Internal and External Forces Measurement of Planar 3-DOF Redundantly Actuated Parallel Mechanism by Axial Force Sensors

This paper proposes a method for measuring the internal and external forces of a planar 3-DOF (degree of freedom) redundantly actuated parallel mechanism. The internal forces, force acts inside the endplate and mechanism constraint force, and the external forces, forces act on the endplate and thrusts by actuators, were measured simultaneously using the axial forces of the rods. Kinetostatic equations of the parallel mechanism were used to derive algorithms for measuring the internal and external forces. A link axis force sensor was developed using a strain gauge sensor. To verify the actual internal force of the endplate, a force sensor was also installed on the endplate. A real-time system for measuring the forces of the parallel mechanism was developed using RT-Linux. The external and internal forces were measured accurately.

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ANALISIS PENGARUH PEMODELAN SAMBUNGAN TITIK BUHUL PADA STRUKTUR KUBAH GEODESIK

JMTS: Jurnal Mitra Teknik Sipil ◽

10.24912/jmts.v0i0.10725 ◽

2021 ◽

Vol 4 (2) ◽

pp. 503

Author(s):

Rivven Meilvin ◽

Leo S. Tedianto

Keyword(s):

Axial Force ◽

Joint Modeling ◽

Internal Force ◽

Cross Sectional ◽

Axial Forces ◽

Translational Displacement ◽

Single Structure ◽

Dome Structure ◽

Internal Forces ◽

Geodesic Dome

The geodesic dome consists of steel rod elements joined together to form a single structure. Generally, these geodesic domes are analyzed by assuming the joints of the gusset points are joints and only receive axial forces on the rods. However, in reality, it is not easy to apply gusset joints as pure joints in construction. This research will analyze the geodesic dome by modeling the joints of the gusset points as joints where there is only axial force arising on the rods and modeling the rigid gusset points where there will also be moments and shear on the rods. The analysis will only be carried out by comparing the value of the displacement at each gusset joint modeling and checking the cross-sectional dimensions of the internal forces that arise with the help of the MIDAS GEN program in modeling the geodesic dome structure which has a diameter of 20000 mm and a height of 10000 mm with the type of steel profile. used is a pipe profile using two types of geodesic dome, namely type 2V and 3V. For loads that are calculated, namely dead load, live load, and wind load. The results showed a relatively small difference in translational displacement and the axial force was relatively the same in the internal force analysis, so it is better if the analysis by modeling the gusset connection as rigid.ABSTRAKKubah geodesik terdiri dari elemen batang baja yang disambung menjadi satu kesatuan struktur. Umumnya kubah geodesik ini dianalisis dengan menganggap sambungan titik buhulnya berupa sendi dan hanya menerima gaya aksial saja pada batang - batangnya. Namun pada kenyataannya untuk mengaplikasikan sambungan titik buhul sebagai sendi murni pada konstruksi tidaklah mudah. Penelitian ini akan menganalisis kubah geodesik dengan memodelkan sambungan titik buhulnya sebagai sendi dimana hanya ada gaya aksial saja yang timbul pada batang - batangnya dan memodelkan titik buhulnya rigid dimana akan terjadi juga momen dan geser pada batang tersebut. Analisis hanya akan dilakukan dengan membandingkan nilai dari perpindahan pada setiap pemodelan sambungan titik buhul dan pengecekan dimensi penampang terhadap gaya – gaya dalam yang timbul dengan bantuan program MIDAS GEN dalam memodelkan struktur kubah geodesik yang mempunyai diameter 20000 mm dan tinggi 10000 mm dengan jenis profil baja yang digunakan adalah profil pipa dengan menggunakan dua tipe kubah geodesik yaitu tipe 2V dan 3V. Untuk beban yang diperhitungkan yaitu beban mati, beban hidup, dan beban angin. Hasil penelitian menunjukkan nilai perbedaan yang relatif kecil pada perpindahan translasi dan diperoleh gaya aksial yang relatif sama pada analisis gaya dalam yang timbul, sehingga sebaiknya analisis dengan pemodelan sambungan titik buhul sebagai rigid.

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Hybrid Force and Position Control Strategy of Robonaut Performing Object Transfer Task

MATEC Web of Conferences ◽

10.1051/matecconf/201816005003 ◽

2018 ◽

Vol 160 ◽

pp. 05003

Author(s):

Gang Chen ◽

Yu-Qi Wang ◽

Qing-Xuan Jia ◽

Pei-Lin Cai

Keyword(s):

Control Strategy ◽

Position Control ◽

Control Method ◽

Transfer Task ◽

Internal Force ◽

Matlab Simulation ◽

Constraint Force ◽

Common Control ◽

Transfer Operation ◽

External Forces

This paper proposes a coordinated hybrid force/position control strategy of robonaut performing object transfer operation. Firstly, the constraint relationships between robonaut and object are presented. Base on them, the unified dynamic model of the robonaut and object is established to design the hybrid force/position control method. The movement, the internal force and the external constraint force of the object are considered as the control targets of the control system. Finally, a MATLAB simulation of the robonaut performing object transfer task verifies the correctness and effectiveness of the proposed method. The results show that all the targets can be control accurately by using the method proposed in this paper. The presented control method can control both internal and external forces while maintaining control accuracy, which is a common control strategy.

