Top PDF Dynamic Control of Kinematically Redundant Robotic Manipulators

Neural Network Controller for Two links- Robotic Manipulator Control with Different Load

Neural Network Controller for Two links- Robotic Manipulator Control with Different Load

development of robotic applications, in industrial therefore dynamic control of robot manipulators is one of the most important and challenging fields of robotics, in the recent years using intelligence control such as fuzzy control, Neural Network, Neuro Fuzzy and because that they can control nonlinear systems that would be difficult or impossible to model mathematically. In the recently years In Dynamic control of robot have been utilized in many researchers work in this area. Such as Lianfang Tian et al use a neural network approach for the motion control of constrained flexible manipulators robots [1]. Yi , et al have investigated the robustness and stability of a fuzzy logic controller applied to a robotic manipulator with uncertainties such as friction, unmodeled dynamics, and external disturbance etc [2], Kumbla et al have implemented hierarchical control on robotic manipulator using fuzzy logic [3].
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Dynamic modeling and simulation of a flexible robotic manipulator

Dynamic modeling and simulation of a flexible robotic manipulator

One matter of increasing interest to control engineers are the effects of flexibility in lightweight manipulators, machine tools and space structures, etc. To achieve the high performance requirements such as high-speed operation, increased accuracy in positioning, lower energy consump- tion, less weight, and safer operation due to reduced inertia flexible manipulators are recommended. However, in mod- eling and controlling this manipulator the flexibility of its components must be considered. 1–4 The incorporation of the

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Control of an anthropomorphic manipulator involved in physical human-robot interaction

Control of an anthropomorphic manipulator involved in physical human-robot interaction

The objective of this chapter is to develope a novel method which enables control- ling of anthropomorphic mobile manipulators for pHRI tasks in dynamic environments. By proposing a Virtual Elastic System for linking a 7-DOF anthropomorphic robotic arm with a nonholomic mobile platform, a powerful control strategy is achieved through an integration of different control methods for each system. More specifically, movements of the end effector, which are coordinated through contact forces and torques exerted by the human, are controlled by using Inverse Differential Kinematics (see, e.g. [Wang et al., 2010], [Papadopoulos & Poulakakis, 2000]) while the mobile platform is kept away from obstacles with Dynamical Systems (see, e.g. [Bicho et al., 2000], [Soares et al., 2007]). Ex- periments in Human-Robot Interaction scenarios have proved the developed method to be a powerful control approach for mobile manipulators in tasks which involve physical contacts with human and also requiring free obstacle motions for the whole system. Ex- tensions of the Virtual Elastic System for holonomic mobile platforms or higher degrees of freedom manipulators are presented through simulations to give insights about how to apply the Virtual Elastic System for other types of mobile manipulators.
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Quadratic Dynamic Matrix Control of Isopropyl Acetate Reactive Distillation Column

Quadratic Dynamic Matrix Control of Isopropyl Acetate Reactive Distillation Column

The esterification of acetic acid with isopropanol is considered inside a RD column. The column has a total condenser and reboiler. The theoretical stages are numbered from top to bottom. The equations for 14 stages for the system and four-component system were solved in MATLAB by ODE45 solver. Dynamic model of reactive distillation column was developed assuming ideal trays and phase splitting in the decanter incorporating tray to tray mass and energy balance. A MATLAB® code was written for solving the resulting ordinary differential equations-initial value problems. The data defining the column configuration, feed composition, column holdup, etc. is given in Table I. This data corresponds to the steady state of RD Column at reflux ratio of 4.
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A dynamic analysis of tuberculosis dissemination to improve control and surveillance.

A dynamic analysis of tuberculosis dissemination to improve control and surveillance.

