A robust high-speed position control scheme based on computed torque method for 2 DOF flexible link robot arms

2013 ◽  
Vol 5 (1) ◽  
pp. 27 ◽  
Author(s):  
K. Itamiya ◽  
M. Sawada
Keyword(s):  
High Speed ◽  
Position Control ◽  
Flexible Link ◽  
Robot Arms ◽  
Control Scheme ◽  
Computed Torque

A genetic algorithm-based computed torque control for slider–crank mechanism in the ship’s propeller

2013 ◽  
Vol 228 (12) ◽  
pp. 2090-2099 ◽  
Author(s):  
Farsam Farzadpour ◽  
Hossein Faraji
Keyword(s):  
Genetic Algorithm ◽  
Position Control ◽  
Torque Control ◽  
Process Noise ◽  
Piston Cylinder ◽  
Computed Torque Control ◽  
Control Scheme ◽  
Crank Mechanism ◽  
Parameter Deviation ◽  
Computed Torque

A lot of endeavors regarding the development of slider–crank mechanism in the ship’s propeller have been made and continue to be investigated. This paper presents the position control of a slider–crank mechanism, which is driven by the piston cylinder actuator to adjust the blade pitch angle. An effective motion control strategy known as the computed torque control can ensure global asymptotic stability. However, it is essential for this control scheme to have a precise and accurate system model. Moreover, large amounts of changes in the output and even instability of process are caused by a small amount of measurement or process noise, when the derivative gain is sufficiently large. Accordingly, in order to compensate any parameter deviation and disturbances as well as minimizing errors, we have presented a genetic algorithm-based computed torque control system which adjusts the proportional-derivative gains. Computer simulations are performed which reveals that asymptotically stability is reached and it confirms the effectiveness and high tracking capability of the proposed control scheme.

Dynamic Conveyor Tracking Control of a Delta Robot

2016 ◽  
Vol 679 ◽  
pp. 43-48 ◽  
Author(s):  
Guo Ying Zhang ◽  
Guan Feng Liu ◽  
Xiao Bin Guo ◽  
Xie Yuan Lin
Keyword(s):  
High Speed ◽  
Vision System ◽  
Conveyor Belt ◽  
Torque Control ◽  
Tracking Problem ◽  
Control Scheme ◽  
Pick And Place ◽  
Time Position ◽  
Delta Robot ◽  
Computed Torque

For general dynamic pick and place tasks that the objects are transferred with high speed by the conveyor belt, the capability of a delta robot to track the traveling objects is very important for the efficiency. To meet the needs of precision and smooth control, a computed-torque control scheme for conveyor tracking is implemented in this paper. For higher efficiency and accuracy, computer vision system, encoder and conveyor belt region are incorporated into the control scheme. Dividing the conveyor belt into three regions, the robot is commanded to track, pick and give up according to the subregions. Conveyor belt is equipped with an encoder that provides the controller with real-time position and speed of the belt. Based upon those informations, the controller automatically compensates the end positions with respect to the belt to adjust for the position of the conveyor. Then, the conveyor tracking problem is converted to a subregional tracking problem.

Redundancy Compensation in Control of Multiple Arms

1991 ◽  
Author(s):  
Amir Shirkhodaie ◽  
A. H. Soni
Keyword(s):  
Control Strategy ◽  
Position Control ◽  
Rigid Object ◽  
Common Object ◽  
Object A ◽  
Robot Arms ◽  
Control Scheme ◽  
Reaction Forces ◽  
End Effectors ◽  
The Individual

Abstract During manipulation of an object grasped at N locations by end-effectors of N robots, relaxation of assumption on invariant grasping locations of end-effectors Is too realistic. When coordinating end-effectors take infinitesimal displacements at the contact grasping locations with a rigid object, a slippage occurs which undesirably induces some redundancy in closed form kinematics/dynamics formulation of the entire robotic system. Particularly, in force/position control of multiple coordinating robot arms such an affect produces Inevitable impulsive reaction forces/moments which need to be compensated for in global control strategy of the system. In this paper, we have presented a control strategy with a Dynamic Redundancy Compensator (DRC) for cartesian space control of the coordinating multiple robots manipulating a common object. The proposed control scheme embeds dynamics of the individual coordinating robot arms and dynamically is capable to compensate for the kinematic/dynamic redundancies while preserving optimum forces/torques distribution between the end-effectors of robot arms. The results of study has been demonstrated on control of two robot arms manipulating a common object through prescribed coordinated motions.

An expanded impedance control scheme for slosh-free liquid transfer by a dual-arm cooperative robot

2020 ◽  
pp. 107754632096620
Author(s):  
Babak Naseri Soufiani ◽  
Mehmet Arif Adli
Keyword(s):  
High Speed ◽  
Control Method ◽  
Impedance Control ◽  
Kinematic Chain ◽  
Cylindrical Container ◽  
Robot Arms ◽  
Control Scheme ◽  
Liquid Transfer ◽  
Dual Arm ◽  
Multi Robot

The use of robots has been rapidly spreading in different daily applications. The transport of liquids by robot arms without causing any slosh is one of such applications which has recently taken the attention of researchers. Liquid transfer by dual-arm robots causes challenging problems because, in the process of dual-arm cooperation, a closed kinematic chain is formed and a set of constraints appears in motion, which increases the complexity of the process. In this study, an expanded impedance control was proposed for a dual-arm cooperative robot to achieve high speed for the transfer of a liquid-filled cylindrical container without sloshing. The impedance control method provides efficient results in controlling multi-robot interactions. However, a conventional impedance control is incapable of suppressing the slosh during liquid transfer. Therefore, in this study, we expand the impedance control by introducing a slosh suppression term, which leads to suppressing the slosh successfully during the transport of a liquid container. The effectiveness of the proposed controller was demonstrated for liquid transfer in a 2-D plane.

