The goal of this project is to develop a fully MRI-compatible neurosurgical robot that is capable of removing brain tumor under the direct control of a surgeon using imaging information from frequently-updated MRI. We are currently working towards developing a full-scale working prototype of MINIR by incorporating remote actuation, sensing, and control along with electro-cauterization and suction and irrigation capability. This project is in collaboration with University of Maryland School of Medicine, Baltimore.
The goal of this project is to develop experimental and computational tools to characterize the onset and progression of cancer in human breast tissue. We use contact-mode Atomic Force Microscopy (AFM) to characterize the spatial distribution of the elastic properties of benign and cancerous breast tissue specimens. To increase characterization throughput across specimens larger than the travel range of commercial AFM scanners, we have developed a customized image-guided positioning system capable of aligning the tissue specimens with the AFM across multiple magnifications. In addition, we have also developed mathematical models to quantify characterization errors arising due to the physical limits of the AFM instrumentation and calibration uncertainties.
The goal of this project is to develop mechanical characterization technique for benign and cancerous breast tissue in a high throughput manner. Contact-mode Atomic Force Microscopy (AFM), which is popularly used in quantifying material properties of biomaterials, has limitations like complex read-out electronics, bulky optics, and inability to use in opaque liquids. To overcome these problems, we have designed and developed Micro-Electro-Mechanical-System (MEMS) based Piezoresistive microcantilever force sensors with a cylindrical tip made from SU-8 polymer. These force sensors are used for detecting cancer progression in breast tissue. An array of piezoresistive microcantilever beam is envisaged to improve throughput and will be a cost-effective approach for quantifying the mechanical properties of the benign and cancerous breast tissues.
The goal of this project is to build an automated system using MEMS-baseddevices capable of measuring impedance of benign or cancerous breast tissue array simultaneously, thus increasingthe sensing throughput. We have designed and fabricated microchips having interdigital electrodesinside a SU-8 well to measure the impedance of benign and cancerous breast tissues. The benign and cancerous breast tissue core is placed in the center of the interdigital electrodes and the bio-impedance is measured. From theexperiments conducted, we found that cancerous breasttissue specimens displayed significantly different bio-impedance characteristics compared tobenign breast tissue specimens. We plan to integrate bio-impedance measurement with mechanicalcharacterization for automated sampling of breast tissue core specimens.
The goal of this project is to develop a multi-degree-of-freedom hollow needle (cannula) to account for the needle placement errors. The SMA actuators that are located at discrete locations along the length of the cannula generate steering forces and enable active trajectory corrections. This research involves SMA characterization, model-based control, motion planning and ultrasound-based tracking of the cannula.
The goal of this project is to expand the range of object shapes and sizes that can be grasped by a single manipulator. Toward that end, we have developed and patented a new grasp enhancement technology using self-sealing suction cup arrays. Many small cups can be attached to the same vacuum source and nominally self-seal. Passive reaction forces from contact with an object break the seal only on cups contacting the object, so that only those selected cups engage. All other cups remain sealed to maximize pressure differential for the engaged cups. Our design also incorporates a release mechanism using a small burst of positive pressure in the line. We are using shape memory alloy (SMA) actuators for developing a fully functional three-finger hand.