Systems that exhibit flexible dynamics are susceptible to vibration caused by changes in the reference command, as well as, from external disturbances. Feedback control is an obvious choice to deal with these vibrations, but in many cases, it is insufficient or difficult to implement. Input shaping has proven beneficial for reducing vibration that is caused by changes in the reference command. ...

Hand-arm vibration syndrome (HAVS) is a symptom entity that consists of disturbances in the circulation of the fingers (Vibration White Finger or VWF), peripheral nerves of the hands and arms, and possibly muscle, joint and autonomic nervous system disorders. Changes in HAVS were assessed in a cross-sectional and in a longitudinal study of forestry workers. Sensorineural and musculoskeletal sym...

Human exposure to whole-body vibration (WBV) has been associated with a variety of changes in health, comfort, and occupational functioning. In the C-130J Hercules aircraft, crews from both Australia and overseas have reported that the vibration in the cargo compartment of the aircraft exceeds previous levels and that it is both annoying and fatiguepromoting. This report examines the issue of h...

Vehicle drivers receive tactile feedback from steering-wheel vibration that depends on the frequency and magnitude of the vibration. From an experiment with 12 subjects, equivalent comfort contours were determined for vertical vibration of the hands at two positions with three grip forces. The perceived intensity of the vibration was determined using the method of magnitude estimation over a ra...

Article history: Received: 06.02.2015. Received in revised form: 11.05.2015. Accepted: 15.05.2015. Due to the shortcomings of one mass vibration mill such as inefficiency, high energy consumption and big noise, a double mass high energy vibration mill, in which transient high vibration intensity is produced, is investigated by applying the non linear vibration theory. The nonlinear hard feature...

The effects of vibration parameters, operating conditions and material properties on bed voidage were investigated using an optical fiber probe approach in a vibrating fluidized bed with a diameter of 148 mm. Variables studied included frequency (0-282 s), amplitude (0 mm-1 mm), bed height (0.1 m-0.4 m) as well as four kinds of particles (belonging to Geldart's B and D groups). The axial and ra...

Abstract-Vibration measurements have been used to reliably diagnose performance problems in machinery and related mechanical products. A vibration data collector can be used effectively to measure and analyze the machinery vibration content in gearboxes, engines, turbines, fans, compressors, pumps and bearings. Ideally, a machine will have little or no vibration, indicating that the rotating co...

With the trend of lighter vehicle and more powerful engine (power plant) passengers are subjected to large vibration and harshness coming from the engine through the chassis. This paper discusses the application of active vibration control to reduce this vibration effect. Using a mass-spring-damper model which represents a passive engine mount, dynamic characteristic of the mount is obtained fo...

Vibration analysis has been conducted on large rotating machines for many decades. Proximity probes and accelerometers are traditionally used to measure bearing and shaft vibration in an effort to keep mechanical condition in check. Simple measurement of amplitude, to the more complex analysis such as Fast Fourier Transforms, are made by maintenance personnel in an effort to identify the source...

At present there appears to be a need for research conducted on the effects of vibration on the contractile ability of skeletal muscle tissue. The aim of this study was to address this issue by examining the effects of a superimposed muscle/tendon vibration at 50.42±1.16 Hz (acceleration 13.24 ± 0.18ms(-2): displacement ≈5mm) on muscular activation and maximal isometric contraction. Sixteen par...