Drilling Force Control for Robot Manipulator with Combined Rigid and Soft Surface

2013 ◽  
Vol 303-306 ◽  
pp. 1741-1747
Author(s):  
Zahari Taha ◽  
Abdelhakim Deboucha ◽  
Azeddein Kinsheel
Keyword(s):  
Control Problem ◽  
Position Control ◽  
Robot Manipulator ◽  
Industrial Robot ◽  
Drilling Process ◽  
Drilling Force ◽  
Control Scheme ◽  
Soft Surface ◽  
Mass Spring ◽  
Computed Torque

This paper presents an efficient force position control scheme for high precision drilling on soft surfaces using industrial robot. The control problem is divided into two parts; the gross motion control problem and the drilling control problem. In the gross motion stage the robot motion is controlled using computed torque technique. The drilling process is controlled using hybrid force position control that maintains the desired force and trajectory profiles. The soft surface is represented by single degree of freedom mass-spring-damper system. The performance of the system is tested using 6-dof PUMA 560 robot model.

FPGA-Based Intelligent Software Hardening Chip for Computer Numerical Control System

2011 ◽  
Vol 105-107 ◽  
pp. 2217-2220
Author(s):  
Mu Lan Wang ◽  
Jian Min Zuo ◽  
Kun Liu ◽  
Xing Hua Zhu
Keyword(s):  
High Speed ◽  
High Performance ◽  
Large Scale ◽  
Position Control ◽  
Computer Numerical Control ◽  
Numerical Control ◽  
Cnc Machine Tools ◽  
Cnc Machine ◽  
Cnc System ◽  
Intelligent Software

In order to meet the development demands for high-speed and high-precision of Computer Numerical Control (CNC) machine tools, the equipped CNC systems begin to employ the technical route of software hardening. Making full use of the advanced performance of Large Scale Integrated Circuits (LSIC), this paper puts forward using Field Programmable Gates Array (FPGA) for the functional modules of CNC system, which is called Intelligent Software Hardening Chip (ISHC). The CNC system architecture with high performance is constructed based on the open system thought and ISHCs. The corresponding programs can be designed with Very high speed integrate circuit Hardware Description Language (VHDL) and downloaded into the FPGA. These hardening modules, including the arithmetic module, contour interpolation module, position control module and so on, demonstrate that the proposed schemes are reasonable and feasibility.

A Research for Angle Optimization of the SRM Used in Electric Actuator of Valves

2013 ◽  
Vol 404 ◽  
pp. 586-591
Author(s):  
Ding Hong Yang Yang ◽  
Dean Zhao ◽  
Ying Xin Jiang
Keyword(s):  
High Speed ◽  
Position Control ◽  
Experimental Testing ◽  
Optimal Switching ◽  
Switched Reluctance ◽  
Electric Actuator ◽  
Turn On ◽  
Reluctance Motor ◽  
Two Parameters ◽  
Theory Research

This paper uses TMS320F28335 DSP and MAX3032S CPLD as the controller of the 6/4 pole switched reluctance motor (SRM), and controls the motor by the method of current chopping control (CCC) in low speed and the method of angle position control (APC) in high speed. About the optimization of turn-on angle and turn-off angle when SRM is controlled by the method of APC, this paper discusses the optimal design of the two parameters by ways of theory research, simulation and experimental testing. The results show optimal switching angle can make speeded-up of the motor better and improve the performance of SRM.

Hybrid Control of the Berkeley Lower Extremity Exoskeleton (BLEEX)

2005 ◽  
Author(s):  
Lihua Huang ◽  
Ryan Ryan Steger ◽  
H. Kazerooni
Keyword(s):  
Position Control ◽  
Hybrid Control ◽  
System Sensitivity ◽  
Walking Gait ◽  
Mixed Control ◽  
Stance Control ◽  
Control Scheme ◽  
Load Carrying ◽  
Human Limb ◽  
Careful Design

The first functional load-carrying and energetically autonomous exoskeleton was demonstrated at U.C. Berkeley, walking at the average speed of 0.9 m/s (2 mph) while carrying a 34 kg (75 lb) payload. The original BLEEX sensitivity amplification controller, based on positive feedback, was designed to increase the closed loop system sensitivity to its wearer’s forces and torques without any direct measurement from the wearer. The controller was successful at allowing natural and unobstructed load support for the pilot. This article presents an improved control scheme we call “mixed” control that adds robustness to changing BLEEX backpack payload. The walking gait cycle is divided into stance control and swing control phases. Position control is used for the BLEEX stance leg (including torso and backpack) and the sensitivity amplification controller is used for the swing leg. The controller is also designed to smoothly transitions between these two schemes as the pilot walks. With mixed control, the controller does not require a good model of the BLEEX torso and payload, which is difficult to obtain and subject to change as payload is added and removed. As a tradeoff, the position control used in this method requires the human to wear seven inclinometers to measure human limb and torso angles. These additional sensors require careful design to securely fasten them to the human and increase the time to don (and doff) BLEEX.

Sign in / Sign up

Export Citation Format

Share Document