scholarly journals Admittance control for physical human–robot interaction

2018 ◽  
Vol 37 (11) ◽  
pp. 1421-1444 ◽  
Author(s):  
Arvid QL Keemink ◽  
Herman van der Kooij ◽  
Arno HA Stienen
Keyword(s):  
High Performance ◽  
Controller Design ◽  
Design Guidelines ◽  
Human Robot Interaction ◽  
Physical Interaction ◽  
Admittance Control ◽  
Interaction Control ◽  
Force Signal ◽  
And Performance ◽  
The Stability

This paper presents an overview of admittance control as a method of physical interaction control between machines and humans. We present an admittance controller framework and elaborate control scheme that can be used for controller design and development. Within this framework, we analyze the influence of feed-forward control, post-sensor inertia compensation, force signal filtering, additional phase lead on the motion reference, internal robot flexibility, which also relates to series elastic control, motion loop bandwidth, and the addition of virtual damping on the stability, passivity, and performance of minimal inertia rendering admittance control. We present seven design guidelines for achieving high-performance admittance controlled devices that can render low inertia, while aspiring coupled stability and proper disturbance rejection.

scholarly journals A variable admittance control strategy for stable physical human–robot interaction

2019 ◽  
Vol 38 (6) ◽  
pp. 747-765 ◽  
Author(s):  
Federica Ferraguti ◽  
Chiara Talignani Landi ◽  
Lorenzo Sabattini ◽  
Marcello Bonfè ◽  
Cesare Fantuzzi ◽  
...  
Keyword(s):  
Human Robot Interaction ◽  
Admittance Control ◽  
Robot Interaction ◽  
Interaction Control ◽  
Human Arm ◽  
Industrial Operations ◽  
Novel Method ◽  
The Stability ◽  
Stability Issues ◽  
Human Robot Collaboration

Admittance control allows a desired dynamic behavior to be reproduced on a non-backdrivable manipulator and it has been widely used for interaction control and, in particular, for human–robot collaboration. Nevertheless, stability problems arise when the environment (e.g. the human) the robot is interacting with becomes too stiff. In this paper, we investigate the stability issues related to a change of stiffness of the human arm during the interaction with an admittance-controlled robot. We propose a novel method for detecting the rise of instability and a passivity-preserving strategy for restoring a stable behavior. The results of the paper are validated on two robotic setups and with 50 users performing two tasks that emulate industrial operations.

scholarly journals Calibrating intuitive and natural human–robot interaction and performance for power-assisted heavy object manipulation using cognition-based intelligent admittance control schemes

2018 ◽  
Vol 15 (4) ◽  
pp. 172988141877319 ◽  
Author(s):  
S M Mizanoor Rahman ◽  
Ryojun Ikeura
Keyword(s):  
Predictive Control ◽  
Optimization Algorithm ◽  
Weight Perception ◽  
Robotic System ◽  
Human Robot Interaction ◽  
Admittance Control ◽  
Robot Interaction ◽  
Heavy Object ◽  
Control Scheme ◽  
And Performance

In the first step, a one degree of freedom power assist robotic system is developed for lifting lightweight objects. Dynamics for human–robot co-manipulation is derived that includes human cognition, for example, weight perception. A novel admittance control scheme is derived using the weight perception–based dynamics. Human subjects lift a small-sized, lightweight object with the power assist robotic system. Human–robot interaction and system characteristics are analyzed. A comprehensive scheme is developed to evaluate the human–robot interaction and performance, and a constrained optimization algorithm is developed to determine the optimum human–robot interaction and performance. The results show that the inclusion of weight perception in the control helps achieve optimum human–robot interaction and performance for a set of hard constraints. In the second step, the same optimization algorithm and control scheme are used for lifting a heavy object with a multi-degree of freedom power assist robotic system. The results show that the human–robot interaction and performance for lifting the heavy object are not as good as that for lifting the lightweight object. Then, weight perception–based intelligent controls in the forms of model predictive control and vision-based variable admittance control are applied for lifting the heavy object. The results show that the intelligent controls enhance human–robot interaction and performance, help achieve optimum human–robot interaction and performance for a set of soft constraints, and produce similar human–robot interaction and performance as obtained for lifting the lightweight object. The human–robot interaction and performance for lifting the heavy object with power assist are treated as intuitive and natural because these are calibrated with those for lifting the lightweight object. The results also show that the variable admittance control outperforms the model predictive control. We also propose a method to adjust the variable admittance control for three degrees of freedom translational manipulation of heavy objects based on human intent recognition. The results are useful for developing controls of human friendly, high performance power assist robotic systems for heavy object manipulation in industries.

scholarly journals Energy Efficient SRAM

2019 ◽  
Vol 8 (9) ◽  
pp. 1086-1091
Keyword(s):  
Power Consumption ◽  
High Performance ◽  
Dynamic Logic ◽  
Cmos Technology ◽  
Digital Circuit ◽  
Static Noise Margin ◽  
Noise Margin ◽  
And Performance ◽  
The Stability ◽  
Static Noise

