yingying Chen of the Department of Electrical & Computer Engineering.