Sharif Digital Repository

This thesis is about multidisciplinary design optimization of MRI ¬controlled robots with a nonlinear model approach in the cardiovascular system and simulates its behavior to reach cancer cells. Such robots, designed to perform medical procedures with minimal side effects to the patient, include a set of ferromagnetic nanoparticles attached to the polymer and disposable drugs such as cancer drugs.The disciplines considered in this issue include structure, hydrodynamics, propulsion, controllability, and trajectory. The proposed model in this study, in addition to the main forces acting on the robot such as magnetic force, hydrodynamics, and apparent weight, also examines other forces due to... 

Nanolaunchers are launch vehicles capable of carring light payloads (under 50 kg) to Low Earth orbit and received much attention in the few past years. Launching the nanosatellites grown about 30 times from 2008 to 2017. Since this category of launch vehicles has fewer developing costs and lower thechnology level, they fit developing space technology in our country. Conversely, the demand of high propellant mass fraction and specific impulse may be a serious difficulty to attain this technology.The only operating nanolauncher in the world is SS-520-5 which belongs to Japan and is a three-stage solid propellant launcher. The goal of this project is also the conceptual design and feasiblity... 

In this thesis, the multidisciplinary design of liquid propellant satellite launch vehicle has been done by taking into consideration the effects of fuel sloshing. At first, the theory of multidisciplinary design and one-level architecture with the label of multidisciplinary feasibility have been used. In the following, Gravitational Search Algorithm (GSA) and Particle swarm optimization (PSO) have been developed. Then, the multidisciplinary design cycle began with the design of the liquid propellant system. In the propulsion section, the selection of the optimal fuel, the design of the nozzle, motor and the selection of the optimal engine cycle considering the geometric and mass... 

In this research, a Reusable Flexible Launch Vehicle (RFLV) design problem is presented by Multi-Disciplinary Design Optimization (MDO) approach in primary design phase. Trajectory, structure, aerodynamic, aeroelasticity and thermal protection system are considered as involved disciplines in design problem. The study purpose will be to obtain an optimal trajectory which meets all the control and structure limitation while the estimating body skin and thermal protection thicknesses base on structural evaluating in re-entry trajectory is in process. The flexible launch vehicle body is considered as a free-free Bernoulli-Euler beam and D’alembert’s principle addresses inertia force in static... 

Improving performance and reducing costs is a constant competition between aircraft designers, which has made multi-disciplinary optimization always part of the design process. In the design process of a conventional aircraft, there are various uncertainties in technology levels, mission parameters, costs and operating environment. It is clear that these uncertainties will make the decision-making difficult and lead to uncertainties in the output of the design; on the other hand, considering them will increase the computational cost. Understanding how much the uncertainty of each parameter will affect the overall output of the design and its performance, makes it possible to ignore the...