Intelligent Approach to Floor Vibration Control

2005 ◽  
Author(s):  
Janice L. Martell ◽  
Arya Ebrahimpour ◽  
Marco P. Schoen
Keyword(s):  
Cantilever Beam ◽  
Human Perception ◽  
Shopping Mall ◽  
Optimal Placement ◽  
Sensors And Actuators ◽  
Control Approach ◽  
Novel Approach ◽  
Floor Vibration ◽  
High Level ◽  
Floor System

Genetic Algorithms (GAs) have been used to solve a multiple of engineering problems with the civil engineering applications ranging from optimal placement of sensors and actuators on structures to pipeline layouts. GAs are especially useful in finding optimal solutions to problems that have many parameters with complex search spaces and a high level of interaction among the describing parameters. The novel experimental control approach presented in this paper uses a GA and a piezoelectric actuator to control the vibration of an aluminum cantilever beam. This set-up is based on a floor vibration problem, where the human perception of vibration dictates the sensitivities in the cost function of the GA. Lightweight floors can be excited by occupant activities such as walking, jumping and dancing. Humans are especially sensitive to vibrations in the range of 4 to 8 Hz. The occupancy of a floor system — whether the floor is used in an office, a shopping mall, or a ballroom — determines the degree to which humans are annoyed by the vibration. In this paper, the GA based control limits the peak acceleration within a predefined bandwidth. Since the cantilever beam has a higher natural frequency than a lightweight floor system a bandwidth of approximately 1.6–15.9 Hz (10–100 rad/s) is used as the frequency range to control. The control to be designed will be a genetic algorithm-robust controller. The analytical results indicate that this novel approach works well.

scholarly journals Transparent Data Reduction in Networked Telepresence and Teleaction Systems. Part I: Communication without Time Delay

2007 ◽  
Vol 16 (5) ◽  
pp. 523-531 ◽  
Author(s):  
Sandra Hirche ◽  
Peter Hinterseer ◽  
Eckehard Steinbach ◽  
Martin Buss
Keyword(s):  
Time Delay ◽  
Data Reduction ◽  
Network Traffic ◽  
Human Perception ◽  
Signal Amplitude ◽  
Perception Threshold ◽  
Control Approach ◽  
Novel Approach ◽  
Communication Time ◽  
Video And Audio

Limited communication resources represent a major challenge in networked tele-presence and teleaction systems. Video and audio compression schemes are well advanced employing models of human perception. In contrast to that haptic data reduction schemes are rather poorly treated in the known literature. This article introduces a novel approach to reduce network traffic in haptic telepresence systems exploiting limits in human haptic perception. With the proposed deadband control approach, data packets are transmitted only if the signal change exceeds a signal amplitude dependent perception threshold. Experimental user studies show that an average network traffic reduction of up to 85% can be achieved without significantly impairing the perception of the remote environment. The assumption throughout this article is that there is no communication time delay.

Optimal Placement of Sensors and Actuators in Cluster Control of Acoustic Potential Energy in a Cavity

2010 ◽  
Author(s):  
M. Jalali ◽  
A. R. Ohadi
Keyword(s):  
Potential Energy ◽  
Noise Suppression ◽  
Control Method ◽  
Acoustic Noise ◽  
Mimo System ◽  
Optimal Placement ◽  
Sensors And Actuators ◽  
Disturbing Force ◽  
Control Approach ◽  
Acoustic Cavity

This paper aims the cluster control of acoustic potential energy in a structural/acoustic cavity. The cavity consists of five rigid walls and one flexible panel with clamped boundary conditions on all four edges. It is desired to suppress the acoustic noise within the cavity, produced by a disturbing force or plane wave. In order to perform noise suppression, both acoustic and structural actuators can be used, while only acoustic sensors are necessary for measurement. Cluster control approach classifies acoustic and structural modes such that they interfere if and only if they belong to the same cluster. Providing methods to actuate and measure each of these clusters individually, cluster control enables us to implement a multi-SISO system as opposed to a MIMO system, which can significantly reduce computational load on the controller. This paper also investigates the optimal placement of sensors and actuators for further noise suppression. It is shown that optimization is critically important when cluster control method is used. Optimal placement of sensors and actuators helps to improve the noise suppression, without increasing the cost of control system equipments. In order to locate the optimum positions, the genetic algorithm (GA) is employed. The effect of optimization on acoustic potential energy suppression is discussed using numerical simulations.