The method we have presented here is easily implemented and provides relevant information concerning the spatio-temporal propagation of TB using GIS data. In comparison to more traditional methods, our approach is novel for the following reasons. 1) Instead of showing high-risk regions, it precisely locates the main sources of infection in the high risk regions determined by the usual statistical approaches. 2) Different from the usual statistical approaches that filter and transform the raw data to generate risk or probability density functions, it allows to extract relevant information directly from the raw data, as for instance the movement of the etiological agent. Because of this, the technique presented here, unlike stationary ones [6,7], is not sensitive to the irregular distribution of CTs. 3) Since this method is based on the study of individual settings (a town or state) it avoids generalizations that might overlook the specificities of TB transmission in different communities and regions. 4) Finally, our method is not only descriptive but is also useful for evaluation purposes because the analysis of the case distribution after the implementation of any control strategy would provide informa- tion on the strategy’s efficiency. The changes could be evaluated by comparing a series of quantities, among them, the number of foci, the size (both in terms of the number of links and of the spatial area) of the largest connected cluster of neighbour CT’s with at least one new case per year, etc. In all cases, changes in these quantities should be compared during several years in order to discard fluctuations.
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Control of a robotic knee exoskeleton for assistance and rehabilitation based on motion intention from sEMG

Control of a robotic knee exoskeleton for assistance and rehabilitation based on motion intention from sEMG

The position of the reference electrode was on the right leg. A goniometer and a footswitch also were used on the right leg to obtain the knee angle and the gait phases during walking. The subjects were cued through visual and sound stimuli with a period of 10 s to execute the following motor tasks: Stand-Up/Sit-Down (SU/SD), knee Flexion/Extension (F/E), two steps in walking (W), and Rest Stand-Up/Sit-Down (RSU/RSD). The motor tasks performed were repeated into two di fferent experiments. Initially, a defined sequence composed of ten trials for each motor tasks was performed. Afterward, a random order, including six repeated trials for each motor task, was proposed to enhance generalization ability due to the fluctuation of sEMG. Each experiment had three tests of 20 trials (60 trials total), with rest of 3 min. The acquisition hardware was attached to a mobile platform in order to follow the subjects during the test. Thereafter, the sEMG data were processed o ff-line using Matlab  2014b. The HMIR system was validated for both lower-limb and trunk muscles. During the supervised learning, the classifiers were trained combining the first six trials from the sequential experiment with four
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Improvisation Based on Imitating Human Players by a Robotic Acoustic Musical Device

Improvisation Based on Imitating Human Players by a Robotic Acoustic Musical Device

Imitation of playing musical instruments and reproduction of acoustic music has been investigated in the well defined musical domain of jazz [1,2,3]. Research that focus on the presence of a single model which is always detectable in the scene and which is always performing the task that the observer is programmed to learn [4,5] has been made. Musical imitation have been handled in many studies, being facilitated through the use of computer generated music [6,7,8]. Various new electric musical instruments, including a wearable one and a PDA based one have been proposed [9,10,11]. A fixed- function mapping based imitation supporting system has also been proposed [12]. In our work, we concentrate upon imitating by ROMI to reproduce acoustic melodies from human teachers playing two types of instruments. In the next section, ROMI will be introduced together with its control architecture. In the third section, we will summarize our musical state representation that is used for controlling ROMI. The imitation process will be demonstrated by an example in the same section as well. Our proposed parameter estimation process will be presented and discussed in the fourth section. Section five concludes the paper.
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Improving the Performance of Adaptive PDPID Control of Two-Link Flexible Robotic Manipulator with ILC

Improving the Performance of Adaptive PDPID Control of Two-Link Flexible Robotic Manipulator with ILC

o remain competitive in today’s industry, high productivity and low cost of production are key amongst other things. The use of robot in manufacturing was phenomena as most robots are used to achieve work in the most hazardous environments where men may not survive, is one of the numerous advantages of robots. The traditional robots were made rigid and are very heavy, they consume more power and they are slow in operation [1], they have low payload to weight ratio because large payload cause them to sag [2], and so on . To overcome some of these problems, flexible link manipulators were developed which are lighter in weight, consume less power, have faster manipulation, higher payload to weight ratio, require less material etc [3]. With all these advantages, to control such a flexible system comes with a lot of difficulties because of the high distributed nature of such a system [4]. Proportional Integral Derivative
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Automatic Landing Control Design for Unmanned Aerial Vehicles

