Microgravity Vibration Isolation Subsystem (MVIS) was designed to allow experiments to be conducted in low gravity without interference from vibrations produced by the International Space Station (ISS). Through collaboration with the European Space Agency in their Fluid Science Laboratory (FSL), MVIS will aim to improve the opportunities for the exploitation of microgravity vibration isolation technology.Facility Manager(s)
Bristol Aerospace Limited, Winnipeg, Manitoba, Canada
MacDonald Detweiller and Associates, Rockville, MD, United States
Canadian Space Agency (CSA)Expeditions Assigned
19/20,31/32Previous ISS Missions
The MVIS system is the next generation of vibration isolation systems produced by the CSA to the Microgravity Isolation System (MIM) -2 that flew on STS-85.
Microgravity Vibration Isolation Subsystem (MVIS) uses a magnetic field to suspend a container (roughly the size of a breadbox) for experiments. Sensors and an on-board computer monitor control the position of the container, ensuring it remains free-floating within a certain range that is acceptable for the science experiments inside, thus, vibrations are not transmitted to the container.
The MVIS consists of a distributed set of large actuators, with permanent magnets mounted on the Facility Core Element (FCE) and voice coils attached to the International Standard Payload Rack (ISPR). Three accelerometer assemblies are also mounted on the FCE, housing three accelerometers each. This allows determination of both the linear accelerations and the rotational acceleration of the FCE, and allows for up to three levels of redundancy. There are four Light Emitting Diodes (LEDs) mounted on the FCE with collimated (light beams with parallel rays) beams directed at four two dimensional Position Sensing Devices (PSDs) mounted on the ISPR. This allows for tracking the position and orientation of the FCE with respect to the ISPR.
The Electronics Unit (EU) that controls the MVIS is mounted separately in the ISPR. The EU box is located in the top right section of the FSL. The signals from the accelerometers are digitized within their respective housings and sent to the EU in digital form to minimize susceptibility to electromagnetic noise.
The MVIS has been incorporated integrally within the FSL and is designed to isolate the FCE from the vibrations of the ISS and from disturbances generated within the FSL ISPR itself. The MVIS consists of a distributed set of large gap Lorentz force actuators, with permanent magnets mounted on the FCE and voice coils attached to the ISPR. Three accelerometer assemblies are also mounted on the FCE, each housing three accelerometers. This allows determination of both the linear and rotational accelerations of the FCE. There are four light emitting diodes (LED) mounted on the FCE with collimated beams directed at four two-dimensional position sensing devices (PSD) mounted on the ISPR. This allows for tracking the position and orientation of the FCE with respect to the ISPR. An electronic unit that controls the MVIS is mounted separately within the ISPR. The signals from the accelerometers and PSD are sent to the electronic unit and used by the algorithms that control the FCE. An active control is used to approximately 50Hz, after which the control is passive.