Shock and Vibration Isolation Systems
A Shock & Vibration Isolation System provides protection against continuous or transient shock and vibration events.
When a shock and vibration environment is deemed to be intolerable for a certain system or piece of equipment, the issue must be addressed through discrete changes that will make the environment acceptable. When this is not possible or practical, shock and vibration must be controlled by isolating the equipment, thereby providing protection to the equipment. Similarly, if the equipment itself is producing the shock and vibration, it may become desirable to mitigate this energy from the surrounding environment.
Mitigation often includes the integration of special hardware including shock absorbers, dampers, vibration isolators, shock isolators, shock transmission units, etc.
Isolation systems de-couple (or isolate) to some degree the input energy to or from the equipment. Some of this energy does filter through typical isolation systems, but isolation system output parameters are normally optimized to reduce the response to an acceptable level. Isolators do not necessarily aim to absorb as much energy as possible, but rather to cause the dangerous input energy to bypass the isolated mass as much as possible.
Most shock and vibration isolation systems consist of a combination of some type of suspension elements (i.e. springs), and an optimized level of damping. Isolation systems are designed to operate along any desired plane or axis of motion, up to 6 degrees of freedom, thereby protecting the isolated payload in up to 3 translational axes and around 3 rotational axes of motion.
Simple isolators with linear output characteristics will provide some level of protection across a given input frequency range. However, Taylor Devices provides specialized isolation systems that can provide higher levels of protection, thereby effectively reducing the energy input to the isolated equipment over a wider frequency bandwidth.
The amount of damping that exists in the isolation system provides a trade-off between response at the resonant frequency of the system and the response at all other frequencies. A low damping level will generally provide a relatively low response over a wide bandwidth but a relatively high response at resonance. Conversely, a high damping level will generally provide a low response at resonance but will sacrifice performance over the remaining frequency range. Other isolator non-linearities such as friction can further sacrifice system performance.
These are general rules, for indeed there are some very specialized vibration isolation system designs that are available from Taylor Devices that provide special characteristics over the entire frequency range, thereby optimizing performance for the protected equipment. Some of these include isolators with friction-free performance, non-linear damping characteristics, non-linear spring characteristics, and strict conformance to any custom requirement.
Now in its 7th decade, Taylor Devices provides full analysis, design, manufacturing and testing services to optimize the attenuation of harmful shock and vibration to equipment.
A Timeline of Past Projects
In 1963, Taylor Devices made a long-term commitment to the field of shock isolation and load suspension. Notable "firsts" achieved include:
- 1963 – Liquid Spring suspension system on two Pontiac test vehicles performed satisfactorily for 15,000 miles without maintenance.
- 1965 – A Chevrolet Corvair equipped with a Taylor Devices Liquid Spring suspension, incorporating active controls, performed satisfactorily for 40,000 road miles, without requiring any maintenance. This car was tested at the General Motors proving ground in 1966 and found to exhibit superior handling characteristics.
- 1967 – A fleet of intercity buses in New Castle, Pennsylvania was equipped with Taylor Suspension Struts. The struts were still in good working order when the buses were retired in 1970.
- 1970 – The world's largest truck, the 350-ton capacity V'Con Mountain Mover, was put into service with a Taylor Liquid Spring Suspension System. With 55 mph off-road speed capacity, the V=Con was (and is) the fastest heavy mining truck ever produced. When the prototype was retired after 5,000 hours of service, the suspension had required no fluid or seal changes.
- 1972 – Taylor Devices Liquid Spring-Dampers were selected by American Motors as the 5 mph bumper absorbers on the 1973 Hornet and Matador Vehicles. This was the world's first production use of compressible fluid devices on an automobile.
- 1980 – Taylor Devices was selected by the U.S. Air Force to be the supplier of the Shock Isolation System on the MPS Based MX Missile. The Taylor Devices Liquid Spring-Damper design used on this program offered patented concepts which reduced the size and weight of the entire missile launcher.
- 1986 – Taylor Devices was selected by the U.S. Air Force to define and study Shock Isolation Systems for large land-based missiles to be deployed in the 1990s.
- 1991 – Large quantities of Taylor Devices Shock Isolators were successfully used in Operation Desert Storm. Most notable was the deadly accurate U.S. Navy Vertically Launched Tomahawk Cruise Missile. Each Tomahawk Missile is protected by eight Liquid Spring Isolators installed in its launch canister.
- 1992 – Experiments at the National Center for Earthquake Engineering Research proved the superiority of Taylor Devices Fluid Viscous Dampers in the attenuation of seismic shock on buildings and bridges. Earthquake resistance improvements of 300% to 500% were found possible, with the dampers reducing both stress and deflection in both steel and reinforced concrete structures.
- 1993 – The County of San Bernardino, California selected Taylor Viscous Damping Devices for seismic isolation of five buildings of its new Medical Center at Colton, California. More than 180 dampers were required, each with 320,000 pounds output and a stroke of 48 inches.
- 1994 – Taylor Devices provides the U.S. Army with an electronically controlled active shock isolation system. The isolation system is used for protection of critical guidance system components on the THAAD Surface to Air Missile.
- 1995 – The Pacific Bell Northern Area Network Communications Center in Sacramento, California is equipped with Taylor Devices Fluid Viscous Dampers. The dampers are used as bracing elements within the walls of this 300,000 square foot structure and will allow the structure to remain occupied and damage free after major earthquakes.
- 1997 – The State of Washington selected Taylor Fluid Viscous Dampers for seismic protection on the three-section roof of the new Pacific Northwest Baseball Park in Seattle. The unique retractable roof design required more than 6.5 million pounds of damping force, provided by eight large Taylor dampers.
- 2000 – The State of California utilizes Taylor Fluid Viscous Dampers for seismic protection of the San Francisco-Oakland Bay Bridge. This retrofit provides a seismic performance upgrade of this previously damaged bridge (1989 Loma Prieta earthquake), so that the bridge can be utilized immediately after a major earthquake.
- 2002 – NASA and the U.S. Air Force selected a Taylor Devices Active Isolation System for wind motion control on the new Evolved Expendable Launch Vehicle (EELV) used to augment the Space Shuttle fleet.
- 2004 – The U.S. Special Operations Command selects a Taylor Devices Controllable Isolation System for all seats on the Mark V Special Operations Craft. This craft is typically used for operational deployment of Navy SEAL teams. The Taylor Seat Isolation System was proven to substantially reduce neck and back injuries to personnel during extensive testing and field evaluations.
- 2007 – The U.S. Government selects Taylor Devices' products for the Carriage to Ground Isolation System on the M-777 Ultralightweight 155mm Towed Field Howitzer.
- 2012 – The U.S. Government selects Taylor Devices’ Landing Gears, utilizing non-pressurized hybrid spring elements, for full-scale production on a major unmanned air vehicle program.
- 2016 – NASA selects Taylor Devices Spring Dampers as actuators for the hatch door and umbilical separation system on the CST-100 Space Vehicle for missions to the International Space Stations.
- 2017 – NASA selects Taylor Devices Spring Damper Actuators for use on the Launch Abort System for the Orion Space Vehicle intended for use outside Earth’s orbit.
- 2017 – The U.S. Navy utilizes a large-scale Taylor Devices Tension-Compression Shock Isolation System for the weapons modules on the DDG-1000 Zumwalt Class “Stealth” Destroyer, in addition to smaller Tension-Compression Isolators on each missile cannister in the ships' weapons load-out.