Innovative Escapement-Based Mechanism for Micro-Antenna Boom Deployment Marta Tokarz*, Jerzy Grygorczuk*/g15/g3/g54/g87/g68/g81/g76/g86/g225/g68/g90/g3/g45/g68/g85/g93/g92/g81/g78/g68*and Henryk Gut** Abstract This paper presents the prototype of a tubular boom antenna developed for the Polish BRITE-PL satellite  by the Space Research Center of the Polish Academy of Sciences (CBK PAN). What is unique about our work is that we developed an original type of the tubular boom antenna deployment mechanism that can be used widely as a basic solution for compact electrical antennas, booms deploying sensitive instruments, ultra-light planetary manipulators etc. The invented electromagnetic driving unit provides a dual complementary action – it adds extra energy to the driving spring, making the system more reliable,  and at the same time it moderates the deployment speed acting as a kind of damper. That distinguishing feature predetermines the mechanism to be applied wherever the dynamic nature of a spring drive  introducing dangerous vibrations and inducing severe local stress in the structure needs to be mitigated.Moreover, the paper reveals a product unique in Europe – a miniature beryllium bronze tubular boom free  of geometry and strain defects, which is essential for stiffness and fatigue resistance. Both the  deployment mechanism and the technology of tubular boom manufacturing are protected by patent rights. Introduction In December 2009, The Minister of Science and Higher Education signed a decision to grant funding for  the project: 'BRITE: First Polish Scientific Satellite'. Two satellites: BRITE-PL Lem and BRITE-PL  Heweliusz are the Polish contribution to the BRITE mission, developed by a consortium of Canadian, Austrian and Polish institutes. In total, six satellites will perform astronomical observations of the brightest stars, two from each partnering country [1].  The BRITE-PL satellites are almost identical (both measure 20 x 20 x 20 cm and weigh about 7 kg), although BRITE-PL Heweliusz contains some additional experiments designed by CBK PAN. Among them there is an experiment called Micro-Antenna Boom (MAB) – a miniature tubular antenna driven by a  modified escapement mechanism. This paper describes the MAB background, technical features of the  new deployment mechanism used in MAB, conducted test campaign and lessons learned from the  project. It also concisely presents the technology developed for manufacturing a miniature Ø6 mmberyllium bronze tubular boom, not available in Europe before. CBK PAN Heritage CBK PAN has successfully developed devices based on a tubular boom technology since 1993, gaining  therefore an outstanding experience in development of space mechanisms with the use of tubular booms as a lightweight construction material, ideal for antennas and special manipulators where the relation between mass and operational range is crucial. Some of its achievements are shown in Figure 1 and  thoroughly described in [2, 3].  *  The Space Research Center of the Polish Academy of Sciences, Warsaw, Poland ** GUTRONIC Henryk Gut, Warsaw, Poland /g51/g85/g82/g70/g72/g72/g71/g76/g81/g74/g86/g3/g82/g73/g3/g87/g75/g72/g3/g23/g21/g81/g71/g3/g36/g72/g85/g82/g86/g83/g68/g70/g72/g3/g48/g72/g70/g75/g68/g81/g76/g86/g80/g86/g3/g54/g92/g80/g83/g82/g86/g76/g88/g80/g15/g3/g49/g36/g54/g36/g3/g42/g82/g71/g71/g68/g85 /g71/g3/g54/g83/g68/g70/g72/g3/g41/g79/g76/g74/g75/g87/g3/g38/g72/g81/g87/g72/g85/g15/g3/g48/g68/g92/g3/g20/g23/g16/g20/g25/g15/g3/g21/g19/g20/g23 511