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Thermal and tool wear characterization of graphene oxide coated through magnetorheological fluids on cemented carbide tool inserts

Thiyagu M., Karunamoorthy L., Arunkumar N.

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

1043--1055

EN

The proposed work is about the investigation of nano-textured tool insert with magnetor-heological-based graphene coating process. The comparative study on nano-textured car-bide insert with unpolished one for turning duplex stainless steel (S31803/2205) is made by conducting number of experiments with Box–Behnken design using response surface methodology. An array of sensor based on the conductive element of chromel and alumel core integrated through DC magnetron sputtering on the rake surface of the tool insert. The performance of the proposed sensor was evaluated from the obtained thermo-electromotive force on tool chip contact interference and the temperature measurements taken at the contours of multiple points with respect to the tool wear. Results obtained clarify that with the rise in cutting tool temperature leads to the rise in tool wear based on the adhesion and abrasion. It has been found that the graphene coated tool inserts provides high wearable resistances with flank wear of 0.298 mm at 21st pass. The cutting tool temperature is found to spread uniformly with a value of 202 8C for graphene coated inserts for cutting speed of 55 m/min. Microstructural images taken proved that the formation of cementite and carbides with inter metallic compounds (IMCs) produced during the tool chip interface leads to the strengthening of tool tip in reducing the tool-wear. Also the occurrence of ultrafine grain boundaries on the tool tip occurs increasing the formation of covalent bonds in providing the robust resistance against tool wears.

2

Adaptive control of frictional contact models for nonholonomic wheeled mobile robot

Vivekananthan R., Karunamoorthy L.

Journal of Automation Mobile Robotics and Intelligent Systems

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2011

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Vol. 5, No. 4

30-34

EN

Mobility of the robot depends on the vehicle dimensions, locomotion principles and wheel characteristics. The function of the wheel is to carry the load and to produce the traction force. The main factors of wheel terrain interaction are bearing capacity of ground, traction performance of the wheel and geometry of terrain profile. In this paper the system and control concepts of the wheeled robot is discussed in more detail, within the framework provided by the wheel terrain contact model. The dynamic model of the wheeled robot is presented by considering contact forces of the wheel due to their relative motion of the wheel and contact plane. Finally, a dynamic relation is introduced and results are presented in terms of forces, torques and displacements related to wheel terrain interaction. To estimate the forces in the system arising from the interaction between a deformable wheel and rigid terrain using the software package Ansys 10.0. Simulations were performed using Matlab- Simulink program and the results are shown that the proposed controller can overcome the influences the effect of contact forces in order to achieve the desired trajectory.

3

A Time optimal path planning for trajectory tracking of wheeled mobile robots

Vivekananthan R., Karunamoorthy L.

Journal of Automation Mobile Robotics and Intelligent Systems

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2011

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Vol. 5, No. 2

35-41

EN

Avariety of approaches for trajectory tracking control of wheeled mobile robots have been implemented. This paper presents a model for a time optimal motion control based on fuzzy logic algorithm for a three wheeled nonholonomic mobile robot with desired function. Simplified kinematic equations of a differentially driven robot are designed to follow the path with evaluated linear and angular velocities. Here, the proposed kinematic model is based on a simple geometric approach for getting the desired position and orientation. The speeds are varied depending on the variations in the path and on the posture of the robot. The robot is subjected to move in a constrained workspace. The control architecture was developed based on fuzzy logic algorithm to obtain time optimal motion control of robot trajectory tracking. The kinematic model was done on Matlab software environment and profound impact on the ability of the nonholonomic mobile robot to track the path was evaluated.