scholarly journals A decentralized control scheme for orchestrating versatile arm movements in ophiuroid omnidirectional locomotion

2011 ◽  
Vol 9 (66) ◽  
pp. 102-109 ◽  
Author(s):  
Wataru Watanabe ◽  
Takeshi Kano ◽  
Shota Suzuki ◽  
Akio Ishiguro
Keyword(s):  
Decentralized Control ◽  
Coupled Oscillators ◽  
Design Methodology ◽  
Arm Movements ◽  
Rhythmic Movements ◽  
Role Assignment ◽  
Rotator Model ◽  
Proposed Model ◽  
Control Scheme ◽  
Living Organisms

Autonomous decentralized control is a key concept for understanding the mechanism underlying the adaptive and versatile behaviour of animals. Although the design methodology of decentralized control based on a dynamical system approach that can impart adaptability by using coupled oscillators has been proposed in previous studies, it cannot reproduce the versatility of animal behaviours comprehensively. Therefore, our objective is to understand behavioural versatility from the perspective of well-coordinated rhythmic and non-rhythmic movements. To this end, we focus on ophiuroids as a simple good model of living organisms that exhibit spontaneous role assignment of rhythmic and non-rhythmic arm movements, and we model such arm movements by using an active rotator model that can describe both oscillatory and excitatory properties. Simulation results show that the spontaneous role assignment of arm movements is successfully realized by using the proposed model, and the simulated locomotion is qualitatively equivalent to the locomotion of real ophiuroids. This fact can potentially facilitate a better understanding of the control mechanism responsible for the orchestration of versatile arm movements in ophiuroid omnidirectional locomotion.

scholarly journals Decentralized Control of Ophiuroid Robot That Enables Self-organized Role Assignment of Arm Movements

2013 ◽  
Vol 49 (1) ◽  
pp. 48-53
Author(s):  
Wataru WATANABE ◽  
Shota SUZUKI ◽  
Takeshi KANO ◽  
Akio ISHIGURO
Keyword(s):  
Decentralized Control ◽  
Arm Movements ◽  
Role Assignment ◽  
Self Organized

Generating Situation-Dependent Behavior: Decentralized Control of Multi-Functional Intestine-Like Robot that can Transport and Mix Contents

2013 ◽  
Vol 25 (5) ◽  
pp. 871-876 ◽  
Author(s):  
Takeshi Kano ◽  
◽  
Toshihiro Kawakatsu ◽  
Akio Ishiguro ◽  
◽  
...  
Keyword(s):  
Decentralized Control ◽  
Coupled Oscillators ◽  
Sensory Feedback ◽  
Specific Task ◽  
Physical Conditions ◽  
Dependent Behavior ◽  
Intestinal Movement ◽  
Control Scheme ◽  
Different Types ◽  
Simulation Results

Most robots are designed to perform a specific task in a predefined environment and have difficulty in producing situation-dependent behavior. To tackle this problem, we focus here on a mammal intestine that either transports or mixes the contents depending on the encountered circumstances. We propose a simple model for the intestinal movement and design an autonomous decentralized control scheme for an intestine-like robot by using coupled oscillators with local sensory feedback. Simulation results show that different types of motions are generated depending on the the physical conditions of the intestine and its contents. Our simulated robot does not require any input from a higher center to switch between different types of motions but determines autonomously which motion to generate. This study thus paves the way for developing “multi-functional robots” whose behavior is changed flexibly and spontaneously depending on circumstances.

Dynamic output feedback control for nonlinear large-scale interconnected systems

2020 ◽  
Vol 39 (4) ◽  
pp. 801-821
Author(s):  
Ezzeddine Touti ◽  
Ali Sghaier Tlili ◽  
Muhannad Almutiry
Keyword(s):  
Decentralized Control ◽  
Output Feedback ◽  
Large Scale ◽  
Optimization Problem ◽  
Lyapunov Theory ◽  
Interconnected Systems ◽  
Dynamic Output Feedback ◽  
Content Type ◽  
Dynamic Output ◽  
Control Scheme

