Improving Human-Exoskeleton Fluency Through an Investigation of Dynamic Control Parameters

可穿戴机器人外骨骼有可能通过提供辅助力量来减少工作场所的伤害，从而减少人类工人的身体负荷。本计画的目的是研究踝关节外骨骼在与使用者互动时的可用性与使用者心理舒适度。该设备将被编程为人们行走和改变行走速度时提供动态支持。长期目标是开发推断和预测其用户意图的技术，并使用该信息来调整外骨骼的行为，以最大限度地提高用户对外骨骼系统和人类-外骨骼“流畅性”的信任，该“流畅性”被定义为人类-技术团队内的动作的同步啮合。 人-外骨骼流畅性来自人与外骨骼之间的共适应，由人在使用系统时选择的运动策略以及基于人的控制策略中的更新驱动。该项目的目标是研究辅助力驱动的时间和存在的不确定性如何影响人类外骨骼流畅性和人类对外骨骼系统的信任。这项研究将对军事应用和工业应用产生影响，在军事应用中，肌肉骨骼过度使用损伤的发生率很高，威胁到军事准备，在工业应用中，肌肉拉伤、扭伤和撕裂导致约三分之一的工作日损失。 通过将用户意图、人类信任和人类-外骨骼流畅性模型与Defy仿生靴子相结合，该项目将推进NSF的使命，即通过探索外骨骼步态辅助背景下人类行为、运动控制和机器操作的基本关系，促进科学进步和促进国民健康。 该项目通过外展、课程开发和导师制支持K-5、本科和研究生教育。作为开发与人类用户共同适应的预期辅助外骨骼控制器的第一步，拟议研究的具体目标是测试人类信任和人类外骨骼流畅性受以下因素影响的假设：（1）辅助力过渡时间和（2）早期，晚期，或者在步态周期内错过致动。 该项目有三个目标。第一个目的是评估辅助力过渡时间的变化对人类外骨骼流畅性的影响。 第二个评估辅助力驱动的时间和存在的不确定性如何影响人类的表现和系统的信任。第三个目标是开发一个自适应控制器，旨在不断提高实时流畅性。研究团队使用市售的Defy仿生靴子和自定义控制算法进行假设评估。本研究将在CAREN虚拟现实环境中，在允许自我起搏的分离式带仪表跑步机上进行。受试者将执行速度变化的任务，同时也执行双重任务，并回答旨在探索情境意识的问题。分析了人-外骨骼流畅性和信任度的新度量。这项工作可能会导致可穿戴外骨骼系统的适应性，能力和可用性的显着改善，以提高人类在工业和军事应用中的表现。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Wearable robotic exoskeletons have potential to reduce workplace injuries by providing assistive forces that decrease the physical loads human workers experience. The goal of this project is to study the usability and user psychological comfort of an ankle exoskeleton during its interactions with its user. The device will be programmed to provide dynamic support as people walk and change walking speeds. The long term goals are to develop technology that infers and anticipates its user's intent, and to use that information to adapt the exoskeleton's behavior to maximize the user's trust in the exoskeletal system and the human-exoskeletal "fluency", defined as the synchronized meshing of actions within the human-technology team. Human-exoskeleton fluency results from the co-adaptation between the human and exoskeleton, driven by the motor strategies selected by the human when using the system and by the updates in the control policy based on the human. The goal of this project is to examine how uncertainty in the timing and presence of assistive force actuations impacts human-exoskeleton fluency and human trust in the exoskeletal system. This research will be impactful both for military applications, where high rates of musculoskeletal overuse injury threaten military readiness, and for industrial applications, where muscle strains, sprains, and tears cause about one third of the reported cases of lost work days. By integrating models of user intent, human trust, and human-exoskeleton fluency with the Dephy Bionic Boot, this project will advance the NSF mission to promote the progress of science and advance national health by exploring fundamental relationships human behavior, motor control, and machine manipulation within the context of exoskeletal gait assistance. The project supports K-5, undergraduate and graduate education through outreach, curriculum development, and mentorship.As a first step towards developing an anticipatory assistive exoskeleton controller that co-adapts with its human user, the specific objective of the proposed research is to test the hypotheses that human trust and human-exoskeleton fluency are affected by (1) assistive force transition timing and (2) early, late, or missed actuations within the gait cycle. This project has three aims. The first seeks to evaluate the effect of variations in assistive force transition timing on human-exoskeleton fluency. The second evaluates how uncertainty in the timing and presence of assistive force actuations impacts human performance and system trust. The third aim develops a co-adaptive controller that seeks to continuously increase fluency in real-time. The research team uses the commercially available Dephy Bionic Boot with custom control algorithms to permit hypothesis evaluation. The study will be performed within a CAREN virtual reality environment on a split-belt, instrumented treadmill that permits self-pacing. Subjects will perform speed changing tasks while also performing dual tasks and responding to questions designed to probe situation awareness. New measures of human-exoskeleton fluency and trust are analyzed. This work could lead to significant improvements in the adaptability, capability, and usability of wearable exoskeletal systems for human performance enhancement in industrial and military applications.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.