We present a personal mobility device for lower-body impaired users through a light-weighted exoskeleton on wheels. On its core, a novel passive exoskeleton provides postural transition leveraging natural body postures with support to the trunk on sit-to-stand and stand-to-sit (STS) transitions by a single gas spring as an energy storage unit. We propose a direction-dependent coupling of knees and hip joints through a double-pulley wire system, transferring energy from the torso motion towards balancing the moment load at the knee joint actuator. Herewith, the exoskeleton maximizes energy transfer and the naturalness of the user's movement. We introduce an embodied user interface for hands-free navigation through a torso pressure sensing with minimal trunk rotations, resulting on average $19^{\circ} \pm 13^{\circ}$ on six unimpaired users. We evaluated the design for STS assistance on 11 unimpaired users observing motions and muscle activity during the transitions. Results comparing assisted and unassisted STS transitions validated a significant reduction (up to $68\%$ $p<0.01$) at the involved muscle groups. Moreover, we showed it feasible through natural torso leaning movements of $+12^{\circ}\pm 6.5^{\circ}$ and $- 13.7^{\circ} \pm 6.1^{\circ}$ for standing and sitting, respectively. Passive postural transition assistance warrants further work on increasing its applicability and broadening the user population.
École Polytechnique de Montréal（蒙特利尔理工学院）；Marie Enfant Rehabilitation Centre（玛丽儿童康复中心）
Low back pain is one of the most common musculoskeletal disorder. To reduce its incidences, some back exoskeletons have been designed and already commercialized. However, there is a gap between the phases of device and testing on subjects. In fact, the main unsolved problem is the lack of realistic simulation of human-device interaction. Consequently, the objective of this paper is to design a 3D multibody model of the human body that includes the full thoracic and lumbar spine combined with a low back exoskeleton, enabling to analyze the interactions between them. The results highlight that t…
ETH Zurich（苏黎世联邦理工学院）；Balgrist University Hospital（巴尔格里斯特大学医院）；University of Zurich（苏黎世大学）
Spinal cord injuries frequently impair the ability to walk. Powered lower limb exoskeletons offer a promising solution to restore walking ability. However, they are currently restricted to even ground. We hypothesized that compliant exoskeleton knees could decrease required effort to maneuver on uneven terrain, and increase gait velocity and stability. We describe a case study of a motor-complete spinal cord injury user (AIS A, Th12) walking with a powered exoskeleton on even and uneven ground over multiple sessions after extensive training. Measurements with compliant or rigid exoskeleton kne…
The City University of New York, City College（纽约市立大学城市学院）
Pediatric exoskeletons offer great promise to increase mobility for children with crouch gait caused by cerebral palsy. A lightweight, compliant and user-specific actuator is critical for maximizing the benefits of an exoskeleton to users. To date, pediatric exoskeletons generally use the same actuators as adult exoskeletons, which are heavy and resistive to natural movement. There is yet no easy way for robotic exoskeletons to accommodate the changes in design requirements that occur as a child ages. We developed a lightweight (1.65 kg unilateral mass) and compliant pediatric knee exoskeleton…
The City University of New York, City College（纽约城市大学城市学院）；Argonne National Laboratory（阿贡国家实验室）
This paper presents design and control innovations of wearable robots that tackle two barriers to widespread adoption of powered exoskeletons, namely restriction of human movement and versatile control of wearable co-robot systems. First, the proposed quasi-direct drive actuation comprising of our customized high torque density motors and low ratio transmission mechanism significantly reduces the mass of the robot and produces high backdrivability. Second, we derive a biomechanics model-based control that generates biological torque profile for versatile control of both squat and stoop lifting…
University of Michigan（密歇根大学）；Shanghai Jiao Tong University（上海交通大学）
Task-dependent controllers widely used in exoskeletons track predefined trajectories, which overly constrain the volitional motion of individuals with remnant voluntary mobility. Energy shaping, on the other hand, provides task-invariant assistance by altering the human body's dynamic characteristics in the closed loop. While human-exoskeleton systems are often modeled using Euler-Lagrange equations, in our previous work we modeled the system as a port-controlled-Hamiltonian system, and a task-invariant controller was designed for a knee-ankle exoskeleton using interconnection-damping assignme…
