scholarly journals DYNAMIC COMPUTATION OF HAPTIC-ROBOT DEVICES FOR CONTROL OF A SURGICAL TRAINING SYSTEM

2018 ◽  
pp. 81-93 ◽  
Author(s):  
Vu Minh Hung ◽  
Viorel Mihai ◽  
Cristian Dragana ◽  
Ion Ion ◽  
Nicolae Paraschiv
Keyword(s):  
Closed Loop ◽  
Control Model ◽  
Training System ◽  
Haptic Device ◽  
Dynamic Compensation ◽  
End Effector ◽  
Teleoperation System ◽  
Dynamic Computation ◽  
Force Tracking ◽  
Serial Robot

This paper presents a new control model of the haptic device for the closed loop teleoperation of a minimal surgery training system. Dynamics of a 6-DOF parallel haptic device is computed and compensated to make a decoupled linearization control model. In teleoperation system, the master is the 6-DOF haptic device and the slave is the 6-DOF serial robot. The master haptic device provides the trajectories for the slave serial robot through the operation of user’s hand on the steering handle while the slave robot sends feedback forces on its end effector to the master controller in order to generate forces/moments on the steering handle of haptic master. In this manner the user’s hand will feel the forces/moments as the same those of the robot end effector. The feeling force tracking performances of system can be improved by using dynamic compensation and decoupled linearization controller based on fuzzy PID algorithms. Experiment results indicate that the dynamic compensation and fuzzy control can improve the control performances effectively.

Parameterization of Three-Dimensional Rigid Body Guidance Incorporating Planar Gear Connections in a Spatial Closed-Loop Mechanism With Parallel Consecutive Axes

2008 ◽  
Author(s):  
Javier Rolda´n Mckinley ◽  
Carl Crane ◽  
David B. Dooner
Keyword(s):  
Computer Animation ◽  
Closed Loop ◽  
Three Dimensional ◽  
Motion Generation ◽  
Repetitive Motion ◽  
End Effector ◽  
Spatial Mechanism ◽  
Joint Axis ◽  
Position And Orientation ◽  
Six Degree Of Freedom

This paper introduces a reconfigurable closed-loop spatial mechanism that can be applied to repetitive motion tasks. The concept is to incorporate five pairs of non-circular gears into a six degree-of–freedom closed-loop spatial chain. The gear pairs are designed based on given mechanism parameters and a user defined motion specification of a coupler link of the mechanism. It is shown in the paper that planar gear pairs can be used if the spatial closed-loop chain is comprised of six pairs of parallel joint axes, i.e. the first joint axis is parallel to the second, the third is parallel to the fourth, ..., and the eleventh is parallel to the twelfth. This paper presents the synthesis of the gear pairs that satisfy a specified three-dimensional position and orientation need. Numerical approximations were used in the synthesis the non-circular gear pairs by introducing an auxiliary monotonic parameter associated to each end-effector position to parameterize the motion needs. The findings are supported by a computer animation. No previous known literature incorporates planar non-circular gears to fulfill spatial motion generation needs.

Force Capabilities of Two-Degree-of-Freedom Serial Robots Equipped With Passive Isotropic Force Limiters

2015 ◽  
Author(s):  
Meiying Zhang ◽  
Thierry Laliberté ◽  
Clément Gosselin
Keyword(s):  
Human Robot Interaction ◽  
Contact Forces ◽  
Degree Of Freedom ◽  
Practical Implementation ◽  
Robot Interaction ◽  
End Effector ◽  
Serial Robots ◽  
Serial Robot ◽  
Maximum Contact ◽  
Two Degree Of Freedom

This paper proposes the use of passive force and torque limiting devices to bound the maximum forces that can be applied at the end-effector or along the links of a robot, thereby ensuring the safety of human-robot interaction. Planar isotropic force limiting modules are proposed and used to analyze the force capabilities of a two-degree-of-freedom planar serial robot. The force capabilities at the end-effector are first analyzed. It is shown that, using isotropic force limiting modules, the performance to safety index remains excellent for all configurations of the robot. The maximum contact forces along the links of the robot are then analyzed. Force and torque limiters are distributed along the structure of the robot in order to ensure that the forces applied at any point of contact along the links are bounded. A power analysis is then presented in order to support the results. Finally, examples of mechanical designs of force/torque limiters are shown to illustrate a possible practical implementation of the concept.

