Broad-band Viscoelastic Rotational Vibration Control for Remote Sensing Applications

Abstract

The ability to eliminate, or effectively control, vibration in remote sensing applications is critical. Any perturbations of an imaging system are greatly magnified over the hundreds of kilometers from the orbiting space platform to the Earth's surface. Space platforms, such as the International Space Station, are not as predictable or stable as many other spacecraft. Therefore, an effective vibration isolation and/or absorber system is needed that operates over a wide range of excitation frequencies. A passive system is also preferred to reduce the resources required, as well as to provide a reliable and self-contained system. To accomplish these goals, a vibration amplitude limiting system has been developed that uses both vibration isolation and absorber components. Viscoelastic structural elements that act as both a spring and a damper in a single element are implemented in the design. This configuration also demonstrates a favorable frequencydependent response and produces a system with improved dynamic behavior compared to conventional spring and damper designs. This rotation limiting vibration system has been designed and analyzed for use in digital remote sensing imaging. The transmissibility and the ground jitter associated with the system are determined. A summary of these results will be presented along with a comparison to a more conventional vibration isolation/absorber system.

Modeling and experimentation of a viscoelastic microvibration damper based on a chain network model

“…Viscoelastic (VE) dampers are among the earliest types of passive control devices that have been successfully utilized to reduce the structural dynamic responses induced by types of vibration excitations, including earthquakes, wind, mechanical vibrations, human activity, etc. Owing to their advantages of simple construction, easy manufacturing process, low cost and excellent energy dissipation capacity, VE dampers have been widely used as vibration control devices in the fields of civil buildings, bridges, spacecraft and machinery by researchers and engineers in recent decades [Soong and Spencer 2002;Webster and Semke 2005;Rao 2003; Marko et al 2006;Rashid and Nicolescu 2008].…”

Equivalent fractional Kelvin model and experimental study on viscoelastic damper

“…VE dampers not only have the advantages of simple construction, easy manufacture, good durability and low cost, but they also have high energy dissipation capacity, which can effectively reduce structural dynamic responses. In the current paper, VE dampers have been applied to many structures for reducing the responses due to many types of vibrations and can be effective in reducing the responses of structures (Samali and Kwok, 1995;Tan and Ko, 2004;Webster and Semke, 2005;Garcı´a et al, 2007, Moliner et al, 2012. Therefore, extensive investigations have been focused on the properties of VE dampers and the effects of VE dampers on structures.…”

Design of micro-vibration isolation system for a remote-sensing satellite payload using viscoelastic materials

“…Vaillon and Philippe (1999) designed and tested an elastomer-based passive vibration isolator for reducing micro-vibrations onboard. Webster et al (2005) has designed and analyzed an effective rotational vibration absorption and isolation system for use in space borne remote sensing. Oh et al (2005;2006) designed and fabricated a variable-damping bio-metal fiber value isolator and conducted dynamic tests on the isolator using a flywheel.…”

“…Sorbothane shows a nonlinear behavior that is a great advantage to isolation. It has relatively high damping at low frequencies, which allows resonant points to be controlled, and lower damping at higher frequencies, which results in better isolation at higher frequencies (Webster & Semke, 2005). In this paper, small square Sorbothane pads are designed as viscoelastic isolators located under the camera, between the camera and satellite bus to reduce the effects of reaction wheel micro-vibrations on the camera and provide higher image quality.…”