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  1. Mechatronics and Robotics Engineering (MRE) is a growing engineering discipline focused on the creation of smart and autonomous systems and processes in an integrated and interdisciplinary fashion towards improving the quality of human lives. Despite the growing need for MRE professionals and increasing numbers of undergraduate and graduate degree programs, this field does not yet enjoy recognition as a distinct and identifiable discipline. A distinct and identifiable engineering discipline must address four questions: 1) What is the body of knowledge that practitioners must master? 2) What skills must practitioners demonstrate? 3) What are the ways of thinking that permeate the discipline? 4) How do practitioners define and distinguish the discipline? Within the MRE community, there is disagreement over how these questions are addressed, and hence, whether and how to define a unified “mechatronics and robotics engineering” discipline or to differentiate “mechatronics engineering” from “robotics engineering”. Four groups of stakeholders were identified: prospective students, current students, educators, and industry professionals. An online survey with common sections on definitions of “mechatronics engineering” and “robotics engineering” and stakeholder-specific questions about differentiators was distributed to stakeholders via email invitation. Quantitative data analysis was used to code and categorize responses. Preliminary data analysis results for categories and codes are presented. 
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  2. Robustness, compactness, and portability of tensegrity robots make them suitable candidates for locomotion on unknown terrains. Despite these advantages, challenges remain relating to simplicity of fabrication and locomotion. The paper introduces a design solution for fabricating tensegrity robots of varying morphologies with modular components created using rapid prototyping techniques, including 3D printing and laser-cutting. % It explores different robot morphologies that attempt to balance structural complexity while facilitating smooth locomotion. The techniques are utilized to fabricate simple tensegrity structures, followed by tensegrity robots in icosahedron and half-circle arc morphologies. Locomotion strategies for such robots involve altering of the position of center-of-mass to induce `tip-over'. Furthermore, the design of curved links of tensegrity mechanisms facilitates continuous change in the point of contact (along the curve) as compared to piece-wise continuous in the traditional straight links (point contact) which induces impulse reaction forces during locomotion. The resulting two tensegrity robots - six-straight strut icosahedron and two half-circle arc morphology - achieve locomotion through internal mass-shifting utilizing the presented modular mass-shifting mechanism. The curve-link tensegrity robot demonstrates smooth locomotion along with folding-unfolding capability. 
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  3. Patients suffering from medical conditions resulting in hand impairment experience difficulty in performing simple daily tasks, like getting dressed or using a pencil, resulting in a poorer quality of life. Rehabilitation attempts to help such individuals regain a sense of control and normalcy. In this context, recent advances in robotics have manifested in multiple designs of hand exoskeletons and exosuit gloves for assistance and rehabilitation. These designs are typically actuated using pneumatic, shape memory alloys and motor-tendon actuators. The proposed Motor Tendon Actuated Exosuit Glove (MTAEG) with an open palm is a soft material glove capable of both flexion and extension of all four fingers of the human hand. Its minimally invasive design maintains an open palm to facilitate haptic and tactile interaction with the environment. The MTAEG achieves flexion-extension motion with joint angles of 45° at the metacarpal joint which is 57% of the desired motion; 90° at the proximal interphalangeal joint which is 100% of the desired motion; and 50° at the distal interphalangeal joint which is 96% of the desired motion. The paper discusses the challenges in achieving the desired motion without the ability to directly model human tendons, and the inability to actuate joints individually. 
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  4. Abstract

    Degenerative disc disease (DDD) is the leading cause of low back pain and radiating leg pain. DDD is commonly treated surgically using spinal fusion techniques, but in many cases failure occurs due to insufficient immobilization of the vertebrae during fusion. The fabrication and demonstration of a 3D‐printed semi‐crystalline liquid crystal elastomer (LCE) spinal fusion cage that addresses these challenges in particular subsidence are described. During implantation of the fusion cage, the LCE is rubbery and capable of deforming around and conforming to delicate anatomy. In the hours following implantation, the device crystallizes into a rigid, structural material with the modulus increasing tenfold from 8 to 80 MPa. In the crystalline regime, a 3D‐printed prototype device is capable of enduring 1 million cycles of physiologic compressive loading with minimal creep‐induced ratcheting. Effects of LCE molecular architecture on the rate and magnitude of modulus increase, material processability, and mechanical properties are explored. This fundamental characterization informs a proof‐of‐concept device—the first bulk 3D printed LCE demonstrated to date. Moreover, the novel deployment strategy represents an exciting new paradigm of spinal fusion cages, which addresses real clinical challenges in expandable interbody fusion cages.

     
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