Purpose This paper aims to focus on the design of a decentralized observation and control method for a class of large-scale systems characterized by nonlinear interconnected functions that are assumed to be uncertain but quadratically bounded. Design/methodology/approach Sufficient conditions, under which the designed control scheme can achieve the asymptotic stabilization of the augmented system, are developed within the Lyapunov theory in the framework of linear matrix inequalities (LMIs). Findings The derived LMIs are formulated under the form of an optimization problem whose resolution allows the concurrent computation of the decentralized control and observation gains and the maximization of the nonlinearity coverage tolerated by the system without becoming unstable. The reliable performances of the designed control scheme, compared to a distinguished decentralized guaranteed cost control strategy issued from the literature, are demonstrated by numerical simulations on an extensive application of a three-generator infinite bus power system. Originality/value The developed optimization problem subject to LMI constraints is efficiently solved by a one-step procedure to analyze the asymptotic stability and to synthesize all the control and observation parameters. Therefore, such a procedure enables to cope with the conservatism and suboptimal solutions procreated by optimization problems based on iterative algorithms with multi-step procedures usually used in the problem of dynamic output feedback decentralized control of nonlinear interconnected systems.

scholarly journals Image-based Visual Servoing for Optimal Grasping

2001 ◽  
Vol 13 (5) ◽  
pp. 479-487
Author(s):  
Hideo Fujimoto ◽  
◽  
Liu-Cun Zhu ◽  
Karim Abdel-Malek ◽  
Keyword(s):  
Visual Servoing ◽  
Ccd Camera ◽  
Servo Control ◽  
Visually Guided ◽  
Grasp Planning ◽  
Vector Processing ◽  
Vector Error ◽  
Proposed Model ◽  
Control Scheme ◽  
Kinematic Errors

One of the most common tasks in robotics is grasping. Although the formulation of optimal grasping has been addressed using a variety of approaches, there are only a few grasping systems that can operate in uncertain dynamic environments. In this paper, we present an image-based visual servoing method and system for optimal object grasping by introducing the method of visual vectors. A CCD camera mounted on a robot end-effector constructs the visually guided servo control system and the control scheme lends itself to task-level specification of manipulation goals. The proposed approach integrates vision, grasp planning, and vision=guided control to accomplish the optimal grasping task. The grasping task is to control the robot so the vectors of the end-effector's landmark (e.g., finger vector) and a target object's grasp coincide. These vectors can be used to perform the work of a stable grasping of an object that is presented in an unstructured manner. Visual vectors in image frame are obtained by analyzing the object's image and projection. Our objective in implementing vector processing is to estimate the vector error between the finger and grasp vectors, and to control the robot to eliminate kinematic errors. The proposed model is illustrated through examples and its effectiveness is validated using computer simulation.

An approach towards decentralized control of cooperating non-autonomous multiple robots

Robotica ◽  
2000 ◽  
Vol 18 (5) ◽  
pp. 495-504 ◽  
Author(s):  
Khalid Munawar ◽  
Masayoshi Esashi ◽  
Masaru Uchiyama
Keyword(s):  
Decentralized Control ◽  
Degrees Of Freedom ◽  
Real Life ◽  
Robotic Systems ◽  
Present System ◽  
Multiple Robots ◽  
Experimental Implementation ◽  
Control Scheme ◽  
The Common ◽  
Event Based

This paper introduces an event-based decentralized control scheme for the cooperation between multiple manipulators. This is in contrast to the common practice of using only centralized controls for such cooperation which, consequently, greatly limit the flexibility of robotic systems. The manipulators used in the present system are very simple with only two degrees of freedom, while even one of them is passive. Moreover these manipulators use very few and commonly available sensors only. Computer simulations indicated the applicability of the event-based decentralized control scheme for multi-manipulator cooperation, while real-life experimental implementation has proved that the proposed decentralized control scheme is fairly applicable for very simple and even under-actuated systems too. Hence, this work has opened new doors towards further research in this area. The proposed control scheme is expected to be equally applicable for any mobile or immobile multi-robotic system.

