Utilising an advanced technology of people tracking in vibration serviceability application

This is the author accepted manuscript. The final version is available from Springer via the DOI in this recordEVACES 2017 - 7th International Conference on Experimental Vibration Analysis for Civil Engineering Structures, San Diego, USA, 12-14 July 2017There is a continuous development in the facilities used for experimental measurements of human-induced vibrations due to walking of people in real-life structures. These facilities can be classified into three categories: 1. systems used to measure walking forces, 2. systems used to measure structural dynamic properties and vibration responses and 3. equipment required to locate the position of people within the structure. In recent years, state-of-the-art technologies have enabled both direct and indirect measurement of walking forces and vibration responses with improved accuracy. However, determining people’s position on the structure they occupy and dynamically excite is still a challenge, despite its importance. This is due to the limitations and lack of accuracy of existing systems used for this purpose. This paper presents an advanced system based on the Ultra-WideBand (UWB) technology to track the position of multiple people within civil engineering structures. It is demonstrated that this system has the capability of providing measurements of people’s positions in real-time, with around 50 cm accuracy, using wearable compact tags. In addition to the accuracy, the simple setting up and capability to track people’s positions in different types of structures are advantages over other types of body location tracking systems. Incorporating the above mentioned systems to measure simultaneously walking-induced forces, realistic time-varying locations of these forces and the corresponding time-varying vibration responses has created an unprecedented opportunity to boost considerably research pertinent to human-induced vibration. This will be based on invaluable but, until now, difficult to conduct real-life simultaneous measurements of these three key time-varying walkingforce parameters.The authors are grateful for the College of Engineering, Mathematics and Physical Sciences in the University of Exeter for the financial support they provided for the first author and his PhD program. The authors would also like to acknowledge the financial support provided by the UK Engineering and Physical Sciences Research Council (EPSRC) for grant reference EP/K03877X/1 ('Modelling complex and partially identified engineering problems- Application to the individualised multiscale simulation of the musculoskeletal system')

Muscle Synergies Facilitate Computational Prediction of Subject-Specific Walking Motions.

Researchers have explored a variety of neurorehabilitation approaches to restore normal walking function following a stroke. However, there is currently no objective means for prescribing and implementing treatments that are likely to maximize recovery of walking function for any particular patient. As a first step toward optimizing neurorehabilitation effectiveness, this study develops and evaluates a patient-specific synergy-controlled neuromusculoskeletal simulation framework that can predict walking motions for an individual post-stroke. The main question we addressed was whether driving a subject-specific neuromusculoskeletal model with muscle synergy controls (5 per leg) facilitates generation of accurate walking predictions compared to a model driven by muscle activation controls (35 per leg) or joint torque controls (5 per leg). To explore this question, we developed a subject-specific neuromusculoskeletal model of a single high-functioning hemiparetic subject using instrumented treadmill walking data collected at the subject's self-selected speed of 0.5 m/s. The model included subject-specific representations of lower-body kinematic structure, foot-ground contact behavior, electromyography-driven muscle force generation, and neural control limitations and remaining capabilities. Using direct collocation optimal control and the subject-specific model, we evaluated the ability of the three control approaches to predict the subject's walking kinematics and kinetics at two speeds (0.5 and 0.8 m/s) for which experimental data were available from the subject. We also evaluated whether synergy controls could predict a physically realistic gait period at one speed (1.1 m/s) for which no experimental data were available. All three control approaches predicted the subject's walking kinematics and kinetics (including ground reaction forces) well for the model calibration speed of 0.5 m/s. However, only activation and synergy controls could predict the subject's walking kinematics and kinetics well for the faster non-calibration speed of 0.8 m/s, with synergy controls predicting the new gait period the most accurately. When used to predict how the subject would walk at 1.1 m/s, synergy controls predicted a gait period close to that estimated from the linear relationship between gait speed and stride length. These findings suggest that our neuromusculoskeletal simulation framework may be able to bridge the gap between patient-specific muscle synergy information and resulting functional capabilities and limitations

Dynamic walking with Dribbel

This paper describes the design and construction of Dribbel, a passivity-based walking robot. Dribbel has been designed and built at the Control Engineering group of the University of Twente. This paper focuses on the practical side: the design approach, construction, electronics, and software design. After a short introduction of dynamic walking, the design process, starting with simulation, is discussed

Feedback Control of an Exoskeleton for Paraplegics: Toward Robustly Stable Hands-free Dynamic Walking

This manuscript presents control of a high-DOF fully actuated lower-limb exoskeleton for paraplegic individuals. The key novelty is the ability for the user to walk without the use of crutches or other external means of stabilization. We harness the power of modern optimization techniques and supervised machine learning to develop a smooth feedback control policy that provides robust velocity regulation and perturbation rejection. Preliminary evaluation of the stability and robustness of the proposed approach is demonstrated through the Gazebo simulation environment. In addition, preliminary experimental results with (complete) paraplegic individuals are included for the previous version of the controller.Comment: Submitted to IEEE Control System Magazine. This version addresses reviewers' concerns about the robustness of the algorithm and the motivation for using such exoskeleton

In silico case studies of compliant robots: AMARSI deliverable 3.3

In the deliverable 3.2 we presented how the morphological computing ap- proach can significantly facilitate the control strategy in several scenarios, e.g. quadruped locomotion, bipedal locomotion and reaching. In particular, the Kitty experimental platform is an example of the use of morphological computation to allow quadruped locomotion. In this deliverable we continue with the simulation studies on the application of the different morphological computation strategies to control a robotic system