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This paper presents the design construction and working principle of a newly developed opto-tactile sensor for object surface assessment in robotic applications. The sensor provides information about surface texture and this can be used to assist in quality assurance and object recognition tasks. Surface texture causes flexing of protrusions on the sensor surface which in turn rotates a small mirror within the sensor. This rotation is measured optically as a variation in light intensity transmitted between two optical fibers. A mathematical relationship between these light intensity changes and geometrical parameters of the surface texture has been developed. The sensor has been fabricated and tested on a number of different surface textures and preliminary results of sensor output for differing textures are presented. It is envisaged that the sensor will be integrated into a robot system or other intelligent machine to assist with object recognition and evaluation of surface texture.

Stellites are cobalt based super alloys. By virtue of their excellent physio-mechanical properties, stellites are highly regarded engineering materials. Stellites posses high corrosion resistance and wear resistance properties. This study investigates the Stellite deposition process and machinability of Stellite 6 deposited on steel subtrate. Stellite 6 was deposited onto a 4140 bar using a plasma transfer arc (PTA) system and machinability was assessed on the basis of surface roughness. A series of turning operations have been carried out on a conventional lathe using coated carbide inserts and surface roughness was evaluated by Stylus type Surtronic3+ instrument. The values of surface roughness were plotted against different cutting speed, feed rate and depth of cut to display the results in graphical forms. Optimal cutting regimes were established against the best values of surface roughness.

Stellites are cobalt (Co)-based superalloys available in two main combinations: (a) a Tungsten (W) group with composition of Co-Cr-W-C, and (b) a Molybdenum (Mo) group containing Co-Cr-Mo-C. Stellites possess outstanding corrosion resistance, oxidation resistance, wear resistance, heat resistance, and low magnetic permeability. Components made of stellites work well in highly corrosive environments and maintain these advantageous properties at elevated temperatures. Components made of stellites are widely used in the oil and gas, automotive, nuclear power, paper and pulp, chemical and petrochemical, refineries, automobile, aerospace and aircraft industries. By virtue of their nonmagnetic, anticorrosive and non-reactivity to human body-fluid properties, stellites are used in medical surgery and in surgical tools, tooth and bone implants and replacements, heart valves, and in heart pacemakers. The hardness range of stellites is from 32 to 55 HRC, which makes stellites brittle materials but they have a low Young’s modulus. Due to their high hardness, dense but non-homogeneous molecular structure and lower thermal conductivity, machining operations for parts made of stellites are extremely difficult, categorising stellites as difficult-to-machine materials like Ti-alloys, inconels, composites and stainless steels. Usually, machine components made of stellites are produced by a deposition method onto steel substrates instead of expensive solid stellite bars. The rough surfaces of deposited stellites are then finished by grinding, rather than some other economic machining process, which is costly and time-consuming, making stellite products very expensive. This paper provides a basic overview of stellites applicable in engineering, their significances and specific applications, advantages and disadvantages in respect of machining processes.A brief review on experimental research on economically rational cutting parameters for turning operations of Stellite 6 using coated carbide inserts is presented in this paper. Interesting facts on the residual stresses induced by machining processes in Stellite 6 are revealed and analysed. The microhardness variation of machined surfaces of stellite 6 using different tool geometries is investigated in this research review.  It is revealed that coated carbide inserts with a medium-size nose radius perform better in respect of hardness changes and heat generation, producing minimum phase changes on machined surfaces of stellite 6.

The state of the power system has changed over the last decades. Recently, the power system has faced several challenges and issues. On the one side, demands for electrical energy are increasing day-by-day, with power losses, grid failure, and lack of smart technology; on the other side, security threats are also increasing. The current power grid cannot deal with these issues. The Internet of things (IoT) has grown quickly in a very short time because of its main features. By using IoT in the power grid, we can enhance the conventional grid’s efficiency, capacity, reliability, sustainability, scalability, and stability. Using the IoT in smart grids resolves the numerous problems faced by current smart grids. According to the latest research on IoT-enabled smart grid (SG) systems, security issues have been identified as one of the key problems. This paper reviews the different security aspects and applications while integrating the IoT with smart grids and discusses various frameworks. Apart from this, we also focus on various IoT and non-IoT technologies used in the smart grid network, such as sensing, communication, and computing technologies, as well as their standards.