A helicopter is not possessed of an ability to fly fast compared with fixed-wing counterparts. This is a result of considerations with the main rotor. The main rotor moves in a direction very close to its plane of rotation which naturally divides it into two halves which operate under different aerodynamic conditions. One side (called the advancing side) has the rotation and translation velocit...

For a traveling wave rotary ultrasonic motor, matching the stator with proper flexible rotor can be challenging because of actual contact mechanism’s complexity. Due to lack effective evaluation and prediction means in design process, prototype test is usually needed truly measure how well it performs, leading high cost long cycle. In order solve this problem, an efficient performance method ba...

Titanium alloy and its thin-walled structures are widely used in the aerospace field. Aiming at processing chatter difficult-to-machine problem of titanium workpieces, rotary ultrasonic milling technology (RUM) is employed to restrict machining vibration this paper. Firstly, for describing dynamic characteristics, web with low stiffness equivalent a mass-spring-damping system three degrees free...

AIM To evaluate the effect of diode laser and ultrasonics with and without ethylenediaminetetraacetic acid (EDTA) on the smear layer removal from root canals. MATERIALS AND METHODS A total of 120 mandibular premolars were decoronated to working the length of 12 mm and prepared with protaper rotary files up to size F3. Group A canals irrigated with 1 ml of 3% sodium hypochlorite (NaOCl) follow...

The majority of all gas measurement used in the world today is performed by two basic types of meters, positive displacement and inferential. Positive displacement meters, consisting mainly of diaphragm and rotary style devices, generally account for lower volume measurement. Orifice, ultrasonic and turbine meters are the three main inferential class meters used for large volume measurement tod...

Piezoelectric traveling wave rotary ultrasonic motors are motors that generate torque by using the friction force between a piezoelectric composite ring (or disk-shaped stator) and a metallic ring (or disk-shaped rotor) when a traveling wave is excited in the stator. The motor speed is proportional to the amplitude of the traveling wave and, in order to obtain large amplitudes, the stator is ex...