abstract: Space systems such as communication satellites, earth observation satellites and telescope require accurate pointing to observe fixed targets over prolonged time. These systems typically use reaction wheels to slew the spacecraft and gimballing systems containing motors to achieve precise pointing. Motor based actuators have limited life as they contain moving parts that require lubrication in space. Alternate methods have utilized piezoelectric actuators. This paper presents Shape memory alloys (SMA) actuators for control of a deployable antenna placed on a satellite. The SMAs are operated as a series of distributed linear actuators. These distributed linear actuators are not prone to single point failures and although each individual actuator is imprecise due to hysteresis and temperature variation, the system as a whole achieves reliable results. The SMAs can be programmed to perform a series of periodic motion and operate as a mechanical guidance system that is not prone to damage from radiation or space weather. Efforts are focused on developing a system that can achieve 1 degree pointing accuracy at first, with an ultimate goal of achieving a few arc seconds accuracy. Bench top model of the actuator system has been developed and working towards testing the system under vacuum. A demonstration flight of the technology is planned aboard a CubeSat. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2016

Thesis is oriented on project construction universal apparatus for introduction and research effects deceleration and impact with possibility setting initial velocity. Basic application proposed test station is crash simulation for diagnostic safety belts. At first there're in work presented physical value that describe action in progress at impact, further safety belts, their testing and test . Considerable volume of work is devoted to project actuation, system obstruction kinetic energy and basic construction. Subsequently is presented proposed construction and performed strenght calculation. In the end there are summarized basic characteristics proposed construction, short financial opinion, process of installation and safety rules for using this equipment.

The thesis deals with a construction of solar tracker designed from the MayTec Profile System using SEW Eurodrive’s electric actuation and accessories. The work describes the design of a laboratory assignment which uses these elements. In the preface information is provided about the construction of solar trackers on which the thesis is based. The next parts of the text are dedicated to each step of the construction design and its variants. A description of how to activate the drive and the design of the connection scheme are also included as well as the technological and construction evaluation. The conclusion contains an economical evaluation of the whole construction.