4 research outputs found
Development of compliant mechanisms for real-time machine tool accuracy enhancement using dual-servo principle
Ph.DDOCTOR OF PHILOSOPH
Development of novel micropneumatic grippers for biomanipulation
Microbjects with dimensions from 1 μm to 1 mm have been developed
recently for different aspects and purposes. Consequently, the development of
handling and manipulation tools to fulfil this need is urgently required.
Micromanipulation techniques could be generally categorized according to
their actuation method such as electrostatic, thermal, shape memory alloy,
piezoelectric, magnetic, and fluidic actuation. Each of which has its advantage
and disadvantage. The fluidic actuation has been overlooked in MEMS despite
its satisfactory output in the micro-scale.
This thesis presents different families of pneumatically driven, low cost,
compatible with biological environment, scalable, and controllable
microgrippers. The first family demonstrated a polymeric microgripper that
was laser cut and actuated pneumatically. It was tested to manipulate microparticles
down to 200 microns. To overcome the assembly challenges that
arise in this family, the second family was proposed.
The second family was a micro-cantilever based microgripper, where the
device was assembled layer by layer to form a 3D structure. The microcantilevers
were fabricated using photo-etching technique, and demonstrated
the applicability to manipulate micro-particles down to 200 microns using
automated pick-and-place procedure. In addition, this family was used as a
tactile-detector as well. Due to the angular gripping scheme followed by the
above mentioned families, gripping smaller objects becomes a challenging
task. A third family following a parallel gripping scheme was proposed
allowing the gripping of smaller objects to be visible. It comprises a compliant
structure microgripper actuated pneumatically and fabricated using picosecond
laser technology, and demonstrated the capability of gripping microobject
as small as 100 μm microbeads. An FEA modelling was employed to
validate the experimental and analytical results, and excellent matching was
achieved
DEVELOPMENT OF A NOVEL Z-AXIS PRECISION POSITIONING STAGE WITH MILLIMETER TRAVEL RANGE BASED ON A LINEAR PIEZOELECTRIC MOTOR
Piezoelectric-based positioners are incorporated into stereotaxic devices for microsurgery, scanning tunneling microscopes for the manipulation of atomic and molecular-scale structures, nanomanipulator systems for cell microinjection and machine tools for semiconductor-based manufacturing. Although several precision positioning systems have been developed for planar motion, most are not suitable to provide long travel range with large load capacity in vertical axis because of their weights, size, design and embedded actuators. This thesis develops a novel positioner which is being developed specifically for vertical axis motion based on a piezoworm arrangement in flexure frames. An improved estimation of the stiffness for Normally Clamped (NC) clamp is presented. Analytical calculations and finite element analysis are used to optimize the design of the lifting platform as well as the piezoworm actuator to provide maximum thrust force while maintaining a compact size. To make a stage frame more compact, the actuator is integrated into the stage body. The complementary clamps and the amplified piezoelectric actuators based extenders are designed such that no power is needed to maintain a fixed vertical position, holding the payload against the force of gravity. The design is extended to a piezoworm stage prototype and validated through
several tests. Experiments on the prototype stage show that it is capable of a speed of 5.4 mm/s, a force capacity of 8 N and can travel over 16 mm
Micro/Nano Structures and Systems
Micro/Nano Structures and Systems: Analysis, Design, Manufacturing, and Reliability is a comprehensive guide that explores the various aspects of micro- and nanostructures and systems. From analysis and design to manufacturing and reliability, this reprint provides a thorough understanding of the latest methods and techniques used in the field. With an emphasis on modern computational and analytical methods and their integration with experimental techniques, this reprint is an invaluable resource for researchers and engineers working in the field of micro- and nanosystems, including micromachines, additive manufacturing at the microscale, micro/nano-electromechanical systems, and more. Written by leading experts in the field, this reprint offers a complete understanding of the physical and mechanical behavior of micro- and nanostructures, making it an essential reference for professionals in this field