Assumption of cutting disturbances in hard turning process (caused by variations in depth of cutting, high passive force Fp or small tool nose radius) could be confirmed with several indicators. These indicators can be monitored during turning process(forces, vibrations, sound, etc.) or after process has been finished (roughness, temperature, wear, etc). Variation of depth of cutting as well as...

Part with sculptured surfaces is obtained in three stages: roughing, semi-finishing and finishing. The roughing operation consists in using flat end tools or fillet end tools on sequential horizontal cutting planes to remove the most material from the raw part as rapidly as possible using “Parallel Planes” or “Offset Contours” machining strategy. When roughing deep parts, radial cutting forces,...

INTRODUCTION There have been increasing reports of annoyance, fatigue, and even neck and back pain during prolonged operation of military propeller aircraft, where persistent multi-axis vibration occurs at higher frequencies beyond human whole-body resonance. This paper characterizes and assesses the higher frequency vibration transmitted to the occupants onboard these aircraft. METHODS Multi...

Multi-frequency scanning near-field optical microscopy, based on a quartz tuning fork-probe (QTF-p) sensor using the first two orders of in-plane bending symmetrical vibration modes, has recently been developed. This method can simultaneously achieve positional feedback (based on the 1st in-plane mode called the low mode) and detect near-field optically induced forces (based on the 2nd in-plane...

Interactions between metal and atomically thin two-dimensional (2D) materials can exhibit interesting physical behaviors that are of both fundamental interests and technological importance. In addition to forming a metal–semiconductor Schottky junction that is critical for electrical transport, metal deposited on 2D layered materials can also generate a local mechanical strain. We investigate t...

An unstable mechanical structure that can self-balance when perturbed is a superior choice for vibration energy harvesting and vibration detection. In this work, a suspended 3D spiral structure is integrated with a triboelectric nanogenerator (TENG) for energy harvesting and sensor applications. The newly designed vertical contact-separation mode TENG has a wide working bandwidth of 30 Hz in lo...

In this case, the diagnosis is admittedly challenging when based on coronal and sagittal images only. Indeed, the os acromiale, an un-united acromial ossification center in adults, is one of the most frequently missed abnormalities by physicians who interpret MR. The reason is twofold. For one, the os acromiale, when viewed in the coronal or sagittal planes, bears a strong resemblance to a norm...

Most of the holographic techniques applied so fa( for non·contacting measurements of surface displacements are highly sensitive. But the interpretation of the interference fringes obtained is usually rather difficult for a non-.expeft. especially for the study of tilts in the presence of lateral in-plane movements. Moire techniques could be applied to overcome some of the difficulties encounter...

This paper reviews the state-of-the art in vibration energy harvesting for wireless, self-powered microsystems. Vibration-powered generators are typically, although not exclusively, inertial spring and mass systems. The characteristic equations for inertial-based generators are presented, along with the specific damping equations that relate to the three main transduction mechanisms employed to...