Exploring The Effect of Visual Information Degradation on Human Perception and Performance In A Human-Telerobot System

2020 ◽  
Vol 64 (1) ◽  
pp. 1302-1307
Author(s):  
Richard Stone ◽  
Minglu Wang ◽  
Thomas Schnieders ◽  
Esraa Abdelall
Keyword(s):  
Visual Information ◽  
Human Perception ◽  
Low Level ◽  
Hit Rate ◽  
Word Level ◽  
Level Of Automation ◽  
Significant Difference ◽  
Human Operators ◽  
And Performance ◽  
High Level

Human-robotic interaction system are increasingly becoming integrated into industrial, commercial and emergency service agencies. It is critical that human operators understand and trust automation when these systems support and even make important decisions. The following study focused on human-in-loop telerobotic system performing a reconnaissance operation. Twenty-four subjects were divided into groups based on level of automation (Low-Level Automation (LLA), and High-Level Automation (HLA)). Results indicated a significant difference between low and high word level of control in hit rate when permanent error occurred. In the LLA group, the type of error had a significant effect on the hit rate. In general, the high level of automation was better than the low level of automation, especially if it was more reliable, suggesting that subjects in the HLA group could rely on the automatic implementation to perform the task more effectively and more accurately.

scholarly journals Towards a contemporary player learning in development framework for sports practitioners

2021 ◽  
pp. 174795412110023
Author(s):  
Mark O Sullivan ◽  
Carl T Woods ◽  
James Vaughan ◽  
Keith Davids
Keyword(s):  
Linear Process ◽  
Task Environment ◽  
Coach Education ◽  
Development Framework ◽  
Novel Approach ◽  
Non Linear ◽  
And Performance ◽  
Learning Development ◽  
High Level ◽  
User Friendly

As it is appreciated that learning is a non-linear process – implying that coaching methodologies in sport should be accommodative – it is reasonable to suggest that player development pathways should also account for this non-linearity. A constraints-led approach (CLA), predicated on the theory of ecological dynamics, has been suggested as a viable framework for capturing the non-linearity of learning, development and performance in sport. The CLA articulates how skills emerge through the interaction of different constraints (task-environment-performer). However, despite its well-established theoretical roots, there are challenges to implementing it in practice. Accordingly, to help practitioners navigate such challenges, this paper proposes a user-friendly framework that demonstrates the benefits of a CLA. Specifically, to conceptualize the non-linear and individualized nature of learning, and how it can inform player development, we apply Adolph’s notion of learning IN development to explain the fundamental ideas of a CLA. We then exemplify a learning IN development framework, based on a CLA, brought to life in a high-level youth football organization. We contend that this framework can provide a novel approach for presenting the key ideas of a CLA and its powerful pedagogic concepts to practitioners at all levels, informing coach education programs, player development frameworks and learning environment designs in sport.

scholarly journals Deep Reinforcement Learning for End-to-End Local Motion Planning of Autonomous Aerial Robots in Unknown Outdoor Environments: Real-Time Flight Experiments

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2534
Author(s):  
Oualid Doukhi ◽  
Deok-Jin Lee
Keyword(s):  
Reinforcement Learning ◽  
Real Time ◽  
Autonomous Navigation ◽  
Control Technique ◽  
Local Motion ◽  
Aerial Robots ◽  
Novel Approach ◽  
Outdoor Environments ◽  
Aerial Vehicle ◽  
High Level

