Human-centered Electric Prosthetic (HELP) Hand

Through a partnership with Indian non-profit Bhagwan Mahaveer Viklang Sahayata Samiti, we designed a functional, robust, and and low cost electrically powered prosthetic hand that communicates with unilateral, transradial, urban Indian amputees through a biointerface. The device uses compliant tendon actuation, a small linear servo, and a wearable garment outfitted with flex sensors to produce a device that, once placed inside a prosthetic glove, is anthropomorphic in both look and feel. The prosthesis was developed such that future groups can design for manufacturing and distribution in India

Influence: Art, Activism, and Identity as Seen Through a Neurodivergent Lens

My world has no separation between art, activism, and identity. As a neurodivergent individual, I experience life through hyperactive senses. It is an intense reality; however, it is the force that drives me to create, explore, discover and learn. My mind works like a kaleidoscope, always awash in colorful abstract images, each twist or turn reveals a new perspective. For my MFA visual art thesis, I used my neurodivergent brain as the foundation of my study. The concept formed in my mind first as blurry shapes and colors, and then came into focus as I began the process of gathering and testing materials. Eventually, I was able to replicate the images in my mind, converting them into actuality with yarns, fibers, plastics, latex, and light. The physical results of this process are six lopsided, vibrant, soft sculptures based on neurons. They hang suspended and interwoven, interacting with one another in the gallery space as an installation, similar to the way neural networks connect. By sharing my divergent artistic perspective and backing up my narrative artwork with scientific data and medical research, I hope to dispel harmful myths and foster a better understanding of the challenges that neurodivergent individuals experience. I want my art to spark productive conversations about ways we can reform our educational and societal systems to be more inclusive and open to all people. Ultimately, I would love to see my work widen the way, so that anyone who follows the divergent path after me will encounter less resistance

2020 Student Symposium Research and Creative Activity Book of Abstracts

The UMaine Student Symposium (UMSS) is an annual event that celebrates undergraduate and graduate student research and creative work. Students from a variety of disciplines present their achievements with video presentations. It’s the ideal occasion for the community to see how UMaine students’ work impacts locally – and beyond. The 2020 Student Symposium Research and Creative Activity Book of Abstracts includes a complete list of student presenters as well as abstracts related to their works

Experimental Analysis of Smart Tires

A novel smart tire monitoring system was designed and implemented on a fully functional car tire. Polyvinylidene fluoride (PVDF) based piezo-electric sensors were embedded inside rubber tire to measure strain related data. System electronics were implemented inside a robust IP-68 (Ingress Protection) rated enclosure. This enclosure was mounted on a car wheel and successfully recorded sensory data onto an SD card during driving. Data collected from the PVDF sensors were then post-processed in Matlab. An artificial neural network (ANN) was built to correlate the sensor data to the readings given by an industry grade load wheel. Although the correlations are very crude, this study shows a promising way to analyze the strain related information from car tires by using PVDF sensors in conjunction with ANNs. This strain related information can then be used to estimate six different values concerning the tire, namely lateral force (Fy), longitudinal force (Fx), normal force (Fz), aligning moment (Mz), inflation pressure and friction coefficient. All of which are very important parameters for vehicle dynamics. However the estimation of these values is not presented within the context of this work. Two low cost data acquisition systems were designed in-house with two different Arduino platforms. However these fell short of data acquisition performance requirements required for realistic driving applications. It was seen that the Arduino family, low-end microprocessors, were not the best choice for applications of this nature. Finally electronic improvements such as the usage of field programmable gate arrays (FPGA) is discussed and suggested for future works

Doctor of Philosophy

dissertationOptical methods are well-established in the fields of neuroscience, medical imaging, and diagnostics, etc. Optogenetics, for example, enables molecular specificity in optical neural stimulation and recording and has been named the "Method of the Year 2010" by Nature Methods. A novel microdevice was designed, fabricated, developed, and tested to facilitate three-dimensional (3D) deep-tissue light penetration with the capacity to accommodate spatiotemporal modulation of one or more wavelengths to advance a broad range of applications for optical neural interfaces. A 3D optrode array consisting of optically transparent "needles" can penetrate >1 mm directly into tissue, thereby creating multiple independent paths for light propagation that avoid attenuation due to tissue absorption and scattering, providing a high level of selectivity and comprehensive access to tissue not available in current interfaces. Arrays were developed based upon silicon and glass. The silicon optrode array is based upon the well-established Utah electrode array architectures and is suitable for near-infrared (NIR) applications; glass optrodes are appropriate waveguides for both visible and NIR wavelengths. Arrays were bulk-micromachined with high-aspect ratio, a process that has not been reported to be applied to glass previously. In addition to device fabrication, extensive laboratory testing was performed with various optical sources to determine loss mechanisms and emitted beam profiles in tissue across the relevant wavelength ranges, with particular focus on performance metrics for optogenetic and infrared neural stimulation applications. Optrode arrays were determined to be amenable to integration with typical neural stimulation and imaging light delivery mechanisms such as optical fibers and microscopes. Glass optrodes were able to transmit light at ~90% efficiency through depths many times greater than the tissue attenuation length, with negligible light in-coupling loss. Si optrodes were determined to be only ~40% efficient with losses mostly from high index contrast, tip backreflection, and taper radiation. The in-coupling technique and optrode geometry may be modified to produce illumination volumes appropriate for various experimental paradigms. While the focus of this work is on optical neural stimulation, optrode array devices have application in basic neuroscience research, highly selective photodynamic therapy, and deep tissue imaging for diagnostics and therapy

