In this paper we combine Gaussian process regression and impedance control, to illicit robust, anthropomorphic, adaptive control of a powered ankle prosthesis. We learn the non-linear manifolds which guide how locomotion variables temporally evolve, and regress that surface over a velocity range to create a manifold. The joint set of manifolds, as well as the temporal evolution of the gait-cycle duration is what we term a locomotion envelope. Current powered prostheses have problems adapting across speeds. It is likely that humans rely upon a control strategy which is adaptable, can become more robust and accurate with more data and provides a nonparametric approach which allows the strategy to grow with the number of observations. We demonstrate such a strategy in this study and successfully simulate locomotion well beyond our training data. The method we propose is based on common physical features observed in numerous human subjects walking at different speeds. Based on the derived locomotion envelopes we show that ankle power increases monotonically with speed among all subjects. We demonstrate our methods in simulation and human experiments, on a powered ankle foot prosthesis to demonstrate the effectiveness of the method.

The use of human-interactive robots in industry and daily life has become more prevalent throughout society as more people are using collaborative, and assistive robots to accomplish a task. To demonstrate the utility and importance of assistive robots to middle school students, a unique educational platform called Neu-pulator (neurally-controlled manipulator) was designed and fabricated to introduce their application in improving the quality of life. This robotic manipulator consists of low-cost components, which reflect the characteristics of a human arm, and is actuated by signals from the students neuromuscular system. During summer 2016, a 5-day program introduced students to the engineering design process as they designed, programmed, manufactured, and tested the Neu-pulator robot. A series of surveys and group interviews were performed to understand how each students attitude and opinion towards different STEM-related topics evolved throughout the course, both quantitatively and qualitatively. We observed that the students confidence, attitude, and excitement towards STEM improved over the course of the week, especially when they could see the robot they developed in action. With the use of this unique educational platform, a bridge can be made from learning fundamental STEM concepts to real-world application of human interactive and assistive robots.

This paper describes the details of a theme-based and hands-on STEM learning program utilizing an underwater robot called GUPPIE. Glider for Underwater Problem-solving and Promotion of Interest in Engineering (GUPPIE) is an example of a robot with oceanographic and environmental monitoring application. GUPPIE helps students to learn about fundamentals of physics (buoyancy, gravity, drag and lift force), electronics (circuitry and power distribution), programming, building (using tools and assembly), and testing in a systematic way. In this work we analyse the effects of the hands-on activities with meaningful context on students' 1) confidence level; 2) attitude towards robotics; 3) and level of interest towards STEM careers. The survey results suggest that using robots with sensible real world applications improves young students' attitudes and interests towards robotics. Based on these results, introducing young students to topics that are not part of official school curriculum, such as programming, increases the excitement and confidence in early ages, especially for girls, and can result in pursuing STEM related subjects in higher education. Results also revealed tha.t girls are more interested in building while boys are more attracted to programming.

This paper, for the first time, describes the estimation of the time-varying impedance of the human ankle in the sagittal (SP) and frontal (FP) planes during the stance phase of walking. The result of this work is aimed to provide design parameters for the development of 2-DOF powered ankle-foot prostheses capable of mimicking the time-varying impedance of the human ankle. Sixteen axes of rotations combining different amounts of SP and FP rotations were studied. For each axis, positive and negative rotations were considered separately. Four unimpaired male subjects walked on an instrumented vibrating platform that applied combined torque perturbations in the SP and FP simultaneously, while the ankle angles and torques were recorded. Based on the recorded data, the ankle impedance was estimated with a time resolution of 20 ms from 7% to 93% of the stance length (SL). The ankle stiffness and damping showed great variability through the SL and across axes of rotation. The maximum stiffness was 4.7±0.5 Nm/rad/kg at 0.21 s of the SL when the ankle rotated at an axis 22.5° from the SP combining Dorsiflexion (D) and Inversion (I). The minimum stiffness was 1.4±0.6 Nm/rad/kg at 0.05 s of the SL at an axis 45° from the SP combining D and Eversion (E). The maximum damping was 0.09±0.02 Nms/rad/kg at 0.21 s of the SL combining D and I at an axis 25° from the SP. The minimum was 0.02±0.01 Nms/rad/kg at 0.05 s of the SL combining P and I at an axis 45° from the SP.

An underwater glider named ROUGHIE (Research Oriented Underwater Glider for Hands-on Investigative Engineering) is designed and manufactured to provide a test platform and framework for experimental underwater automation. This paper presents an efficient multi-level motion controller that can be used to enhance underwater glider control systems or easily modified for additional sensing, computing, or other requirements for advanced automation design testing. The ultimate goal is to have a fleet of modular and inexpensive test platforms for addressing the issues that currently limit the use of autonomous underwater vehicles (AUVs). Producing a low-cost vehicle with maneuvering capabilities and a straightforward expansion path will permit easy experimentation and testing of different approaches to improve underwater automation.