An Assembly Microfactory for Hybrid Microproducts

The microfactory seems to be one of the most promising approaches for reducing the assembly cost of hybrid microproducts. The microfactory is a miniaturized assembly system with a reduced consumption of space and energy compared to conventional assembly systems. The assembly microfactory includes the same devices of a traditional assembly system: handling, joining, monitoring devices and also proper strategies to assure a correct assembly. The assembly microfactory here presented consists of various prototypes and commercial handling devices integrated in the same assembly environment. The complete system is able to automatically perform different assembly tasks. As a bench test for evaluating the microfactory performance, a product made of several microcomponents of different materials and shapes has been designed. The operations necessary for its correct assembly are: pick and place of parts with various shapes, peg-in-hole of microcylinders with small clearance, alignment and positioning of microparts. The main goal of the developed microfactory is to demonstrate the reliability and the feasibility of the tested devices in complex microhandling tasks and their capability to be simply integrated in a microassembly environment. Another purpose is to show the feasibility and the flexibility of the adopted assembly strategy in the micro domain. Several different transporting and grasping devices find application in the assembly system. Two innovative electrostatic feeders and an electrostatic sorter are used to sort, transport and position microspheres, microcylinders and microgears with dimension of few hundreds microns. Four different types of grippers (a mechanical, an electrostatic, an adhesive and a pneumatic one) supported by a 3 DOFs commercial micropositioner have been used to execute peg-in-hole of microcylinders with a diameter of 500 μm and pick and place of microspheres with a diameter in the range of 800–1100 μm.