Application Notes
1100 Series Applications
1100 Series Applications

The 1100 Series Exciter Heads are capable of imparting static and dynamic forces up to 1000 lbs. each to structures of varying rigidity while providing the highest frequency response available in the industry. read more

5 Axis Machine Tool Dynamic Stiffness Test
5 Axis Machine Tool Dynamic Stiffness Test

Structural dynamics analysis and evaluation are necessary to machine tool design and development to secure good machine tool performance against tough and harsh machining conditions. read more

Advantages of Hydraulic Excitation
Advantages of Hydraulic Excitation

The FFT analyzer has rapidly gained popularity for making frequency response measurements on mechanical systems. One reason for this popularity is the ability of these analyzers to quickly and easily measure frequency response functions using impulsive excitation generated by an impact hammer. read more

Airborne Flutter Excitation
Airborne Flutter Excitation

The AFES is an electro-hydraulic inertial exciter system capable of creating controlled sinusoidal forces up to 400 lbs (1780 N) over a frequency range of 3 Hz to 15 Hz. Force is generated by the acceleration of a 250 lb (114 kg) mass by a hydraulic exciter with a 4 inch (100 mm) maximum stroke and a 600 lb (2670 N) force capability. read more

Dynamic On-Site Testing of Large Structures
Dynamic On-Site Testing of Large Structures

In structural dynamics testing, artificial excitation is an important tool in obtaining controlled data on various structural vibration modes. The testing of very large structures such as bridges, buildings, and ships presents an excitation problem in that it may be impossible to shake the entire structure. read more

Giving Seismic “Vibes” to a Diesel

To assure a diesel engine getting the ‘vibes’ can be quite a task. That’s particularly true when you want to impart seismic vibrations to the 16-cylinder, 16-inch bore engine that has a block weighing close to a quarter million pounds. read more

Jet Engine Multi-Axis Excitation
Jet Engine Multi-Axis Excitation

Input forces or reaction forces in complex machinery may have independent dynamic components in many different directions. For example, an automobile suspension experiences independent horizontal and vertical forces under normal operating conditions.read more

Structural Excitation Techniques
Structural Excitation Techniques

The selection of the proper technique is driven by the nature of the structure under test. Structures must be small because of the limited amount of force available at each spectral line for excitation of the entire structure. read more

Tilted Pad Bearings
Tilted Pad Bearings

This paper reviews a long standing issue related to the stiffness and damping coefficients of tilting-pad (TP) bearings; namely, What is the nature of their frequency dependency?  read more

Understanding & Solving Mechanical Instabilities
Tire Vibration Transmission Part II

Tire modal models are an integral part of automotive NVH vibration transmission simulations. To assess the quality of a tire modal model a correlation study has been performed on axle (spindle) responses of two dynamic load conditions, axle excitation and tire footprint excitation. read more

Understanding & Solving Mechanical Instabilities
Understanding & Solving Mechanical Instabilities

Mechanical instabilities are self-excited vibration phenomena that occur in the machine tool, manufacturing, and process industries. Though not common, instabilities can lead to destructive vibration levels and costly repairs.  read more