Autonomous navigation and collision avoidance missions represent a significant challenge for robotics systems as they generally operate in dynamic environments that require a high level of autonomy and flexible decision-making capabilities. This challenge becomes more applicable in micro aerial vehicles (MAVs) due to their limited size and computational power. This paper presents a novel approach for enabling a micro aerial vehicle system equipped with a laser range finder to autonomously navigate among obstacles and achieve a user-specified goal location in a GPS-denied environment, without the need for mapping or path planning. The proposed system uses an actor–critic-based reinforcement learning technique to train the aerial robot in a Gazebo simulator to perform a point-goal navigation task by directly mapping the noisy MAV’s state and laser scan measurements to continuous motion control. The obtained policy can perform collision-free flight in the real world while being trained entirely on a 3D simulator. Intensive simulations and real-time experiments were conducted and compared with a nonlinear model predictive control technique to show the generalization capabilities to new unseen environments, and robustness against localization noise. The obtained results demonstrate our system’s effectiveness in flying safely and reaching the desired points by planning smooth forward linear velocity and heading rates.

scholarly journals Carebots

2016 ◽  
Vol 138 (09) ◽  
pp. S8-S13 ◽  
Author(s):  
Thiago Marinho ◽  
Christopher Widdowson ◽  
Amy Oetting ◽  
Arun Lakshmanan ◽  
Hang Cui ◽  
...  
Keyword(s):  
Older Adults ◽  
Multidisciplinary Approach ◽  
Human Perception ◽  
The Elderly ◽  
Comfort Level ◽  
Robot System ◽  
Perceived Safety ◽  
High Level ◽  
Future Work ◽  
Flying Robots

This article demonstrates a multidisciplinary approach that proposes to augment future caregiving by prolonged independence of older adults. The human–robot system allows the elderly to cooperate with small flying robots through an appropriate interface. ASPIRE provides a platform where high-level controllers can be designed to provide a layer of abstraction between the high-level task requests, the perceptual needs of the users, and the physical demands of the robotic platforms. With a robust framework that has the capability to account for human perception and comfort level, one can provide perceived safety for older adults, and further, add expressively that facilitates communication and interaction continuously throughout the stimulation. The proposed framework relies on an iterative process of low-level controllers design through experimental data collected from psychological trials. Future work includes the exploration of multiple carebots to cooperatively assist in caregiving tasks based on human-centered design approach.

Optimal Placement of Piezoelectric Sensors and Actuators for Controlled Flexible Linkage Mechanisms

2005 ◽  
Vol 128 (2) ◽  
pp. 256-260 ◽  
Author(s):  
Xianmin Zhang ◽  
Arthur G. Erdman
Keyword(s):  
Vibration Control ◽  
Simulation Analysis ◽  
Active Vibration Control ◽  
Optimal Placement ◽  
Control Effect ◽  
Sensors And Actuators ◽  
Piezoelectric Sensors And Actuators ◽  
Active Vibration ◽  
Flexible Mechanism ◽  
Flexible Linkage

The optimal placement of sensors and actuators in active vibration control of flexible linkage mechanisms is studied. First, the vibration control model of the flexible mechanism is introduced. Second, based on the concept of the controllability and the observability of the controlled subsystem and the residual subsystem, the optimal model is developed aiming at the maximization of the controllability and the observability of the controlled modes and minimization of those of the residual modes. Finally, a numerical example is presented, which shows that the proposed method is feasible. Simulation analysis shows that to achieve the same control effect, the control system is easier to realize if the sensors and actuators are located in the optimal positions.

scholarly journals A fast and efficient MATLAB-based MPM solver: fMPMM-solver v1.1

2020 ◽  
Vol 13 (12) ◽  
pp. 6265-6284
Author(s):  
Emmanuel Wyser ◽  
Yury Alkhimenkov ◽  
Michel Jaboyedoff ◽  
Yury Y. Podladchikov
Keyword(s):  
Cantilever Beam ◽  
Large Scale ◽  
Solid Mechanics ◽  
Large Deformations ◽  
Material Point ◽  
Snow Avalanches ◽  
High Level Language ◽  
Numerical Accuracy ◽  
Computational Performance ◽  
High Level

