The design, control and performance of the Cobotic Hand Controller, a novel, six-degree-of-freedom, admittance controlled haptic display is examined. A highly geared admittance architecture is often used to render high impedances with reasonable sized actuators for a haptic display. The Cobotic Hand Controller is an extremely faithful realization of an admittance display, since it is capable of...

This paper presents the use of Acoustic Emission to study the running-in and subsequent micropitting of a pair of hardened steel surfaces under mixed lubrication conditions. These surfaces were loaded together under rolling/sliding conditions typical of heavily loaded gearing. Relocation profilometry was used to measure the rapid running-in process and the development of micropits. Acoustic emi...

. Abstract—The demand for high quality focuses attention on the surface condition of the product, especially the roughness of the machined surface, because of its effect on product appearance, function, and reliability. Surface quality is one of the specified customer requirements for machined parts. There are many parameters that have an effect on surface roughness such as cutting speed, feed ...

Actuators remain a limiting factor in robotics, especially in microrobotics where the power density of actuators is a problem. A 3 × 3 × 8.7 mm 3-axis piezoelectric ultrasonic micromotor system is described here in an effort to help solve this problem. Formed from 4 bulk lead zirconate titanate (PZT) thickness-polarized elements placed around the periphery of a rectangular rod, the stator is de...

Alloy ASTM A710 (HSLA-80) is a co-precipitation hardened steel with a desirable combination of mechanical properties and weldability, making it an excellent candidate for use in structural applications such as bridges, shipbuilding, and pipelines. There have been extensive studies of the strengthening mechanisms, effect of heat treatment and continuous cooling, and kinetics of the precipitation...

The addition of cobalt was experimentally observed to increase the strength and impact toughness of Cu precipitation hardened steel. In order to understand the mechanism of this strengthening, we studied the effect of cobalt in the bulks and surfaces of bcc Fe and bcc Cu, as well as at the Fe/Cu interface by ab initio density-functional approach. We investigated the cobalt distribution between ...

dynamic recrystallization, drx, behaviour of a precipitation hardened, ph, stainless steel was studied in connection with microstructural developments in a compression test. the experimental results showed that the dominant mechanism of softening is drx, but at high strain rates and low temperatures, ie, high zener-holman parameter, z, work hardening and dynamic recovery, drv, produced a pancke...

Pre-hardened steel (P20) is a widely used material in the production of moulds/dies due to less wear resistance and used for large components. In this study, minimization of surface roughness has been investigated by integrating design of experiment method, Response surface methodology (RSM) and genetic algorithm. To achieve the minimum surface roughness optimal conditions are determined. The e...

This paper presents a systematic procedure for the optimization of machining parameters such as cutting speed, feed rate, nose radius, edge radius, and rake angle to reduce specific material removal energy and improve energy efficiency in the hard turning of AISI 4140 steel. A simulation approach was applied in conjunction with the design of experiment (DOE), mathematical approximation with a m...

This paper presents a new approach for surface roughness (Ra) prediction during milling by using dynamometer to measure cutting forces signals and cutting conditions. End milling machining process of hardened die steel with carbide end mill, was modeled in this paper using the adaptive neuro fuzzy inference system (ANFIS) to predict the effect of machining variables (spindle speed, feed rate an...