Industrial compliant robot bases in interaction tasks: a force tracking algorithm with coupled dynamics compensation

Robotica ◽  
2016 ◽  
Vol 35 (8) ◽  
pp. 1732-1746 ◽  
Author(s):  
Loris Roveda ◽  
Nicola Pedrocchi ◽  
Federico Vicentini ◽  
Lorenzo Molinari Tosatti
Keyword(s):  
Closed Loop ◽  
Control Law ◽  
Light Weight ◽  
Mobile Platforms ◽  
Control Laws ◽  
Assembly Task ◽  
Base Position ◽  
Force Tracking ◽  
Compliant Robot ◽  
Target Force

SUMMARYLight-weight manipulators are used in industrial tasks mounted on mobile platforms to improve flexibility. However, such mountings introduce compliance affecting the tasks. This work deals with such scenarios by designing a controller that also takes into account compliant environments. The controller allows the tracking of a target force using the estimation of the environment stiffness (EKF) and the estimation of the base position (KF), compensating the robot base deformation. The closed-loop stability has been analyzed. Observers and the control law have been validated in experiments. An assembly task is considered with a standard industrial non-actuated mobile platform. Control laws with and without base compensation are compared.

scholarly journals Development of Wireless Sensor Device for Machine English Oral Pronunciation Noise Detection

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yaning Zhu
Keyword(s):  
Closed Loop ◽  
Detection Algorithm ◽  
Training System ◽  
Circuit Board ◽  
Wireless Sensor ◽  
Noise Detection ◽  
Traditional System ◽  
Spoken English ◽  
Loop Design ◽  
Detection Technology

There is often noise in spoken machine English, which affects the accuracy of pronunciation. Therefore, how to accurately detect the noise in machine English spoken language and give standard spoken pronunciation is very important and meaningful. The traditional machine-oriented spoken English speech noise detection technology is limited to the improvement of software algorithm, mainly including speech enhancement technology and speech endpoint detection technology. Based on this, this paper will develop a wireless sensor network based on machine English oral pronunciation noise based on air and nonair conduction, reasonably design and configure air sensors, and nonair conduction sensors to deal with machine English oral pronunciation noise, so as to improve the naturalness and intelligibility of machine English speech. At the hardware level, this paper mainly optimizes the AD sampling, sensor matching layout, and internal hardware circuit board layout of the two types of sensors, so as to solve the compatibility problem between them and further reduce the hardware power consumption. In order to further verify or evaluate the performance of the machine spoken English speech noise detection sensor designed in this paper, a machine spoken English training system based on Android platform is designed. Compared with the traditional system, the training system can improve the intelligence of machine oriented oral English noise detection algorithm, so as to continuously improve the accuracy of system detection. The machine English pronunciation is adjusted and corrected by combining the data sensed by the sensor, so as to form a closed-loop design. The experimental results show that the wireless sensor sample proposed in this paper has obvious advantages in detecting the accuracy of machine English oral pronunciation, and its good closed-loop system is helpful to further improve the accuracy of machine English oral pronunciation.

scholarly journals Automated Axis Alignment for a Nanomanipulator inside SEM and Its Error Optimization

Scanning ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Chao Zhou ◽  
Lu Deng ◽  
Long Cheng ◽  
Zhiqiang Cao ◽  
Shuo Wang ◽  
...  
Keyword(s):  
Average Method ◽  
Closed Loop ◽  
Alignment Method ◽  
Visual Servo ◽  
End Effector ◽  
Axis Alignment ◽  
Deposition Effect ◽  
Relationship Of ◽  
The Relationship ◽  
Error Optimization

In the motion of probing nanostructures, repeating position and movement is frequently happing and tolerance for position error is stringent. The consistency between the axis of manipulators and image is very significant since the visual servo is the most important tool in the automated manipulation. This paper proposed an automated axis alignment method for a nanomanipulator inside the SEM by recognizing the position of a closed-loop controlling the end-effector, which can characterize the relationship of these two axes, and then the rotation matrix can be calculated accordingly. The error of this method and its transfer function are also calculated to compare the iteration method and average method. The method in this paper can accelerate the process of axis alignment to avoid the electron beam induced deposition effect on the end tips. Experiment demonstration shows that it can achieve a 0.1-degree precision in 90 seconds.

