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Soft robots have the potential to interact with sensitive environments and perform complex tasks effectively. However, motion plans and trajectories for soft manipulators are challenging to calculate due to their deformable nature and nonlinear dynamics. This article introduces a fast real-time trajectory generation approach for soft robot manipulators, which creates dynamically-feasible motions for arbitrary kinematically-feasible paths of the robot's end effector. Our insight is that piecewise constant curvature (PCC) dynamics models of soft robots can be differentially flat, therefore control inputs can be calculated algebraically rather than through a nonlinear differential equation. We prove this flatness under certain conditions, with the curvatures of the robot as the flat outputs. Our two-step trajectory generation approach uses an inverse kinematics procedure to calculate a motion plan of robot curvatures per end-effector position, then, our flatness diffeomorphism generates corresponding control inputs that respect velocity. We validate our approach through simulations of our representative soft robot manipulator along three different trajectories, demonstrating a margin of 23x faster than real-time at a frequency of 100 Hz. This approach could allow fast verifiable replanning of soft robots' motions in safety-critical physical environments, crucial for deployment in the real world.

Estimating a soft robot's pose and applied forces, also called proprioception, is crucial for safe interaction of the robot with its environment. However, most solutions for soft robot proprioception use dedicated sensors, particularly for external forces, which introduce design trade-offs, rigidity, and risk of failure. This work presents an approach for pose estimation and contact detection for soft robots actuated by shape memory alloy (SMA) artificial muscles, using no dedicated force sensors. Our framework uses the unique material properties of SMAs to self-sense their internal stress, via offboard measurements of their electrical resistance and in-situ temperature readings, in an existing fully-soft limb design. We demonstrate that a simple polynomial regression model on these measurements is sufficient to predict the robot's pose, under no-contact conditions. Then, we show that if an additional measurement of the true pose is available (e.g. from an already-in-place bending sensor), it is possible to predict a binary contact/no-contact using multiple combinations of self-sensing signals. Our hardware tests verify our hypothesis via a contact detection test with a human operator. This proof-of-concept validates that self-sensing signals in soft SMA-actuated soft robots can be used for proprioception and contact detection, and suggests a direction for integrating proprioception into soft robots without design compromises. Future work could employ machine learning for enhanced accuracy., Comment: 6 pages, 7 figures

Soft robots have immense potential given their inherent safety and adaptability, but challenges in soft actuator forces and design constraints have limited scaling up soft robots to larger sizes. Electrothermal shape memory alloy (SMA) artificial muscles have the potential to create these large forces and high displacements, but consistently using these muscles under a well-defined model, in-situ in a soft robot, remains an open challenge. This article provides a system for maintaining the highest-possible consistent SMA forces, over long lifetimes, by combining a fatigue testing protocol with a supervisory control system for the muscles' internal temperature state. We propose a design of a soft limb with swap-able SMA muscles, and deploy the limb in a blocked-force test to quantify the relationship between the measured maximum force at different temperatures over different lifetimes. Then, by applying an invariance-based control system to maintain temperatures under our long-life limit, we demonstrate consistent high forces in a practical task over hundreds of cycles. The method we developed allows for practical implementation of SMAs in soft robots through characterizing and controlling their behavior in-situ, and provides a method to impose limits that maximize their consistent, repeatable behavior., Comment: 8 pages, 8 figures, accepted by 2024 IEEE International Conference on Soft Robotics (RoboSoft)

Legged robots constructed from soft materials are commonly claimed to demonstrate safer, more robust environmental interactions than their rigid counterparts. However, this motivating feature of soft robots requires more rigorous development for comparison to rigid locomotion. This article presents a soft legged robot platform, Horton, and a feedback control system with safety guarantees on some aspects of its operation. The robot is constructed using a series of soft limbs, actuated by thermal shape memory alloy (SMA) wire muscles, with sensors for its position and its actuator temperatures. A supervisory control scheme maintains safe actuator states during the operation of a separate controller for the robot's pose. Experiments demonstrate that Horton can lift its leg and maintain a balancing stance, a precursor to locomotion. The supervisor is verified in hardware via a human interaction test during balancing, keeping all SMA muscles below a temperature threshold. This work represents the first demonstration of a safety-verified feedback system on any soft legged robot., Comment: 8 pages, 4 figures

"Imparting Wisdom: HBCU Lessons for K-12 Education" details historically black colleges and universities' (HBCUs) longstanding efforts to provide quality educational experiences for their students and how their success may be translated in K-12 schools. This brief uplifts research-based HBCU best practices, practical recommendations and insights from HBCU leaders, with the goal of promoting mutually beneficial alliances between the K-12 and higher education communities. The outlined lessons in the report rest on the following best practices that HBCUs employ: (1) cultivating nurturing support systems; (2) leveraging African American culture and identity; and (3) setting high expectations. Each best practice also details corresponding lessons for the K-12 space. These HBCU "best practices" can serve as effective models for K-12 schools, districts and charter management organizations (CMOs) in improving the educational outcomes of students from disadvantaged backgrounds.

