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Tank farm workers involved in nuclear cleanup activities perform physically demanding tasks, typically while wearing heavy personal protective equipment (PPE). Exoskeleton devices have the potential to bring considerable benefit to this industry but have not been thoroughly studied in the context of nuclear cleanup. In this paper, we examine the performance of exoskeletons during a series of tasks emulating jobs performed on tank farms while participants wore PPE commonly deployed by tank farm workers. The goal of this study was to evaluate the effects of commercially available lower-body exoskeletons on a user’s gait kinematics and user perceptions. Three participants each tested three lower-body exoskeletons in a 70-min protocol consisting of level treadmill walking, incline treadmill walking, weighted treadmill walking, a weight lifting session, and a hand tool dexterity task. Results were compared to a no exoskeleton baseline condition and evaluated as individual case studies. The three participants showed a wide spectrum of user preferences and adaptations toward the devices. Individual case studies revealed that some users quickly adapted to select devices for certain tasks while others remained hesitant to use the devices. Temporal effects on gait change and perception were also observed for select participants in device usage over the course of the device session. Device benefit varied between tasks, but no conclusive aggregate trends were observed across devices for all tasks. Evidence suggests that device benefits observed for specific tasks may have been overshadowed by the wide array of tasks used in the protocol. 

Open Source Hardware allows users to share, customize, and improve designs, thus enabling technological advancement through communities of practice. We propose open source hardware for educational haptics that permits researchers, educators, and students to share designs arising from their different perspectives, with the potential to expand educational applications. In this paper we present a family of open source kinesthetic haptic devices that build upon the design of a previous educational haptic device, Hapkit 3.0. First, we discuss methods for Hapkit personalization and customization that can be achieved by K-12 students and educators. Next, we describe two kinesthetic haptic device designs that evolved from the original Hapkit 3.0. One uses two standard Hapkits with additional components to form a Pantograph mechanism, and the other uses customized Hapkit elements along with a novel kinematic design to form a serial mechanism. These designs are modular; after building two Hapkits, a user acquires a small number of additional parts to transform them into a two-degree-of-freedom device. The Pantograph mechanism was used in an undergraduate class to teach robotics and haptics to both engineering and nonengineering students. Open source designs for all devices as well as tutorials for customization are available at http://hapkit.stanford.edu.