Abstract. We present an efficient MATLAB-based implementation of the material point method (MPM) and its most recent variants. MPM has gained popularity over the last decade, especially for problems in solid mechanics in which large deformations are involved, such as cantilever beam problems, granular collapses and even large-scale snow avalanches. Although its numerical accuracy is lower than that of the widely accepted finite element method (FEM), MPM has proven useful for overcoming some of the limitations of FEM, such as excessive mesh distortions. We demonstrate that MATLAB is an efficient high-level language for MPM implementations that solve elasto-dynamic and elasto-plastic problems. We accelerate the MATLAB-based implementation of the MPM method by using the numerical techniques recently developed for FEM optimization in MATLAB. These techniques include vectorization, the use of native MATLAB functions and the maintenance of optimal RAM-to-cache communication, among others. We validate our in-house code with classical MPM benchmarks including (i) the elastic collapse of a column under its own weight; (ii) the elastic cantilever beam problem; and (iii) existing experimental and numerical results, i.e. granular collapses and slumping mechanics respectively. We report an improvement in performance by a factor of 28 for a vectorized code compared with a classical iterative version. The computational performance of the solver is at least 2.8 times greater than those of previously reported MPM implementations in Julia under a similar computational architecture.

scholarly journals Reconnecting a Fragmented Monument through Digital Mapping: The City Walls of Athens

2019 ◽  
Vol 2 (2) ◽  
pp. 177-195
Author(s):  
Markos Katsianis ◽  
Stamatina Lampraki ◽  
Anna-Maria Theocharaki ◽  
Maria Pigaki ◽  
Leda Costaki ◽  
...  
Keyword(s):  
Digital Media ◽  
Archaeological Sites ◽  
Geospatial Technologies ◽  
Archaeological Investigation ◽  
Digital Mapping ◽  
Cadastral Maps ◽  
Novel Approach ◽  
City Walls ◽  
High Level ◽  
The City

The fortifications of Athens have been a recurrent theme of archaeological investigation. In the past two centuries, parts of the walls have been located during rescue interventions at numerous sites in the urban fabric. At present, the visibility of the entire monument remains rather low as the traces of the walls are hidden beneath the modern city, marginalized within larger archaeological sites or preserved entirely by record. Despite the high level of scholarly work devoted to synthesize the available material, the volume of information accumulated over the years requires a novel approach that would systematize different types of evidence using digital media. In this respect, we attempt to revisit the city walls of Athens through the use of geospatial technologies. We target the informed development of an efficient GIS platform to record, store, integrate, explore and eventually disseminate resources on the Athenian fortifications. Our research employs published and archival sources (e.g. excavation drawings) in combination with historical maps (e.g. early cadastral maps, first maps of modern Athens) and complementary historical evidence (e.g. writings, illustrations, photography) to locate, document and integrate in space and time available data on lost and surviving fortification remains.

Generic Modular Operations for Virtual Manufacturing Process Engineering

1997 ◽  
Author(s):  
David E. Lee ◽  
H. Thomas Hahn
Keyword(s):  
Manufacturing Process ◽  
Process Development ◽  
Process Engineering ◽  
Virtual Manufacturing ◽  
Control Approach ◽  
Computational Costs ◽  
Direct Mechanism ◽  
Novel Approach ◽  
Operation Control ◽  
Virtual Process

Abstract In order to address the computational costs of modeling and analyzing manufacturing processes, a novel approach to virtual manufacturing process engineering using generic modular operations is presented. Relying on a state based representation of operation control for a simplified virtual manufacturing workcell, the valid states for each sequence of generic modular operations are aggregated and both operation state and processing constraints applied to specify the subtasks required to complete each step in a product’s process plan. By adopting this state based control approach, virtual process engineering provides a direct mechanism to map virtual process representations onto actualized processes. Using these generic modular operations and their temporal and processing dependencies, the computationally complex elements of virtual manufacturing process simulation can be directly identified and an architecture for virtual process development specified. Examples from both machining and assembly processes are provided.

Sign in / Sign up

Export Citation Format

Share Document