This report is the third in a series that probes community reactions to K-12 education; its two predecessors, "Lift Every Voice and Lead: African American Leaders' Perceptions of K-12 Education Reform" (see ED588631), and "Done to Us, Not with Us: African American Parent Perceptions of K-12 Education" (see ED573649), addressed the roles that should be played by parents and community leaders. The role to be played by youth is just as important. They are, after all, the stakeholders whose response to reform will determine if it succeeds or fails. Of the three groups, they are the only one with firsthand knowledge of what happens in the classroom. And, all too often, they do not have a seat at the table during reform discussions. This study begins to remedy that omission. The findings indicate that African American youth want to be heard, and they offer meaningful commentary on the educational environment and the structural issues that may impede their success. African American youth consider education a key factor in achieving their life goals and overwhelmingly want a college degree; yet, like parents and leaders, many students, especially those from low-income backgrounds, often lack the information needed to successfully navigate the educational landscape. This information deficit often creates barriers to college entry and can have enduring effects on students and communities. This report summarizes the perceptions of African American youth on K-12 education and provides actionable recommendations for improving the educational trajectories of all students.

This brief encourages leaders to utilize their influence to help alleviate the long-standing achievement gaps in the education system, because when students flourish, entire communities can flourish as well. The authors want to ensure that grasstops are intentional in their advocacy for black students. The "Lift Every Voice and Lead Toolkit" provides tangible tips, strategies, talking points and resources to help grasstops who are serious about using their influence to make transformational change for all youth. [For the first report in this series, "Done to Us, Not with Us: African American Parent Perceptions of K-12 Education," see ED573649. For the second report, "Lift Every Voice and Lead: African American Leaders' Perceptions of K-12 Education Reform," see ED588631.]

UNCF conducted this study to shed light on African American grasstops' perspectives toward education reform and how they work to develop community-centered strategies to address disparities in schools. One narrative about the lack of engagement by local grasstops in education reform is that they do not care or are not informed about the topic. Such perceptions of apathy may not bode well for collaboration with communities or schools and could thwart progress for reform efforts. As such, UNCF wanted to investigate this phenomenon in greater detail. This study explored three areas of interest, which are followed by their guiding research questions: (1) Problems affecting people within the community: What are the serious issues affecting people in your city and community? What should be the highest priority in improving your community? (2) Perspectives on education: How are public schools doing in preparing African American students to attend and graduate from college? What are the top priorities for improving the educational landscape for African American students? and (3) Barriers to student success: How well are African American leaders doing in responding to the educational crisis facing African American students? What most affects the quality of education in your community? The key results suggest that there is, in fact, fertile ground for collaboration between parents and grasstops as the leaders expressed a strong sense of optimism in their ability to advance educational progress for students. Findings range from perceptions of the state of education for black youth to evaluations of grasstops' role in improving educational opportunities. The results reveal that African American grasstops are informed about various issues in education and would like to be further engaged in education reform work. "Lift Every Voice and Lead" is the second report in a three-part series on African American perceptions of K-12 education. [For the first report in this series, "Done to Us, Not with Us: African American Parent Perceptions of K-12 Education," see ED573649.]

"Building Better Narratives in Black Education" fundamentally changes the narrative and face of education reform to meaningfully include Black voices, leaders and initiatives that truly have equity and Black student success at the core. This is imperative as there is an education crisis for Black students in the United States. Recent National Assessment of Educational Progress (NAEP) results indicate that only seven percent of Black students performed at or above proficient on the 12th grade math exam in 2015, compared with 32 percent of White students. African American students are less likely to meet ACT college readiness benchmarks than any other racial group and often lag behind on various indicators on the primary and secondary levels. However, far too often the narrative has stopped there. While it is important to deconstruct and analyze inequities in the educational system, we have to move from solely deficit-based narratives to decisions to strengthen policies and conversations that fundamentally change the state of education for African American students. It's time to build a better, more actionable narrative that represents the promise of education to drive equity. UNCF, Education Post, and the National Urban League each collected data on African Americans' perspective on significant K-12 education issues, and this report synthesizes salient themes from these various data. Grounded in the lived experiences of the African American community, "Building Better Narratives in Black Education" provides tangible approaches to fundamentally shift the narrative concerning Black educational reform in order to better engage communities and reformers around an equitable K-12 education system. Sections about the contributors and the methodology are appended.