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Force optimization of planar 2-DOF parallel manipulators with actuation redundancy considering deformation

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406212458055 ◽

2012 ◽

Vol 227 (6) ◽

pp. 1371-1377 ◽

Cited By ~ 13

Author(s):

Jun Wu ◽

Tiemin Li ◽

Boqiang Xu

Keyword(s):

Parallel Manipulator ◽

Driving Forces ◽

Parallel Manipulators ◽

Optimization Method ◽

Internal Force ◽

Actuation Redundancy ◽

Force Optimization ◽

Redundantly Actuated ◽

Internal Forces ◽

Novel Method

Internal force distribution is one of the most important issues for redundantly actuated parallel manipulators. This article presents a novel method for optimizing internal force to minimize the deformation of key components in a parallel manipulator. The dynamic model is first derived, and then an objective function is proposed by giving different weights on internal forces of different components based on its flexibility. The deformation of the component with big flexibility is minimized. A planar 2-DOF parallel manipulator with actuation redundancy is taken as an example to validate the force optimization method. The simulation results show that the deformation of the manipulator with the force optimization method proposed in this article is smaller than that with the traditional method to minimize the norm of driving forces. Thus, the manipulator precision can be improved.

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Sensor-Based Estimation and Control of Forces and Moments in Multiple Cooperative Robots

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.1766029 ◽

2004 ◽

Vol 126 (2) ◽

pp. 276-283 ◽

Cited By ~ 12

Author(s):

Manish Kumar ◽

Devendra P. Garg

Keyword(s):

Fuzzy Logic ◽

Fuzzy Logic Controller ◽

Internal Force ◽

End Effector ◽

Use Of Data ◽

Intelligent Behavior ◽

Internal Forces ◽

Estimation And Control ◽

External Forces ◽

And Control

Control of multiple robots presents numerous challenges, some of which include synchronization in terms of position, motion, force, load sharing and internal force minimization. This paper presents formulation and application of a fuzzy logic based strategy for control of two 6 degree-of-freedom robots carrying an object in a cooperative mode. The paper focuses on control of internal forces that get generated when two or more robots carry an object in coordination. Force/torque (F/T) sensors mounted on wrist of each robot provide the force and torque data in six dimensions. A fuzzy logic controller has been designed to use these force/torque (F/T) data to achieve a cooperating movement in which one robot acts as leader and the other robot follows. The paper also deals with estimation of external forces acting on end effector with the use of data provided by F/T sensors. These external forces and moments are not directly measured by F/T sensor since the quantities measured by F/T sensor are corrupted by the dynamics of the end effector and manipulator (a F/T sensor is usually mounted between wrist and end effector of the robot). This paper investigates the use of Kalman filtering technique to extract the external forces acting on robot end effector utilizing the underlying dynamics of the end effector. Matlab’s Fuzzy logic, Simulink, and State Flow toolboxes are used for achieving real-time, autonomous and intelligent behavior of the two robots. Simulation results from two separate experiments show that the above strategy was able to constrain the internal forces and provide a smooth movement of the manipulators.

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1A1-J07 Internal and External Forces Measurement of Planar 3-DOF Redundantly Actuated Parallel Mechanism by Axial Force Sensors(Parallel Robot/Mechanisms and its Control)

The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) ◽

10.1299/jsmermd.2012._1a1-j07_1 ◽

2012 ◽

Vol 2012 (0) ◽

pp. _1A1-J07_1-_1A1-J07_3

Author(s):

Takashi HARADA ◽

Podi LIU

Keyword(s):

Axial Force ◽

Parallel Mechanism ◽

Parallel Robot ◽

Force Sensors ◽

Redundantly Actuated ◽

External Forces

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Error Analysis in Calculating the Internal Force of Plane Statically Determinate Truss by the Original Size Principle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.1168 ◽

2012 ◽

Vol 268-270 ◽

pp. 1168-1171

Author(s):

Dan Ma ◽

Yan Dong Qu ◽

Xiang Qing Kong

Keyword(s):

Internal Force ◽

Calculation Error ◽

Size Principle ◽

Tensile Stiffness ◽

Mechanics Of Materials ◽

Internal Forces ◽

Original Size ◽

External Forces ◽

The Given ◽

Small Deformations

Ignoring the deformation effect, the original size principle is normally used to calculate the internal force and deformations of the bars in Mechanics of Materials, the calculation error is not discussed in the textbooks, however. In order to show the adaptability of the original size principle to calculate the internal force of plane statically determinate truss, a case of the two-bar statically determinate truss was also given. The calculation error of the internal force and the angle deformations are quantitatively studied to make a comparison between the actual internal force and that calculated by the original size principle. The research showed that the relative error of angle deformations and the internal forces of the two rods are nonlinear dependent on the external forces (the given force), tensile stiffness and the initial angle of the plane truss. If the strength and tensile stiffness of the bars can meet the requirements of engineering, the original size principle can be used to calculate the internal force of metallic bar truss under the conditions of small deformations.

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Real-Time System for Sending Data from Three Clients to One Server with MATLAB

ACMIT Proceedings ◽

10.33555/acmit.v2i1.7 ◽

2015 ◽

Vol 2 (1) ◽

pp. 35-41

Author(s):

Rivan Risdaryanto ◽

Houtman P. Siregar ◽

Dedy Loebis

Keyword(s):

Information System ◽

Real Time ◽

Time System ◽

Real Time System ◽

The Real ◽

Performance Time ◽

Data Process ◽

Effectiveness And Efficiency

The real-time system is now used on many fields, such as telecommunication, military, information system, evenmedical to get information quickly, on time and accurate. Needless to say, a real-time system will always considerthe performance time. In our application, we define the time target/deadline, so that the system should execute thewhole tasks under predefined deadline. However, if the system failed to finish the tasks, it will lead to fatal failure.In other words, if the system cannot be executed on time, it will affect the subsequent tasks. In this paper, wepropose a real-time system for sending data to find effectiveness and efficiency. Sending data process will beconstructed in MATLAB and sending data process has a time target as when data will send.

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