A six-axis single-stage active vibration isolator based on Stewart platform

Abstract

This paper reports on a six-axis vibration isolator for space applications. It is divided into three parts. The first part recalls the principles of active isolation and summarizes the main theoretical results for multiple-axis decentralized control based on force feedback. The second part discusses the technology and describes the evolution of the design over the five years of this project. The third part is devoted to the identification of the transmissibility matrix and the performance evaluation. Zero-gravity tests in parabolic flight are reported. The isolator is proved efficient in a frequency band between 5 Hz and 400 Hz, with a maximum attenuation of-40 dB between 50 Hz and 200 Hz.

Track-position and vibration control simulation for strut of the Stewart platform

“…Still, satellite instruments are subjected to micro-vibration environments, causing problems during on-orbit satellite operation. Much work has been done to prove that the Stewart platform can be used as a vibration isolator (Preumont et al, 2007). Zhen et al (2011) used the Stewart platform with non-cubic configuration to address the active vibration control problem and developed a vibration control system of the strut to attenuate vibration of the Stewart platform caused by the existing micro disturbance.…”

Modeling and Dynamics of a MDOF Isolation System

“…For the MDOF vibration isolation platform, active controllers are the chief method [9][10][11][21][22][23][24][25][26][27]. The key point of the mechanism of active control in MDOF isolator is to generate anti-vibration forces in different directions by actuators and sensors in the designed system.…”

“…The researches of MDOF isolation system are focused on the controllers and control strategies. Different designs and the analysis of the dynamics of parallel mechanism are studied [21][22][23][24][25][26][27], for example, hybrid magnet consisting of electromagnet and permanent magnets is used as the active actuators in Refs. 21 and 22.…”

Dynamic analysis and vibration control of a multi-body system using MSC Adams

“…Geng and Haynes (1993), Graf and Dillmann (1997) and Cobb et al (1999) have investigated the use of Stewart Gough platform for vibration isolation, but they are concentrated on vibrations of small amplitude and as the inertia of the base is much higher than that of the payload, the couple effect of the two platforms is not prominent. Preumont et al (2007) presented a six-axis vibration isolator for space applications by considering the decentralized feedback control approach which has attractive robustness properties. Kapur et al (2007) brought out a method wherein the instantaneous gain in the degrees of freedom of mechanisms at singular configurations can be completely overcome by an appropriate choice of flexural joints in the place of regular joints.…”