Memories are an essential unit of any digital circuit, thus their power consumption must be considered during the designing process of the cells. To improve performance, reduce delay and increase stability, it is advisable to decrease the power consumed by the memory. Due to high demand of speed, high performance, there’s a need to decrease the size of the device, thereby increasing the devices placed per chip. This high integration makes chips more complex but improves device performance. Design of SRAM cells with speed and low power is crucial so as to replace DRAMs. The layout of SRAM has advanced to meet the requirements of the present industry in accordance with parameters like delay, power consumption and stability etc. This paper presents the aim of analyzing different technologies used to make SRAM more efficient in terms of parameters such as static noise margin, latency and dissipation of power. The stability investigation of SRAM cells are usually derived from the Static Noise Margin (SNM) analysis. Here we observe a SRAM design which has used dynamic logic and pass transistor logic. We further study the effects made on this design by employing various technologies such as AVL-S, AVL-G, AVL and MT-CMOS, at 180nm CMOS technology to achieve enhancements in delay, power consumption and performance. The proposed circuits are simulated and the results obtained have been analyzed to show significant improvement over conventional SRAM designs. Cadence Virtuoso simulation is used to confirm all the results obtained in this paper for the simulation of 180 nm CMOS technology SRAMs.

scholarly journals Flight and Interaction Control of an Innovative Ducted Fan Aerial Manipulator

Sensors ◽  
2020 ◽  
Vol 20 (11) ◽  
pp. 3019
Author(s):  
Yibo Zhang ◽  
Bin Xu ◽  
Changle Xiang ◽  
Wei Fan ◽  
Tianfu Ai
Keyword(s):  
Controller Design ◽  
Experimental Tests ◽  
Adaptive Controller ◽  
Physical Contact ◽  
Physical Interaction ◽  
The Novel ◽  
Interaction Control ◽  
Ducted Fan ◽  
Aerial Manipulator ◽  
Confined Environment

An innovative aerial manipulator with ducted fans is proposed to achieve side-on aerial manipulation tasks in a confined environment, such as canopy sampling in dense forests. The dynamic model of the novel design is studied, and on this basis a composite controller is proposed to address the challenges of arm extension and physical interaction during the manipulation process. An adaptive controller is proposed for the aerial platform to achieve good stability and tracking performance under the manipulator motion, and an impedance controller is designed for the manipulator to ensure compliance and stability during physical contact. The experimental tests validate the effectiveness of the proposed prototype structure and controller design.

Tracking Control of Robot Manipulator Using Sliding Mode Controller With Performance Robustness

1999 ◽  
Vol 121 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Chieh-Li Chen ◽  
Rui-Lin Xu
Keyword(s):  
Tracking Control ◽  
Feedback Linearization ◽  
Controller Design ◽  
Sliding Mode ◽  
Robot Manipulator ◽  
Design Procedure ◽  
Sliding Mode Controller ◽  
Systematic Design ◽  
And Performance ◽  
The Stability

The tracking control problem of robot manipulator is considered in this paper. A sliding mode controller design with global invariance is proposed using the concept of extended system and feedback linearization. The sliding surface is assigned such that the sliding mode motion will occur while the proposed control law is applied. This results in a system with global invariance. The stability and performance of the resulting system can be guaranteed by the proposed systematic design procedure.

Robust Controller Design to Achieve Active Damping for a MEMS Microphone

2008 ◽  
Author(s):  
Jinli Qu ◽  
Ronald N. Miles ◽  
N. Eva Wu
Keyword(s):  
Closed Loop ◽  
Controller Design ◽  
Active Damping ◽  
Closed Loop System ◽  
Robust Controller ◽  
Nonlinear Simulation ◽  
Mems Microphone ◽  
And Performance ◽  
The Stability ◽  
Robust Controller Design

This paper presented an H∞-controller design to achieve active damping for a MEMS microphone system. The parametric uncertainties introduced by linearization process were modeled. The stability and performance of the closed-loop system were analyzed for the uncertain microphone model and both were shown to be robust. The nonlinear simulation further verifies that the controller offers the desired performance.

DESIGN, CONTROL AND EVALUATION OF A WHOLE-SENSITIVE ROBOT ARM FOR PHYSICAL HUMAN-ROBOT INTERACTION

2009 ◽  
Vol 06 (04) ◽  
pp. 699-725 ◽  
Author(s):  
DZMITRY TSETSERUKOU ◽  
NAOKI KAWAKAMI ◽  
SUSUMU TACHI
Keyword(s):  
High Performance ◽  
Design Procedure ◽  
Human Robot Interaction ◽  
Experimental Results ◽  
Physical Interaction ◽  
Robot Arm ◽  
Robot Interaction ◽  
Active Compliance ◽  
And Control ◽  
Damping Of Vibrations

