MEchanics GAthering –MEGA– Seminar: Falling cat flexure-based bearingless reaction wheel


Event details

Date 01.12.2022
Hour 16:1517:15
Speaker Patrick Flückiger (INSTANT-LAB, EPFL)
Location Online
Category Conferences - Seminars
Event Language English
Today’s main device for controlling the orientation of satellites is the reaction wheel.  This consists in a motorized flywheel which is accelerated/decelerated in order to export torque to the spacecraft by Newton’s third law of action/reaction. Ball bearings are the current solution for the flywheel, however, these have a number of issues such as wear, a limited lifetime, friction and stiction. This talk will present an alternative mechanism which has the same properties as a conventional reaction wheel, but which contains no rotating bearings and is implemented entirely with flexures. The benefits of this solution are the absence of wear, friction and stiction as well as vacuum-compatibility and extended lifetime. It so happens that this mechanism follows the dynamics of a falling cat which manages to re-orient itself during a fall in order to land on its feet.

Patrick obtained a Bachelor's and Master's degree from EPFL in Microengineering, with a specialisation in Optics and a background in Life Sciences. He then worked at Instant-lab, EPFL, for two years on diverse flexure-based mechanisms. He started a PhD back at Instant-lab in August 2022 under the supervision of Prof. S. Henein. His research focuses on creating the flexure equivalent of a reaction wheel for spacecraft attitude control.

Practical information

  • General public
  • Free


  • MEGA Seminar organizing committee



reaction wheel altitude control flexure compliant mechanism aerospace falling cat

Event broadcasted in