Excitation Systems: What They Are And How They Are Used
Frequency response measurements on mechanical systems are made by an FFT analyzer. This is not the only method of measuring, but it has become one of the most popular because of its ability to analyze quickly and easily by using an impact hammer. When structures are damped and linear, torsional excitation methods provide good results and predict behaviors of the structure in the future. Electrodynamic shakers might also be involved in the evaluation. What creates challenges is the fact that many structures in real-life feature nonlinear designed or higher damping than usual. The response might change dramatically when in real use, so a measurement is required to determine how the structure will respond to different environments. This is when an exciter is used in order to duplicate the real-world conditions. When an exciter system is properly designed and used in the right manner, it is one of the best tools for measuring high energy situations.
The main features that are important for measure response include high force capability, high frequency response, ease of fixturing and preload capability. High force capability is a great way to test smaller structures that are highly damped, as well as for non-linear structures. This method allows the use of broadband random exciters that produce a faster result. Ease of fixturing provides a compact point of force applied directly to the structure. High frequency response attempts to achieve the same response at low and high frequencies and preload capability request an accurate control of preload force such as the slack in bearings, joints and gears.
Other benefits of the hydraulic system include independent static and dynamic control that allows independent control of separate feedback variables. Users are able to control the dynamic input fore while maintaining a static displacement control, keeping the exciter from driving to the end of its stroke. Automatic gain compensation is also possible, maintaining a constant level of force to compensate for variation in the stiffness of the tested structure. Long stroke also provides several inches of stroke for testing in the case of vehicle suspensions.
Xcite Systems offers a variety of exciter models including linear and inertial mass exciters. They can be used for backup fixturing, which is often difficult, especially when testing buildings, turbine rotors and ship borne structures or automotive drivelines. The system allows structural dynamists to apply pure moments in structures during evaluation. The systems have been used in the development of anti-lock brake systems, diesel engines, automotive axles, half-axles and turbine rotors.
Several models are available. The Xcite 1100 Series of Modal Exciters are used in component testing, as well as total vehicle or structure excite situations. This system allows a bench simulation, providing a chance for engineers to evaluate the fixes in less time and for less money. With the 1200-9 Continuous Rotation System, it allows engineers to excite structures while they are rotating at speeds as much as 4,000 rotations per minute. This measures the bending mode frequencies of steam turbine rotors and blades while under normal operating conditions.
The main features that are important for measure response include high force capability, high frequency response, ease of fixturing and preload capability. High force capability is a great way to test smaller structures that are highly damped, as well as for non-linear structures. This method allows the use of broadband random exciters that produce a faster result. Ease of fixturing provides a compact point of force applied directly to the structure. High frequency response attempts to achieve the same response at low and high frequencies and preload capability request an accurate control of preload force such as the slack in bearings, joints and gears.
Other benefits of the hydraulic system include independent static and dynamic control that allows independent control of separate feedback variables. Users are able to control the dynamic input fore while maintaining a static displacement control, keeping the exciter from driving to the end of its stroke. Automatic gain compensation is also possible, maintaining a constant level of force to compensate for variation in the stiffness of the tested structure. Long stroke also provides several inches of stroke for testing in the case of vehicle suspensions.
Xcite Systems offers a variety of exciter models including linear and inertial mass exciters. They can be used for backup fixturing, which is often difficult, especially when testing buildings, turbine rotors and ship borne structures or automotive drivelines. The system allows structural dynamists to apply pure moments in structures during evaluation. The systems have been used in the development of anti-lock brake systems, diesel engines, automotive axles, half-axles and turbine rotors.
Several models are available. The Xcite 1100 Series of Modal Exciters are used in component testing, as well as total vehicle or structure excite situations. This system allows a bench simulation, providing a chance for engineers to evaluate the fixes in less time and for less money. With the 1200-9 Continuous Rotation System, it allows engineers to excite structures while they are rotating at speeds as much as 4,000 rotations per minute. This measures the bending mode frequencies of steam turbine rotors and blades while under normal operating conditions.