Investigating the effects of operators on warranty cost under sales delay conditions

2018 ◽  
Vol 24 (2) ◽  
pp. 244-259
Author(s):  
Sepideh Eskandari Dorabati ◽  
Ali Zeinal Hamadani ◽  
Hamed Fazlollahtabar
Keyword(s):  
Data Analysis ◽  
Design Methodology ◽  
Claims Data ◽  
Time Interval ◽  
Content Type ◽  
Proposed Model ◽  
Warranty Cost ◽  
Warranty Costs ◽  
Warranty Claims ◽  
Claims Data Analysis

Purpose Due to the fact that the non-standard products, being used by customers, may cause failures in products with sales delays, which naturally affect the warranty policy. Thus, it seems to be necessary to study these two concepts simultaneously. The paper aims to discuss these issues. Design/methodology/approach In this paper, a model is developed for estimating the expected warranty costs under sales delay conditions when two operator costs (failing but not reported and non-failing but reported) are included. Findings The proposed model is validated using a numerical example for a two types of intermittent and fatal failures occur under a non-renewing warranty policy. Originality/value Sales delay is the time interval between the date of production and the date of sale. Most reported literature on warranty claims data analysis related to sales delay have mainly focussed on estimating the probability distribution of the sales delay.

Proposing micro-macro HRM strategies to overcome challenges of workforce diversity and deviance in ASEAN

2018 ◽  
Vol 37 (1) ◽  
pp. 6-26 ◽  
Author(s):  
Pooja Malik ◽  
Usha Lenka ◽  
Debashish Kumar Sahoo
Keyword(s):  
Systematic Review ◽  
Conceptual Framework ◽  
Design Methodology ◽  
Southeast Asian ◽  
Workplace Deviance ◽  
Workforce Diversity ◽  
Review Of Literature ◽  
Content Type ◽  
Proposed Model ◽  
Key Word

Purpose The purpose of this paper is to propose a conceptual framework associating globalization, workforce diversity, and deviance and suggest micro-macro HRM strategies to overcome challenges associated with the workforce diversity and workplace deviance. Design/methodology/approach A systematic review of literature of past 25 years was carried out with the key word “globalization, workforce diversity, and deviance” from several electronic databases. Findings Findings propose micro-macro HRM strategies to be adopted by HR practitioners in Association of Southeast Asian Nations (ASEAN) organizations to manage workforce diversity and deviance in the age of globalization. Research limitations/implications The challenges due to workforce diversity may get worse because ASEAN is more incongruent in terms of phases of economic, social, cultural, and political advancement. Therefore, proposed model can be tested and compared in different ASEAN organizations. Originality/value There is a dearth of literature associating globalization, workforce diversity, and deviance. This paper bridges this gap by proposing a conceptual framework in the ASEAN context and suggests micro-macro HRM strategies to be adopted by HRM practitioners to overcome associated challenges with workforce diversity and deviance.

Decentralized Control for Swarm Robots That Can Effectively Execute Spatially Distributed Tasks

2020 ◽  
Vol 26 (2) ◽  
pp. 242-259 ◽  
Author(s):  
Takeshi Kano ◽  
Eiichi Naito ◽  
Takenobu Aoshima ◽  
Akio Ishiguro
Keyword(s):  
Decentralized Control ◽  
Internal State ◽  
Search And Rescue ◽  
Multiple Robots ◽  
Rescue Operation ◽  
Control Scheme ◽  
Swarm Robots ◽  
Multiple Tasks ◽  
Spatially Distributed ◽  
Distributed Tasks

A swarm robotic system is a system in which multiple robots cooperate to fulfill a macroscopic function. Many swarm robots have been developed for various purposes. This study aims to design swarm robots capable of executing spatially distributed tasks effectively, which can be potentially used for tasks such as search-and-rescue operation and gathering scattered garbage in rooms. We propose a simple decentralized control scheme for swarm robots by extending our previously proposed non-reciprocal-interaction-based model. Each robot has an internal state, called its workload. Each robot first moves randomly to find a task, and when it does, its workload increases, and then it attracts its neighboring robots to ask for their help. We demonstrate, via simulations, that the proposed control scheme enables the robots to effectively execute multiple tasks in parallel under various environments. Fault tolerance of the proposed system is also demonstrated.

