Microgrippers are commonly used for micromanipulation of micro-objects from 1 to 100 lm and attain features of reliable accuracy, low cost, wide jaw aperture and variable applied force. This paper aim is to review the design of different microgrippers which can manipulate and assemble l-wire to PCB connectors. A review was conducted on microgrippers' technologies, comparing fundamental components of structure and actuators' types, which determined the most suitable design for the required micromanipulation task. Various microgrippers' design was explored to examine the suitability and the execution of requirements needed for successful micromanipulation.

A parallelogram flexible hinge microgripper design made from aluminium alloy 7075-T6 material has been designed and manufactured with purpose of being able to manipulate a 25 μm diameter platinum wire. The structure is unique in that it is actuated using a shape memory alloy. The actuator circuit is designed so that during operation one microgripper arm remains ridged during the gripping process to ensure a consistent reference point whilst the other gripper arm flexes. The focus of the study is on the shape memory alloys capability in terms of providing the correct jaw displacement and displacement time in relation to the circuit input current. The results show a repeatable relationship between displacement and the applied current. In addition, it was shown that the current across the SMA wire increases it dramatically impacts the time taken for the jaws to close. The displacement time is also due to the resistive mechanical force of the microgripper body during operation. Overall the shape memory alloy actuator and optimised gripper design are shown to be useful for a number of industrial applications.

Microgrippers are commonly used for micromanipulation of micro-objects with dimensions from 1 to 100 lm and attain features of reliable accuracy, low cost, wide jaw aperture and variable applied force. This paper studies the design process, simulation, and testing of a microgripper which can manipulate and assemble a platinum resistance temperature probe, made from a 25 lm diameter platinum wire, a 20 mm diameter tinned copper wire, and a printed circuit board type connector. Various microgripper structures and actuator types were researched and reviewed to determine the most suitable design for the required micromanipulation task. Operation tests using SolidWorks and ANSYS software were conducted to test a parallelogram structure with flexible single-notch hinges. The best suited material was found to be Aluminium alloy 7075-T6 as it was capable of producing a large jaw tip displacement of 0.7 mm without exceeding its tensile yield strength limit. A shape memory alloy was chosen as a choice of actuator to close the microgripper jaws. To ensure a repeatably accurate datum point, the final microgripper consisted of a fixed arm and a flexible arm. An optimisation process using ANSYS studied the hinge thickness and radius dimensions of the microgripper which improved its deflection whilst reducing the experienced stress.