טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentShvets Zeev
SubjectFunction-Based Assembly: An Investigation of Assembly of
MEMS-Based Rate Gyroscopes
DepartmentDepartment of Mechanical Engineering
Supervisor Professor Eyal Zussman


Abstract

MEMS-based devices make use of hybrid micro-optical, micro-mechanical, and sensing elements.  The propagation of this technology will depend on manufacturing techniques being found which allow these systems to be manufactured at low cost

The assembly of MEMS-based devices in certain applications requires alignment within tolerances better than ±1μm. This standard has proven to be difficult to achieve consistently due to manufacturing and assembly errors.  This thesis describes an active alignment process which incorporates the actual geometric parameters of the microelements as well as geometric constraints in order to determine the optimal location of the microelements in the assembly.  The determination of this location guarantees optimal functionality of the device and helps achieve tight alignment tolerances without compromising the device design. In conventional assembly techniques, objects are integrated using an active alignment procedure.  This usually is performed by matching a set of features (e.g., alignment marks) on the object and on the standard frame by means of an affine motion in order to minimize any error in placement. The advance of such approach to the assembly and alignment is the independence of any alignment marks on components. Also the careful analysis of functional requirements can improve the operation of the device and reduce the unfit parts ratio. Such algorithm can be involved in any robotic assembling system with computer vision based feedback . The effectiveness of this approach is demonstrated in a micromachined vibrating rate gyroscope assembly.  Simulation and measurements taken of the assembled rate gyroscope confirmed an assembly accuracy of better than 1μm.