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The robotic servicing of satellites on-orbit will play an important role in extending their lifespan and mitigating space debris expansion. However, most maneuvers related to these goals present a set of unique challenges which are hard to assess in reality. On the other hand, a reliable prediction of the feasibility of servicing maneuvers is increasingly required. This paper presents a simulation-driven...
This paper describes the investigation of linear and parametric iterative learning control (ILC) methods with an integrated computed torque control approach and the application in a mobile multi-body service robot. In addition to the controller structure, the development of the nonlinear dynamic model and the trajectory generation for the robot-configuration control are briefly explained.
The delta parallel mechanism has proven to be a very successful parallel robot design and a number of variants have been proposed in the literature. Taking advantage of its simple construction and the intrinsic features such as high stiffness and accuracy, delta robots play an important role both in the fields of industrial robots and academical fields. In this paper, dynamic modeling and control...
Here we describe the ongoing development of a unique computer model to simulate the upper-limb during sinusoidal tracking activity on the TheraDrive, a 1 degree of freedom (DOF) haptic stroke rehabilitation system. The model predicts longitudinal muscle forces while simulating Thera-Drive activity to better understand the physiological changes (e.g. muscle dynamics) that arise from stroke and subsequent...
The day-ahead unit-commitment (UC)-based market-clearing (MC) is widely acknowledged to be the most economically efficient mechanism for scheduling resources in power systems.
Successful deployment of a snake robot in search and rescue tasks requires the capability of generating controls which can adapt to unknown environments in real-time. However, available motion generation techniques can be computationally expensive and lack the ability to adapt to the surroundings. This work considers modeling the rolling motion of a snake robot by applying the Bellows model with computation...
The MOBOT* project aims to develop assistive devices that support elderly patients with mobility disabilities during gait and sit-to-stand (STS) transfer. The device is supposed to help such patients to maintain an independent life through mobility as well as to regain basic life skills since self-effort is encouraged. Situation-adapted optimal assistance will be provided by the device both proactively...
In this paper two predictive controllers for non-linear systems are presented. Both methods — ELPC and MELPC — are based on a local linearisation of the process at each sampling instant, thus, a priori, should perform better than the controllers designed in terms of a single linearisation about an operating point. On the other hand, their linear formulation leads to computation times much shorter...
Exercise based rehabilitation plays a vital role in the recovery of various conditions, such as stroke, Parkinson's disease (PD), chronic pain, and so on. Recently, tele-rehabilitation has become increasingly popular quantitative nature in assessments particularly for systematic monitoring of progress as well as cost saving for the patients as well as for the health care sector at large. However,...
In computed torque control, robot dynamics are predicted by dynamic models. This enables more compliant control, as the gains of the feedback term can be lowered, because the task of compensating for robot dynamics is delegated from the feedback to the feedforward term. Previous work has shown that Gaussian process regression is an effective method for learning computed torque control, by setting...
To equip a robot with various required skills so that to serve human society, plenty of research have been performed and successfully applied from both theoretical and practical aspects for decades. Usually, a robot with several skills needs to recall a different controller or model parameters to fit the new circumstance as task to be fulfilled or environment changes. Therefore, how to smoothly shift...
One of the fundamental problems in developmental robotics relates to the progressive spontaneous acquisition of motor abilities by an organism. Throughout this process, the speed of acquiring abilities, which we term ‘learnability’, is strongly limited by the dimensionality of the sensori-motor space; this in turn could affect the survival of an organism. In this paper, we tackle the problem of dimensional...
Human action analysis has achieved great success especially with the recent development of advanced sensors and algorithms that can effectively track the body joints. Temporal motion of body joints carries crucial information about human actions. However, current dynamic models typically assume stationary local transition and therefore are limited to local dynamics. In contrast, we propose a novel...
In order to increase the workspace size of parallel robots (largely reduced by the presence of singularities) several solutions have been proposed. One promising solution consists in the definition of optimal trajectories that ensure the non degeneracy of the dynamic model in the singularity and therefore are able to cross the Type 2 singularities. Those works are based on the computation of the optimal...
Modular robots, which are systems made of many robotic modules, can utilize various types of locomotion. Different approaches can be used to generate these basic motion skills — motion primitives. To move in a complex environment, several motion primitives are needed and a mechanism to switch them is required. This can be realized using a high-level motion planning. To enable autonomous operation...
Biped robot locomotion is one of the most challenging fields in humanoid robots. Many gait generation models are introduced to have stable walking similar to human. One of the gait generation models is Central Pattern Generator (CPG) which can produce complex nonlinear oscillation as a pattern for walking. In this paper joints trajectories are calculated by using polynomial equations for the support...
An alternative approach to model changes in human motor functions during cognition and rehabilitation is proposed in this paper. The motivation behind this research is to provide one with the numerical scale to measure progress of rehabilitation or cognition. Main distinctive feature of the proposed approach is, that unlike many other techniques it do not concentrate its attention on precise modeling...
Nowadays many robotic tasks require close and compliant tracking of desired positions, paths, or forces. To achieve these goals, model-based control schemes provide a possible solution, allowing to directly consider the nonlinear dynamics. One of the key challenges, however, is the derivation of suitable models, which allow sufficiently fast evaluation, as well as the parameterization of these models...
Cloud federation is the next step in creating a new cloud computing ecosystem. The absence of suitable business models for federation managers is hindering the wide deployment of this critical feature. In this paper we will study existing federation managers, specifically CCFM (Cross-Cloud Federation Manager) and analyze its strengths and limitations. To overcome its limitations and make cloud federation...
In this study, we apply an optimal motor control model to the step-tracking wrist movement task. The motor control model was originally proposed for arm reaching movement and succeeded in predicting experimentally observed features in movement kinematics. As is the case with arm reaching movement, step-tracking wrist movement includes redundancy in trajectory formation. Therefore, step-tracking wrist...
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