scholarly journals Complementary spatial and timing control in rhythmic arm movements

2019 ◽  
Vol 121 (4) ◽  
pp. 1543-1560 ◽  
Author(s):  
Robert W. Nickl ◽  
M. Mert Ankarali ◽  
Noah J. Cowan
Keyword(s):  
Visual Feedback ◽  
Haptic Feedback ◽  
Motor Behavior ◽  
Hand Movement ◽  
Arm Movements ◽  
Timing Synchronization ◽  
Sufficient Information ◽  
Spatial Accuracy ◽  
Rhythmic Movements ◽  
Spatial Error

Volitional rhythmic motor behaviors such as limb cycling and locomotion exhibit spatial and timing regularity. Such rhythmic movements are executed in the presence of exogenous visual and nonvisual cues, and previous studies have shown the pivotal role that vision plays in guiding spatial and temporal regulation. However, the influence of nonvisual information conveyed through auditory or touch sensory pathways, and its effect on control, remains poorly understood. To characterize the function of nonvisual feedback in rhythmic arm control, we designed a paddle juggling task in which volunteers bounced a ball off a rigid elastic surface to a target height in virtual reality by moving a physical handle with the right hand. Feedback was delivered at two key phases of movement: visual feedback at ball peaks only and simultaneous audio and haptic feedback at ball-paddle collisions. In contrast to previous work, we limited visual feedback to the minimum required for jugglers to assess spatial accuracy, and we independently perturbed the spatial dimensions and the timing of feedback. By separately perturbing this information, we evoked dissociable effects on spatial accuracy and timing, confirming that juggling, and potentially other rhythmic tasks, involves two complementary processes with distinct dynamics: spatial error correction and feedback timing synchronization. Moreover, we show evidence that audio and haptic feedback provide sufficient information for the brain to control the timing synchronization process by acting as a metronome-like cue that triggers hand movement. NEW & NOTEWORTHY Vision contains rich information for control of rhythmic arm movements; less is known, however, about the role of nonvisual feedback (touch and sound). Using a virtual ball bouncing task allowing independent real-time manipulation of spatial location and timing of cues, we show their dissociable roles in regulating motor behavior. We confirm that visual feedback is used to correct spatial error and provide new evidence that nonvisual event cues act to reset the timing of arm movements.

An areal openness model (AOM) for quantifying the “openness” of floor plans

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Zoraya Roldán Rockow ◽  
Brandon E. Ross
Keyword(s):  
Real World ◽  
Design Methodology ◽  
Floor Plan ◽  
Existing Buildings ◽  
Content Type ◽  
Alternative Plan ◽  
Proposed Model ◽  
Reasonable Approach ◽  
Floor Plans

PurposeThis paper aims to describe and demonstrate a quantitative areal openness model (AOM) for measuring the openness of floor plans. Creation of the model was motivated by the widely reported but rarely quantified link between openness and adaptability.Design/methodology/approachThe model calculates values for three indicators: openness score (OS), weighted OS (WOS) and openness potential (OP). OS measures the absence of obstructions (walls, chases, columns) that separate areas in a floor plan. WOS measures the number of obstructions while also accounting for the difficulty of removing them. OP measures the potential of a floor plan to become more open. Indicators were calculated for three demolished case study buildings and for three adapted buildings. The case study buildings were selected because openness – or lack thereof – contributed to the owners' decisions to demolish or adapt.FindingsOpenness indicators were consistent with the real-world outcomes (adaptation or demolition) of the case study buildings. This encouraging result suggests that the proposed model is a reasonable approach for comparing the openness of floor plans and evaluating them for possible adaptation or demolition.Originality/valueThe AOM is presented as a tool for facility managers to evaluate inventories of existing buildings, designers to compare alternative plan layouts and researchers to measure openness of case studies. It is intended to be sufficiently complex as to produce meaningful results, relatively simple to apply and readily modifiable to suit different situations. The model is the first to calculate floor plan openness within the context of adaptability.

Sign in / Sign up

Export Citation Format

Share Document