Recent progress in extrusion 3D bioprinting of hydrogel biomaterials for tissue regeneration: a comprehensive review with a focus on advanced fabrication techniques

Over the last decade, 3D bioprinting has received immense attention from research communities for developing functional tissues. Thanks to the complexity of tissues, various bioprinting methods are exploited to figure out the challenges of tissue fabrication, in which hydrogels are widely adopted as a bioink in cell printing technologies based on the extrusion principle. Thus far, there is a wealth of the literature proposing the crucial parameters of extrusion-based bioprinting of hydrogel biomaterials (e.g., hydrogel properties, printing conditions, and tissue scaffold design) toward enhancing performance. Despite the growing research in this field, numerous challenges that hinder advanced applications still exist. Herein, the most recently reported hydrogel-based bioprinted scaffolds, i.e., skin, bone, cartilage, vascular, neural, and muscular (including skeletal, cardiac, and smooth), are systematically discussed with an emphasis on the advanced fabrication techniques from tissue engineering perspective. Methods covered include the multiple-dispenser, coaxial, and hybrid 3D bioprinting. The present work is a unique study to figure out the opportunities of the novel techniques to fabricate complicated constructs with structural and functional heterogeneity. Finally, the principal challenges of current studies and a vision of future research are presented

Development and evaluation of a body weight support treadmill for use with locomotor training on pediatric spinal cord injury patients.

The consequences of spinal cord injury (SCI) are devastating regardless of the age of a patient. When the injury occurs in children five years old or younger, however, the impact is magnified due to the inevitable development of scoliosis (96%) and hip dysplasia (57%) (Schottler et al., 2012). To reduce occurrence of these complications and improve the quality of life for these patients, specialized activity-based therapies such as locomotor training (LT) are being increasingly used to improve overall trunk control and muscle activity in the lower extremities (Harkema et al., 2012; Howland et al., 2014). The aim of this therapy is to activate the neuromuscular networks below and across the level of the lesion via intense practice and repetition of the task of walking and standing. To conduct LT, the re-training of the neuromuscular network occurs during training on a specialized treadmill with an integrated system for monitoring, controlling, and recording the patient’s body weight support (BWS) (via a patented force feedback system) and manual trainers that promote a task-specific, sensorimotor experience. While body weight support treadmills (BWST) exist for LT with adults, none have been developed specifically for children. Adult systems are neither suited to the needs of the pediatric population, nor to the needs of the physical therapist and trainers providing the therapy. This thesis reports on the development of a body weight support treadmill specifically designed to enable pediatric LT. Evaluation of this prototype will lead to further system development with the end goal to develop a marketable clinical ready body weight support treadmill for use with the pediatric population

Analysis of aggregate mineralogy using LIBS

The New Jersey Department of Transport (NJDOT) has a vested interest in the determination of the chemical composition and thereby the mineralogy of aggregates. Depending on the mineralogy of an aggregate sample, it may be inappropriate to use for construction and roadwork purposes. Current methods of determining the mineralogy of aggregates are costly in terms of time, money and convenience. As such, there is a desire for the development of an alternative and efficient method for aggregate mineralogical determination in the field. The focus of this study is to develop a portable system for aggregate analysis in the field and compare the results with X-Ray Fluorescence (XRF) data provided by the NJDOT. Laser Induced Breakdown Spectroscopy (LIBS), which involves firing a laser pulse at a sample to determine its composition from light spectra emitted via a spectrometer and a custom program, was chosen to be the basis of the portable system. Along with system development, results were analyzed via Partial Least Squares Regression (PLSR). The current analysis technique utilizes split-training and y-scaling to analyze spectra data and performs well for most samples