Since there are backlash friction and time-varying stiffness, the characteristics of gear pair has strong nonlinearity. When a gear has faults such as pitting, spalling and tooth breakage, there are often some nonlinear characteristics as super-harmonics or sub-harmonics along with vibration signal. These characteristics will cause some difficulty for fault diagnostics, so it is necessary to st...

Original scientific paper The relationships between the existence of gear teeth cracks as a cause and symptoms emerging as housing vibrations that can be detected with signals measured was investigated numerically and experimentally. Experimental measurements on one-stage gear drives have been carried out involving gears built in with different notch length in tooth root. Signals measured as ac...

BACKGROUND In-line skate injuries are highly preventable by the use of protective gear. We investigated how young Dutch skaters protect themselves and what factors predict the use of protective gear in order to develop campaigns to increase their safety behaviour. METHODS A survey was conducted to study protection behaviour of 872 Dutch skaters and factors influencing the use of protective ge...

− Evaluation of measurement performance of a gear measuring instrument (GMI) is not easy task since a master gear with sufficient accuracy has not been available. The manufacturing the master gear with an ideal involute form is very difficult and the accuracy of the master gear is not able to be estimated. Therefore, we have proposed a new artifact named Double Ball Artifact (DBA) which consist...

The continuously variable transmission (CVT) is a type of transmission that can adopt any arbitrary gear ratio. Whereas typical transmissions utilize toothed gears, the CVT employs a sphere in rolling contact with a set of rollers; loads applied to the CVT are supported across these rolling contacts, resulting in microslips of varying amounts at each contact area. In this paper, we describe the...

Java cellular phone has arrived in the marketplace as the latest device of a mobile gear. The gear is very compact, allowing 10KB for Java program size and 5KB for data size. Although small in size, it features innovative computer system architecture. Java program can be sent dynamically to the gear in a streaming manner over wireless network. In addition, compared to conventional mobile comput...

In this paper artificial neural networks and support vector machines are used to reduce the amount of vibration data that is required to estimate the Time Domain Average of a gear vibration signal. Two models for estimating the time domain average of a gear vibration signal are proposed. The models are tested on data from an accelerated gear life test rig. Experimental results indicate that the...

Gear design optimization consists of several objectives such as centre distance, weight, fatigue strength, tooth deflection depending on the requirements. Among these objectives the weight of a gear train is one of the best considerable designs, since many power transmission applications require low weight. The advanced optimization technique, Genetic Algorithm (GA) is used to find the optimal ...

Opportunities exist for developing the Acoustic Emission (AE) technique on various forms of rotating machinery, such as gearboxes. This paper provides a short summary on recent developments in the application of AE to gear defect diagnosis, and, experimental results are presented that examine and explore the effectiveness of AE for seeded gear defect diagnosis. It is concluded that the applicat...

As one of the most common gear failure modes, tooth wear can produce nonlinear modulation sidebands in the vibration frequency spectrum. However, limited research has been reported in monitoring the gear wear based on vibration due to the lack of tools which can effectively extract the small sidebands. In order to accurately monitor gear wear progression in a timely fashion, this paper presents...