Upper limb robot-assisted therapy in subacute and chronic stroke patients using an innovative end-effector haptic device: A pilot study

2018 ◽  
Vol 42 (1) ◽  
pp. 43-52 ◽  
Author(s):  
S. Mazzoleni ◽  
E. Battini ◽  
R. Crecchi ◽  
P. Dario ◽  
F. Posteraro
Keyword(s):  
Pilot Study ◽  
Upper Limb ◽  
Chronic Stroke ◽  
Haptic Device ◽  
Stroke Patients ◽  
Robot Assisted ◽  
End Effector

Research on Direct Tension Control of Underfeed Winder

2012 ◽  
Vol 203 ◽  
pp. 18-21
Author(s):  
Hui Fang ◽  
Wei Tang ◽  
Yan Jing Meng
Keyword(s):  
Load Distribution ◽  
Closed Loop ◽  
Pressure Control ◽  
Tension Control ◽  
Volume Control ◽  
Direct Tension ◽  
Dynamic Compensation ◽  
Compensation Control

The paper analyzes the method of direct tension control, provides repaired method of closed loop speed for tension control of underfeed winder, and designs the systematic hardware figuration and software to effectively meet the demands of different volume control. Furthermore, the problems including pressure control of pressing roller, load distribution control of two-drum winder, tension control of paper, and dynamic compensation control were analyzed and solved through the design of hardware and software of S7-300 PLC.

Micro/Macro or Link-Integrated Micro-actuator Manipulation—A Kinematics and Dynamics Perspective

2006 ◽  
Vol 129 (10) ◽  
pp. 1086-1093 ◽  
Author(s):  
J. Zhang ◽  
J. Rastegar
Keyword(s):  
Dynamic Response ◽  
Closed Loop ◽  
Robot Manipulator ◽  
Robot Manipulators ◽  
High Harmonic ◽  
Kinematics And Dynamics ◽  
Control Problems ◽  
End Effector ◽  
Micro Actuators ◽  
And Control

Smart (active) materials based actuators, hereinafter called micro-actuators, have been shown to be well suited for the elimination of high harmonics in joint and/or end-effector motions of robot manipulators and in the reduction of actuator dynamic response requirements. Low harmonic joint and end-effector motions, as well as low actuator dynamic response requirements, are essential for a robot manipulator to achieve high operating speed and precision with minimal vibration and control problems. Micro-actuators may be positioned at the end-effector to obtain a micro- and macro-robot manipulation configuration. Alternatively, micro-actuators may be integrated into the structure of the links to vary their kinematics parameters, such as their lengths during the motion. In this paper, the kinematics and dynamics consequences of each of the aforementioned alternative are studied for manipulators with serial and closed-loop chains. It is shown that for robot manipulators constructed with closed-loop chains, the high harmonic components of all joint motions can be eliminated only when micro-actuators are integrated into the structure of the closed-loop chain links. The latter configuration is also shown to have dynamics advantage over micro- and macro-manipulator configuration by reducing the potential vibration and control problems at high operating speeds. The conclusions reached in this study also apply to closed-loop chains of parallel and cooperating robot manipulators.

Robotic force control for deburring using an active end effector

Robotica ◽  
1989 ◽  
Vol 7 (4) ◽  
pp. 303-308 ◽  
Author(s):  
G. M. Bone ◽  
M. A. Elbestawi
Keyword(s):  
Control System ◽  
Force Control ◽  
Pid Controller ◽  
Closed Loop ◽  
Least Squares Method ◽  
Closed Loop Control ◽  
End Effector ◽  
Loop Control ◽  
Positioning Errors ◽  
Force Control System

SUMMARYAn active force control system for robotic deburring based on an active end effector is developed. The system utilizes a PUMA-560 six axis robot. The robot's structural dynamics, positioning errors, and the deburring cutting process are examined in detail. Based on ARMAX plant models identified using the least squares method, a discrete PID controller is designed and tested in real-time. The control system is shown to maintain the force within l N of the reference, and reduce chamfer depth errors to 0.12 mm from the 1 mm possible without closed-loop control.

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