The paper focuses on design and control of a new anthropomorphic robot arm enabling the torque measurement in each joint to ensure safety while performing tasks of physical interaction with human and environment. When the contact of the robot arm with an object occurs, local admittance algorithm provides active compliance of corresponding robot arm joint. Thus, the whole structure of the manipulator can safely interact with an unstructured environment. The detailed design procedure of the 4-DOF robot arm and optical torque sensors is described in the paper. The experimental results of joint admittance control revealed the feasibility of the proposed approach to provide safe interaction of entire structure of robot arm with a person. The control system with load angle position feedback and lead compensator is proposed to improve dynamic behavior of flexible joint arm. The experimental results show high performance of the developed controller in terms of successful damping of vibrations.

scholarly journals Discrete-time control of bilateral teleoperation systems: a review

Robotica ◽  
2017 ◽  
Vol 36 (4) ◽  
pp. 552-569 ◽  
Author(s):  
Amir Aminzadeh Ghavifekr ◽  
Amir Rikhtehgar Ghiasi ◽  
Mohammad Ali Badamchizadeh
Keyword(s):  
Communication Networks ◽  
Discrete Time ◽  
Continuous Time ◽  
Controller Design ◽  
Design Guidelines ◽  
Bilateral Teleoperation ◽  
Transmission Delays ◽  
Time Control ◽  
The Stability ◽  
Teleoperation Systems

SUMMARYThe possibility of operating in remote environments using teleoperation systems has been considered widely in the control literature. This paper presents a review on the discrete-time teleoperation systems, including issues such as stability, passivity and time delays. Using discrete-time methods for a master-slave teleoperation system can simplify control implementation. Varieties of control schemes have been proposed for these systems and major concerns such as passivity, stability and transparency have been studied. Recently, unreliable communication networks affected by packet loss and variable transmission delays have been received much attention. Thus, it is worth considering discrete-time theories for bilateral teleoperation architectures, which are formulated on the same lines as the continuous-time systems. Despite the extensive amount of researches concerning continuous-time teleoperation systems, only a few papers have been published on the analysis and controller design for discrete bilateral forms. This paper takes into account the challenges for the discrete structure of bilateral teleoperation systems and notifies the recent contributions in this area. The effect of sampling time on the stability-transparency trade-off and the task performance is taken into consideration in this review. These studies can help to design guidelines to have better transparency and stable teleoperation systems.

The Robust Control of Magnetic Bearings for Rotating Machinery

2006 ◽  
Vol 113 ◽  
pp. 125-130 ◽  
Author(s):  
Zdzisław Gosiewski ◽  
Arkadiusz Mystkowski
Keyword(s):  
Robust Control ◽  
Controller Design ◽  
Magnetic Suspension ◽  
Magnetic Bearings ◽  
Weight Functions ◽  
H2 Control ◽  
Uncertainty Model ◽  
Energy Limitation ◽  
And Performance ◽  
The Stability

The fast progress in the applications of active magnetic suspension systems needs to apply the modern control theory. This paper deals with H∞ and H2 control of rigid rotor movement, which is supported in magnetic bearings. The robust control of magnetic bearings is investigated analytically. The nominal model of active magnetic suspension of rotor and the uncertainty model were derived. The standard PID control and robust control are compared and performance of nominal feedback configuration with weights is presented. We propose a robust control with a multi-objective controller to achieve good robust stability when the model of a plant is uncertain. The behavior of multiplicative uncertainty of magnetic suspension system is shown. The aim of optimal robust control is to improve the magnetic suspension taking into account the energy limitation (i.e., to avoid the saturation of actuators). The H2 performance and H∞ performance depend on a proper selection of weighting functions. So a very important step in the controller design process is to choose the appropriate weight functions: We, Wu, Wd. The influence of noise is limited by weight functions. We also put limits on input and output signals. The stability of a system with disturbance interaction is discussed. The simulations of a well-posed and internally stable magnetic system are presented. The success of the robust control is demonstrated through results of numerical simulations.

Modeling and Simulation about the Web Running of the Web-Fed Printing Press System Based on Rigid Coupling

2012 ◽  
Vol 248 ◽  
pp. 462-468
Author(s):  
Lei Zhang ◽  
Yi Ming Wang ◽  
Shu Qin Wu ◽  
Jian Guo Li ◽  
Ming Ming Zhao
Keyword(s):  
High Performance ◽  
Physical Simulation ◽  
Tension Control ◽  
Load Testing ◽  
Key Factors ◽  
Printing Quality ◽  
And Performance ◽  
The Stability ◽  
Movement Rules ◽  
The Web

The stability and performance of the web running is one of the key factors of printing quality. Through the analysis of the mechanical structure of web running, movement rules and dynamic characteristics of the tape established the physical simulation model. A physical simuliation platform of the web-fed system was built based on technical load testing about feeding device, the feed rollers and tension control, a guidance for optimizing the structure, designing of high-performance presses on the basis of the experiment and web running was provided.

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