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Articles 1 - 6 of 6
Full-Text Articles in Social and Behavioral Sciences
Predicting The Influence Of Hip And Lumbar Flexibility On Lifting Motions Using Optimal Control, Manish Sreenivasa, Matthew Millard, Idsart Kingma, Jaap H. Van Dieen, Katja Mombaur
Predicting The Influence Of Hip And Lumbar Flexibility On Lifting Motions Using Optimal Control, Manish Sreenivasa, Matthew Millard, Idsart Kingma, Jaap H. Van Dieen, Katja Mombaur
Faculty of Engineering and Information Sciences - Papers: Part B
Computational models of the human body coupled with optimization can be used to predict the influence of variables that cannot be experimentally manipulated. Here, we present a study that predicts the motion of the human body while lifting a box, as a function of flexibility of the hip and lumbar joints in the sagittal plane. We modeled the human body in the sagittal plane with joints actuated by pairs of agonist-antagonist muscle torque generators, and a passive hamstring muscle. The characteristics of a stiff, average and flexible person were represented by co-varying the lumbar range-of-motion, lumbar passive extensor-torque and the …
Optimal Control Based Stiffness Identification Of An Ankle-Foot Orthosis Using A Predictive Walking Model, Manish Sreenivasa, Matthew Millard, Martin Felis, Katja Mombaur, Sebastian I. Wolf
Optimal Control Based Stiffness Identification Of An Ankle-Foot Orthosis Using A Predictive Walking Model, Manish Sreenivasa, Matthew Millard, Martin Felis, Katja Mombaur, Sebastian I. Wolf
Faculty of Engineering and Information Sciences - Papers: Part B
Predicting the movements, ground reaction forces and neuromuscular activity during gait can be a valuable asset to the clinical rehabilitation community, both to understand pathology, as well as to plan effective intervention. In this work we use an optimal control method to generate predictive simulations of pathological gait in the sagittal plane. We construct a patient-specific model corresponding to a 7-year old child with gait abnormalities and identify the optimal spring characteristics of an ankle-foot orthosis that minimizes muscle effort. Our simulations include the computation of foot-ground reaction forces, as well as the neuromuscular dynamics using computationally efficient muscle torque …
Predicting The Motions And Forces Of Wearable Robotic Systems Using Optimal Control, Matthew Millard, Manish Sreenivasa, Katja Mombaur
Predicting The Motions And Forces Of Wearable Robotic Systems Using Optimal Control, Matthew Millard, Manish Sreenivasa, Katja Mombaur
Faculty of Engineering and Information Sciences - Papers: Part B
Wearable robotic systems are being developed to prevent injury to the low back. Designing a wearable robotic system is challenging because it is difficult to predict how the exoskeleton will affect the movement of the wearer. To aid the design of exoskeletons, we formulate and numerically solve an optimal control problem (OCP) to predict the movements and forces of a person as they lift a 15 kg box from the ground both without (human-only OCP) and with (with-exo OCP) the aid of an exoskeleton. We model the human body as a sagittal-plane multibody system that is actuated by agonist and …
Optimizing Wearable Assistive Devices With Neuromuscular Models And Optimal Control, Manish Sreenivasa, Matthew Millard, Paul Manns, Katja Mombaur
Optimizing Wearable Assistive Devices With Neuromuscular Models And Optimal Control, Manish Sreenivasa, Matthew Millard, Paul Manns, Katja Mombaur
Faculty of Engineering and Information Sciences - Papers: Part B
The coupling of human movement dynamics with the function and design of wearable assistive devices is vital to better understand the interaction between the two. Advanced neuromuscular models and optimal control formulations provide the possibility to study and improve this interaction. In addition, optimal control can also be used to generate predictive simulations that generate novel movements for the human model under varying optimization criterion.
Hrp-2 Plays The Yoyo: From Human To Humanoid Yoyo Playing Using Optimal Control, Katja Mombaur, Manish Sreenivasa
Hrp-2 Plays The Yoyo: From Human To Humanoid Yoyo Playing Using Optimal Control, Katja Mombaur, Manish Sreenivasa
Faculty of Engineering and Information Sciences - Papers: Part B
Yoyo playing may seem easy for a human, but it is a challenging problem for a humanoid robot. This paper presents an approach to generate yoyo motions for the humanoid robot, HRP-2, based on motion recorded from human yoyo playing, dynamical models and numerical optimal control techniques. We recorded vertical yoyo playing of 4 subjects measuring yoyo height and rotation angle as well as the corresponding hand motions. A detailed multi-phase yoyo model with impact collisions and control patterns of human yoyo playing were identified from these measurements. Based on this knowledge, reliable yoyo motions within the feasibility ranges of …
Inverse Optimal Control As A Tool To Understand Human Yoyo Playing, Katja Mombaur, Manish Sreenivasa
Inverse Optimal Control As A Tool To Understand Human Yoyo Playing, Katja Mombaur, Manish Sreenivasa
Faculty of Engineering and Information Sciences - Papers: Part B
This paper presents an inverse optimal control approach to identify objective functions of human motion from motion capture measurements. We apply it to analyze human yoyo playing. Yoyo playing may seem easy to us to learn but it is a challenging problem from a mechanical point of view involving a hybrid dynamics model. We recorded vertical yoyo playing of humans measuring yoyo height and rotation angle as well as the corresponding hand motions. Results of inverse optimal control are presented showing a mixed criterion of cycle time and terms depending on yoyo and hand acceleration and velocity.