Automatic Landing Control Design for Unmanned Aerial Vehicles

Kalman filter is used in the system. For this purpose a small UAV that is normally used as a radio controlled plane is chosen. The linearized equations for a wings level flight condition and the state space matrices are derived. An optimal controller using LQR method to control the altitude level is then designed. The effect of the disturbances on the measurements are taken into account and the effectiveness of the Kalman filter in obtaining the correct measurements and achieving the desired control level are shown using the controller designed for the system. The small UAV is commanded to the desired altitude using the LQR controller through the control inputs elevator deflection and thrust rate. The LQR effectiveness matrices are chosen to find the gains necessary to build an effective altitude controller. Firstly the controller is tested under the situation where disturbances are absent. Then a Kalman filter is designed and the system under disturbances is tested with the designed controller and the filter. The results reveal the effectiveness of the Kalman filter and the LQR controller.
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Structural control of ecological and biological networks

Structural control of ecological and biological networks

structural control of any kind of ecological and biological network. The rationale behind Structural ENC is that during field experiments and manipulations it could result difficult to quantitatively control stocks and flows in order to drive the ecological or biological network towards the desired state. In these cases, similar results can be achieved using a more parsimonious approach based on the inhibition of one or several nodes and/or edges. Although network control through the inhibition of one or several nodes and/or edges is a kind of structural control that acts impolitely if compared to the functional control previously used by ENC, it is more parsimonious from a feasibility (i.e. in situ application) viewpoint, hence in some cases it could be the most feasible solution for the control of the real networks.
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Hippocampal neurons keep track of two things--one moving, one not--simultaneously.

Hippocampal neurons keep track of two things--one moving, one not--simultaneously.

Animals move, and because they do, they must be masters of multiple frames of reference. As the monkey vaults himself through the air, his eye must be on the stationary branch looming into view; as the child circles on the merry-go-round, her eye must track the brass ring just around the curve.

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Design And Implementation Of Smart Living Room Wireless Control For Safety Purpose

Design And Implementation Of Smart Living Room Wireless Control For Safety Purpose

Microcontroller based living room control system using Bluetooth technology will provide effective and modernized living standard.Bluetooth is a wireless technology standard for exchanging data over short distances (using short wavelength UHF radio waves in the ISM band from 2.4 to 2.485 GHz) from fixed and mobile devices, and building personal area networks (PANs). Living room control system from mobile is one of the most popular forms of wireless control technology. Researchers around the world are continuously improving our life by creating innovative applications of computing for our daily activities. Today, mobile phones come out of work place and are effectively used to communicate and to make our life easier and better than ever. In this living room control system, they are used to control the living room appliances via Bluetooth technology. Being inspired by the widespread use of wireless communication technology, we are proposing a concept of Smart Living Room System that will make our home convenient and smart. In this research,the door of the living room opens and closes by using keypad lock system. It is controlled by arduino controller and the status of the door is displayed on serial LCD. The control of light bulbs, fan speed, dim light and window angle based on wireless Bluetooth technology and microcontrollerare implemented. Users of the living room can interact with the devices by wireless mobile interface via Bluetooth. This system also requires a specialized android apk to control the living room appliances from mobile. Implementation of Smart Living Room system has several advantages. Door security system was built with a keypad that was controlled by arduino. To open the door, user must enter the correct password and if the wrong password was entered, the door will be still locked. It can save the home from entering thieves and strangers.Old and disable persons can manage the living room without using too much effort. As fan speed can be adjusted, users can maintain the room temperature as the desire. User can also vary the lighting of the room by using dim light. There isalso a window system that can be opened and closed between 0 and 180 degree as user desire.Furthermore, four light bulbs are also presented and user can switch on and offthem. All the appliances in the living room can be controlled without using too much energy. It can be controlled easily by mobile from any place of the room. While user can’t go to open or close the
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Sediment sampling in estuarine mudflats with an aerial-ground robotic team

Sediment sampling in estuarine mudflats with an aerial-ground robotic team

At each moment, the system must gather sensory feedback about the robot’s pose and its surroundings. This sensory feedback comes asynchronously and, therefore, must be associated with a time stamp. ROS provides this functionality. Based on the sensory feedback provided by the wheel odometers, by the GPS-RTK device and by the inertial measurement unit, an Extended Kalman Filter (EKF) recursively estimates the UGV’s optimal pose. Due to the absence of tall buildings or trees in estuarine environments, the GPS-RTK device is capable of producing centimeter-level global localization accuracy alone, in most situations. Nevertheless, wheel odometry helps the EKF to filter out GPS-RTK spurious noise and signal drop-outs. To mitigate motion estimate errors resulting from wheel slippage or blockage, we estimate the motion of the robot using each wheel independently and then fuse the four estimates in a weighted manner. The more similar the motion estimated from one of the wheels is from the estimates obtained from the other three wheels, the higher is its weight in the fusion process. This process exploits the redundancy introduced by the four wheels to disregard deviating motion estimates. Please refer to [41] for further details.
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Non-Linear Dynamic Deformation of a Piezothermoelastic  Laminate with Feedback Control System

