Structural analysis of microsatellites

Satellite design, development, fabrication, testing and entry into service is a complex process. Each step of this process involves intricate steps to achieve the desired objective. This thesis summarizes a study relating to the area of development and testing of microsatellites to support qualification and eventually preparing a spacecraft for spaceflight. Students in the Space Systems Engineering laboratory (SSE Lab) in the Aerospace Engineering Program are in the process of developing a pair of microsatellites for a technology demonstration in space. After the initial design of the spacecraft is completed in the design phase a significant amount of time is spent on gaining confidence in the design. Various mathematical models are developed to represent the system and to verify its functionality. In the case of the primary structure of microsatellite a finite element model (FEM) is used to predict the behavior of the satellite structure and to verify strength requirements of design before its fabrication. Finite element model its application and results obtained form the majority of this thesis after which concentration is given to the testing phase of the microsatellite. After gaining confidence in the design and fabrication of the components it is important to validate the structure by subjecting it to structural testing. Structural testing is the only means to gain confidence in the design and certifying it for spaceflight. The results obtained from testing show how closely mathematical model (FEM) represents the physical system and provides an important learning experience for the satellite team and to help better understand and improve the design of the next generation of satellites on campus --Abstract, page iii

Novel piezo actuators for surface cleaning

Optical cameras are becoming increasingly common and are used in a variety of applications. With recent progress and transition toward more autonomous systems, the usage of optical systems will be common and widespread. Applications of the optical systems range from autonomous vehicles, home security systems, aviation, extraterrestrial vehicles, spacecraft, and satellites. Imaging systems are used in decision-making in many of these applications. Fouling of the field of view of the imaging system can impede the decision process. An active autonomous cleaning method for the optical surface of the optical systems reliably would be advantageous. The research work focuses on developing a novel piezo actuator that would keep a guard lens on an optical system clean of fouling contaminants using structural harmonic modes. Emphasis is given to camera systems in this work, with the view that the work can be easily expanded to other optical systems based on techniques developed here. The concept developed is to use ultrasonic vibrations and take advantage of the guard lens\u27 structural harmonic modes to remove the contaminants. A process for design, optimization, and prototyping of the systems is presented. The prototype’s efficacy is tested with various fluid and solid contaminants. Analytical models are developed in conjunction with this work to help understanding effects of eccentric load acting on circular plate --Abstract, page iii