Enhanced Vibration Isolation Using a Magnetic Linear Gear for Highly Demanding  Aerospace Applications   José Lui s Perez -Diaz**, Ignacio Valiente- Blanco*, Juan Sanchez García- Casarrubios*, Cristian Cristache*, Fernando Rodriguez -Celis*, Judit Esnoz -Larraya*, Efrén Diez -Jimenez**   and José Luis Perez -Alamo* Abst ract  Z-Damper  is a new technology for vibration isolation in aerospace structures and equipment that  takes advantage of  impedance matching inside a magnetic linear gear to optimize vibration isolation  performance and, at the same time, reduce weight and space r equirements.  Since there  is no  contact  between moving parts  except from the supporting linear bearings , it is suitable for long- life operation in space environmental conditions  without wear or debris generation. A t heoretical model describing the dynamic behavior of the Z -Damper is presented in this paper.  Additionally, two demonstrators have been designed, manufactured and tested for the FP7 Clean Sky Z - Damper project. One breadboard model is an empowered eddy current damper (Z -Damper)  for operation  at high temperatures and the other prototype is a reduced mass tuned vibration absorber (Z -TVA). The Z - Damper demonstrated a viscous damping coefficient up to 35 Ns/mm at 200ºC. The Z-TVA was designed  with a resonant frequency of 18 Hz. With a mass of only 9.6 kg, it demonstrated similar performance to a  classic tuned vibration absorber of 150 kg.   Intr oduction and State of th e Art  High  performance  vibration isolation solutions with small mass and envelope are needed for applications  such as micro -vibration isolation [1], damping of launch loads [2], suppression of  spacecraft -borne  disturbances [3] , or dampers for deploy mechanisms and structures [4].  Magneti c mechanisms  such as bearings  [5], gears  [6] or dampers  [7] are drawing increasing attention due  to their convenient properties for their use in space environment: l ubrication i s no longer required, wear and  debris  generation  are eliminated and  they are able to operate in a wide temperature range. Finally   they  present  no backlash, which makes them good candidates for precision positioning without contact  [8] [9] .  Magnetic dampers based on hysteresis or eddy current energy dissipation are frequently used in space  systems because of their high temperature range, their absence of  damping fluids , their vacuum  compatibility , and their long space heritage. However, the performance of any eddy current damper is  limited by the fact that the damping constant is proportional to the vibration speed. Therefore, for low  frequency vibrations or short strokes, the capacity of the damper s is highly limited.   Another  frequent solution for vibration isolation of structures excited at a known frequency are tuned  vibration absorbers (TVA)  [10]. TVA working principle is based on storing  the vibration energy into a  properly tuned resonant mass attached to the main vibrating body. Their  effectiveness is directly related to  the total mass of the absorber . There fore, the required envelope and the costs induced by maintenance  and installation are also main factors to be considered in many application cases.   In thi s paper , a new technology  is presented for vibration isolation that takes advantage of  the impedance  matching inside  a linear magnetic gear to enhance the performance of any damping system proportionally  *MAG SOAR S.L, Valdemoro, Spain ** Universidad de Alcalá, Alcalá de Henares, Spain Proc eedings of the 44th Aerospace  Mechanisms Symposium, NASA Glenn Research Center, May 16-18, 2018   NASA/CP—2018-219887 177