Non-Linear Dynamic Deformation of a Piezothermoelastic Laminate with Feedback Control System

We study the control of free vibration with large amplitude in a piezothermoelastic laminated beam subjected to a uniform temperature with a feedback control system. The analytical model is the symmetrically cross-ply laminated beam composed of the elastic and piezoelectric layers. On the basis of the von Kármán strain and the classical laminate theory, the governing equations for the dynamic behavior are derived. The dynamic behavior is detected by the electric current in the sensor layer through the direct piezoelectric effect. The electric voltage with the magnitude of the current multiplied by the gain is applied to the actuator layer to constitute a feedback control system. The governing equations are reduced by the Galerkin method to a Liénard equation with respect to the representative deflection, and the equation is found to be dependent on the gain and the configuration of the actuator. By introducing the Liénard's phase plane, the equation is analyzed geometrically, and the essential characteristics of the beam and stabilization of the dynamic deformation are demonstrated.
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Influence of the robotic exoskeleton Lokomat on the control of human gait: an electromyographic and kinematic analysis

Influence of the robotic exoskeleton Lokomat on the control of human gait: an electromyographic and kinematic analysis

Hidler, J. et al [36] have been studying the differences of muscular activation in lower limb muscles during treadmill walking and Lokomat-assisted walking, using 100% of guid- ance force in Lokomat walking of healthy subjects. His group referred that there are differ- ences of activation patterns between both types of walking, mainly because Lokomat limits the degrees of freedom of legs and pelvis. Among those differences, it can be mentioned, for example, that quadriceps (Rectus femoris and vastus lateralis) and hamstrings presented higher activity during the swing phase of Lokomat walking than treadmill walking, whereas tibialis anterior and gastrocnemius presented reduced activity along most of the gait cycle in Lokomat (see figure 5.10). In relation to the gastrocnemius and tibialis anterior activity during Lokomat walking, the authors reported that the drop in muscle activity can be related with the use of footlifters, which assist ankle dorsiflexion for toe clearance during swing phase [36]. In relation to the quadriceps, the explanation can be the fact that people usually rotate their hips and also abduct their legs to allow the toe to clear the floor, which are move- ments quite limited to perform in Lokomat. Therefore, people exert higher muscle activity in the quadriceps to help in the elevation of the feet and preventing toe from getting caught in the treadmill [36].
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New Strategy for Congestion Control based on Dynamic Adjustment of Congestion Window

New Strategy for Congestion Control based on Dynamic Adjustment of Congestion Window

TCP SACK (TCP with Selective Acknowledgement) is an extension of the TCP Reno. It only modifies the fast recovery algorithm of Reno keeping the other algorithms unchanged [8]. Similar to NewReno, TCP SACK handles multiple packet losses from the same window but it has a better estimation capability for the number of outstanding packets. In SACK, instead of cumulative acknowledgement of packets as contained in Tahoe, Reno and NewReno, packets are acknowledged selectively. Where, the receiver can inform the sender about all packets that have arrived successfully. This enables the sender to figure out which packets have been acknowledged and which ones are still outstanding. So, the sender need retransmit only the packets that have actually been lost without needing to retransmit packets that have already been received successfully. To keep track of the acknowledged and lost packets, the sender maintains a data structure called scoreboard. Whenever the sender is allowed to transmit, it consults the scoreboard and transmits the missing packets. If there is no missing packet to retransmit, it transmits new packets. When a retransmitted packet is dropped, the sender detects it by a retransmit timeout. In case of timeout, it retransmits the packet and enters into the slow start phase. One major drawback of the TCP SACK is the relative difficulty in implementation of selective acknowledgement [23].
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Motion Control Design for Robotic Walking Support Systems Using Admittance Motion Command Generator