New Jersey Institute of Technology（新泽西理工学院）；CFD Research Corporation（CFD研究公司）
In this paper, we present an integrated human-in-the-loop simulation paradigm for the design and evaluation of a lower extremity exoskeleton that is elastically strapped onto human lower limbs. The exoskeleton has 3 rotational DOFs on each side and weighs 23kg. Two torque compensation controllers of the exoskeleton are introduced, aiming to minimize interference and maximize assistance to human motions, respectively. Their effects on the wearer's biomechanical loadings are studied with a running motion and predicted ground reaction forces. It is found that the added weight of the passive exosk…
Force Myography based Torque Estimation in Human Knee and Ankle Joints
High Performance Humanoid Technologies Lab, Institute for Anthropomatics and Robotics, Karlsruhe Institute of Technology (KIT), Germany（高性能人形机器人实验室，人机学与机器人研究所，卡尔斯鲁厄理工学院（KIT））；BioMotion Center, Institute of Sports and Sports Sciences, Karlsruhe Institute of Technology (KIT), Germany（生物运动中心，体育与体育科学研究所，卡尔斯鲁厄理工学院（KIT））
University of Tehran（德黑兰大学）；Harvard Medical School（哈佛医学院）；Tehran University of Medical Sciences（德黑兰医科大学）；Yerevan State Medical University（埃里温国立医科大学）；University of Texas at Dallas（德克萨斯大学达拉斯分校）
Stationary robotic trainers are lower limb rehab robots which often incorporate an exoskeleton attached to a stationary base. The issue observed in the stationery trainers for simultaneous knee and ankle-foot complex joints is that they restrict the natural motion of ankle-foot in the rehab trainings due to the insufficient Degrees of Freedom (DOFs) of these trainers. A new stationary knee-ankle-foot rehab robot with all necessary DOFs is developed here. A typical rehab training is first implemented in simulation, and then tested on a healthy subject. Results show that the proposed system func…
Institute for Human and Machine Cognition（人类与机器认知研究所）
Exoskeletons are a promising technology that enables individuals with mobility limitations to walk again. As the 2016 Cybathlon illustrated, however, the community has a considerable way to go before exoskeletons have the necessary capabilities to be incorporated into daily life. While most exoskeletons power only hip and knee flexion, Team Institute for Human and Machine Cognition (IHMC) presents a new exoskeleton, Mina v2, which includes a powered ankle dorsi/plantar flexion. As our entry to the 2016 Cybathlon Powered Exoskeleton Competition, Mina v2's performance allowed us to explore the e…
Imperial College London（帝国理工学院）；University of Paris-Est Créteil（巴黎东克雷泰伊大学）；McLaren Applied（迈凯伦应用公司）
Loss of mobility or balance resulting from neural trauma is a critical consideration in public health. Robotic exoskeletons hold great potential for rehabilitation and assisted movement, yet optimal assist-as-needed (AAN) control remains unresolved given pathological variance among patients. We introduce a model predictive control (MPC) architecture for lower limb exoskeletons centred around a fuzzy logic algorithm (FLA) identifying modes of assistance based on human involvement. Assistance modes are: 1) passive for human relaxed and robot dominant, 2) active-assist for human cooperation with …
The Impact of Gait Pattern Personalization on the Perception of Rigid Robotic Guidance: A Pilot User Experience Evaluation
Cognitive Robotics Department, Delft University of Technology（代尔夫特理工大学认知机器人学系）；Department of Rehabilitation Medicine, Erasmus Medical Centre（伊拉斯姆斯医学中心康复医学系）；Department of Biomechanical Engineering, Delft University of Technology（代尔夫特理工大学生物力学工程系）；Institute of Automatic Control, RWTH Aachen University（亚琛工业大学自动控制研究所）；Department of Mechanical Engineering, FUM Center of Advanced Rehabilitation and Robotics Research (FUM CARE), Ferdowsi University of Mashhad（菲尔多西大学机械工程系先进康复与机器人研究中心）；Walker Department of Mechanical Engineering, University of Texas at Austin（德克萨斯大学奥斯汀分校沃克机械工程系）
Wearable robots are limited by their actuators performances because they must bear the weight of their own power system and energy source. This paper explores the idea of leveraging hybrid modes to meet multiple operating points with a lightweight and efficient system by using hydraulic valves to dynamically reconfigure the connections of a hydrostatic actuator. The analyzed opportunities consist in 1) switching between a highly geared power source or a fast power source, 2) dynamically connecting an energy accumulator and 3) using a locking mechanism for holding. Based on a knee exoskeleton c…
Force Sensing for Wearable Human-Robot Interfaces via Fluidic Innervation
Rehabilitation Medicine Department, National Institutes of Health (NIH) Clinical Center（国家卫生研究院（NIH）临床中心康复医学部门）；Department of Electrical and Computer Engineering, University of Texas at Austin（德克萨斯大学奥斯汀分校电气与计算机工程系）