Motion Control Design for Robotic Walking Support Systems Using Admittance Motion Command Generator

further, the PAM-AID mobile robot [2], consisting of a walking frame with wheels, was developed to help avoid obstacles and physically support a person while walking. To help the elderly live independently in private living environments, a robotic assistant called Care-O-Bot II [3][4] was developed with adjustable walking supports to support and guide elderly people safely in indoor environments. Hirata et al. [5][6] proposed a passive intelligent walker, called the RT Walker, to assist elderly and handicapped people to walk in both indoor and outdoor environments. The developed adaptive motion control algorithm enables the RT Walker to adapt to user operation, and the walker helps avoid obstacles on the basis of extracted environmental information. Chuy Jr. et al. [7][8][9] developed the Walking Helper; this device considers user operation characteristics to aid users in controlling their walking support system. Further, Chuy Jr. et al. [10] developed a motorized robotic walking support system based on the passive behavior concept proposed by Hirata et al. [5] to enhance interaction between the walking support system and the user. Wasson et al. [11] presented an operation system that can determine a user’s navigational intent by measuring the forces and moments acting on the handles of the walker. Morris et al. [12] proposed a robotic walker that integrates a haptic interface and a robot localization and navigation system to provide mobility assistance to frail elderly people with cognitive impairment. Sabatini et al. [13] developed a motorized rollator equipped with force, ultrasonic, and infrared sensors to support elderly people and avoid collisions while walking. Chugo et al. [14] developed a robotic walker system that combines standing and walking assistance functions by using an assistance manipulator and an active walker to provide standing, walking, and seating assistance for the elderly. Spenko et al. [15] developed a smart walker that provides support, guidance, and health monitoring for the elderly in an assisted living facility. This smart walker uses a six-axis force/torque sensor attached to the walker’s handle as the main control input interface. Furthermore, a shared adaptive control algorithm was developed to control the smart walker by a computer controller, allowing the smart walker to gently guide the user. Spenko et al. [15] also developed a smart cane that provides functions similar to those of the smart walker. Although some cane robots such as the Walking Guide Robot [16], RoJi Robot [17], GuideCane Robot [18], and the Robotic Cane proposed by Aigner and McCarragher [19] can provide good guiding performances for the visually impaired and the elderly, they cannot physically support the elderly during walking.
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A Nervousness Regulator Framework for Dynamic Hybrid Control Architectures

A Nervousness Regulator Framework for Dynamic Hybrid Control Architectures

FMS Controlled system: the general structure of the FMS is divided into two layers: a global and a local layer. While the global layer contains a unique global decisional entity (GDE) responsible for optimizing the release sequence of the production orders (scheduler), the local layer contains several local decisional entities (LDE) as jobs to be processed in the production order (7 jobs in scenario A0). In this approach, each decisional entity (GDE or LDE) includes its own objective and governance parameters. In this scenario, the objectives of the GDE and LDE are respectively to minimize the makespan at batch execution level and the completion of the next operation. The governance parameter in the GDE is the role of the entity for establishing the order release sequence and imposing these intentions to the LDE in the shop floor. The governance of each LDE is represented by the reactive technique that guides the evolution of the job through the shop floor. This evolution can be driven by a potential-field’s (PF) approach [12] or by the first available machine rule (FAM). For this research, even though both PF and FAM techniques are part of the reactive approach in distributed systems, it is considered that the potential-field’s approach assures higher performances while computing resource allocation depending on their availability and shortest route to the resources. For a better representation of the configuration, an operating mode vector that gathers all the governance parameters of the decisional entities is defined.
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DYNAMIC CONGESTION CONTROL IN WDM OPTICAL NETWORK

DYNAMIC CONGESTION CONTROL IN WDM OPTICAL NETWORK

In this work, however, we have considered only the wavelength routed networks. Nonetheless, the promising future of WDM networks makes them an interesting topic for the research. The objective was to search for a way to reduce the node congestion in a heavy busty traffic in the area of optical networking. Because of the large amount of activity on this subject over the past dozen years, capturing the important and most significant developments in a concise format is a challenging task; thus, apologize if we inadvertently left out some contributions which could be considered to be more important. We have introduced a backward reservation protocol and implemented a solution to control the congestion in WDM network by lowering the blocking probability. This is accomplished by allowing the nodes that are considered to be the main decision points for selecting the shortest path and also try another shortest path if the first choice does not succeed.
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